The Honble. Robert boil. THE WORKS OF THE HONOURABLE Robert Boil, Esq EPITOMISED. VOL. I. By RICHARD BOULTON, of Brazen-Nose College in Oxford. Illustrated with COPPER PLATES. — Consilium est, universum Opus Instaurationis (Philosophiae) potiùs promovere in multis, quam perficere in paucis. Verulamius. LONDON, Printed for J. Phillip's at the King's Arms, and J. Taylor at the Ship in St. Paul's Churchyard, MDCXCIX IMPRIMATUR Liber Cui Titulus, THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED By RICHARD BOULTON, JOHN HOSKYNS, V P. R. S. Vecesimo Septimo Martii, 1699. ERRATA. IN the Preface, pag. 2. lin. 13. read less entertaining Digressions. P. 64. for dissolve into Crystals, read dissolve, shoot into Crystals. P. 433. l. 7. read which would not have been done, were, etc. P. 436. l. 1. read in our Third Plate. In the Table, under the Letter T. l. 2. deal their. TO THE Right Honourable JOHN Lord SUMMER, BARON of Evesham Lord High Chancellor of England, AND Precedent of the ROYAL SOCIETY; And to The Honourable Sir JOHN HOSKYNS, Vice-President: Together with the Council and Fellows Of the said SOCIETY, INSTITUTED For the Advancement of Natural Knowledge; This VOLUME, Entitled an EPITOME OF Mr. boil's WORKS, Is humbly Dedicated by RICHARD BOULTON. TO THE Right Reverend Father in GOD NICOLAS, Lord BISHOP of CHESTER. My LORD, THAT I presume to lay a Book before Your Lordship, which bears so mean a Name as mine in the Title-Page, might want a better Apology than I could make, were there not likewise the Illustrious Name of that justly esteemed and most Famous Author, the Honourable Mr. Boil before it. For were the following Sheets, entirely the Products of my weak Endeavours only; I should think it no small Piece of Vanity to hope for Your Lordship's Notice, and much more to expect your Patronage: But, since the Honourable Author's Works have sufficiently recommended themselves to the Learned World; and more especially to those that are most Eminent for Learning themselves; He cannot but already, amongst Those, have deserved Your good Esteem; and therefore, should I endeavour an Encomium of so Great a Man, by way of Apology for my present Presumption, I should but let Your Lordship see, that all I can say of so Eminent a Person, would come far short of the Esteem You have for him already: Not that I can pretend to know Your Lordship's Sentiments in any Particular, any further, than I may presume to guests, by the Notion I have of Your Lordship's Esteem for Learning and Learned Men. But tho' the Name of Mr. boil may be sufficient to recommend the Honourable Author's Works to Your Lordship, and the rest of the Learned World; yet if Your Lordship will be pleased to condescend to Patronise Your most Humble and Obedient Servant, who hath the good Fortune to Conduct them into the World, and to extract those purer Streams of Knowledge, which are separated from the less discerning Part of Mankind, by polite Apologies and Florid Complimental Digressions, It will be the greater Happiness, that I have the Honour to be Just to the Author and Serviceable to the World; But much more, that I have at the same time, so Favourable an Opportunity of expressing my Gratitude for the Favours which Your Lordship hath already been pleased to bestow on me: Favours, which are much more valuable, because Your Lordship's; and which carry with them a double Obligation of Gratitude; the One to Your Lordship and the Other to my good Friend and Worthy Patron Dr. Robert Angel, to whom I am infinitely Obliged for Your Lordship's Favour, and for being first made known to Your Lordship. But it will not be the only Happiness to me, that Your Lordship is pleased to Patronise my present Undertaking; but it may in a great Measure Contribute to their Candid Acceptance by the World, who will put a higher Value upon them, for Your Lordship's Favourable Approbation. Indeed, were it Generally received and agreed on, what some People hold, viz. That Philosophy is prejudicial to Religion; I should have more Reason to beg Your Lordship's Pardon, than Your Patronage; since it must be in Vain to hope, that One, who promotes the Latter, by Instructive Doctrine; and what is more, an Exemplary Life, to be imitated, but not paralleled; should encourage any thing, that may be of Disservice to that: But I need not tell Your Lordship, that the Honourable Author hath made it appear, That we may search into Efficient Causes, without denying the. Alwise Author of Created Being's, his just Attributes: For, whoever diligently searches into Efficient Causes, cannot but discern the Necessity of an Omnipotent Creator, who first established the Laws of Nature, and gave them their due Limits; and our Author having made it evident, that Efficients themselves, direct us to Final Causes; and confequently rather dispose and incline a Man, than hinder him from being a Good Christian; your Lordship needs no other Inducements to promote it. And indeed, were I not satisfied, that Philosophy, if rightly made use of, by the Effects it hath upon myself, did not enable Me the more to discern the Shortness of the Utmost Attainments of Finite Capacities, and to adore what I cannot comprehend; I should be so far from desiring Your Lordship's Patronage, that I should be ready to oppose it myself, to the utmost of my Weak Endeavours: And were it not too soon to make Your Lordship Promises, before I have qualified myself to write any thing of my own, worth Your Lordship's Notice, I should not be backwards to say, That I may in a few Years, show that it will afford us no small Light in explaining the Mosaic Creation, in directing us to frame some faint Ideas of the Methods by which the Omnipotent Fiat brought the World to what it now is, and to prove the Works of the Omnipotent Creator, as Historically delivered by Moses, consonant with Philosophy. But I am afraid, that, endeavouring to make an Apology for this Dedication, I ought to make another, for having been too tedious already; since Your Lordship's own Judgement, will satisfy You of the Usefulness of Philosophy, and since that Consideration is enough to induce You to encourage it. Yet I cannot persuade Myself, so soon to pass by this Opportunity of expressing my Gratitude to Your Lordship: nor can I forbear reflecting on my own Happiness, under Your Lordship's Patronage: For as no one better understands, how to encourage the Endeavours of those, that make Improvements in Knowledge their Aim, than those that are most intimately acquainted with it, and than Your Lordship; So it is an equal Happiness to be under the Protection and Favourable Eye, of a Patron so desirable: Neither is it any Vain Opinion I have of my own Merit, that makes me think myself Happy under such a Patron, but rather the Sense of my own Weakness; for could I persuade myself that I deserved Your Lordship's Favour, or the Favour of some Others, both eminent and Learned, to whom I am obliged: I must be very vain indeed. But notwithstanding the Sense I have of my own Weakness, Your Lordship's Favour will encourage me to improve the small Talon I have, since in the Search of Truth, Est aliquid prodire tenus, si non datur ultra. But My LORD, the World, who are wont to find in Dedications, the Characters of their Patrons, may wonder that I have declined the Usual Method, since any one that knows Your Lordship cannot want Materials for a Character, that might be of Use to the World, in setting them a Good Pattern to imitate: Yet since Your Lordship's Character would be drawn amiss by so mean a Pen as Mine; I would rather be thought out of the Common Road, than mistaken in it; since any Body that knows what Character belongs to a Truly Apostolical Bishop, is not unacquainted with Your Lordship's: Therefore since no Encomiums can add to that which can only be augmented by a Continuance of Your Life; the Fear of Misrepresenting, is the Reason I decline it. But not to take up too many of Your Lordship's precious Minutes, which are always Employed in doing Good, and promoting Christianity in its Original Stream; that Your Lordship may live long, for the Honour of the Church, and the Good of those that are under Your Care, is not only the Wishes of ●hose that think themselves happy under the inspection of Your Lordship; but more particularly of, My LORD, Your LORDSHIP's Most Dutiful, and Most Obedient Servant, RICHARD BOULTON. Plate the Second Fig: 1 pag. 407 Fig: 2 pag: 〈◊〉 Fig: 6 pag: 432 Fig: 3 pag: 416 Fig: 4 pag. 410. Fig: 5. pag: 420 Plate the Third. pag: 435. Plate the fourth. pag: 435 Plate 5. Fig: 1. pag. 438 Fig: 3. pag. 454 Fig: 2 pag. 452. Fig: 4. p. 459 Plate. 6. Fig: 1 pag. 443 Fig: 3 pag. 445 Fig: 2. pag. 443. Fig: 4. pag. 447 Plate. 7. Fig: 4. p: 470 Fig: 2 pag 4●● Fig: 3 pag. 470 Fig: 1. pag. 456. Plate. 8. Fig: 3 pag. 474 Fig: 4 pag. 〈◊〉 Fig: 5. pag. 475 Fig: 7. p: 477 Fig: 8. p: 477. Fig: 6 pag. 476 Fig 〈◊〉 pag. 4●● Fig: 2 p ●●4 THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. BOOK I. CHAP. I. Considerations and Experiments concerning the Origin of Forms and Qualities. The Division of this Chapter. THAT before I descend to a more particular Consideration of the Doctrine of Forms and Qualities, I may premise some General Apprehensions of the Doctrine, to be collated with, and to be either confirmed, or disproven by what follows of Particular Forms and Qualities; I will, at the Entrance, give you a short Account of our Hypothesis, comprised in the Eight following Particulars. We teach then (but without peremptorily asserting it) Matter Defined. I. That the Matter of all Natural Bodies is the same, Namely, a Substance Extended, Divisible and Impenetrable. Motion the Catholic Agent of the Universe. II. That since there could be no change in Matter, if all its Parts were perpetually at rest amongst themselves, to discriminate the Catholic Matter of the Universe, into a Variety of Natural Bodies, it must have Motion in some or all its Parts, which Motion must be variously determined. And though it is manifest to Sense, That there is Local Motion in Matter, yet Motion is not congenite to Matter, nor coeval with it, Local Motion being not included in the Nature of Matter, which is as much Matter when at rest as in Motion: And though it be hotly disputed, How Matter came by that Motion, by those who acknowledge not an Author of the Universe; yet, since a Man is not the worse Naturalist, for not being an Atheist, we allow that the Origin of Motion in Matter is from GOD; and that, since it is unfit to be believed, that Matter in Motion left to itself, should casually constitute this Beautiful and Orderly World, Guided by GOD in the Creation of Things. it is not amiss to think, That the Wise Author of Things, guided the first Motions of the small Parts of Matters so, that they might convene after a Manner requisite to compose the World, and especially did contrive those Curious and Elaborate Engines, the Bodies of Living Animals, enduing most of them with a Power of propagating their Species. But to pass by such Notions, I shall proceed to what remains requisite to explicate the Origin of Forms and Qualities, as soon as I have taken Notice, That Local Motion seems to be indeed the Principal amongst Second Causes, and the Grand Agent of all that happens in Nature; Bulk, Figure, Rest, Situation and Texture, being the Effects of Motion, or the Conditions and Requisites, which Modify the Operation, as in a Watch, or Key, it is Motion that makes all the other Requisites useful. Motion, Size and Shape, three Primary Affections of Matter. III. That Matter being Naturally by a variously determined Motion, divided into Parts, each of those Parts must needs have a peculiar Size and Shape: So that there are three Essential Properties, or Primary Affections of the Parts of Matter, Magnitude, Shape, and either Rest or Motion; the two first of which may be called Inseparable Accidents: Inseparable, because Bodies extended and finite, cannot be devoid of a Determinate Shape; Accidents: because that whether Physical Agents may have a Power to alter the Shapes, or subdivide Bodies or not, yet mentally they may do both without destroying the Essence of that Matter. Whether there be in Bodies Qualities and Accidents, distinct Entities from them. Whether these Accidents may be called the Modes, or Primary Affections of Bodies, to distinguish them from those more compound Qualities (as Colours, Tastes, and Odours) or the Conjuncts of the smallest Parts of Matter, I shall not now determine; only one thing which is taught by the Modern Schools concerning Accidents; Namely, That there are in Natural Bodies Real Qualities, and other Real Accidents, which are no Modes of Matter, but Entities distinct from it, and which may exist separate from all Matter. To clear this Point, we must take Notice, That Accident is used in two several Senses; for sometimes it is opposed to the fourth Predicable (Property) and is defined, That which may be Present or Absent, without the Destruction of the Subject; as a Man may be sick or well, yet a Man: And this is called Accidens Praedicabile, to distinguish it from what they call Accidens Praedicamentale, which is opposed to Substance; and as Substance is commonly defined to be a thing that subsists of itself, and is the Subject of Accidents; so Accident is said to be Id cujus esse est inesse: And therefore Aristotle, who usually calls Substances 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, Entities, calls Accidents 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, Entities of Entities, these needing a Subject of Inhaesion. And we are likewise to take Notice, That, according to them, That is said to be in a Subject, which hath these three Conditions; That however it (1) be in another thing, (2) is not in it as a part, and (3) cannot exist separately. This premised, it will appear easily, that if they will not allow these Accidents to be Modes of Matter, but Entities really distinct from it; they make them indeed Accidents in Name, but represent them under such a Notion, as belongs only to Substances, the Nature of a Substance consisting in this, that it can subsist of itself. So that we may consider, when a Bowl runs along or lies still, that Motion or Rest, or Globous Figure, are not any parts of the Bowl, nor real and Physical Entities distinct from it, but certain Modifications, and several Capacities in relation to the Matter of that Bowl. An Excursion about the Relative Nature of Physical Qualities. Qualities the result of a peculiar Modification. BUT because this Notion about the Nature of Qualities may be of some importance, I shall illustrate it a little further. We may consider then, That whoever was the first Inventor of Locks and Keys, they both consisted of a piece of Iron, of a determinate Figure; but in respect of the Congruity betwixt the Wards of the Locks, and those of the Keys, they each of them obtained new Capacities; it being a peculiar Faculty of the Key to unlock, as of the Lock to be unlocked by it; yet by these new Attributes, no real or Physical Entities were added, either to the Lock or Key: so those Qualities, which we call Sensible, tho' by virtue of a Congruity or Incongruity in point of Figure or Texture to our Sensories, the portions of Matter they modify, are enabled to produce various Effects, upon whose account we make Bodies to be endued with Qualities, yet they are not in those Bodies any real distinct Entities, or different from the Matter itself, furnished with such a determinate Bigness, Shape, or other Mechanical Modifications. It is reckoned amongst the principal Properties of Gold, that it is dissoluble in Aqua Regis; and if one should invent another Menstruum, that will in part dissolve pure Gold, yet the Nature of Gold is not at all different now, from what it was before either of those Menstruums were invented, there no new real Entities accrueing to it, without the Intervention of a Physical Change in the Body itself, by the Addition of these Attributes. Proved by Physical Observations. There are some Bodies neither Cathartick, nor Sudorific, with some of which Gold, being embodied, acquires a Purging Virtue, and with others Diaphoretic Qualities; and Nature herself doth, either Artificially, or by Chance, produce so many things, that have new Relations unto others: And, Art especially assisted by Chemistry, may, by variously dissipating Natural Bodies, or compounding either them or their constituent Parts with one another, form a multitude of new Productions, which will be able each of them to cause new Effects, either immediately upon our Sensories, or upon other Bodies, whose changes we are not able to perceive; so that no Man can know, but that the most Familiar Bodies, may have a multitude of Qualities, that he dreams not of; and a considering Man will hardly imagine, That so numerous a crowd of real Physical Entities can accrue to a Body, whilst in the Judgement of all our Senses it remains unchanged. Again, Glass beaten is commonly reckoned amongst Poisons, which deleterious Faculty is no superadded Entity distinct from the Glass, but depends on the sharp Points and cutting Edges of the Fragments, which by Mechanical Affections, cut and wound the Membranes of the Stomach and Guts; from whence follow great Gripe and Contortions, and often a Bloody Flux by the Perforations of the Capillary Vessels, and horrid Convulsions by the consent of the Brain and Cerebellum, as also great Dropsies, occasioned by the loss of Blood: And that those Effects depend on the Edges and Points of the Fragments, appears, because when the Guts are sufficiently lined with Slime, or the Corpuscles of the Glass are ground fine, they pass without damage along with the Execrements. And this may put us in mind, That the Multiplicity of Qualities, in the same Natural Bodies, may proceed from the bare Texture, and other Mechanical Affections of its Matter: For every Body is to be considered not barely as an entire distinct Portion of Matter; but as it is a Part of the Universe, placed amongst a great number and variety of other Bodies, upon which it may Act, and by which it may be Acted on, in many ways, which are falsely thought to be distinct Powers or Qualities in the Bodies, by which those Actions and Passions are produced. And every Portion of Matter thus considered a few Mechanical Affections are sufficient to diversify it from other Bodies: As in a Watch, there are a great many Qualities; as to show the Hours, to strike, to give an Alarm, or to show the Age of the Moon and Tides; yet these are all to be attributed to the determinate Shape and Texture of the Parts of it, and the Motion of the Spring. So the Sun hath a Power to harden Clay, and soften Wax, to melt Butter, and thaw Ice, and a great many more, which seem contrary Effects; yet these are not distinct Faculties in the Sun, but the Productions of Heat diversified, by the different Textures of Bodies it chances to work upon. And thus much (Pyrophilus) may serve to remove the Mistake, That every thing Men are wont to call a Quality, must needs be a Real and Physical Entity. To conclude this Excursion, I shall add this short Advertisement, That to make what I have declared more intelligible, I have rather done it by Examples, than Definitions; the latter being more difficult, because of the difficulty of assigning the true Genus' of Qualities. And, Here it may not be amiss to take Notice, That Aristotle himself does not only define Accidents, without setting down their Genus; but when he comes to define Qualities, tells us, That Quality is that by which a Thing is said to be Qualis; which is to define the Thing by the Same, without denoting its Genus; for 'tis supposed to be as little known what Qualis is, as what Qualitas. Besides, 'tis a Doubt whether it be not as false as obscure; for to the Question Qualis res est, Answer may be made out of some, if not all of the other Predicaments of Accidents. Posture, Order and Texture Secondary Affections of Matter. iv Besides the forementioned Primary Affections of Matter, viz. Motion, (or Rest) Bulk and Shape; which a portion of Matter singly by itself must have; if all the rest of the Universe were annihilated, there being now in the Universe multitudes of Corpuscles mixed together, there arise two new Accidents, or Events: The one relates to its Posture, in reference to the Bodies about it (whether erected, inclined or horizontal) and the manner of those Bodies in reference to each other, which may be called Order; as Aristotle in his Metaphysics recites this Example, from the Ancient Corpuscularians. A and N differ in Figure, and A N, and N A in Order; Z and N in Situation; and Posture and Order indeed seem both reducible to Situation. And, lastly, when these Corpuscles do so convene, as to make up a Body; the Disposition and Contrivance of Parts in the whole, may be called the Texture of it. Colours, etc. no inherent Qualities, V We are to consider, That the Bodies of Sensible and Rational Being's, being endued with several Senses, adapted so, as to receive from without various Impressions, according to the Diversity and peculiar Texture of each Part; these Impressions being falsely imagined to proceed from real Qualities, inherent in those several Objects, have been signified by several Names, as Heat, Colour, Sound, Odour, together with a vast variety of each, as so many Species, to be ranked under these Genus'; which really depend on the Figure, Shape, Motion, Texture, and the Manner in which these Bodies, differently modified, variously affect the Senses. VI But here is one Difficulty to be removed, which is, That besides the Sensible Qualities, evident in Relation to our Senses, they have an absolute Being irrelative to us; since they do not only Operate upon our Senses, but other inanimate Bodies. To clear which, I have several things to represent. But Secondary Effects of Matter. 1. That there are Simple, and more Primitive Affections of Matter, from whence these Secondary Qualities do proceed, and on which they depend. 2. The Knowledge we have of the Operations of Bodies, proceeds from some Sensible Quality, or some more Catholic Affection of Matter; as Motion, Rest, or Texture; generated, or destroyed in one of them. 3. We are to consider every distinct Body that affects our Senses, not as a bare Lump of Matter, of that Bigness and outward Shape that it appears of, most of them having their Parts curiously contrived, and in Motion too. And likewise we are to consider the Universe that surrounds us, as a great Engine, with no Vacuity, or no considerable one betwixt its Parts; and the Actions of Particular Bodies, are not to be estimated, as if two Portions of Matter of their Bulk and Figure, were placed in some Imaginary Space beyond the World, but as situated in the World, as now constituted, and their Actions liable to be promoted, or hindered, or modified by the Actions of other Bodies about them; for it is not giving of a Concave Speculum, that Figure, that enables it to burn Wood, or melt Metals; but the Sunbeams thrown together into a Point, by the help of that Concavity. And to show how various and different Effects the same Action of a Natural Agent may produce, according to the several Dispositions of the Bodies it works upon, we may consider, That tho' in two Eggs, the one Prolific, the other Barren, before Incubation, the Sense can distinguish no Difference; yet their internal Disposition is so different, that if they be both exposed to an equal Degree of Heat, the one will be changed into a putrid Fetid Substance, and the other into a Chick, furnished with a variety of Organical Parts of very curious Textures. 4. I grant that Bodies may have those Qualities we call Sensible, tho' there were no Animals in the World, every Body having such a Disposition of its Constituent Corpuscles, which duly applied to the Sensory of an Animal, would produce a Sensible Quality, which another would not. So that if there were no Sensitive Being's, those Bodies that are now the Objects of our Senses, would be but Dispositively endued with Colours, and the like, and Actually only with those more Catholic Affections of Bodies, Figure, Motion, Texture, etc. To illustrate which, we may consider, That, tho' an Echo is supposed to be a Peculiar Faculty, in the Rock, yet it is nothing but a Repercussion, and the undulated Motion of the Air, reverberated by that Rock, which striking upon the Ear, causes such a Sensible Quality. Qualities act by virtue of Local Motion. 5. The Sensible Qualities, which are acquired by the Action of one Body on another, are not otherwise produced, but by some Local Motion of Parts, or some change of Texture produced by that Motion: For, when a Pin, by a Dissolution of the Continuity, causes Pain, that Pain is only a Consequent of its Motion, which superadds no real Quality to the Pin, which it had not before: And therefore I shall intimate, That when for shortness of Speech, I make use of the Word Qualities, I would be understood to mean them in a Sense suitable to the Doctrine abovementioned. As when I would say, Roughness is apt to offend and grate the Skin, I would mean, That a File or other Body, by having upon its Surface a multitude of hard, and extant Parts of an Angular or Sharp Figure, is qualified to cause the mentioned Effect. Of the Nature of a Form. Form the Result of a Congeries of united Accidents. VII. We may now consider further, that certain conspicuous Accidents being associated into Bodies; those Bodies are distinguished by Genus' and Species, as they are referred to a more Comprehensive sort of Bodies, or to a narrower species, or Individuals: As amongst Fossils', the Superior Genus comprehends both Metals, Stones, etc. each of which Concretes, in respect of that Genus, are Species, comprehended, as they are Fossils', under that Superior Genus. Now when those Accidents, which are Essentially requisite to compose a Body, of this or that Kind, are united; the Texture of that Body is called the Form: which, tho' some think to be a kind of Soul, which, when united to a Natural Body, acts in it, by virtue of several Qualities inherent in that Soul, yet, really, it is nothing distinct from that Matter, but only such an Agreeable Convention of Accidents, as by common Consent, are reputed sufficient to make a Portion of Universal Matter belong to this or that Determinate Genus, or Species of Natural Bodies. And those Qualities in Bodies, which are usually ascribed to the Substantial Form, do not proceed from any Real Substance distinct from Matter, but a Convention of those Primary Mechanical Affections of Matter beforementioned; viz. Bulk, Shape, Motion or Rest; and the Texture thence Resulting, which is the Form, or Essential Modification; which Convention of Accidents are capable of performing what we usually ascribe to a Form, since they are sufficient to discriminate it from all other Species of Bodies. The Effects of Forms whence. And since the Form of a Body by some is asserted to be the Principle of its Operations, it may not be amiss here to take Notice, That besides those Operations, that proceed from the Essential Modification of the Matter, the Body being considered per modum unius, as one entire Agent, it may have several other Operations in Respect of the Particular Corpuscles of which it is composed; as in a Watch, besides those things it does as a Watch; the several Constituent Parts of it, as the Springs, Wheels, etc. may, each have their peculiar Attributes, as Bulk, Shape, etc. upon the Account of which it may do several things besides what it performs as a Watch: And if the Effects of those Corpuscles of which Bodies are composed are sometimes so Prodigious; as for Instance, the Effects which Fire produces by its Heat, we need not wonder that such great things may be done, as we sometimes see by several Active Qualities convening into one Body; since we see Engines perform very strange things, by virtue of those Accidents, viz. the Shape, Size, Motion, and Contrivance of their Parts. Of Generation, Corruption, and Alteration. VIII. Having thus according to our Hypothesis shown what is meant by a Form, it remains that we explain, what is to be understood by Generation, Corruption, and Alteration. In order to which we are to consider, Considerations requisite to the Doctrine of Generation, etc. 1. That there are some Particles of Matter so small, that tho' they be Mentally, or by Divine Omnipotence, divisible, yet are scarce Actually divided by Nature; which in that respect may be called Minima Naturalia. 2. That there are Multitudes of Corpuscles, consisting of a Coalition of several of these Minima Naturalia, whose Bulk is so small, and Adhesion so close, that tho' not absolutely indivisible into the Minima Naturalia, yet very seldom are actually divided; and these are the Seeds or immediate Principles of many sorts of Natural Bodies, as Earth, Water, etc. 3. That both the Minima Naturalia, and those Primary Clusters resulting from the Coalition of them, having their determinate Bulk and Shape; when these are united, the Size and Shape by their Juxta-position must be often altered, and oftentimes their Tendency in and to Motion varied; which Accidents will also happen when they are disjoined, by which Unions and Separation of Parts, the Size and Shape being variously altered, they are accordingly adapted to several Pores, upon which Account they have different Effects upon several Bodies. 4. That when several of these Corpuscles are associated, and put into Motion, that Motion will produce great Alterations, and many new Qualities in the Bodies they compose; as Air swiftly moved, is called Wind, and feels colder to the Touch; and Iron rubbed against Wood, feels warm. But besides these Invisible Alterations, there are several which are visible; as when the Particles, by knocking together, are broke and disjoined, and by that means acquire new Forms, their Bulk and Figure being altered, and the Texture and Interstices of the Parts being also varied: Thus Water froze, acquires Firmness, and loses its Transparency; and Milk, by a languid intestine Motion of its Parts, in hot Wether, turns into a thinner Liquor, and into Cream, which agitated in a Churn, turns to an Oily Substance, and a thin fluid. So Fruit, by being bruised, loses its Colour, Taste, Smell, and Consistence: From whence it appears, that Motion is not only the Grand Agent in Altering, but Composing and Constituting the Forms of Bodies. 5. And that since the Qualities of Bodies are derived from the Size, Shape and Motion, and the Texture, or Essential Modification of the Parts of Matter, we need not deride the Ancient Atomists, for attempting to deduce Generation and Corruption from the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, the Convention and Dissolution, and their Alterations from the Transpositions of their Atoms; tho' I believe they all three are concerned in Generation, as well as Corruption and Alteration. Generatition, Corruption, etc. what. These things premised, our Doctrine of Generation, Corruption and Alteration may be comprised in a few Words; for when there is such a Concurrence of Accidents as are requisite to constitute any determinate Species; such a Species is said to be generated; in which Action no new Substance is produced, but that which was Preaexistent obtains a new Manner of Existence, or new Modification; which is evident in the making of a Watch, where the Parts are the same, when separate, as when joined, only the Union in respect of the whole, makes a new Body of a peculiar Modification: And when that Union of Accidents, which denominates a Body generated, is destroyed and dissolved, that Body, losing its Essential Modification, is said to be corrupted; for as a Watch is said to be made, when its Parts are put together; so when they are again displaced, it is no longer called a Watch. Hence we may learn to understand that Axiom, Corruptio unius est Generatio alterius; & è contrà for when those Accidents which make one Body, are by any means altered, it loses that Denomination, and being modified anew puts on another Form, and becomes a Body of another Kind. Putrefaction what. And here before we wholly leave off the Consideration of Corruption, it may not be amiss to take Notice, That Putrefaction is but a peculiar kind of Corruption, where the Texture of Matter is more slowly altered, than in Corruption in a strict Sense; and also, that all the Essential Qualities are not destroyed. Alteration what. And here it may be seasonable to take Notice also, That tho' the Form of a Body depends on its Essential Modification, yet it seldom happens, that a Body acquires no other Qualities, than what are essentially and absolutely necessary to denominate its Species; since in most Bodies it falls out, that there are some Qualities, which whether absent or not, done't essentially change the Subject; the Acquisition or loss of which is called Alteration (or by some Mutation). Generation and Corruption, depending on an Acquisition or Loss of the Essential Qualities of a Body. But to conclude this Theoretical Part, let us reflect briefly on the Fruitfulness of this Mechanical Hypothesis: For, according to this Doctrine, the World we live in is not a moveless indigested Mass of Matter, but an 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, or Self-moving Engine, whose Parts are most of them in a variety of Motions; and so close set together, as to leave no Vacuities, or very little ones betwixt them. And since the various Coalitions of these Parts, are enough to make several Bodies of as various Textures; and we see such a vast variety of Words made only of 24. Letters differently situated, we need not wonder that so many, and such multitudes of Bodies should result from Matter differently Modified, by a Coalition of Matter subject to so many Accidents, as Matter in Motion must be, its Parts being subject to be altered variously by the Addition, Comminution, or Substraction of a few Parts of Matter. CHAP. II. Further Considerations concerning Particular Qualities. HAVING said thus much of the Qualities of Bodies in General, I now proceed to Particulars: And here I shall not spend Time in reckoning up all the Different Significations of the Word Quality; since what follows will explain, what Sense we use it in: I shall therefore only in short intimate, That several things have been accounted Qualities, Primary Modes of Matter, and Complexions of Qualities mistaken for Real Qualities. which seem rato be Complexions of them; as Inanimal, Animal, Health and Beauty; the last of which seems to be the Result of Symmetry and Complexion, with Agreeable and Delightful Colours. There are other States of Matter also, as Rest and Motion, Size and Shape, usually called Qualities, which are rather to be accounted Primary Modes of Matter. But this concerning Names rather than Things, I shall (waving the usual Divisions of Qualities) treat of them according to the following Division: viz. First, I shall consider them under two Heads; to wit, Manifest and Occult Qualities; the former of which we shall divide gredients of a Body, is evident; since Water Hermetically Sealed, being froze, instead of retaining Fluidity and Transparency, becomes Brittle, Firm, and sometimes Opacous; which Qualities upon a Thaw it again loses. Also fixed Metal, barely by being hammered, becomes brittle; which Quality it presently loses, when heated in the Fire. And Silver, by being hammered, puts on Qualities, which it by no means had when cold; as a Power to melt some Bodies, and to dry others; with several others, which it only acquires, by Virtue of the invisible Agitation of its Parts, put into Motion, by hammering. I might add several Instances of this Kind, but having mentioned them in other succeeding Chapters, I shall omit them here; and pass to The Third Consideration, which hath been proved in the preceding Chapter; which is, That we are not to consider the Effects of mixed Bodies, as the bare Result of the Parts of Matter of such a determinate Texture; but as placed amongst other Bodies, on which they may variously act, and be acted on. But Fourthly, to remove this Objection, we must consider, That the Peripatetic, as well as Chemical Principles, are incapable of accounting for the various Phaenomena of Nature, which the Corpuscular Philosophy hath a greater Advantage in: For neither the different Colours of the Planets, nor the Generation and Perishing of Spots in the Sun, are to be accounted for by the Doctrine of the Peripatetics, nor Chemists; besides several Phaenomena relating to Magnetism, Music, Dioptricks, Catoptrics and statics. And indeed, I should think it not a little strange, that the various Textures, The Difference in Agents and Patients diversify the Actions. as well as Motions of Bodies, would not more sufficiently account for the Phaenomena of Nature, than the Cosideration of Quiescent Ingredients; for as all Natural Bodies, act on one another by Motion; so that Motion is variously determined, according to the different Textures of the Agents and Patients. But to proceed to the Second Objection against the Corpuscularian Philosophy; which is, A Second Objection against the Corpuscularian Philosophy answered. That it is impossible, so great a variety of Qualities should arise from so few Principles, as Matter and Motion. In answer to this, I shall endeavour to show, that it is possible those Catholic Affections of Matter, should be derived from Local Motion; and that those Principles being variously combined and joined together, should afford Phaenomena, as various as any to be observed in Nature. And First; If we allow what is undeniable, viz. That the Tendency of Matter, as to Motion, is different in several Parts of the Universe; it will follow, that by Local Motion so diversified, Matter must be divided into Parts distinct from one another; and consequently, being Finite, must necessarily have a determinate Size, as well as Shape: And since all the Universal Bulk of Matter, hath not its Parts in a constant Motion, some of them, being entangled together, must needs be at Rest. And hence the Primary Affections of Matter flow. But there are yet other Affections of Matter, belonging to the lesser Fragments of it, in Respect of their Situation, as Posture, either Horizontal, Erect, or Inclining, in reference to our Horizon; and also a peculiar Order, in Relation to each other; the Union of which Parts collectively considered, may properly be called Texture, or Modification. And since most Bodies are made up of Parts something Irregular; it is impossible but that there should be Interstices, or Pores left betwixt them. And further, some Parts of Bodies, being very subtle and fine, and easily put into Motion by Heat, or other proper Agents; such Bodies cannot but emit good store of Effluviums. And when Particles of Matter are fitted and adapted, so as to adhere together, they form those similar Bodies, called Elements, which being mixed with one another, constitute Compound Bodies; which being again associated with Compounds, form Bodies, still more Complex; which Compounding and Decompounding of Bodies, The Difference betwixt Mixture, and Texture. may be Properly called Mixture; which differs from Texture, because it implies a Heterogeneity of Parts, which the latter does not. And Lastly, all Bodies, whether Simple or Compound, are to be considered, as placed in the World, as it is now constituted, and ruled by The Universal Fabric of things, as well as the Laws of Motion. The Phoenomena exhibited by the Corpuscular Principles very numerous. From hence it appearing, That Matter is very Naturally diversified by eleven Primary Affections, to which itself being added, makes twelve; we may by Parity of Reason consider, that if such an inaccountable Number of Words, may be made of the 24. Letters; it will not be hard to think, that so many different Modes of Matter may arise from such Finite Principles, as could Reasonably be supposed to result from the various Associations of those ten Letters. And indeed, an inaccountable Number more: since every one of these Principles admits of an Incredible Variety. As first, there may be a vast Variety of Associations in respect of the Figure or Number, or Order of the Parts joined; as in Figure, some may be Triangles or Squares, others Pentagons, etc. There may also another Variety proceed from the Different Shapes and Sizes of the Parts of Matter united; their Figures being either Spherical, like a Bullet, Elliptical, like an Egg, or Cubical, as a die, etc. together with a great many others: Examples of which the Instruments of Carvers, Gravers, etc. afford; those Tools being not only of different Sizes, but also various Shapes. And there is no less Variety in the Degrees of Motion; since Motion may be infinitely different in Swiftness or Slowness, Uniformity or Difformity; as also, according to the different Lines in which Bodies move, as Straight, Circular, Hyperbolical, Ellyptical, etc. as also according to the differently Figured Parts they strike against; to which Causes of Variety, may be added the different Sizes or Shapes of the Bodies moved: as also, the several Degrees of Compound Bodies, and the different Modifications of their Ingredients; and likewise of the Mediums through which they move, as well as the Degreess of Impulse. And the Effects of these may be varied again, according to the different Situation or Determinate Natures of the Bodies they strike against. Musical Instruments afford instances of the various Effects of Motion. And, that Motion is able to produce a vast Variety of Effects, we may learn from Musical Instruments; where according to the Difference of the Air's Motion, arising from the various Vibrations of the Strings, etc. different Sounds are produced; which, as they are more or less coincident cause either Concord's or Discords in Sound. But it would be too tedious to mention all the Diversities which might happen in Qualities, by the various Combinations of our Ten Principles; and therefore, since from hence their Fertility may sufficiently appear, I shall proceed to A Third Objection answered. The last Difficulty raised against the Corpuscular Philosophy, which is, That if the Qualities of Bodies depend on the Size, Shape and Textures of Bodies, all Bodies of the same Colours must have the same Textures; and if the same Textures; the same Qualities in other respects: But we see it is contrary, since the Calx of Hartshorn is insipid, and yet the Volatile Salt of Hartshorn is very strong Scented, and of as strong a Taste: To which a great many more Examples might be added were it necessary. Considerations in order to remove the Difficulty. But I shall rather, since it is not requisite, offer the following Considerations to remove the Difficulty. First, That several Heterogeneous Parts may be lodged in the Pores of a Body, which tho' of a different Nature from the Body itself, yet they may produce some considerable Effects; as in Perfumed Gloves, the Odoriferous Parts are both different in Substance, and have different Qualities from the Leather the Gloves are made of. The Second Consideration is, That Parts of very different Natures may be linked together, not in an Essential Structure, but a Juxta-Position, or Peculiar kind of Composition, and yet afford the same Qualities, notwithstanding their Essential Differences; for invisible changes in some Parts of Matter, may be sufficient to cause new Qualities, tho' the Essential Parts of those Bodies be unaltered; and not only so, but diversified enough to denominate them of different Species. So a Bar of Iron, by being hammered, may feel hot, though there be no visible alteration in the Nature of the Metal by an intense Agitation of the Insensible Parts of it. But to illustrate this Consideration a little further; tho' a Piece of Iron, Wood or Tin, should have sharp protuberant Parts, yet are they distinct Substances, notwithstanding they all agree in that Quality of Roughness; and if those rough Parts were worn off, and the Body endowed with a smooth Quality, yet still would they in respect of their Substance, remain unaltered: And tho' the superficies of Steel, Brass, Flint or Marble should be polished as to become Specular, their Essential Differences would still be the same. And as I took notice before, tho' Air be put into an Undulating Motion by different Instruments, yet if the Motion be raised to the same degree, it causes the same Sound, and produces the same Note. So that Bodies may agree in some Extra-Essential Attributes, and yet be different in their Essential Modifications: To confirm the Truth of which, Heat will afford us an Eminent Example, which may be produced in a Body, by putting its Parts into Agitation, without destroying the Essential Properties of the Body so affected: So that the Essential Nature of a Body may not be concerned in reflecting the Rays of Light, which produce those Extra-Essential Qualities, which are called Colours; since to produce Whiteness in a Body, it is sufficient, that the Surface of that Body be so modified, as to reflect the Rays of Light copiously and undisturbed, whatever the Essential and proper Texture of that Body is. Different- Qualities afforded by Bodies Homogeneous as to Sense. And here it may be proper to take notice, that there are several Bodies Homogeneous as to Sense, which afford different Qualities; as Salt-Peter, becomes fluid and transparent, when briskly agitated in a Crucible; whereas it hath other Qualities when cool, being a hard and white brittle Substance: And the Powder of Alabaster being duly exposed to a convenient heat, acquires several Qualities not different from those of fluid Bodies. So Aqua Fortis although it be transparent and clear, yet if raised in the form of Fumes, it puts on a red Colour. The Third thing I would propose to remove this difficulty is, what hath been several times hinted before, viz. That a Body is not to be considered barely as a determinate Substance, but as a part of the Universe, and placed amongst other Bodies. But Fourthly, As to that part of the Objection, which questions the Corpuscular Principles, in making it appear, why a Body so qualified as to cause whiteness, should have other Qualities which are of no Affinity with it; what hath been already delivered, may be sufficient to remove it, viz. That the Extra-Essential Parts may be so qualified, though the Essential Parts be not altered; which we have more reason to believe, since most sensible Qualities are only relative Attributes, and may result from an accidental Motion, or more than ordinary Laxity or Density of Parts, or some other such like Affections. Several Qualities exhibited by Venice Turpentine To illustrate which, if a Third part of Venice Turpentine be evaporated, we may obtain from it a Colophony of a Reddish Colour, which being beaten small, will lose its Transparency, and be turned into a white Opacous Powder; which with a Moderate heat will again be restored to its former Transparency, Fludity and Colour; into which fluid Body, if one immerges the end of a Quill, something below the Surface, and blows Artificially, it will rise in Bubbles, curiously adorned with vivid and lively Colours; and if in that state you take it into your Hands, it is Viscid enough to draw into Strings; and if put into a Triangular Figure, will like a Triangular Glass, yield a variety of Colours: When cold, it is very brittle, and if moderately rubbed, it is endowed with an Electrical Virtue of attracting Straws: The same Phaenomena will appear upon managing purified Rosin after the same manner. Another Experiment of the like Nature tried upon Putrified Urine. To this I shall subjoin another instance, to show, that a Homogeneous Body, may, by shape or other Mechanical Affections, have different Qualities in respect of our Senses, and the Attributes assigned to it upon that Score: The instance is in Putrified Urine Distilled, the Spirit of which, when it hath by frequent Distillations been dephlegmed, hath a pungent Taste, and swims in a Phlegmatic Vehicle, being also of a very offensive Smell; whose Salts when freed from the Water, are of a white Colour, and are sharp and caustick if applied to an Excoriated Part; besides which Qualities, they likewise make the Eyes water, and cause Sneezing. And in respect of Physic, their Qualities are no less noted, being Diuretic, Diaphoretic, and Specific in Hysterick Fits; when mixed with Filings of Brass, they turn them into a green Colour; yet if mixed with Blue Juices of Plants, they change that Colour for a Green one. They dissolve Copper, yet destroy the Corrosive Virtue of other Acid Menstruums; and precipitate the Copper when dissolved by them: Yet if common Salt be associated with it, this Salt ceases to produce most of the forementioned Effects, and forms a Body very like Sal Armoniac: which change may probably depend on the Motion and Shape of its Parts destroyed, since by Evaporating most of the Liquor, I have found the Salt not only much less Fugitive and Volatile than that of Urine, but the Crystals of a different Figure, being like Combs and Feathers. And These Considerations, together with the Extra-Essential Changes of Bodies, may let us see, that Substances may work variously upon different Senses as well as other Bodies; and those Effects too, may depend on Extra-Essential Changes, which may be wrought in Motion, Shape and Texture, etc. the Essential Modifications of Bodies nevertheless agreeing. So that from what hath been said, the Objection, I hope, will seem less considerable, and not so perplexing as some imagine. And these Three Difficulties I have the rather considered, because they may not only explain, but confirm and illustrate what is delivered in the Chapter before, concerning Forms and Qualities; and may also clear and render more Intelligible, some things hereafter to be related. CHAP. III. Of the Origin of Forms. THE Origin of Forms, Pyrophylies, is one of the most Noble, yet most Obstruse Inquiries in Natural Philosophy; so that the Wisest of the Peripatetics, have either confessed their Inability, or given Explanations of them very insatisfactory. But not to examine all their Various Opinions on this Point, I shall only here briefly consider the Opinion of the Modern Aristotelians, having already in our Hypothesis laid down in the foregoing Chapter, our Thoughts on this Subject. The Doctrine of the Aristotelians considered. The Controversy betwixt us and the Schools is this, Whether the Forms of Natural Bodies be eduted out of the Power of the Matter, and whether they be substantial Entities distinct from Matter? That they are not, appears from what is contained in the foregoing Chapters; and therefore what I shall here insist on is, that the Doctrine of the Peripatetics is to me Incomprehensible; for tho' the Schoolmen make use of an Obscure Distinction, viz. That in producing Forms, the Power of Matter is partly Eductive, and partly Receptive; yet since they deny Forms, to exist in Matter; it is hard to conceive how they should be educed, before existent: And since the Receptive Power, only enables Matter to receive a Form, how can it help to produce it, when the Form must be produced before the Receptive Power can lodge it? It is manifest, that the Body hath a Receptive Power in Relation to the Soul, Forms not educed out of the power of Matter disproved. which nevertheless they allow to have a Substantial Form, yet not educed out of the Power of Matter. It's true, were the Form of a Body a more subtle Portion of Matter, as Spirit is of Wine, the Eductive Power might be considerable; and signify the same, as if it were granted, that the Form is but a Modification of Matter; which would amount to this, viz. That by proper Agents, Matter may be so disposed, as to produce a Body of this or that denomination: As the Form of a Sphere may be conce●…●o exist potentially in a Piece of Brass; because that Metal is capable of being put into such a Form: But this they disallow, because, if it were granted, Forms would be but Accidents. And as for the other way of educing Forms out of Matter, as Spirit out of Wine, that cannot be granted by them; because, than Matter and Form would be the same Substantial Principle diversified by Accidents. But they tell us strange things of the Efficacy of the Agent, which works upon the Matter out of which Forms are to be educed: To which it may be briefly answered, That the Agent can only act as a Physical Agent; and if the Form produced by its Operation, be a Substance not preexistent in that Matter it works upon, and which constitutes the Body, the Form must either be made of some Parts of that Matter, or created de novo; if they allow the former, than the Form is not a Substance distinct from Matter; but if they will not allow it to be made of Matter, it must be de novo, i. e. out of nothing; which being granted, Natural Bodies must be produced by Creation and Generation, and not by the latter only; and it's strange if they allow that a Physical Agent can effect that, which Ancient Philosophers thought too great to be ascribed to God himself. The Aristototelian Doctrine of Forms contrary to Reason. And as for these Reasons, what they say of the Origin of Forms, is to me Incomprehensible; so, that what they deliver concerning Substantial Forms is irreconcilable to Reason: For though they allow these Forms to be Substances, yet they teach, that they depend upon Matter, both in fieri and in esse: i. e. they cannot exist out of the Matter which supports them; which is to give them the Name of Substances, but the Nature of Accidents. Nay, these imaginary Forms as much invalidate the Doctrine of Corruption, as that of Generation; for if a Form be a Substance distinct from Matter, it must exist of itself, as the Soul of Man does, when the Body is dissolved: But they assert, that in Corruption the Form ceaseth to exist; by which means they make it an Accident, and likewise contradict what they commonly hold, viz. That upon Corruption Bodies are resolved into their first Principles; since if what they assert of Forms be true, Bodies are but partly dissolved into their first Matter, and partly annihilated or restored to the common Stock of Forms; which, notwithstanding any thing to the contrary, must be immortal. Arguments alleged by the Schools in defence of their Doctrine answered. But to examine some of the most Plausible Arguments brought by the Schools to evince their Doctrine of Forms: First, they argue thus, Omne compositum substantiale requirit materiam & formam substantialem ex quibus componatur: Omne Corpus Naturale est compositum Substantiale, Ergo, etc. In which, Syllogism for Brevity sake I shall deny the Minor, because nothing in Nature is composed of Matter and a distinct Substance, but Man. The Second Argument they bring, is, that if Substantial Forms were denied, all Bodies must be Entia per Accidens; to which it may be answered, that there is no such Necessity, since Matter, Figure, Texture and Motion, ordinantur per se & intrinsice, to make up natural Bodies. Another Argument which they allege is, That if there were no Substantial Forms, there could be no Substantial Definitions; which comes to no more, than that if we don't grant some things which are not in Nature, we shall want a Foundation for our Definitions: And indeed if we must define Natural Bodies by Imaginary Forms, which we know not, it is better to exchange Substantial for Essential Definitions, grounded on the Essential Differences of Natural Bodies themselves. Their Physical Arguments considered. These Arguments for Substantial Forms being examined, I shall briefly consider the Physical Arguments usually alleged for the proof of them. The first is, the Spontaneous cooling of hot Water; an Action usually attributed to the Power of the Substantial Form; which might be plausible, were it not otherwise to be explained; for Bodies esteemed cold, having their Parts in a less Agitation than the Natural Juices about the Sensory, cause that Sensation; but when the Parts of that Water, by the heat of the Fire, are put into a Violent Motion, stronger than that of the Parts of Matter about our Sensory, it becomes hot; which hot Water being removed from the Fire, and the Agitation of its Parts being diminished, it returns to its just Temperature: To effect which, a Substantial Form is no more requisite, than when a Ship is put into a violent Motion in a Storm, there is required a Substantial Form to stop its Motion upon the ceasing of that Storm. And in opposition to Substantial Forms, it may be likewise considered, that Water in upper Rooms in hot Climates, will be kept warm, and in Nova Zembla, in the Form of Ice, merely by the Temper of the Air, in spite of the Substantial Form. Another Argument urged is, that Matter being indifferent to all Accidents, it wants a substantial Form to link the Accidents requisite to every Particular Body together. To which it is answered, that the World being now made and constituted, the Phaenomena of Nature depend on one part of Matter acting on another; so that especially fluid Bodies frequently change their States, being altered by the several Seasons of the Year, and Temperature of the Air, which is evident from the different Effects it hath on Weather-Glasses. So that the Accidents observable in most Bodies, depend on Agents and Efficient Causes, which produce in Matter what in the Precedent Chapter we call an Essential Form: And there is no need of a Substantial Form to keep those Accidents together, since they will continue in the same state, till some other Agent works on them, which is strong enough to destroy and change the Texture and Form of that Matter; which Agent, the assistance of a Substantial Form being not able to resist, the Body in spite of the Peripatetic Doctrine must be changed; an instance of which we have in Lead, which (tho' when melted, it returns to its pristine state upon cooling) if it be long continued upon a Violent Fire, will be turned into a reddish brittle Glass, and lose all its former Qualities; and retains those new acquired ones, till some powerful Extrinsic Agent, cause a fresh Change. On the contrary, Oranges, Tamarinds, Senna, and several other Bodies, retain the same Qualities, when gathered and removed from the Soul of the Tree, and without the influence of its Form, which they had before whilst growing: And the colour of Snow soon perisheth, notwithstanding its Substantial Form, its Texture being altered by a Dissolution. The Parts of a Body may adhere without the help of a Substantial Form. But there is still another Argument generally alleged in favour of Substantial Forms; which is, that without them, the various changes observable in Bodies, and the adhering of several Parts of Matter united into one Totum, would be unaccountable. As to the first Part of this Argument, it is easily answered, since Local Motion variously determined, is able to effect considerable and various Changes in Bodies; an Instance of which (besides what hath been said in the first, and the preceding part of this Chapter) we have in Tallow, which by the Mechanical Effects of Fire, exchanges Heat for Coldness, Fludity for Firmness, and instead of Whiteness, puts on Transparency. And besides the Changes which are caused by the Action of one single Quality in an Agent, as Heat; the Operations of Bodies, proceeding from the Texture of the whole, are various, as appears by Factitious Vitriol, which is made of Iron and a Corrosive Menstruum, yet hath all the Qualities of Natural Vitriol. And as to the Second Part of the Argument, viz. That the Parts of a Body could not be united into one without a Sustantial Form; I answer, That a Connexion of Parts conveniently figured is sufficient; as when a Pear is grafted on a White-thorn, or a Plum is inoculated on an Apricock; there is a Union of Two different Forms merely by a Connexion of the Parts of Matter, and the Parts grafted or inoculated, receive Nourishment as naturally, as if they were supposed to be joined by a Substantial Form, to a Stock of the same Form and Texture with themselves. Another Instance of Union by a Connexion of certain figured Parts, we have in Glass, where the Particles of Sand are linked together with the Saline one's, by the help of Colliquation, and the violent Action of the Fire. But to conclude; I am not ignorant that it is alleged in favour of Substantial Forms, that they render Natural Philosophy much more perfect, and that it would be very imperfect without them; which comes to no more, than that if we must not explain things difficult by things unknown, we must be imperfect; where I think the Imperfection is not at all remedied; for should it be asked why Jet attracts Straws, or why Rhabarb is a Cholagogue, and the Answer should be, by reason of their Substantial Forms; it would be all one as to say, by I know not what, because those Forms are unknown. Being therefore in things purely appertaining to Natural Philosophy, unwilling to believe what is not intelligible, I shall leave the Doctrine of Substantial Forms, to those that have clearer Heads than myself, and shall rather proceed upon Intelligible Principles. The Form of a Body is its Essential Modification. I shall therefore briefly intimate what hath been delivered before concerning our Notion of Forms, viz. That the Form of a Body is its Essential Modification; and tho' Matter at the first Beginning of things, had both Form and Motion from the wise Creator of things; yet now the various Forms of Bodies depend on the Effects of Local Motion, which divides, and variously transposes, and so altars both the Textures and Forms of Natural Bodies, tho' I say, at the Creation, the Parts of Matter were guided by a Supreme Power, so as to convene into an orderly and well contrived Fabric. CHAP. IV. Considerations concerning Subordinate Forms. as they are usually held by several Learned Modern Philosophers. IT is usually held by several Modern Philosophers, That besides the Specific Form of a Body, The Notions of Modern Philosophers, concerning Subordinate Forms, there are several Subordinate Forms in Determinate Parts of it, subservient to that which is the Common Form of the whole Substance; and which, upon the Dissolution of a Body, become Specific Forms themselves; the Specific Form which presided over them before, being destroyed: As when in a Living Animal, the Soul, which is the Specific Form of that Animal Body is separated from it, the Forms which were before lodged in every Part, as subordinate to that, become the Specific Forms of each Part: But tho' Sennertus ingeniously alleges the Specific Virtues of Plants in favour of this Doctrine, yet we have reason to repute them invalid Arguments; since we see, That several Flowers retain their Natural Colours and Smells, and for aught we can perceive, the same Virtues with which they were endued when growing, after they were gathered. Considered, and examined. But since this Doctrine hath been made use of, to corroborate their Notions of Substantial Forms; I shall make it appear, that what they atrtibute to Subordinate Forms, may be explained by the Corpuscular Philosophy. In order to which, I shall consider and observe, First, That the Technical Word Form is usually made use of, to signify some conspicuous Phaenomena of a Body, upon the Abolition of which it is said to change, or deposit its Form. Secondly, That those Parts, or Substances usually held to be the subject of Inhesion to a Subordinate Form, are Organical; and tho' some appear as to Sense Similar; yet are they composed of Parts very different: As Vitriol, which tho' to Sense it appears to be a Similar Substance, yet it is by Art discovered to consist of Saline Parts, united with a Metalline Substance: And Rhubarb, which instead of that Specific Form it had whilst growing, according to their Doctrine, exerts its Subordinate or Substantial Form, when laid up for use, retains Virtues, which are different from each other; as a Styptic Virtue, when the Purgative is extracted: So that there is no Reason but that it should have Subordinate Forms, agreeable to each of these Qualities, distinct from those which are called Forma Mistionis, by the Schools: But further, we may observe in an Almond, which though when gathered, it loses its Vegetative Form; and that which was before Subordinate becomes the Specific Form of it: yet there is no Reason why we should deny Forms Subordinate to that, since by a bare Pressure, it discovers itself to consist of an Oil and an Insipid Substance, both of which have Forms distinct from that of the entire Fruit: To these, Observations to prove Subordinate Forms. I shall add two Instances more; the first of which is in Sulphur Vive, which by being kindled under a Bell, yields oily Parts which are spent in a Flame, and Saline Corpuscle, which, being condensed by the Moisture of the Air, adhere to the sides of the Glass, and constitute a Menstruum violently corrosive, which will afford a dry brittle Salt. The Second Instance is in Cinnabaris Fossilis, which is a Substance compounded of three Forms, very distinct from each other; as that of Mercury, and Sulphur, which is also a Compounded Substance: From all which it appears, that there are in most Concretes, besides the Substantial Forms of the whole, Forms Subordinate to those, belonging properly to the Parts of those Compound Bodies. But, A Compound Form what. Thirdly, That all the Ingredients of a Compound by Uniting, make one Form, upon the Union of which all the Effects of that Body depend, is evident in Gunpowder, the Action of that Compound depending on the Concurring and united Effects of Charcoal, Nitre, and Sulphur: So that Fourthly, Tho' a Compound acts by Virtue of its Composition, and ad modium unius; yet each of its Ingredients retain their particular Attributes, as well as their Modifications, which distinguished them from other Bodies before that Composition was made: and this is evident from what some of the Aristotelians writ concerning the Life of an Embryo; viz. That an Embryo hath a Vegetative and Sensitive Life, before that of a Man; where the Vegetative and Sensitive Souls, pre-existent to the Rational, are not destroyed, but only deposed by the Succession of a Superadded Soul; which become the Specific Form; from whence it Naturally follows, that there are Forms which in respect of others are only Preparatory, and dispose the Matter modified by them, to receive a more exquisite Stamp, or a more perfect Form; which, if it be not added, those ruder Forms, are nevertheless Specific in respect of those Bodies they are the Forms of. But tho' I make use of these Arguments, I would not be thought to adopt altogether what these Men teach, In what Sense the Soul may be said to be the Specific Form. having elsewhere explained, in what Sense, according to their Doctrine, the Souls of Living Bodies may be said to be their Forms, by observing the Difference betwixt Animating and Natural Forms, as to the Manner of their Informing the Bodies they belong to. As the Soul is not the sole Architect of the Body, nor do the Properties of the Body flow from it, tho' in other Bodies the Compound Form, as well as Qualities, depend on the Forms of the Ingredients of that Body united. In what the Specific Forms of an Animate Body differ from those of an Inanimate. And indeed the Properties of a Body are so far from flowing from the Specific Form, where the Soul alone is esteemed so; that in Brutes, as well as Plants, several Qualities remain undestroy'd, after the Form is destroyed; as Shape, Colour, and Virtues, etc. And tho' it be held by some, That there's a Forma Cadaveris, that keeps the Parts of a dead Body united, and preserves their Qualities entire; yet, since it is only held as necessary, to support the Peripatetic Doctrine, we shall not dispute it; but shall only say, That the Fabric and Connexion of the parts of a Body, are sufficient to preserve the Pristine Qualities of it from Dissolution, till the Internal Agitation of the Juices breaks that Texture: which is apparent by what hath been observed in very cold Countries, as Russia and Sweden; where the dead Bodies are for several Months kept unburied, and uncorrupted: and in Aromatic Plants, there is an undeniable Argument, since after the Vegetative Soul is destroyed, they continue uncorrupted for several Years. The Forms of the Ingredients of a Compound truly esteemed Forms. But to determine whether the Soul be the sole true Form of an Animate Body, is not our Design at present; and therefore I shall only bring an Instance or two to show, That the Forms of the Simple Ingredients of Compound Bodies are as truly Forms, as those of a Complex Body. The first is, That the Spring of a Watch is as truly a Spring before it is made a Part of that Watch, as after; and as truly hath its Form: And tho' Copper by Corrosive Spirits be turned into a Vitriol, and consequently the Form of Copper, in respect of that Vitriol, becomes a Subordinate Form; yet it is as truly one as that of any other Body. 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, hard to be determined amongst Natural Bodies. And tho' Aristotle attributes to Forms 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, yet it is a Matter of Difficulty to know what Form is most Noble; since Pearls, which are of the greatest Value, being prepared in the Form of a Magistery, are of little Value to them that only wear them; tho' by a Sick Man the latter is more to be prized. Fifthly, But tho' it be so difficult to distinguish Valuable Forms, from those of less Esteem; yet there may be allowed some Distinction amongst Subordinate Forms, in as much as some belong to Similar, and others to Organical Parts. Sixthly, amongst the Parts of Plants, or Animals, there may be some Parts so modified, as to put on the Form of Seminal Principles, which upon the Dissolution of that Body, may act as such, in actuating and guiding some Parts of Matter so, as to convene into Infects, etc. Seventhly, Upon the Dissolution of the Specific Form of a Body, the Body is to be considered as beset with other Substances, which may act upon it; as the Sun, Air, or some other Agent; by means of which the Seminal Principles may be put into Action, or new Forms may result, from new Contextures of that Matter. Sennertus' his Opinion agreeable to the Corpuscular Philosophy. These Observations being premised, I shall endeavour to show, That what the Learned Sennertus delivers, is agreeable to the Corpuscularian Philosophy. I agree then with the Learned Sennertus, That the Faculties of Plants and Animals, depend not on the Materia Prima, and Vegetative or Sensitive Soul; nor on the Form of mixed Bodies, considered barely as such; but that there is something else requisite to produce that Variety of Effects, observable in Specific Medicines. But tho' I allow these things, yet I disallow their Way of Explaining them, as well as a great deal more which they assert; as, That Subordinate Forms act under the Superintendency of Specific Forms; Subordinate Forms act not under the Superintendency of the Specific Forms. forasmuch as we may as easily attribute the Effects of a Compound Body, to the mixed Action of the Compounded Ingredients, as to the Subservient Actions of Subordinate Forms, which united will have an Action in common, and proper to their Complex Modification; it being different from what each of those Ingredients would produce separately. As in a Balance, the Scale, which by its Specific Gravity ought to tend downwards, is raised upwards, by the Addition of a Weight in the other Scale. So an Arrow, by the Spring of a Bow, is forced to fly in a Line, different from what its Specific Gravity would incline it to, and with greater Violence. And as a Clock, whose Parts concur to the forming of an Engine, proper to produce such Effects, as usually are produced in that Machine, does not act by Virtue of a Superintendent Specific Form; but the Parts are set on Motion, and move Mechanically by the help of Weights; so, several Subordinate Ingredients, may have a Joint Effect, each of those Body's cooperating, and modifying each other's Actions. Likewise Gunpowder, acts not by Virtue of a Specific Form, superintending Subordinate ones, but Mechanically, by Virtue of the Joint Effects of its Ingredients; which is evident, since the Effects of the Composition are so different from what the separate Ingredients would produce; and as from hence it appears, that the Efficacy of it depends on its Mechanic Texture; so, to make it appear, that the Ingredients were but slightly mixed, I boiled the Powder of it in Water, and, evaporating the filtered Liquor, obtained Cristals of Salt-Petre, the black stuff remaining in the Filtre, being insipid, and inflammable like Sulphur: And this black Matter being boiled in a strong Lixivium, so as to dissolve the Sulphur, the Sulphureous Liquor will run through a Filtre, leaving the Charcoal behind; into which Liquor if an Acid Spirit be dropped, the Sulphur precipitates in the Form of a white Powder. But to illustrate our Doctrine of Forms and Qualities a little further, I shall add, That a blue and yellow Powder being mixed in a just Proportion, produced a green Colour: which did not happen, because those two Ingredients were subservient to a Predominant Form; but because they both being joined made a Compound Impression upon the Eye. And likewise in making Sublimate or Vitriol; all that is requisite to enable them to produce Effects proper to such Bodies, is, that the Parts should be in a proper manner contexed and modified together; and then, they are not only capable of performing what is usually ascribed to them, upon the Account of their more specific properties; but some, which are not different (as Vomiting, and Purging, etc.) from those Effects, which are said to be produced upon Vegetables, upon the account of a Superintendent Form. So that tho' the Operations of Compounded Substances depend on the United Texture of Subordinate Forms, Neither are the Actions of Compounds wholly to be attributed to their Union. yet, as I have before taken Notice the Actions of those Bodies, are not wholly to be attributed to their Union; since upon the Dissolution of that Contexture, each Body hath its determinate Form and Virtue; as when the Ingredients of Gunpowder are again separate; or as when a Rose loses its Specific Form, by being taken from the Tree: But, To conclude this Discourse, we shall again take Notice of what we have before hinted at in the beginning, viz. The unfixt use of the Word Form, and that a Body is said to be of this or that Form, upon the Account of a very few Qualities: If then the Form be nothing but a Congeries of Accidents, it may, by proper Agents, lose that Form, the Subordinate ones still remaining undissolved; The Modifications of Bodies twofold. till a more powerful Agent destroys them too: (so that a Body may have a twofold Modificatiod:) As for Instance, The Spring of a Watch, may, by being put into the Fire, lose that Elastic Virtue; yet nevertheless the Substance is Iron, and retains Qualities proper to such a Substance. Again, another Instance we have in a Rose, which when it hath lost its Faculty of receiving a Nutritious Sap from the Tree, yet it retains other Qualities, which depend on the Texture and Modification of its solid Parts, the former being only Qualities, in respect of the Specific Form; but the latter, the Result of its Contexture. To illustrate this Notion a little further, I shall make use of the following Comparison, viz. That as a Mill, which is an Organical Machine, performs what belongs to it as such, as long as it is supplied with Water; so a Plant is enabled to effect several things, whilst actuated by a Vital Spirit: And further, as a Mill upon the Consumption or Congelation of that Water, still retains the same Parts it had before, so do the Parts of a Plant, tho' the Soul ceases its communicative Virtue. And to continue the Parallel further, as the Constituent Parts of a Mill are not destroyed, tho' the Faculty of Operating as such be lost; so neither is the Water, but only by reason of Congelation, or Evaporating in the Form of Exhalations, ceases to coexist in a Form fit to turn the Mill: So tho' a Plant or Flower be lopped off, and retains the same Texture of its solid Parts, yet when it ceases to be watered with a continual supply of Sap, the Sap is only dispersed in the Air, or intercepted, and spent in some other Part of the Tree: From whence it appears, that nothing at all perishes, but only the Manner of Union, and the Particular Modification of those Parts of Matter cease; so that those solid Parts are no longer fitly adapted to be nourished by those Fluids. Which Instance may serve to illustrate our Doctrine, tho' there be considerable Difference betwixt the things compared, inasmuch as a Plant hath not always that Aptitude to be again actuated as the Mill hath. But there are some Instances, which may render the Difference less considerable, if we consider that the Rose of Jericho, which tho' for several. Years gathered, and withered, is so far refreshed by Water, as to seem but lately gathered: And I have observed, that tho' a Plant of Aloes had several Years hung near the Ceiling of my Chamber, yet it was by the use of a convenient Liquor, so far renewed, as to perform several things, which are usually the Effects of Life and Growth. And the like is confirmed by what may be experimented in Wasps, which, tho' drowned in Water, will yet recover Life by the Heat of the Sun. The Qualities of a Body whose Specific Form is destroyed, depend not on the United Action of the whole Ingredients But to wave needless Illustrations, I shall proceed to observe, That tho' a Body hath laid down its Specific Form; yet the Qualities remaining, are not always the Result of the united Subordinate Forms; but depend sometimes on the determinate Forms of Particular Parts of that Body, tho' the Union be such as to preserve the Structure, as to Sense, unalter'd; as appears when an Extract is drawn out of Rhubarb, or the Juice of Oak-Bark is extracted by Water, the Remaining Substances, tho' as to outward appearance the same, New Qualities may be added upon a Dissolution of a Speficick Form. retain not their Specific Virtues. Besides, upon the Abolition of Specific Forms, several new Qualities may be added to a Body, which it had not before, by the Influence of external Agents: As when Musk results from the Action of some External Body upon Flesh: For not only the Seminal Rudiments, latent in Bodies that have undergone a Change, exert themselves; but several outward Agents, to which those Bodies are exposed, do, by agitating and altering the Textures of that Matter, promote such a Favourble concourse of Circumstances, that Noble and very Exquisite Forms, may result from their Union and Contexture. As a Limestone, being Physically changed by the Influence of Congruous Particles, when exposed to the Air, will yield Salt-Petre, genuine and inflammable. And I have often observed an Efflorescence upon certain Marcasites, agreeable in both Colour and Taste, as well as other Operations, with Vitriol, which could be nothing but the Effect of outward Agents, changing the Texture of those Parts, which lay open to the Air for some time. The Modidifications of a Body may be twofold, first in respect of this Specific Form, secondly in respect of its own Parts. But to wave there things, I shall illustrate a little further, what I just before hinted concerning a twofold Modification of Matter, viz. the Relation it hath to a Specific Form, and that which is the mere Result of Texture amongst its own Parts: what I shall offer, is, That some things are attributed to the Soul or Specific Form, which may be effected by the mere Subordinate Association of Parts, promoted by a mutual Concourse of Natural Agents; as the Excrements may be voided when a Man's dead, or Fruit may be ripened after it is gathered, without the assistance of the Expulsive Faculty of the Soul in the former, or the Perfective in the latter. Agreeable to this, the Inquisitive Oviedo relates a Story to the Emperor Charles the Fifth, of a Fruit in the West-Indies, called Anana's, which are gathered as soon as One is ripe, the rest being kept in Chambers to acquire Maturity afterwards. And the Learned Josephus Acosta relates the following Account of the Fruit of a Planetree to the same, viz. That they usually gather it when green, which being laid up in a Vessel mixed with a certain Herb, gradually ripens. But the Diligent Piso tells a Story, more to our Purpose, of those Brasilian Plants, called Pacoeira, and Bananiera; for concerning the Fruit he says, Continentur plerumque in Vno Ramo, quatuordecem aut sedecem numero, ut it a una Planta, proferat septuaginta aut octuaginta, qui subinde Virides avulsi, nunc in Aedibus, nunc in Navibus suspenduntur, donec justam maturitatem & flavedinem consequantur: And he also says of the Boughs, when lop'd off, Ramus autem ille fructibus onustus, interea dum illi maturescunt, augetur, floresque semper protrudit, ex corpore illo foli●ceo, etc. And it is not less remarkable, that Onions, and such like Fruit, as well as Potatoes, will shoot of their own accord, tho' suspended in the Air. But not here to take Notice how far these things may result from the Exertion of Latent and Seminal Principles, I shall rather observe, That several things usually ascribed to the Soul, may result even from the Texture of the Body, concurring with external Causes; as the Hair, or Nails will grow considerably for a long time, after the Body is dead. * A Cessation of Vital Functions upon Death, no Arguments of the Soul's Superintendency whilst living. And tho' by the Espousers of Sennertus his Opinion, the Cessation of the Vital and Animal Functions upon Death, are looked upon as strong Arguments, That the Soul is the Agent, which effects whatever is acted in the Body; yet I conceive it depends on somethings very precarious; since notwithstanding what is manifest to us, the Cessation of those Faculties may depend on the internal Organization, which may in some measure be destroyed; Since the Body consists of Parts, not only solid, but soft; as the Brain, and also liquid, as the Humours; a right and convenient Coaptation of which is required to preserve Life, considerable Changes in the Humours, being enough to obstruct Circulation, on which Life so much depends. Thus in Palsies, tho' there be no visible Change; yet by an Indisposition, either in the Humours or Vessels, the Parts become void of Sense as well as Motion: And even Sleep itself, so altars the Disposition of our Bodies, that Odours and Sounds are not perceived by a sleeping Man, tho' nothing externally obstructs the Operation of the Soul, which lodges in the Body; and what considerable Alterations in the Humours may be effected, without our Perception, may be urged, from the Effects which Thunder hath upon Wine, in turning it into a Vinegar, sour and uninflamable. The former Doctrine of Subordinate Forms, applied to Inanimate Bodies. But to render what I have said of Subordinate Forms, more intelligible, I shall lay it down in certain Propositions, without making long and tedious Excursions, applying it chief to Inanimate Bodies: And first I shall consider, 1. That the signification of the Technical Word Form, is indeterminate; since it is not agreed what is enough to determine, what Forms Bodies are of; it being not only disputed, whether Water, by being froze, loses its Form or not; But further, several Bodies have no particular Forms assigned to them; as Ink, Gunpowder, Beer, Coal, etc. Nay, some Bodies considered in different Respects, may seem to have more Forms than One, as in Vitrum Saturni, which is made of Lead, it may be doubted, whether it hath the Form of a Metal or Glass; since it hath a great many of the Qualities of Both, as Fusibility, Transparency, and Brittleness; and will, contrary to common Glass, dissolve in Aqua Fortis, yield a sweet Solution, and may be reduced into a Malleable Lead by Fire; so likewise Amel, whose Ingredients are calcined Tin, together with Salt and Sand, and some Copper, will again yield most of the same distinct Ingredients; yet the Compound had not all the Properties belonging to these Bodies. But, The Nobleness of Forms, hard to be distinguished. II. It is a Matter of Difficulty to determine the Nobleness of Forms. This is not only evident from Examples before given, but several others; as Glass of Antimony, is more apt for some uses than Crude Antimony, and vice versa. Again, it hath been formerly a Dispute, and may be a Doubt still, Whether the Powder resulting from Gold and Silver precipitated, be a Nobler Metal than Gold; of which were a Spagerical Physician, and a Goldsmith to judge, the Former would value the Powder, as much as the Latter would the Gold. Again, tho' Silver Soder be the Result of Silver, alloyed with Copper or Brass, and of very great use; yet it may be questioned, whether it is not by that means rendered less valuable. And tho' a Plant be petrified, and for that reason valued as a Rarity; yet is that New Form in itself less Noble than the former. The most Noted Qualities of a Body, denominate its Form. III. Tho' several Alterations are made in Bodies, by a Recess or Access of Qualities, yet they retain the same Denomination, and are said to have the same Form, by reason of some Eminent Quality or Use; which is proper to them. For which reason Vitrum Antimonii is called so, because it hath the Fusible and Transparent Qualities of Glass; tho' it, in other Respects, besides its Vomitive and Purgative Properties, hath Qualities different from Glass. So all Unctuous Bodies, as Oil of Almonds, Olives, etc. are called Oils, because Fluid, and not apt to be mixed with Water; yet there is a great deal of Difference betwixt them, and Empyreumatical Oil of Guajacum or Box: So likewise several Substances of very different Effects, are reckoned amongst Salts; because they readily dissolve in Water, and are very sapid; so that the Word Form, seems to be applied to Bodies on the account of some Metaphysical Conceptions, and in respect of some General Use; rather than Physical Forms, by which Substances of the same Form, are said to be of the same Specific Nature and Virtue. From whence it may be thought that several Substances are generally Classed together, as they are alike States of Matter, rather than agreeable Forms: As Water and Wine may be turned into Ice, or Tallow and Mineral Concretes, may become of the number of Substances which constitue Flame. The Action of several Compounds depends on the Union of their Parts. iv That by Compound Bodies, several Effects will be produced, upon the account of the Union and Joynt-Action of their Ingredients. These Operations, by the Schools, are said to be done Actione Communi; as when a Man disputes viuâ voce, the Rational Soul concurs with the Vocal Organs, to the Forming of Syllogisms: Or, to use a plainer Instance, as a Bullet acts on a Plane, by Virtue of its whole Specific Gravity, tho' it touches the Plane but in a Point; the other parts acting on it by the Intervention of that: Or as in a Pair of Scales, the whole Substance of a Man, and all that he hath about him, presses upon the Scale, tho' he touches it but with his Feet. But to use an Instance of the Concurrent, or Actio Communis, of an Organical Body; the Effects of a Compound Body, are like that of a Watch, where if any Part be wanting, the Complex Action so much depends on the Common, and Joynt-Action of the whole, that the Action of the whole is destroyed. Inanimate Bodies have Subordinate Forms. V It is agreeable to Reason, to admit of Subordinate Forms, in Bodies Inanimate. Against this it is objected, That one Body cannot have two Forms. To this it may in short be answered, That tho' a Body can have no more than one Adequate Form; yet being a Compound, it may have several, which are Subordinate to, and Parts of that; as the Parts of a Watch have each their own Forms, which are Subordinate to the Form of the whole. A Second Objection is, That a Body having a Complete Form, whatever is Concurrent to it, makes it Ens per Accidens. To this it may be answered, That according to the Schools, the Soul and Body, which have each separately distinct Forms, being joined, make Vnum per se, and not per Accidens; and the Rational Faculties, which are its Accidents, are said to make Vnum per se: So that thence, by Parity of Reason, tho' a Congeries of Accidents, concur to the Forming of a Body, yet the Operation and Property of the whole United, being one, it may as well be said to be Vnum per se. Add to this, that the Peripatetics have not scrupled to teach, That the Forms of Elements, are not destroyed by being mixed, yet they hold each of the Bodies made up of them, to be Vnum per se. But it may be further answered, That tho' a Form be complete in itself, yet the Form resulting from the Union of another with it, may be far more Noble, and perform things much more curious than before: As when Sulphur and Nitre are added to Charcoal; or when a Spring is added to the other Parts of a Watch, where by the Addition of these Forms, the pre-extent are not destroyed, but improved; the whole, in each Composition, making one Compound Form. A Superadded Form may modify the Actions of Subordinate ones, without destroying them. VI Sometimes a Superadded Form is Accidental to a Pre-existent; yet it modifies the Operations of it, without altering its Nature. As a Needle, which hath its Form considered as Steel, besides its Figure as a Needle, and by being touched with a Loadstone, acquires several other Properties; as to attract others, and instead of its Indifferency to move any way, regulates its Motion, so as to point North and South; of which Properties it is again deprived by being drawn upon the Pole of a powerful Loadstone. But that we may more clearly understand, how a Superadded Form modifies the Actions of a Body, we need but reflect on the Parts of a Watch, from whence the Forma Totius proceeds; where we may see, how the Spring, by being bend, acquires a Tendency to expand, and how the Wheels moderate that Expansion: From whence we may gather how the Parts of a Body, which united, make the Forma Totius, concur in superadding several New Qualities to the whole. So a piece of Lead is Vitrifyed by the Action of the Fire, by which Action the Parts, which before were pliable, become brittle; and being otherwise ranged as to Situation, give way to the Rays of Light, and becomes Transparent: And Salt-Petre, by the Addition of Coal and Sulphur, instead of burning by degrees, and leaving an Alkalizate Salt behind it, flashes all away at once. Compound may act by Virtue of one single Ingredient. VII. Besides the Actions of a Body, which are specific, in respect of the whole; it may have several Operations depending on the separate, and particular Properties of an Ingredient. This may appear from what hath been delivered above: But to make it more clear, I shall again intimate, what hath been before delivered, viz. That the Parts of a Watch, retain several of their Pristine Qualities, when put together, as they did before: To which another Instance might be added, from what is elsewhere said of Gunpowder. To which it may be added, That several Ingredients in Physical Compositions, retain their own Qualities, tho' the Composition hath in General a Particular Effect upon the account of its Mixture. As for Instance, Ambergris retains its Smell, as well as Aloes its Taste, when made up into Pills with other Ingregredients; and Opium likewise its Soporifick Qualities, tho' mixed with so great a number of Ingredients as those of Venice-Treacle. Another Example we have in the Precipitate of Gold and Mercury by Heat, which tho' it hath a red Colour, different from both the Ingredients, yet the Mercury retains its Salivating Faculty. The most noted often esteemed the Specific Form. VIII. That is often called the Specific Form in several Natural Bodies, which is not the Presiding, but only the most Eminent. To prove this, we are to consider, what hath been already observed: As First, That the Signification of the Word Form, is made use of Arbitrarily, and without sufficient Distinction. Secondly, That Forms are only Respective, and the Result of a Determinate Coexistence of the Parts of Matter. Thirdly, That they are attributed to Bodies, upon the account of some particular Qualities; as Unctuousness in Oils, etc. or some particular Use. Pourthly, Agreeably to these, a Body must be endued which several of those Qualities, upon the Account of which Bodies are referred to different Classes. As in Vitrum Antimonii, in which besides those Qualities by which it is referred to Glass, it hath a Vomitive and Purgative Faculty, by which it is brought into another Class in Physic. Fifthly, It is not requisite, that these Forms should depend on one another; since neither the Vomitive nor Purgative Faculty depend on the Form of Glass, they both being inherent in the Calx, before it was Vitrifyed, and would be preserved, tho' the Glass, without an Addition of other Matter, should be turned into a Regulus. Sixthly, To these Observations, we may add, That the Qualities of Bodies, are said to be less or more Noble, in respect of their different Uses: As in Glass of Antimony, tho' the Glass may be taken for the Noblest Form by an Artist, yet it's other Antimonial Qualities are more Eminent amongst Chemists and Physicians. Seventhly, From these Considerations we may gather, that the most Predominant Form is not always that which denominates the Form of a Body; but sometimes that which is most Eminent, that is, most regarded. Some are rather Concurrent Forms, than Subordinate. IX. The Forms just now mentioned, are rather to be esteemed Concurrent, than Subordinate. And indeed, where the Denominating, or most regarded Form, may be so varied, they rather seem Concurrent than Subordinate, in respect of the Body, whose Attributes they are. So that the Subjection of some sort of Forms, seems very difficult to be explained. And indeed we are so apt to mistake Names for Things, since by only denominating some Bodies, which have Particular Operations, we are apt to attribute what is the sole Effect of Modification, to that Metaphysical Conception, which we have of an Airy Form, rather than to the Body considered as a Physical Agent, endued with a Mechanical and Adventitious Texture. And it is so far from Appearing that there is any thing of Supereminency, or Dominion of one Form in all the Operations of a Compound Body, that in some Simple Bodies, the Specific Form is not in the least concerned in the Effects of them; as Water will scald by Virtue of its Adventitious Heat, which is contrary to those Qualities attributed to its Form as such. And so Springiness may be added to, or taken away from Silver, without altering the Specific Form of the Metal; nor does the Form of a File, considered as Metal, affect what is attributed to it, upon the Account of those Asperities: Nor is the more than usual Hardness the Product of the Substantial Form, but an acquired Temper given it by the Smith. It would be an easy Matter to add several other Instances: But to conclude; Tho' the uncertain Signification of Terms, hath made the Foregoing Discourse the more Difficult and Dark; yet I hope it may serve to detect some received Errors, and promote a truer Theory concerning these Matters. CHAP. V Experiments and Thoughts about the Production and Reproduction of Forms. Bodies distinguished into Spaecies how. IT was not without Grounds that I intimated in the preceding Chapter about Qualities, that Bodies are in a great measure distinguished into several Species by a sort of Tacit Agreement; there being as yet, no Diagnosticks sufficient to distinguish the several Species of things, but they are rather taken for distinct Species, by being known by such Names, than any true Characteristics. As for instance, some well skilled in the Writings of Aristotle, hold, that Water and Ice are not esteemed distinct Kind's of Bodies, they both having the same Nature; yet Galen not without Reason, favours the contrary Opinion, since they differ both in respect of Fluidity and Firmness, as well as Transparency: Besides, Ice and Salt beaten together, will freeze other Liquors, whereas Water and Salt will not; where there seems to be difference enough to denominate them Two distinct Species of Bodies, as well, as that Must, Vinegar, Wine, Spirit of Wine or Tartar, should be esteemed so; or that a Chick should be thought different from the Egg which was hatched. Yet some Aristotelians have been very doubtful whether the Natures of them be different or not, as also whether Clouds, Hail▪ Rain or Snow differ in Specie from Water▪ tho' the Writers concerning Meteors usually treat of them as different. And if so small an Accident as Mo●●●● o● whatever distinguishes Wind and Exhala●●●… is enough to entitle them to distinct Species of Bodies, a Greater Right may be presumed 〈◊〉 Paper and Rags, Glass and Wood-Ashes, should be esteemed so too; as also Soap, Sugar, Gunpowder, etc. For it is not a sufficient Objection that most of these Bodies are Factitious; for the present state of a Body, denominates its Species, however it came by that Nature; as the Salt which is made in the Isle of Man, by the Sun acting upon the Sea-water, is as much Salt, as that which is artificially made by the Heat of the Fire, by boiling Sea-Water in Chauldrons; and Silkworms and Chickens hatched by the heat of Ovens or Dunghills, are equally as much Silkworms or Chickens, as those produced by the heat of the Sun, or warmth of a Hen. The Products of Art, the Effects of Nature. Besides, the Objection, that most of the forementioned Bodies are Factitious, is less valid, since they seem equally performed by Nature, the Artificer being only concerned in putting Natural Agents together, which take the same Measures in causing their Effects, as if they had casually been brought together by Chance: As in Chemistry, the Agent which is Fire, operates upon the Subjects it hath to work upon as Fire, and not as it is barely an Instrument of a Chemist; and therefore tho' the Application belongs to the Chemist, the Action is as much Natural, as the Productions of Aetna or Vesuvius; where by the internal Action of the Fire, Stones are Calcined, and Metals not only colliquated, but Metalline Flowers and Ashes dispersed about the adjacent Parts. And I am not without Probability inclined to believe, that several Minerals as well as other Bodies, which lie near the Centre of the Earth, are rather the Productions of Subterraneal Fires, changing the Textures of other Bodies than that they have lodged there, since the first Creation of things; for we see, that Lead becomes Minium, and Tin Tutty, in a very small time, and the Fumes of Sulphur, uniting with those of Mercury, convene into that delicate red Mass called Vermilion, which hath so far the similitude of a Mineral, that it hath been called by the same Name of Cinnabaris: So that we may easily conceive, how in the Bowels of the Earth, certain Mineral Fumes penetrating and uniting with a stony Concretion, Minerals may be form: From whence it may appear, that a Congeries and Union of Accidents, is as sufficient to discriminate the several Species of Bodies, as the imagination of Substantial Forms. The Artificial Production of Vitriol, correspondent to the Natural. But to illustrate the Mechanical Origin of Forms, we may take notice of the Artificial Production of Vitriol, which is so like the Natural, that it makes us able to guests what Measures are taken in the Natural Production of it. And since Vitriol is not a mere Salt, but rather (to use a Chemical Term) a Magestery, it is requisite to observe, that according to the sense of that Word, it is not prepared by a Separation of Principles, but by the changing the Form of a whole Body, by an Addition and intimate Union of a Saline Menstruum: Agreeable to which Notion it is to be noted, that an Acid Spirit, and a Metalline Substance, may be drawn as well from Artificial as Natural Vitriol; and consequently both must be equally natural Vitriols in the strict sense of that Word. But these are not the only Characteristics of the Natural Agreement of Factitious and Natural Vitriol; since Vitriol of Mars, whether prepared by Oil of Vitriol or Spirit of Salt, hath both the Colour, Transparency, Brittleness, aptness to Fusion, and Styptical Taste, with the Vitriol of Marchasites; as also several other Qualities, as to turn an Infusion of Galls into Ink; a Vomitive Faculty, when taken in a small Dose; as also to be endowed with Crystals of very Curious Figures, and a Disposition to run per Deliquium, as Guntherus Belichius hath observed common Vitriol made use of in Germany to have. And here we see, that the same Qualities may arise from the Union and Association of Two Ingredients, which are to be found in Common Vitriol; without the Incomprehensible force of Imaginary Substantial Forms, or a Generation of a Form distinct from the Ingredients and their Essential Modification; or a Texture of Parts of convenient Shapes and Sizes: Neither is there such an Intimate Mixture, as the Schools imagine, of these Two Ingredients, but a Juxta-Position and new ranging of their Parts in respect of Order and Position: Which is evident, since by Distillation the greatest part of the Vitriol may be drawn off, leaving the Metalline Substance behind; and that most of its Qualities depend upon the Position of its Parts is plain, since through a good Burning Glass, the Sun Beams will so alter their Order and Texture as to turn it red. CHAP. VI Doubts and Experiments, concerning the Curious Figures of Salts. The Figures of Salts to be accounted for, with the help of a Plastic Power. THO' I am not willing to acquiesce in the Doctrine of Substantial Forms, since to me they are Incomprehensible; Yet I am as forward to own, That I acknowledge the Admirable Wisdom of our CREATOR no less, because He hath thought fit that the Changes and Alterations in Matter, should depend on Accidents easy and intelligible, at least with less Difficulty to be conceived, than the incomprehensible Doctrine of Substantial Forms: And tho' the Curious and Delicate Shapes of Salts, be Generally used as Arguments of the Great Plastic Skill of Substantial Forms; yet I must own, I think them very slight things, compared with Organised Bodies; and therefore I would not have it inferred, That because the Figures of Salts may be accounted for, without the Assistance of Plastic Powers, that therefore the Bodies of Animals may. That Substantial Forms are not necessary to the Production of those Curious Figures in Salts, I am induced to believe; First, Because a Concrete of no less Curious Figured Parts, than other Vitriols may be made by a bare Connection of Metalline and Saline Bodies. Secondly, because according to the different Quantities of Liquor, or the space of Time they shoot in, their Figures vary: According to which Agricola, lib. 12. p. 462. de re Metallica, speaking of the Cords that are immerged into Vitriol-Water, for the Crystals to stick to, says, Ex his pendent rests lapillis extentae, à quo Humor spissus adhaerescens densatur, in translucentes atramenti sutorii, vel cubos vel acinos, qui Wae speciem gerunt. Crystals obtained from an Alkaly. I remember also, that having a long time thought that the Method usually taken in preparing Alkalyes, such as Salt of Tartar, etc. was the reason, why they are gathered in the Form of Calx; I took care to dissolve Alkalyes well purified in Water, slowly evaporating it, till crusted over, with an Icy Crust; which being preserved entire, lest they should want a sufficient quantity of Liquor, to give them liberty to move, in order to their more Curious and Congruous Coalitions, I continued them in a moderate Heat for some time, and then breaking the Crust, I had a variety of figured Lumps of Crystalline Salt; transparent, and not much unlike white Sugar-Candy. From Oil of Vitriol, and a Solution of Sea Salt. Likewise having several times distilled Oil of Vitriol, and a strong Solution of Sea-Salt together, till the Matter left behind was dry; that Salt Substance, when dissolved in Water, filtrated and evaporated, would shoot into Salts, of Figures differenr, according to the various Proportions of the Ingredients; yet nevertheless tho' sometimes in the same Glass the Salts would be of different Figures; yet would they be more tightly figured, than those of Vitriol often are. And from a Mixture of Spirit of Wine, and Spirit of Nitre, digested long together, From a Mixture of Spirit of Wine, and Nitre. I have got Crystals much like in shape to Crystals of Salt-Petre; and I have obtained Plates of Crystals, made up of solids, very curiously shaped, and so congruously adapted, as to make a very plain Surface, much different from what I have elsewhere mentioned from a Solution of Silver in Aqua fortis, or Spirit of Nitre; when I have ordered it so, that it should shoot leisurely. Thirdly, I have several ways made it appear, That Insensible Parts of Matter of various, tho' very curious Shapes, guarded with plain as well as smooth sides, will convene into Bodies differently shaped. And tho' Blood, Urine, and hartshorn, might probably have their Substantial Forms destroyed by the Fire; yet forasmuch as the Saline Parts, with which they are impregnated, are of the Figures just now mentioned, in the Liquors they have been exposed, to shoot leisurely; I have observed several Masses, the surface of some of which were Plains, very curious and delightful, and the Figures of others exactly Geometrical: And stillatious Acids, as well as the Bodies they are appropriated to dissolve into Crystals variously figured, according to the Nature of the Menstruum, or the Bodies it works upon; as I have experienced with a Menstruum which would dissolve Gems, and likewise with Coral dissolved in Spirit of Verdigreece: For which Reason, when I tried whether the Shapes of the Particles of Silver, dissolved in Aqua fortis, would dispose them, Salts obtained from a Solution of Copper. without a Coagulation with Salts, to shoot into smooth and flat Concretions; I observed, that Part of the Solution being diluted with distilled Rain-water, and a Copperplate immersed in the Liquor, after it had remained there a while, Clusters of Metalline Bodies, devoid of Transparency settled about it, joined together in Plates very thin, yet very glossy and flat, the Edges of the largest, being prettily shaped. From Gold. And that the Particles of Gold are apt enough to associate with Congruous Salts, and to compose Bodies of determinate sizes, I have observed in Crystals, afforded me by Gold, dissolved in Aqua Regis, and being preserved in a cold place, till the superfluous Moisture was evaporated: And from the Parts of Gold divided by a stronger Menstruum, so minutely as to be capable of being sublimed, I have obtained Crystals much of the same shape, tho' different in size from one another. And I remember, having long since dissolved several Saline Bodies together in Water, by a gentle Evaporation, they have yielded Concretes, different in shape from each of the Ingredients; but it oftentimes is very difficult to associate them, because some are disposed to Crystallize sooner than others: As may be observed in purifying Barbary Nitre, from the common Salt it is mixed with; and as Agricola, lib. 12. de re Metallica, takes Notice, where a Vitriolate Substance, and that from whence Allom is drawn, are joined together; yet Venetian Borax, Crystals obtained from Venetian Borax. tho' made up of several Salts, yields Crystals of very Regular and Geometrical Figures: And the Caput Mortuum of common Aqua fortis, which consists of Bodies disagreeable in Nature, by frequent Solutions and Coagulations of their Saline Parts, yield Salts of very curious Figures, as Triangles, Rhomboids, Hexagons, Prisms, and Pyramids, composed of several Triangles, meeting in a Vertical Point, and as curiously shaped as Cornish Diamonds. But the Acquisition of new Shapes, by being compounded, is not only practicable in these Grosser, but even in Chemical Salts, which affect one another, with an Ebullition; because in that Conflict, the Volatile Spirits unite and lose much of their Force; so that being less apt to fly away upon Evaporation, Salts obtained from Spirit of Urine, and Nitre, etc. they form curiously shaped Crystals; as I have Experienced with Spirit of Urine and Spirit of Nitre, Spirit of Sheep's Blood and of Salt, Spirit of Nitre and Oil of Vitriol, and likewise with Spirit of Salt and Spirit of Urine; the last of which shows, how much Compound Figures are owing to the Union of the Particles of the Ingredients, of which they are composed; the Spirit of Urine and Salt, affording Concretes different from those of Oil of Vitriol and Spirit of Urine; the shape of the first being like that of a Comb, whose Teeth stand out on each side; or like a Feather, the Crystals on each side being so much inclined: Crystals of a like Figure to which, From Soot and Sal Armoniac. arise from a just Proportion of Soot dissolved, and coagulated with common Sal Armoniac. Fourthly, To confirm what I have above delivered concerning the Origin of Vitriol; and also to make it appear, That the Figure of its Parts depends on the Texture of its Ingredients, I shall add another Particular, which is, That having compared the Composition of Artificial Vitriol, I thought it might reasonably be ranked under the same Species with the Natural: To which I shall subjoin, that having also considered, that Oil of Vitriol, and Spirit of Salt, were improper Menstruums to dissolve several Metals, I made use of Aqua fortis, which with Copper, made a Curious Vitriol; and with Silver, it afforded Crystals shooting into thin Plates; and with Lead and Quick Silver, it yielded Crystals far more thick, and differently shaped from each other. Now if from hence it appears, That the Curious Figures of Salts, generally alleged as Arguments of the Necessity of Substantial Forms, depend merely upon Texture; why may not the more Ordinary Phaenomena of Nature, since it is manifest that Matter, and a Congeries of Accidents, are sufficient to account for what is usually attributed to Imaginary Forms? Neither can I see Reason, why Arguments grounded on the Qualities and Effects of Bodies, esteemed factitious, may not be sufficient to show us, what may be ascribed to the Mechanical Affections of the universal Mass of Matter; since it is not agreed how factitious shall be distinguished from that Species of Body, called The Productions of Nature. In favour of which Gunpowder is no despicable Instance; where by a bare Mixture of Nitre, The Ingredients of Gun Powder. Charcoal, and Sulphur, without the least shadow for the Pretence of a Substantial Form, a Body is produced, of Effects more prodigious, than any of Nature's Production: Nor can Nature produce a more Noble Concrete than Glass, which is but the Product of Matter, brought together by Art; where in less than an Hour, an Opaque Body becomes transparent, and acquires several other Qualities, for as much as appears to Sense, without the Addition of any other Body; which yet by another change, in a trice, may make a Substance not Glassy, but Opacous. * Substantial Forms not necessary to Discriminate Bodies. Nay, the Aristotelians themselves allow, That there may be slight Changes in Matter, so as to distinguish Genus', without an Introduction of Substantial Forms; as in Coral, which in the bottom of the Sea is tender, and grows like a Plant, yet when hardened in the Air, it is by several Eminent Writers, classed amongst Stones: And indeed, its Calx is very much unlike the Ashes of Plants, being apt to be corroded by Vinegar, as Lapis Stellaris, and several other Mineral Stones are. And a thing equally to be admired, is to be seen in Sombrero, an Island in the East-Indies, near Sumatra, according to Sir James Lancester; who relates a Story of a Worm, which is transformed into a Tree; and that again into a Stone, much like white Coral: And Piso, in his History of Brasil, vouches many Witnesses for the Transformation of Animals like Grass-hoppers, into Vegetables. Likewise Michael Boym, a Jesuit, affirms, That he saw in the Island Hainan, in China, Crabs, which pulled as out of the Water, were immediately petrified. But, Pyrophilus, that I may draw to a Conclusion, I shall only further add, to what hath gone before, Oil of Vitriol turned into Allom. that Remarkable Experiment of Helmont's, which is that Oil of Vitriol may be turned into Allom, by the Fumes of Mercury: To which may be added another Instance, presented us in the Production of Salt-Petre: For if on the white Salt, afforded by Solution of Pot-Ashes, Spirit of Nitre be poured, Salts obtained from Spirit of Nitre and Pot. Ashes. till they cease to ferment, that Mixture will yield Crystals endued both with the Shape, and other Qualities of Nitre. CHAP. VII. Experimental Attempts concerning the Redintegration of Bodies. HAving already to confirm the Origin of Forms, as intimated in our Hypothesis, alleged the Measures taken in the Productions of Forms, I now proceed to illustrate it from their Reproduction, which might prove the stronger Argument of the Two, could it be clearly made out; because to Re-produce a Body, whose Substantial Form hath been destroyed, may argue, that a Form is only a Modification of the Parts of Matter of which a Body is composed, in such order in reference to each other, as is requisite to produce such Properties: Whereas were those Parts otherwise placed, they would make up a Body of a different Nature; which would be again of the nature of the former were the Parts of which it consists associated in their former Order. But tho' an Adequate Redintegration of Bodies Chemically Analized were impossible, by Reason of some Dissipated Parts; yet such a one as is possible, may be sufficient to our Purpose; which is the Experiment concerning the Reproduction of Salt-Petre. But Experimental Attempts of this kind being very difficult, all that I shall do at the present, is, to represent that Difficulty. And An Attempt to reunite the Parts of Amber. First, we shall do it by relating our Success in an Attempt to dissipate and reunite the Parts of common Amber; for having put Four or Five Ounces of Amber into a Glass Retort, by a gentle Heat it began gradually to melt and bubble; and after the Operation was ended, we found in the Receivers half the weight of the Amber, consisting of a Mixture of Volatile Salt, Spirit, Phlegm and Oil; and in the bottom of the broken Retort, we found a Cake of Matter very black, yet so smooth, that nothing could be finer Polished; so that it might very well have supplied the place of a Looking-Glass; which, when it was broke, the Fragments were accompanied with a more than ordinary Lustre. All which divided Parts of Amber being mixed in a Glass Body, to which a Blind Head was luted, and placed in Sand, the Fire being by Accident increased, the Fumes raised the Vessel out of the Sand, which falling, the Top of it was broke, by striking against the side of the Furnace, and the Fumes flew away. The remaining Matter was very like Tar, but would not Tincture Spirit of Wine; tho' with Oil of Turpentine, it would make a Blood-Red Balsam. The whole Process being again renewed, and some Accidents happening, we could not finish the Experiment. An Attempt to reunite the Parts of Roch-Allom. But notwithstanding the Difficulty of Trials of this kind, having once drawn what Quantity I could of Phlegm and Spirit from Roch Allom, and poured it again upon the Caput Mortuum, after some time, some Parts were so associated again, as to form several curiously figured Crystals: An Attempt to reunite the Parts of Vitriol. And though Vitriol may seem a Body unapt for such Experiments, yet I once drew from blue Vitriol a Phlegm and Spirit together, with a heavy Oil, which being divided into several Parts, the red Caput Mortuum was divided into an equal Number, one part of each of which being mixed over Night, in the Morning I found several Grains of pure Vitriol upon the Surface of the Matter; which I again found upon the Mixture of another part of the Powder and Liquor, only more in Quantity; and this Experiment was also confirmed by a Third Trial. As also of Antimony and Oil of Vitriol. To these I shall add, what happened upon the digestion of powdered Antimony, with a double quantity of Oil of Vitriol: For having drawn from it a little Liquor, together with a considerable Quantity of combustible Antimonial or Antimonio-Vitriolate Sulphur, the Caput Mortuum remaining in the Report was light and friable, and upon the upper part white like common Wood-Ashes; the rest being like a Cinder. Whereupon we exposed it to the Fire, in a Retort of Glass well Coated, and fitted with a Receiver; and after some time separating the Vessels, we found very little Sulphur sublimed; and not the least Antimonial Quicksilver, but the Caput Mortuum was united into a Mass of black Antimony, covered over with white transparent Glass. From whence we may infer, that Antimony generally abounds with more Sulphur than is requisite to constitute that Mineral; though in this Experiment we might suspect, that part of it was turned into Glass, by the Loss of the Sublimed Sulphur. Another to reunite the Parts of Vitriol. But amongst all my Experiments of the Redintegration of Bodies, the following was the most successful; for having distilled from several Ounces of Turpentine in a Glass Retort, a considerable Quantity of Transparent Liquor, and a dry brittle Caput Mortuum, I reduced the Caput Mortuum into Powder, which by that means was turned from a Red, to a pure Yellow Colour; and being mixed with the Liquor, was form into a Red Balsam; which, by a continued Digestion, began to lose that Colour, so that the Powder being wholly dissolved, it could not be distinguished from Laudable Turpentine. CHAP. VIII. Experiments concerning the Origin of Qualities and Forms. HAving in some of the foregoing Chapters, given a short Scheme of the Principles of the Corpuscularian Philosophy, for the better understanding our Experiments concerning the Productions and Changes of Particular Qualities, I shall now lay down such Natural Phaenomena as induced me to take up such Notions, in which, not Art but Nature discovers her Operations. EXPERIMENT I. An Experiment to illustrate what hath been delivered concerning Forms and Qualities. The First I shall begin with is, what occurs in hatching of an Egg. And. First, we are to consider, that in a Prolific Egg, by the same Reason, that Bones and Membranes are called Similar Parts of an Animal; the Liquor of the Yolk, as well as the White, is to Sense, a Similar Substance, though by Distillation several Substances may be drawn from them. Secondly, That by beating the White of an Egg well, it loses much of its Tenacity, and becomes a fluid Body; in which Agitation, there is only a Mechanical Alteration of the Texture of the Body. Thirdly, That the Rudiments of the Chick, lodged in the Cicatricula, are nourished only by the White, till it becomes a great Chick; the Yolk being reserved as a stronger Nourishment, till the White is spent, and the Chick is able to digest it; and in effect the Chick seems to be furnished with Head, Wings, Beak and Claws, before the Yolk is touched. Lastly, It is not a little to be admired that so Soft and Similar a Liquor as that of an Egg, should be in so short a time, changed into a Chick, endowed with Organical Parts of different Fabrics; and Similar one's different in Texture very much from one another; besides the Liquors contained in the Solid Parts, being as different as the former, and endowed First, With new Qualities, as Colour, Taste, Odours, Heat, Hardness, etc. Secondly, Qualities distinct from Sensible ones, as Fludity, Consistency, Hardness and Flexibility, etc. Thirdly, Occult Qualities, as when Birds or Parts of Animals, afford Specific Medicines, or at least most Noble ones. But Fourthly, since some may Object, that these Parts are form by the Plastic Power of the Soul, and that a Chick is not a Mechanically contrived Engine, we are to consider, that let the Plastic Principle be what it will, yet still, being a Physical Agent, it must act after a Physical manner; and having no other Matter to work upon, but the White of the Egg, it can work upon that Matter but as Physical Agents, and consequently can but divide the Matter into Minute Parts of several Sizes and Shapes, and by local Motion so variously contex them, as is requisite to produce an Animal of this or that Species; though from so many various Textures of the Parts form, there must naturally arise such different Colours, Tastes and Consistencies, and other Qualities, as we have taken Notice of: For we are not here to consider so much, what is the Agent or Efficient in these Productions, but after what manner the Matter they are made of, is affected in producing them: To illustrate which, we may observe, that a Man who is to frame a Building, or some curious Engine, though he may by the help of Reason and Art, skilfully contrive his Materials, yet he can but move, divide, transpose and contex the several Parts, into which he reduces the Matter assigned. And that the Soul of a Hen, does not any more contribute to the forming of a Chick, is plain; since we are assured, that multitudes of Eggs may be hatched merely by the regulated Heat, either of Ovens, or Dunghills: Whence it easily appears, That the Plastic Power, no otherwise contributes to the Formation of a Chick, than by guiding the Parts of the White, put into Motion by the external Heat; so, that they may associate after a manner necessary to produce an Organical Chick. EXPERIMENT II. Water may, by altering its Texture, put on New Forms. Water, tho' a Homogeneous, Diaphanous, Fluid Body, devoid of Colour, Taste and Smell, etc. may, by altering the Texture of its Parts, acquire Attributes different from these: This is evident, in the Growth of Vegetables, when nourished even by simple Water, in Bottles; where I have observed, that Crows-foot, after six months' Growht, weighed above three times as much as before it was put in. But not only Crows-foot, but several other Plants, own their Substance to the Particles of Water, altered in Texture, as Spearmint, Marjorane, Raphanus Aquaticus, and Ranunculus: From whence we may infer, that the same Particles of Matter which compose Water, may, by having their Parts differently modified, produce several Concretes, endued with different Qualities, as Firmness, Volatility, Colours, Smell, and Taste; together with other Specific or Occult Qualities: Yet it is to be admired, that so insipid a Body as Water, should be converted into a Juice so caustick, as that of Ranunculus, or one so inflammable as Oil, which may be drawn by Distillation from Plants, only nourished in Bottles. OBSERVATION III. All Plants may be nourished by one and the same Substance. It is usually believed, That Plants by the Faculties of a Vegetative Soul, select and suck in a Juice, appropriated to each; rather than that they are all nourished by one Juice differently modified in that Plant: But the Latter will easily appear, if we consider, what happens in Grafting and Inoculations; for if a Pear-Tree be Grafted into a White-Thorn, the Aliment sucked in by that Root, will be so altered, as to yield Nourishment to a Pear; Fruit much different from that of the White-Thorn: The same is evident in Inoculations, where the Sap, selected by the Root, is so altered in the Bud inoculated, that the same Sap, which in the Genuine Branches of the Tree, constitutes one sort of Fruit, is turned into another, in those springing from the inoculated Bud. And here it is further Remarkable, That not only the same Juice yields various sorts of Substances in different Plants, but even in the same Tree; where the Skin of the Fruit differs from its Flesh, and that from the Stone, and all of them from the Substance of the Tree; not only in Colour, but several other Qualities; as the Blossoms of a Peach, have a Purgative Virtue, which is not in the Fruit: And Garcias ab Horto affirms, That the Seeds of solutive Cassia fistula, are Astringent: An Account not unlike to which we have of certain Kernels of a Fruit, much like a White Pear-Plum, by Mr. Lygon, in his History of Barbados, p. 67, 68 Five of which worked a dozen times upwards with him, and twenty times by Stool; yet by taking away a thin Film, which divides the Kernel into halves, the Nut is as sweet as a Jordan Almond, and has no sensible Operation: Which Relation is also favoured by Monardes', under the Title of Fabae Purgatrices, where he speaks of a Purgative Fruit, brought from America, from Carthagena, and also from Nombre de Dios. And Vincent le Blank, in his Survey of the World, p. 260. Part. 2. gives an Account of a Golden Apple, as bitter as Gall, containing Five Kernels, of an equal Bigness with Almonds, whose Juice is sweet; and he also relates, That of a thick Film, which encompasses the Nut in the Shell, they prepare an Excellent Sweetmeat. OBSERVATION IU. Further Instances in Cheese. We have also an Instance, how Matter may be altered, by a Variation of its Texture in Rotten Cheese; which differs from the Sound, both in Colour, Taste, Smell, and Consistence. In which likewise, by a good Microscope, we may perceive Clusters of Animals, endued with Parts very differently modified, and Qualities little different from Occult ones. CHAP. IX. A Continuation of Experiments concerning Forms and Qualities. EXPERIMENT I. MIX a convenient Quantity of Camphire, grossly beaten, with Oil of Vitriol, and when it gins to dissolve, and, by shaking the Glass, to mix with the Oil, it will first tinge it with a Yellow, and afterwards a Colour not much different from Red; which Tincture will be so deep, as to render the Clear Oil Opacous. And from the Ingredients perfectly mixed, if in just Proportion, may be obtained a Liquor void of a Camphire Smell; yet by the sole Addition of Fair Water, the Mixture will become Pale, and the Camphire will again associate, and form a floating Combustible Body as before dissolved, and renew its Odour. Several Phaenomena the Result of a Change in Texture. From the Phaenomena of this Experiment, may be drawn several Instances to our Purpose. I. That a Light Body reduced into Parts, conveniently Figured, may be mixed with a Body heavier than itself; so that Gold, the heaviest of Bodies, may float in a Liquor, if its Parts be dissolved, and rendered minute enough by Aqua Regis. From which two Observations we may Learn; That the Textures of Bodies, as well as the Rules of hydrostatics, are concerned in determining, whether Bodies will sink or swim. II. That several Colours may be produced, by a Mixture of a Colourless Liquor, and a White Concrete. III. That those Colours may again be destroyed, and the former renewed by Water, which can neither afford the Colour it reduces Camphire to, nor destroy that of the Liquor. iv That a Light Body emerges out of one much lighter, which did not in a heavier Liquor, which the Mixture was before the Addition of Water; which may be an Argument against the Schools concerning Mistion; since some of them assert, That, in Mistion, the Elements depose their own Forms, and put on new; whereas the Camphire had not its Form destroyed throughout the Process; but still retained its own Qualities in a Disposition to be again united. V It is to be admired, That Odours should depend on so slight a Texture, that Camphire, by a bare Separation of its Parts, should lose its Scent, and upon the Mixture of a Body void of Odour, should again recover its Smell; and that so slight a Texture, as that of the Oil and Camphire, should, as to Sense, wholly for a time alter the Qualities of the Latter: And that several of the preceding Phaenomena, are caused by the Particular Texture of the Liquors, made use of to exhibit them, is manifest, because if Camphire be cast into Spirit of Nitre, well dephlegmed, it will not afford those Phaenomena, which it does with Oil of Vitriol. And when to the Red Mixture, abovementioned, two or three parts of Spirit of Wine, were added instead of Water, no such Changes succeeded; but the whole Mixture, with its Accidental Colour, was dissolved by it, being in Colour much like Red Turbid Wine: So that the Colour of the Mixture was wholly owing to the Mixture of the Oil and Camphire, and depended on their Union; which is further confirmed, because when we added a sufficient quantity of Water to that Turbid Liquor, it presently deposed its Colour; and the Particles of Camphire immediately emerged in the Form of a white Powder. But there are other Phaenomena, which by a prosecution of this Experiment, the Mixture afforded us: For, VI Having kept the Mixture moderately warm in a Glass Retort, and distilled it; the Liquor drawn off had a Smell, unlike both that of the Camphire, and also that of the Mixture: And the Ingredients united in this Mixture, were both. Transparent, in the Sense that Fluid and Solid Bodies contused are said to be so; yet the Remaining Mass, not only became Opacous, but of a very Black Colour: some Parts of it, being not unlike polished Jets; which is the more Remarkable, because Camphire Chimically handled, usually ascends in White Flowers, leaving behind them a Caput Mortuum of an Agreeable Colour. VII. The last Phaenomenon this Mixture afforded us was, That tho' Camphire be a Body very much disposed to dissipate, and fly away; yet by the Association of the Oil, it might be kept together, so that the Caput Mortuum abovenamed, was able to endure a pretty hot Fire in the Retort, before it was reduced to that Pitchy Substance, lately taken Notice of: And further it was Remarkable, That Part of the Substance being taken out of the Retort, and kept in a Red-hot Crucible for half an Hour, it afforded a considerable quantity of Black Brittle Matter, without the least Smell of Camphire: Fixedness and Volatility are so much varied by Texture. EXPERIMENT II. Diversities of Qualities depend on Variety of Textures. Amongst the various Experiments, which might be produced to prove, That the Diversity of Qualities depends on the various Alterations of Texture; I shall instance those afforded me in Copper and Silver, by the Intervention of Sublimate; where we shall have a Considerable Number of Changes, made by the Recess, Addition, and Trasposition of the Insensible Parts of Matter. First then, Having put a Pound of Venetian Sublimate, grossly beaten, into a Glass Retort; we threw in Copper Plates, an Inch broad, and about as thick as a Grain of Wheat; so that the Ascending Fumes, might by Compulsion act on the incumbent Metal: Which being done, we placed the Retort in a Sand Furnace; and having adapted a small Receiver, we continued a Gradual Fire, for seven or eight Hours; and at the last increased it to a considerable degree, which was as high, as the Furnace would permit: The Effects of which Operation were the following. 1. Very little Liquor was carried over into the Receiver, but about ten Ounces of Sublimate was crusted over the Neck of the Retort: The Retort contained two Ounces and a Quarter of Running Mercury; and what was to be admired was, the Acid Spirit, uniting with the Copper, left the Mercury unaffected. 2. When the Fire was increased, the Matter, beginning to Melt in the Retort, made a Noise not unlike to Vitriol, when brought to a Fusion, in a Calcining Pot: which Circumstance constantly accompanied this Experiment; whereas the same Experiment being again tried, we scarce could find either in the Retort, or Receiver, the least Running Mercury. 3. The Lump of Metal in the Retort, was heavier by more than two Ounces; some of the Plates being too thick, and yet retaining their Shape and Malleableness; the others, being changed into a Brittle Lump, like a piece of good Benjamin, which, when broke, was of divers Colours, and almost Transparent. 4. But this Lump, being divided into smaller Pieces, and exposed to the Air in white Paper, in a Night's Time it was Coloured like Verdigreese on the outside; which by its longer continuance in the Air, penetrated deeper; yet the Paper which it stained, was tinged with a Green, inclining to Yellow. And here we may take Notice of the strange Subtlety of the Air, which altered some of these Fragments so, that they were covered over with a Powder, like Viride aeris, notwithstanding they were shut up in a close Box. 5. Here I shall observe, That several Copper Plates, off which Sulphur had been drawn, had not their Shapes altered in the least; but were coloured over with a white Silver colour, which penetrated the whole Substance of them, being much more glorious within, than on the Surface of the Metal: so that we suspected the Sublimate to be adulterated with Arsenic; but that it retained its Malleableness; which Arsenic usually takes away. 6. We thought it more considerable, because the Venus of the Copper was so unlocked, that the foremention'd Transparent Substance, would melt like Rosin, and burn with a lasting Flame, if laid on a Red-burning Coal, or held to a Candle, much like the Flame of Sulphur, only more Green. To these Phaenomena, afforded by Sublimate and Copper, I shall join some, observed in the like Experiment, with Sublimate and Silver. We put ten thin Silver Plates into a well-coated Retort, with double the weight of Sublimate upon it, which when Sublimed, the Sublimate ascended into the Neck of the Retort; in which was to be found several Portions of Revived Mercury: In the bottom of the Retort was a Lump of Matter, which could scarce be separated from the Glass, but was brittle and of a Pale Yellow, and much of the same weight with the Metal. In the middle of the Lump, were contained pieces of Silver very brittle, but not totally dissolved: This Rosin, as that of Copper, when moistened by the Air, was in 24 Hours covered over with a Greenish Dust; but whether it were the Result of Sublimate working on the Copper, which Silver is generally alloyed with, or on the Compound Metal, I will not dare to determine: Yet it is usual for Painters to make a sine kind of Azure of Silver, by corroding it with Saline Bodies: All that I shall add to be observed in this our First Trial, is that this Rosin, when cast upon hot Coals, continued flaming for a considerable Time, the Colour of the Flame being very like that of Copper. But for a Second Experiment, we made use of an Ounce of Refiued Silver Laminated, and cast upon double its quantity of Sublimate; which, by the violent Force of the Fire, being partly melted, we found in the Retort a Lump of Matter, which in some places next the Glass, was covered with a thin Plate of Silver, the remaining part of the Metal, (except some small pieces) being dissolved into a Substance, neither like Silver, nor any other Metal or Mineral. In which process it is strange, that so fixed a Metal, should, by an Addition of a Fourth Part of Matter, be so altered in its Qualities; as also, that a Mass of an Amber or deep Amethystine Colour, (some of whose Parts on he upper Superficies were of a light Yellow, which on the lower ended abruptly in a colour not far from a Black one) should be the Result of a Mixture of two white Bodies: Nor is it less to be admired, that a Body Transparent like Amber, should be made of so Opacous a Body as Silver, mixed with a white Powder; and that Silver, instead of the Qualities of a Metal, should become a Friable Body; and when cut with a sharp Instrument, like Horn; as also, that it should be changed into a Body, apt to take Flame at a Candle, which before was difficult to melt. These Experiments being tried; To show how much these Qualities depended on the Particular Textures of Bodies, I took two distinct Urinals, and put Gold finely Laminated in one, and Refined Gold in the other, with a triple weight of Sublimate to each; which tho' raised in a Sand-Furnace, altered neither of them: But in these Experiments, being forced to make use of a Sand-Furnace, I could not employ a Fire so strong as I could have wished for, which might in some measure alter the Phaenomena, which our Experiment might have otherwise afforded: But, Before I leave this Experiment, it may not be improper to give the following Advertisement, viz. That a further Improvement might be made of this Experiment, by making use of several kinds of Sublimates; which might easily be obtained by raising several other Bodies up with Sublimate. Of which I shall add an Instance; for having Sublimed a Mixture of equal Parts of Sal Armoniac, and Common Sublimate, in Urinals placed in a Sand-Furnace, I obtained a Sublimate different from the former; for Salt of Tartar dissolved, being dropped into the Common sort dissolved in Water, turned it into an Orange-tawny Colour, but changed a Solution of the other into a Liquor white like Milk. To try the Effects of this New Sublimate, we Sublimed it with a Mixture of Copper in the Retort, in the bottom of which was to be found a Cupreous Rosin, which would, as the other abovementioned, turn to Verdigreese: But it is very Remarkable in this Experiment, That the Sublimate was tinged with a Blewish-Green, by Particles of the Copper carried along with it; and also, that in the Receiver, was found near an Ounce of Liquor tinged with Copper: From whence it appears, That this opened the Texture of Copper, more Powerfully than the other Preparation of Sublimate. The same Method is not requisite to produce a Body, provided the Result be of the like Texture. EXPERIMENT III. To make it appear, That there are several Ways to produce the same Qualities in Bodies, provided the change of Texture be the same, I shall instance a Particular Experiment made with what the Alkymists call * The Preparation of Luna Cornea. Luna Cornea. Having dissolved Refined Silver in Aqua fortis, and Filtrated the Solution, we dropped Spirit of Salt into it, till the Liquor would no longer curdle, which being Filtrated through Cap-Paper, we dried the Remaining Substance, washed and cleared from its Salts, whilst it remained in the Filtre, by running fair Water through it; when dried, it was melted into a Mass in a Viol, covered with Ashes, and being preserved in Fusion for a little time, afforded a Luna Cornea. But if instead of dropping the Salt upon the Solution, the same Method just before laid down, be taken with the Crystals yielded by that Solution moderately evaporated, they will shoot into Diaphanous brittle Crystals, much different from those of other Metals endued with several other Qualities, the Quantity of Salts interposed betwixt the Parts of the Metal weighing but a third part of the Compounded Mass. In the Foregoing Process, the following Phaenomena may be taken Notice of, to our present Purpose: First, That tho' Acids, and Alcalyes have generally contrary Effects, yet both Oil of Tartar per Deliquium, and Spirit of Salt have the same Effect in Precipitating Silver; which evinces, That the Precipitation of Bodies is neither to be attributed to Alkalyes nor Acids, considered as such; But to a mutual Interposition and Texture of the Parts of the Matter, whereof those Bodies consist. Secondly, It may be observed, That Bodies Diaphanous, and void of Colour, may be changed into Opacous, and white ones. Thirdly, That a white Powder may be turned into a Yellow Body, in some measure Transparent. Fourthly, That Silver by a Mixture of Saline Parts, may be rendered so apt to Fusion, that it will melt like Wax at the Flame of a Candle. Fifthly, It is remarkable, That tho' either of the Ingredients of this mixed Body, would readily dissolve in Water; yet the Composition would not. Sixthly, It is to be admired, that a Body in Texture, not unlike a piece of Horn, should be the Result of an Association of two rigid Bodies: Wherefore to be satisfied, That the Alteration depended on the Texture of Parts of the Ingredients, I made use of the Oil of Vitriol, instead of Spirit of Salt, and found that the Concrete resulting from an Union of that with the Crystals of Silver, differed from the former, it being much more brittle, and easily divided into Parts. But what is more remarkable is, That a Body compounded of one of the most Bitter, and another of the sowerest Taste, should be itself insipid, or of a different Taste from either of them: And it is yet as strange, that Salts so fugitive, and apt to dissipate in the Air, as those of Aqua fortis and Spirit of Salt, should by acquiring a New Texture put on such a degree of Fixedness, as to melt with a Metal, and that without the least perceivable Evaporation. EXPERIMENT IU. Several Phaenomena in Proof of the Doctrine of Forms and Qualities. Having made a Salt of very different Qualities from all others, and which is so nice in the Preparation, that it is as difficult to direct how it is to be made, as to make it; I shall rather choose to mention what Phaenomena it afforded me. The First Thing Observable was, That tho' the Ingredients of this Salt were Eminently Saline, yet the Salt itself was judged by a Stranger to be Sweet, tho' it had a Sweetness peculiar to itself, as every Sweet Body hath: Another Thing Considerable is, That tho' it be of an Inoffensive Smell, when cool; yet if exposed to a considerable Heat, it emitted Effluviums more strongly than those of Aqua fortis, Spirit of Armoniac Salt, or Distilled Urine; whereas those Fumes being again united, into a Salt, became Inoffensive as before. And it is further to be Observed, That tho' all Volatile, Fixed, and Lixiviate Salts are so specifically different from each other, that being mixed together, they ferment, and by that means destroy each other, and unite into a Substance different from each; yet this Salt is so powerful, as to be destroyed by none of them; but being mixed with any of them, remains quiet, and without the least Ebullition: But to be further satisfied that it was different from each of the foremention'd Salts; I tried several Experiments, by which I sound, that it would neither turn Syrup of Violets red, as Acids do, nor green, as Volatile and Fixed Salts usually do; and tho' Spirit of Armoniac, Salt, or Urine will turn a Solution of Sublimate in Water, white; and Salt of Tartar will give it an Orange Colour; yet was it not in the least altered by this: Nay, tho' this Salt was dropped into a Solution of Syrup of Violets, along with Acids and Alkalyes, yet did it not hinder their Effects: Tho' in Dissolving several Substances, this Salt exceeds both Aqua fortis, and Oil of Vitriol. And it is further Observable, That tho' by a gentle Heat, this Salt wholly Sublimes; yet when mixed with Liquors, it does not fly away, as other Volatile Salts do; and tho' it be Volatile, yet it will run per Deliquium, as soon as any Salt can do, and as present reassumes its own Form, the Superfluous Moisture being taken from it; add to this, That by a gentle Heat it may be dissolved in a Limpid Liquor. And, it is endued with a Quality yet more Admirable, for it will readily dissolve, either in Spirit of Wine, or Water, or Oils themselves: whereas some Bodies which may be dissolved in Water, cannot incorporate with Oils or Spirit of Wine, and è conversò. EXPERIMENT V. Several Changes in Bodies may be effected by the Addition, or Substraction, and new Modification of Matter. The Experiment which I am about to deliver, I presume, will be sufficient to show, That Considerable Alterations in Bodies may be effected, by the Access of some Parts, and a Recess of others, the Remaining Parts being Modified afresh. The Experiment is the following, viz. Digest for some Time one Part of Sea-Salt, with a double Proportion of Spirit of Nitre; which being distilled in a Retort, till the Caput Mortunm remains dry, the following Changes of Qualities will be observable; First, That it becomes an Aqua Regis, and would dissolve Gold, but not Silver; yet would precipitate the Latter when dissolved in Aqua Regis: Secondly, The Taste is more mild, affecting the Sensory, rather like Nitre, than common Salt: Thirdly, It becomes Fusible, like Salt-Petre; and like Nitre, dissolves in the Flame of a Candle. But Fourthly, Tho' it be a Quality of Sea-Salt to resist the Action of Fire, and of Acid Spirits to cool Inflammations; yet a Lump of this Matter cast upon Coals, flamed like Nitre; as also by an Addition of Charcoal, when melted in a Crucible, it would burn with a lasting and splendid Flame, which would again renew, upon a fresh Addition of burning Charcoal. But what I chief designed in this Experiment was to turn an Acid into an Alkaly, An Acid may be turned into an Alkaly. which was effected by consuming the more Fugitive Parth of the Salts, by repeated Deflagrations; whereupon it acquired, instead of an Acid, a Lixiviate Taste; would turn Syrup of Violets green, precipitate a Solution of Sublimate, into an Orange Colour; and as other fixed Salts, would ferment with even Spirit of Salt; which Alkalyzate Nature, could not be supposed to proceed from the Charcoal Ashes; because the whole Quantity made use of, could not yield above 2 or 3 Grains of Salt: Yet that I might be further satisfied, I dropped a sufficient Quantity of Aqua fortis upon the Lixiviate Salt, till the Mixture ceased to ferment; which upon Coagulation, shot into Saline Crystals, from the Inflammable Qualities of which it appeared, That the Nitrous Spirit was united with the Alkaly. And if it should be again suspected, that the Alkaline Parts were only the Remains of some of the Aqua fortis, which might be carried over into the Receiver: I answer, That Nitre being an Acid, it must follow that two Acids united, were turned into an Alkaly. And to prosecute this Experiment further, we distilled a Mixture of Spirit of Nitre, with a double Proportion of Spirit of Salt; yet tho' some Parts of the Nitre were carried over with the Salt, the Remaining Substance would wholly flash away, if placed upon the Coals, like common Nitre. EXPERIMENT VI. Several Phaenomena exhibited by a Mixture of Oil of Vitriol, etc. Having Distilled Oil of Vitriol with a Solution of Nitre in a Glass Body and Head placed in Sand, I drew from it a Spiritus Nitri, which before Rectification would dissolve Silver, tho' it was diluted with Water triple to the weight of the Nitrous Parts. And from the Matter left behind, and evaporated to a Dryness, I obtained a Salt, which would shoot into Crystals, neither like those of Crude nor fixed Nitre, nor those of Vitriol, but of a Figure hard to be described. As for the other Qualities of it, it was easily fusible by Heat, yet was not inflammable like Nitre, tho' quick Coals were thrown upon it in a Crucible; for it was so far from that, that when it was hot enough to kindle Sulphur, it neither flashed nor flamed itself, as Salt-Petre usually does; yet this white Substance, being kept in Fusion for a while, with a little piece of Charcoal in it, smelled very strong of Sulphur, and had a very Fiery Taste on the Tongue, as also a Colour very red. Encouraged by these Circumstances, (they being agreeable to what Glauber relates of his Salt) and since he made use of Vessels of Silver, I judged it could not be Aqua fortis that he opened the Sea-Salt with; nor common Spirit of Salt, because too weak; wherefore having put an equal weight of Oil of Vitriol, and Sea-Salt together, into a Glass Cucurbite set in Sand, I obtained, besides Phlegm, a Spirit of Salt; which mixed with Spirit of Nitre, dissolved Crude Gold; and likewise when poured upon Spirit of Urine, and fermented, till there no longer succeeded an Ebullition, after a gentle Evaporation, it shot into Crystals, like Combs and Feathers; from whence it appeared to be of a like Nature to Sal Armoniac. The Experiment sometimes also succeeded, when instead of Oil of Vitriol, I made use of Oil of Sulphur by the Bell. But to apply this Experiment to our present Purpose; we may observe, That tho' Sea-Salt be so fixed, as not to be raised without a considerable quantity of beaten Bricks, to prevent its Fusion, and a naked Fire; yet when its Parts are unlocked by an Addition of Oil of Vitriol, they may be carried over with a Moderate Fire in Sand, the Vitriol being fixed and left behind; yet in other respects considerably changed, so as to be void both of the Taste of Sea-Salt and Vitriol. And from this Experiment, what I formerly intimated, likewise appears; viz. That the Figures of Salts, by being embodied with other Substances, might be so far changed, as to shoot into Crystals of very different Shapes: For from the Caput Mortuum Dissolved, Filtrated, and leisurely Coagulated, may be obtained Crystals, much more transparent and of a different Figure from those of Sea-Salt, and from each other. But to conclude this Experiment, I have found this Preparation of Sal Mirabilis very uncertain and tiresome, by reason of the Disparities of Bodies taken to be Oil of Vitriol. EXPERIMENT. VII. The different Qualities of all Bodies are theproducts of Matter variously Modified. To show that all Metals and their different Qualities, were but the Effects of one common Mass of Matter differently Modified, as to the Shape, Size and Texture of their Parts; I took the following Method, viz. Having precipitated the Bezoardicum Minerale, by an Affusion of Spirit of Nitre, on the rectified Oil of Butter of Antimony, I drew off by Distillation as much of the Liquor as I could; sometimes cohobating it upon the Powder of the Antimony; which being done, I melted pure Gold with Three or Four times its weight of Copper, which being put into Aqua fortis, the Copper was dissolved, and the Gold subsided in the form of a Powder, which was further purified by an Ancient Chemist, and by a competent heat restored to it's Natural Colour; which being dissolved in a large Quantity of the above mentioned Liquor there remained a considerable Quantity of white Powder, which would neither be dissolved by the above named Menstruum, nor Aqua Regis. The Gold being a second time reduced to a Body, by a repeated Solution in the aforesaid Menstruum, yielded more of that Powder, which reduced to a Body was White, and being dissolved in Aqua Fortis had the same nauseous bitter Taste with Silver; so that it is plain the Transmutation of Metals is not impossible, nor Gold a Metal impossible to be destroyed; so that I am more apt to believe, that by proper Menstruums the Body of Gold may be so ordered, as to communicate a Tincture to a Liquor duly conjoined; The Transmution of Metals not impossible. as when Sulphur and Mercury by a Coalition constitute Vermilion; since from this Instance it is plain, that the Colour of the Tincture (as well as of the Vermilion) may be produced by the Position and Texture of some Particles of Gold associated with that Liquor. And that the Colour of such Tinctures as well as of the Gold itself depend on certain Particles conveniently Modified, I rather believe, because I am told, that a known Man in the Netherlands had a certain Menstruum, which would extract a blue Tincture from the Calx of Copper, prepared by a Dissolution in Aqua Fortis, leaving a white Powder behind, which would by Fusion be turned into a Metal of the same Colour. A second Inference which may be drawn from the foregoing Experiment, is, that if Gold, one of the most Permanent Bodies, may have its Texture destroyed, there is no Body in Nature but may undergo a Change, when wrought on by an appropriated Agent; and that the noblest of Metals may be Mechanically transmuted; from whence it appears also, that the noblest of Forms, are but the Results of the Texture of the Parts of Matter of which they consist; and a Convention of Accidents, which are the Substratum of that Texture: So that without a substantial Form, merely by a saline Menstruum, the Body of Gold may be changed into another substance, of very differing Qualities from what it had before. But to render our present Experiment more instructive; I shall add another Attempt, to sublime Gold after the following Method. Having then dissolved laminated Gold in some of the above mentioned Menstruum, we drew it off in a Retort placed in a Sand-Furnace, by which means a considerable Quantity of Gold was elevated, and either fell into the Receiver in the Form of a Golden coloured Liquor, or shot into red Crystals like Rubies in the Neck of the Retort; which in the Air would run per Deliquium: Where we are to observe, that by a new Affusion of the Menstruum upon the remaining Calx, more of itwould still be elevated by Distillation. But to make this Experiment more serviceable, it will be necessary to Note, that upon pouring running Mercury into this elevated Tincture, the Particles of it were immediately Guilded, and by degrees, the Mercury being kept in Motion, the whole Liquor lost its Tincture, which being decanted, and the Guilded Mercury with a good Quantity of Borax Melted in a Crucible, the elevated Gold was reduced into a Mass; which evinces what I just now taught, viz. that a Liquor might be Tinctured by having the Parts of that Body, from whence it received its Tincture, conveniently interwoven in its Texture, without being wholly destroyed. And here I think it seasonable to advertise, that having elsewhere mentioned a Volatile Gold in some Oars, where none of that Metal is to be found; I would be understood to mean it Volatile in no other Sense, than the foregoing Sublimation intimates, viz. that its Volatility depends on a mixture of Volatile Parts which carry it along with them, when dissolved into very minute Parts; so as to be capable of Swimming in that Vehicle. EXPERIMENT. VIII. How so hard a Body as Silver, etc. may become a sour substance by an alteration of Texture. Having dissolved an Ounce of refined Silver in Aqua Fortis, and permitted it to crystallize, we found, that the Silver, by the addition of Acid Salts, was increased in weight several Drachms; which distilled in a Retort, with such a degree of heat as made the Retort red hot, yielded a Phlegm eminently Sour. Which shows, that a very Bitter Body may yield a substance of a quite different Taste. For the Liquor being cold in the Receiver, Smoked as well as Smelled and Tasted like Aqua Fortis, and by corroding Copper turned it into a Blevish Colour. After wards we made a Solution of Minium in Aqua Fortis, and having by Filtration and Evaporation procured a Saccharum Saturni, we Distilled it in a well coated Retort, over a naked Fire, and obtained an offensive Acid which had the Smell of Aqua Fortis; which being put upon Minium, bubbled, and making a considerable noise, presently afforded a Liquor, from which might easily be obtained a true Sugar of Lead: Where it is observable, that the Caput mortuum, was neither Sweet, as before Distillation; nor Sower, as the Body drawn from it; but insipid and easily reducible, by Fusion, into a malleable Lead. Phaenomena to be observed in this Experiment. In which Experiments, the following Phaenomena are also Remarkable: First, that the Salt, which increased the Silver in weight no more than a third or fourth Part, was able to Sublime the greatest Part of that fixed Body. Secondly, that the Parts of the same Liquor, being mixed with three several Metals, may produce as many different Tastes; tho' the same Aqua Fortis should be successively made use of in those three Experiments, and howsoever varied in respect of Order in the Trial: And here we are to observe likewise, that Part of the Distilled Spirit of Nitre, being poured on the Caput Mortuum of Saccharum Saturni, turned some Parts of it into a Vitriol; and another Part of it being poured upon Filings of Silver, the Silver, being partly dissolved with a hissing Noise, was Coagulated into a Bitter Salt. EXPERIMENT IX. Because Transmutation of Bodies, whose Textures are esteemed Primordial, as those of the Elements, and which are found to be Ingredients of most Compositions here below, will be a further Confirmation of the Possibility of Altering the Textures of other Bodies; I shall subjoin, what Progress I have made, in order to turn Water into Earth. A Transformation of Water into Earth. Having therefore in a Glass Vessel distilled Fair Rain-Water, and several times re-distilled it again; we found, that after every Distillation, there was a considerable Quantity of white Earth remaining at the bottom of the Vessel, which was more plentifully afforded in the latter Distillations, than the first; and therefore we had the greater Reason to believe, it could be nothing else but a certain quantity of Water, turned into Earth; which afforded the following Phanomena, viz. 1. Being put into a Microscope in the Sunbeams, Phaenomena exhibited. it appeared to consist of Parts exceeding fine, which were as fine in the Microscope, as Hair-powder usually is to the Eye; yet not in the least Transparent. 2. Being mixed with Water, it turned it into a whitish Colour, as the Powder of white Marble usually does; yet being settled in the Bottom, it remained undissolved. 3. After it had lain a considerable time in a Red-hot Crucible, it was neither diminished in quantity, nor did it in the least smoke. 4. It exceeded Water in weight, so as to be equal to twice its Bulk of Common Water, being almost as heavy as Wood-ashes, freed from their Salts; which, to its Bulk of Water, is as 1 to 2 ⅙, which does not much come short of the weight of white Glass, which is twice and a half heavier than its weight of Water: So that from these Phaenomena, we had Reason to term the Forementioned white Substance, Earth; considering likewise its fixedness, and other Qualities. But further it is to be Observed, That the Glass in which it was distilled, was not in the least damaged by this Process: as also, That an Ounce of Water yielded six Drachms of Powder, Water almost wholly convertible into Earth. a considerable quantity of Water still remaining behind. So that this Experiment is no small Confirmation of our Hypothesis: For if Elements themselves may be Transmuted, and Artificially Destroyed, by an Alteration of the Texture of their Parts; why may not Considerable Changes be effected also in other Bodies, by a Local Motion, and a New Manner and Form of Union of Parts, of different Figures and Sizes; since in this Experiment, the Parts of Water being modified anew, form a Solid Body, of very different Qualities from what belonged to it before, as want of Transparency, Solidity, etc. How Water acquires the Form of a Solid Powder. As for the Manner of its being so modified anew, it may easily be conceived, That the Parts of Water, being put into Motion, and rubbing upon one another, by violent Occursions, might be so altered and adapted as to stick together, and to form several little Moleculae, which being more condensed, and consequently heavier than Water, could no longer swim in it; but obtained the several New Qualities before mentioned. And that the Change was thus effected, we have Reason to believe; since by a bare Circulation, in a just Degree of Heat, Quicksilver will assume the Form of a Powder, which will not with so much ease be raised by the Fire, as the Mercury itself; but this will be further illustrated by the Tenth Experiment. Inferences drawn against the Doctrine of the Chemists. Therefore to draw Inferences from this Experiment, which may disfavour the Hypostatical Principles of the Chemists; If Water be capable of being changed into Earth, by the same Reason the other Ingredients of Bodies may; and in the Analization of Bodies there may be a Transmutation of Substances, as well as a Separation of Pre-existent Principles. From hence also may be brought strong Arguments against Helmont; who, because he boasted of an Alkahest, which, he says, would turn all Bodies into a Liquor, therefore concluded all Bodies were made of Water; for by the same Reason I might say, All Bodies are made of Earth; because Water may be turned into Earth: So that tho' he should turn all Bodies into Water, yet that Water being again capable of being disguised, it would only show, That Water and Earth may be mutually Transmuted, by a successive Change of Texture. But to leave these Reflections, I shall mention some Scruples, concerning this Transmuted Powder, which I could not have time to satisfy myself in: As, Whether the Water Remaining was lighter than before Distillation? Whether the Particles of Insipid Bodies, may act as Menstruums in the Dissolution of others? not but that they may be so changed in the Vessels of Plants, as to become sharp and powerfully penetrating. Whether the Weight of the Glass-Vessel, was diminished by this Experiment? I should likewise be willing to be satisfied, Whether Water itself be truly a Homogeneous Body? which if it be, it will be strange, that without the help of a Plastic Power, or Seminal Principle, it should be so transmuted; since that a bare Convention of the Particles of a Fluid into a Concrete should alter their Specific Gravity, is hard (if not impossible) to be paralleled by Art. But in this Experiment it is further Remarkable, That Oil of Vitriol poured upon this Powder, would corrode it, and that by an Effusion of Spirit of Salt there was raised a considerable Ferment; as when Spirit of Salt is put upon Lapis Stellaris: So that I suspected the Rain-water might be impregnated with some of the Sandy Parts of Glass dissolved, by the help of the Fire, and actuating the Particles of it; but this Suspicion was partly taken off, because I had observed the like Ebullition, upon a Mixture of Spirit of Salt with Wood-ashes, which were cleared of their Salts in Boiling Water. But to conclude this Experiment, we may further reflect upon the foregoing Suspicions; that if the Body of the Glass-Vessel were in the least dissolved in this Operation, it will be a powerful Instance of the Force of Insipid Menstruums; and it will be no less a Confirmation of the Doctrine of Forms and Qualities before delivered, that Water itself is subject to undergo such considerable Changes, as this Experiment shows it is. I might produce a great deal more on this Occasion, to corroborate what I have delivered concerning Transmutations; but I shall only add, that I, as well as two several Persons whom I employed, have without the Addition of any thing, obtained from Spirit of Wine, which was wholly inflammable, a considerable Quantity of Phlegm; and that too, without its being affected by any Visible Body. EXPERIMENT X. Consider able Changes may be wrought in Bodies by Mixture, and the Texture thence resulting. To conclude this Chapter, I shall add an Experiment, to show what sudden Productions and Alterations of Qualities may be effected by a Coalition of the smallest number of Ingredients, generally taken for Homogeneous Bodies; from whence it will appear, That the Changes of Bodies, in themselves considerable, may be effected by very easy Mixtures, viz. Having by Degrees mixed an equal weight of Spirit of Wine, and Oil of Vitriol together, and placed them in a Bolt-head, stopped close with hard Wax, and a Cork; digest the Mixture in a Moderate Heat, for some time; then pour it out into a Glass Cucurbit, luting on a Head and a Receiver, to preserve the Subtle Spirits from flying away; then with a moderate Heat draw off the Spirit of Wine, till the Drops begin to come over-sowrish; then shift the Receiver, and carefully go on with the Distillation, increasing the Fire till as much is drawn off as you can, keeping the Substance remaining in the Cucurbit, in a Glass well stopped, and secure from the Air. The Phaenomena exhibited by this Experiment were the following: First, That the Spirit, first drawn from these two Inodorous Bodies, was endowed with a Smell different from all others, and parts tho' pleasant and fragrant, yet very subtle and penetrating. Secondly, That the Liquor, drawn off last, had a very strong Sulphureous Smell, which stunk, and affected the Sensory, so powerfully, that it would almost take away one's Breath. Thirdly, This Mixture yielded a Liquor, which would mix with neither of the former; yet was very subtle, pleasant, and Aromatical. Fourthly, The Substance remaining in the Bottom of the Vessel, was Opacous, and almost as black as Jet, and withal very brittle. Fifthly, And tho' it was made up of two Liquors, the one corrosive, and the other inflammable, and both of very pungent Tastes; yet was it void of Taste, and could not without great difficulty, if at all, be brought to burn. Sixthly, Neither would it be mixed for some Days with Water, tho' the Oil and Spirit, readily diffuse themselves in that Liquor; besides, it was of so very fixed a Nature that it would not be raised by a strong and lasting Fire, tho' both Oil and Vitriol, and Spirit of Wine be extremely Volatile. And now, Having thus in short laid down these Experiments, as sufficient Proof of the Doctrine before delivered, I shall conclude with this Reflection, viz. That in all the Changes and Alterations, that have been effected by Art, it appears, that they are so far from depending on the Imaginary Substantial Forms of the Schools, that they evidently appear to be the sole Effects of Local Motion, so altering the Figures and Sizes of the Minute parts of Bodies, or otherwise transposing them; as, upon a fresh Association and Coalition of them, to form New Concretes, of Textures very different from the former. And if Motion, Bulk, and Shape, together with peculiar Textures, be enough to cause so many different Phaenomena, as have been laid down; there is no Reason, why other Qualities may not be produced by the same Fertile Principles; since all the Difference betwixt the Works of Nature and Art, in altering the Forms of Natural Bodies, lies in this, viz. That in the Works of Nature Active and Passive Bodies casually meet together; and in the Latter the different Substances, concerned in every New Production, are brought together by an Artist; for in both the Agent acts as a Natural Agent. CHAP. X. An Experiment, with some Considerations touching the differing Parts and Redintegration of Salt-Petre. SALT-PETRE is a Concrete so universally concerned in the Composition of most Bodies, that it will be of no small Import to Natural Philosophy, to inquire throughly into the Nature of it; which will in some Measure appear, by considering how many Substances may be drawn from it, or turned into it; which will be briefly intimated in the following Experiment. An Attempt to redintegrate the Form of Salt-Petre. Having, according to the usual Method, Crystalized Nitre, we melted four Ounces of it in a Crucible into a Limpid Liquor, throwing in Live-Coals successively, till it would kindle and fulminate no longer; and continuing it in a strong Fire a considerable time, to dissipate the remaining Volatile Parts, and then breaking the Crucible, we divided the fixed Nitre immediately into two Portions; one of which being dissolved in as much Water as was sufficient, we dropped in Spirit of Salt-Petre, till the Ebullition, raised by the Mixture of these Liquors, wholly ceased; and then filtrating the mixed Liquor, we exposed it to the Air in an open Glass-Viol; and on the other Part undissolved, we likewise dropped the same Spirit, till the Firmentation ceased, exposing it to the Air in an open Glass-Jar. In the former Mixture, wherein the Water was put, in a few Hours certain Crystals of Salt-Petre stuck to the Lower Parts of the Glass, amongst which were several other Crystals, like Mustardseed, encompassed with a downy Substance. The Crystals the next Day being considerably greater, were taken out, and both by their Burning and Shape, appeared to be Nitrous, (Nitrous Salts being furnished with flat Sides, which when opposite are usualy parallel;) and as for that downy Matter which adhered to some of them, we judged it to proceed from the Disproportion of the Volatile and Fixed Parts of the Nitre, which were to be joined together anew. These things being observed, we poured the remaining Liquor into an open Glass-Vessel, which in about three Weaks-time, being again Saturated with Petre, we poured it from the Salt, and evaporated it in a Digesting Furnace. The other Mixture, which was only fixed Nitre and Spirit of Salt-Petre, for the most part presently Subsided in the Form of a Salt, which when dried in the Air, was of very irregular Figures; and, in some Parts, not much different in Shape from Salt-Petre; which it also much resembled in Burning, tho' the Deflagration was in some measure peculiar to itself. But this Salt, together with the Liquor swimming upon it, being preserved in the Air for about a Month longer, after Evaportion, the one half shot into Crystals, which burned much like Petre, and had a Similar Figure, tho' a different Taste; and the other half, being speedily exhaled, shot into Crystals, of a distinct Figure from all others. Cautions to be observed in the Foregoing Experiment. Now to make this Experiment clearer, the following Things are to be observed; 1. That in Fixing the Nitre, New-Coals are not to be cast into the Crucible, till the former are almost spent, or be thrown out by the violent Exhalations of Nitrous and Volatile Parts. 2. That the Quantity of Spirit of Nitre dropp' upon the Fixed Nitre, was almost proportionable to the Salt-Petre, spent in the Fixing of it. 3. That this Fixed Nitre was very little different in Taste from Salt of Tartar; had the same aptness to Absorb Air, and to relaxate in moist Air: Yet it differed in Colour, being betwixt a Blue and a Green One, which it lost upon the Affusion of Spirit of Nitre. Another Method of Reuniting the Parts of Salt-Petre. But this Method being tedious, I shall propose a Way more expeditions, which is this; Having run Fixed Nitre per deliquium, and by Filtration separated it from its Faces, we dropped upon the Liquor Spirit of Nitre, which, after a Ferment usual to a Mixture of those Liquors, presently shot into Crystals, in Shape, as well as Nature, manifestly Nitrous. A Third Method. Another way we took was this: Having Impregnated a Solution of Fixed Nitre in Water, with Spirit of Nitre, and filtrated it through Cap-Paper, the Cool Liquor, in a short time, shot into Crystals, like those of Petre; and the Liquor, being again Evaporated, afforded a fresh Quantity of Crystals not unlike the former. But lest the Sal-Petre re-produced by the Coalition of these two Bodies, should be thought to lodge in the Fixed Nitre; and only to be unyoked by their Solution, it is requisite to annex, That the greatest Quantity that can be supposed to remain in the Fixed Nitre, would not amount to such a Quantity as that Mixture affords: And to make the Matter less suspicious, we impregnated a Solution of Pot-Ashes, after the same manner as we had done the Fixed Nitre, Salt-Petre obtained from Pot-Ashes, Aqua fortis, and Salt of Tartar. which after Filtration and Evaparation, shot into Crystals, which 0103 0207 V 3 were very like Salt-Petre in Taste, as well as their Deflagration upon Live-coals. We likewise obtained a small Quantity of Salt-Petre, from Aqua fortis and Salt of Tartar associated. But to draw Inferences from the Foregoing Experiment; from hence we may learn, That the Sensible Qualities of Bodies may be accounted for by the Mechanical Motion, together with the Figure and Disposition, or Modification of their Parts. And first, tho' Salt-Petre be a Body inwardly, and in itself cooling; yet the Parts of it differently Modified, in our Experiment, being put together, do immediately put each other into so violent a Heat, that I could with much ado hold the Glass in my Hand; so that Heat seems to be nothing but a quick Motion of the finest Particles of Bodies, since it no longer continued in that Mixture, than the Parts of it were in Agitation. Upon the Mixture of these two, viz. the Spirit of Nitre, with the Fixed, there was likewise produced an audible Sound, proceeding from the Percussion of the Air, by the swiftly and impetuously agitated Parts of the Mixture: A Sound like to which is produced by a hot Coal cast into Water, or into melted Nitre in a Crucible, tho' the Latter causes a Sound much louder. Which Sound probably proceeded from the Percussion of the Air, because the Motion of a Bullet, or a Stick, where the Quickness of the Percussion puts the Air into an Undulating Motion, will cause a Sound, as soon as that Undulating Motion reaches the Ear; and it is further confirmed, because that Sound no longer continues, than the Parts are violently agitated: And here it is to be observed, That the Sound, produced by the Mutual Conflict, ceases long before the Heat, which is acquired by that Ebullition; from whence it may be inferred, that the same Intestine Motion of Parts which are able to produce Heat, are incapable of causing Sounds; as Amber continues warm a considerable time after the Sound, made in rubbing of it, ceaseth. Several Qualities flow from an Alteration of Texture. We observed likewise, That the Fixed Petre was of a Colour betwixt Blue and Green, which it presently lost upon the Mixture of the Acid Spirit, the Disposition of Parts being so altered, as to reflect the Rays of Light differently to the Eye; A Change not unlike which happens upon the Exposing Fixed Nitre to the Air: And it is not less to be admired, That Soot, which is Black, and a Congeries of Opacous Exhalations, should, by the help of a good Fire, fill the Receiver with Fumes as white as Milk: And the Colours to be observed upon the Sublimation of Black Antimony, and White Salarmoniack are no less pleasant. But to return to the Experiment: Having not long ago attempted to make Salt-Petre, of Salt of Tartar, and Aqua fortis, the Mixture united, proved to be of a very Green Colour, which resided more peculiarly in some Parts of it than others, tho' the Salt of Tartar was a particular Preparation, whose Crystals were as white as Sugar Candy. It is on this occasion likewise further to be observed, That tho' Fumes of Nitre, raised Distillation, be of a Red Colour; yet they condense into a Liquor altogether void of it; and also, That Fixed Nitre, tho' an Opacous Body, yet does it unite, with the imbibed Spirit, into Diaphanous Crystals. Several Qualities destroyed. and regained by the Redintegration of Salt-Petre. There is likewise to be observed, Upon the Mixture of these two Ingredients, a very offensive Smell, caused by the Spirit of Salt-Petre, emitting stinking Exhalations, stirred up by the Mutual Conflict betwixt it, and its Fixed Salt; where it is strange, that this Mixture should have a Smell, which is neither in Nitre, nor either of the Ingredients; and yet, that it should lose that Smell again, when turned into Nitre. Besides the Taste of the Spirit, being strongly Acid, and the Taste of Nitre, like that of Salt of Tartar; it is surpizing, that these two should unite into a Body of so much less pungency in Taste as Nitre, bating that it is a little sharper by reason of some Spirituous Parts sticking to the Particles of the Nitre. But besides these there are several other Reflections may be made on the preceding Experiment; for it seems a Question, whether there is any real necessity of a distinct Sulphur to render a Body Inflammable, or whether rather Inflammability depends on a disposition of Matter to be put into Motion by the help of adventitious Bodies; as when the Ingredients of our Experiment are mixed; or when a Piece of Iron is cast into Spirit of Nitre; for the Parts of that Liquor, which before were quiet and cold, meeting with Pores which disorder their Motion, they presently begin to move among one another with a strange Rapidity, and to cause such a Heat, that the Vessel would burn the Hands of them that held it: And here it may not be amiss to take notice of one thing further, that Occurs in our Experiment, viz. that tho' Nitre put upon a burning Coal, or a burning Coal being cast into it, will consume itself, in a Blue Flame, yet when it is contiguous to the Sides of the Crucible which is red Hot, it melts without the least Flame. It may be also worth Enquiry, why Nitre which is a solid Body should not rather stick in the Form of Sublimate to the Receiver, like Sal Armoniac, than condense only into a Liquor, which does not again coagulate as some Volatile Spirits do. But leaving these Phaenomena, I shall observe further, that though Spirit of Nitre, exposed to the Air Insensibly exhales, yet when associated with its own fixed Salt, it admits no such Effluviums. Another thing to be observed is, that upon a Mixture of these two Liquors, several Saline Parts are tossed out of the Glass into the Air, which falling down again, several Grains of Salt will remain on the outside of the Vial, which will be visible if the Experiment be tried in the Sun Beams. And that there is a very brisk Motion amongst the Parts of Spirit of Nitre, is evident by dropping some of it into a solution of Salt of Tartar; for immediately some Grains were shattered in Pieces, and thrown up to the top with a seeming Violence; till the strength of those Liquors was mutually diminished by their frequent Occursions: And that the Parts of each have contrary tendencies in their Motions is plain, from this, viz. if when the Ferment ceases, more of one of these Liquors was dropped in, there followed no Ebullition, till some of the other was added to Ferment with it. The same Particles of Matter have different Effects when in a Fluid, from what they have in a solid Form. And here it is seasonable to observe what different Effects the Parts of these Bodies have when at liberty and disjoined in Liquids', from what they produce when locked up in Concretes, tho' their Effects, even then, are not wholly to be attributed to the briskness of their Motion, but also, to their determinate Sizes; by which means Aqua Fortis, which leaves Gold untouched, will dissolve Silver; yet, by an Addition of Sal Armoniac, it having acquired a new Figure, and a peculiar Motion, it Works upon Gold; and for the like Reasons a Solution of fixed Nitre will dissolve Unctuous Bodies, which the Acid Spirit will not Work upon. Again we may observe, that the several substances into which Salt-Petre is reduced, viz. the fixed Salt and the Volatile Liquor, are both different from the Concrete itself; which is an Argument against those Chemists that pretend, that Bodies Distilled, retain the Virtues of those Bodies they are Distilled from; Chemistry rather destroys than discovers the Principles of Bodies. for the Acid Spirit of Nitre will precipitate the same Bodies, which fixed Nitre dissolves. And so Spirit of Nitre will turn a Tincture of Brasil into a Yellow Colour, which it will lose, and in some Measure by an addition of a Tincture of fixed Nitre, regain the former, whereas a Solution of Salt-Petre changes neither of these Tinctures. Eut to proceed, This Experiment gives us Reason to believe, that the Air is considerably concerned in the Production of Salt-Petre, and in giving a Figure to its Salts; since the Crystals, which shoot in the Solution exposed to the open Air, are of a more exact Size and Figure, than those obtained after a quicker Evaporation. Besides which we have observed, that a Mixture of Aqua Fortis and Salt of Tartar yielded Crystals much more like Nitre, when it had been exposed to the the Air for some time, than what it afforded upon an immediate Crystallization. As for the Reason why the Crystals which shoot in the Air, are more naturally Figured than others; I conceive it to be, because the Air is a more quiet and undisturbed Vehicle for them to move leisurely in, by which means they have the Liberty of uniting as they ought, to form Crystals of a natural Figure, which Guess is confirmed, because the Crystals which shot in Water, where they have room enough, and an indifferent Vehicle, were more perfect than those, which were produced by a Mixture of the nitrous Powder and Saline Spirit, where they were forced, for want of Room, to Cry stalize, before they had time to Convene after a manner requisite to make them of a natural Figure and Size. But to proceed: This Experiment, which shows how a Body divided into different substances, by Distillation, may be again united into an Original Concrete, will be a very strong and convincing Instance to prove, that the Forms and Qualities of Bodies depend on an essential Modification of their Parts; and that the difference observable in particular Substances, depends on a different Texture, and a Coalition of Parts of different Figures and Sizes; so that the Redintegration of Bodies is no more, but a restoring of their former Parts into the same Order and Position, being Artificially handled, so as to acquire their former Sizes and Figures in order to their Coalition. Yet this I think necessary to be represented, viz. that the Composition of Nitre is so little Organical, that it will be hard to judge what success, in order to Redintegration, may be expected in other Bodies, where the Fabrics of them are so curious, by Reason of their numerous Ingredients, and the curious Contexture of them, that the latter is not to be imitated by Art, in the Production of Substances much less Organical, than the Parts of living Animals. Chemical Medicines laid aside too rashly. The last Observation I shall make on our Experiment, is, That from what hath been said it may be thought that some Chemical Medicines may be too Rashly laid aside by some Physicians, who suppose, that the Menstruums made use of in their Preparations, are in some measure mixed with them; since, besides that those Salts may by care be washed away, several Parts of them may be so altered by Corrosion, that those, associating with other Particles of the Body they work upon, may degenerate into an innocent Concrete: An Instance of which we have in our Experiment, where a corrosive Spirit and a Caustick fixed Salt, unite into an innocent Medicine. And that Corrosive Salts may in a great measure be dulcified by their acting on other substances, is evident in a Mixture of Spirit of Vitriol and Crabs Eyes, or any other testaceous Body. And again, though Vinegar powerfully corrodes calcined Lead, yet uniting with it, it constitutes a Sweet Body, in which the sharpness of Vinegar is perfectly destroyed. And tho' it be an Argument usually alleged against the use of Medicines so prepared, that from several of them corrosive Particles may be drawn; yet since the same may be Effected by the Action of Fire upon Salt-Petre, the Objection is as invalid as the general Practice of Physicians can make it. CHAP. XI. Containing the History of Fluidity. WHETHER Fluidity and Firmness, might not with more Reason be esteemed States than Qualities of Bodies, or not; this is most certain, that they are to be accounted the most General Affections of Matter, all Bodies being either Fluid or Solid: If then these Qualities or States of Bodies be so General, it will be of moment to consider the Causes of them; and the rather in this place, because the Foregoing Experiments of Salt-Petre may serve to illustrate them. The Definition of a Fluid Body. To proceed then: A Body is said to be Fluid, because it consists of Parts, which easily slip upon one another's Surfaces to and fro, when moved, by Reason of the Porous Interstices, which remain betwixt those Parts, which they are made up of, they not being wholly Contiguous on every side; and also, because by Virtue of that Motion, they spread and diffuse themselves on every side, till opposed by some Solid Body, to the Internal Superficies of which, they presently adapt themselves. And what Thoughts Epicurus, and the Ancient Corpuscularians had of Fluidity, will appear from these Verses of his Paraphrast Lucretius. Illa autem debent ex Laevis at que Rotundis Esse magis, fluido quae Corpore liquida constant. Nec retinentur enim inter se glomeramina quaeque, Et procursus item in proclive Volubilis extat. And indeed, we may rationally believe, That the Smoothness of their Parts may much contribute to the Fluidity of Liquors, as well as the Globular Figures of them; tho' there are several Fluid Bodies, whose Parts are of Figures very various, besides Flame and Air; the Figures of whose Parts are very irregular. * Bodies whose Parts are less condensed than Water, to be esteemed Fluid. And here we are to take Notice, That to render a Body Fluid, there is no need that its Parts should be so closely condensed, as those of Water are; since Flame and Smoke may be so managed, as to resemble Liquid Bodies; of the Latter of which we have Proof, by blowing Rosemary-Smoke into a Glass-pipe, which, if when it is filled, the lower End be stopped, and the Pipe be held in a Perpendicular Line, the Surface of the Fumes will subside till Level; and tho' the Pipe be inclined several ways, yet the Superficies of the Smoke answers to the Horizon, till the Glass be further inclined; and then, the Smoke will run along the Pipe like Water, dispersing itself afterwards in the Air. But to return to the Cause of Fluidity: We conceive that there are Three things requisite to render Bodies Fluid: Minuteness of Parts requisute to Fluidity. 1. The Minuteness of the Particles which constitute them; by which they are disposed to an Intestine Motion, and to be preserved in it more easily; as the Parts of Lead, Quicksilver, and Gold, when dissolved by a Menstruum, are easily raised and mixed with the Parts of that Menstruum. Nay, Fluidity so much depends on the Minuteness of the Parts of Matter, which constitutes Fluid Bodies, that the Parts of Antimony, dissolved and broken into small Corpuscles, may be turned into Butter of Antimony; and, that Butter of Antimony, is chief made up of the Substance of the Antimony, is evident, since by a Mixutre of fair Water, a white Calx will precipitate, easily convertible into Glass of Antimony. And Nature herself supplies us with further Instances; since the very Substance of Bones, is, by Comminution in the Stomaches of Dogs, turned into a Liquor: And to confirm this Observation, I shall add, That I knew a certain Gentleman, who was a close Student, who lived for several Days together without the least Drink, tho' in the mean time he sweat moderately, and easily enough, his Urine being agreeable to his Constitution, as the Urine of other Men's generally is to theirs: But that Solid Substances may yield, and be turned into Fluids', by a Comminution of their Parts, may be evinced by the Fusibility of Metals; since the more the Massy Particles of Metal are broke into small Parts, the more their Fluidity is increased. A Fluid may be obtained from a Consistent Body. And here it may not be unseasonable to inquire, how it comes to pass, That a Transparent Liquor should be drawn from such Brittle Bodies as Common Salt; I know it is usually alleged, That the Fire only separates the Moist, from the Dry Parts; but since Bodies already Calcined or Melted, must needs by the Action of the Fire, have their moist Parts likewise so separated; it is rather probable, That the Fire only divides their Parts, and puts them into a violent Agitation, by which they are raised in the Form of Vapours, which falling into the Receiver, condense into a Fluid; whose Parts, by reason of their Shape and Size, being apt for Motion, continue to move up and down, and so preserve that Body in the Form of a Fluid, the Motion of the Air, or of some Interposed Bodies concurring to preserve the Parts of that in Motion likewise; and that the Air abounds with Parts, perpetually in a various Motion will appear by and by. Some Bodies more easily preserved fluid than others. But in the mean time that a much greater Degree of Motion is requisite to preserve some Bodies in a Fluid Form than others, is plain, since several Bodies will be froze with one Degree of Cold, with which others will not; and tho' the Watery Parts of Wine, in some Countries, will freeze; yet the Spirituous Corpuscles of the same Liquor remain untouched: And tho' it is evident, by the help of good Weather-Glasses, that Cold condenses the Air; yet it was never so far condensed, as to become Ice; because the perpetual Motion concurring with the Minuteness and Shape of its Parts, they are always in an Agitation requisite to keep it in that Form; and it is not improbable, but that the Parts of Salt are very Minute; since, from Experiments before mentioned, it appears, That Spirit of Salt and Urine, will unite into a Salarmoniack; and it is further confirmed, since, Common-Salt, mixed with Aqua fortis, will dissolve Gold, as well as Spirit of Salt joined with the Latter: and tho' Crude Nitre itself, be mixed with Spirit of Salt, the Resulting Mixture will supply the Place of an Aqua Regis. And I am informed that, that a Chemist in Holland, drew no less than fourteen Ounces of Spirit from a Pound of Salt, a whitish Clay being made use of instead of the Common Caput Mortuum; and that when he had dephlegmed the Spirit, twelve Ounces remained very highly rectified; which may be something in favour of Beguinus, who pretends to have got a Pound of Spirit from a pound of Salt. But it may be a Question, Whether the Fluidity of these Bodies may not in part proceed from the Action of the Fire, working upon some Parts of the Concrete; since a Phlegm or Water may be obtained from rectified Spirit, so as to change Part of it into a moist Body like Water. And this will rather be thought probable, if we consider and believe what the Famous Helmont says, viz. That he could reduce Oil and Salt into Insipid Water, The Figures of the Parts of Bodies, as well as their Sizes, contribute to tseir Fluidity. without the help of that Noble Alkahest, which would render Gross Bodies wholly Liquid. And here it is requisite to add, That it is not only the Sizes of the Parts of Bodies, that endues them with a Disposition to Fluidity, but also, their Shapes; and I am the more confirmed in this Opinion, because, having distilled Oil of Olives in a Glass-Retort, per se, near a third Part of it was coagulated in the Receiver, into a whitish Substance, not very much unlike Butter; where the distilled Substance, which usually is fluid, tho' drawn from solid Concretes, was on the contrary in this Experiment, a Consistent one, yielded by a Liquid; for which no other Reason can be given, but that the Shape of the Liquid Parts were so altered, as to become unfit for Motion. But to return to the Reason of Fluidity, it is evident, That in pouring of Sand, Corn, Flower, Apples, Walnuts, etc. out of a Sack, that that Aggregate of Bodies, whose Parts are the least, appears most like Liquids; and it is commonly observed, That Whites of Eggs, by being beaten with a Whisk, presently lose their Clamminess and Viscidity, and are reduced to a thin and fluid Substance, their Parts being broke asunder, and more minutely divided. And I have observed, that That Jelly (which is by the Vulgar thought to fall from a Star) by being a long time digested in a well-stopped Glass, became a permanent Liquor. Again, it is observed, That when Silver is to be cast in Moulds, and to receive the Curious and Fine Impressions of Hair-Lines, the Metal is not only to be poured in very hot, but to be kept a Considerable Time in Fusion, before it is thin enough to run into those Lines, and to take exact Impressions of them; from whence it appears, That Bodies already fluid, may become more fluid; and the like Instances might be brought from other Bodies, as Turpentine, Oil, etc. And if what Helinont asserts of the Liquor Alkahest, be true, viz. That it will turn all Substances, whether Minerals, Metals, Plants, or Animals, into a fluid Substance, of an equal Weight with each other; than it follows, That to divide a Body into Parts small enough, is enough to make it fluid. And to this I must add, that considerable Changes may be effected, merely by a long Digestion in Vessels well stopped, and placed in a Convenient Heat. 2. The Second Requisite to constitute a Fluid Body, is, That it should have considerable Vacuities or Pores, betwixt the Parts of it; Porousness in Bodies requisite to their Fluidity. for if there were no such Spaces, the Parts being put into Motion, would not have Space to continue it in, nor could one Particle by the Impulse of another, be forced to give way. But before I proceed, it will be requisite here to Note, That by Spaces, I would not be thought to mean Vacuities properly so called; but that there is no such Substance betwixt them, which will obstruct the Motions of the more Solid Parts. This Caution being premised, I shall (to illustrate this Second Requisite) observe, That Snow, which is of an open and slight Texture, before it is compressed, may soon be squeezed into so close and compact a Lump, as to resist a very strong Pressure; the Air, which before was interposed betwixt the Parts of it, being pressed out. Again, we may observe, That when Water is closed up in a Bladder, and wants its Liberty to move in a yielding and free Medium, the Parts thus confined together, resist Impressions like a Solid Body; and this Experiment I the rather made use of, than a Bladder distended with Air, because the Distension of that, might partly be attributed to the Spring of the Included Air. How such Vacuities contribute of Fluidity. But it is further to be observed, That tho' such Vacuities are necessary to constitute Fluid Bodies, yet they are only so, to use School-Term, as Removens, prohibens, i. e. they prevent the Inconveniencies which must be the Consequence of a Plenitude, viz. Want of Liberty to move; or in other Words, as they dispose the Parts of a Body, to yield to each other's Motion. And here I would Note, That tho' in most Liquid Bodies, this Doctrine may take place; yet I conceive it not altogether absurd, to Question, Whether Matter may not be so tightly agitated and divided, as to fill up these Vacuities, and to be squeezed into any Figure, as Occasion requires. But not to spend Time in examining this Point at the present, I shall proceed A Perpetual Motion if Parts requisite to Fluidity. 3. To the Principal and last Requisite, in Modifying a Fluid Body; which is, That all the Particles of a Fluid Body, should be separately and variously moved up and down, either by Virtue of some subtle Matter diffused through their Substance, or an inherent Quality of their own. For the Difference betwixt Solid and Fluid Bodies, seems to consist in this, viz. That the Parts of Solids are at rest, and not so apt to yield to the Pressure of One's Finger, as the Parts of Liquids' are, which are in Motion; since the Latter being already agitated to and fro, it is much more easy to guide that Motion, than to put the Parts of a Body into Motion; whose Parts, according to the Laws of Motion, must be at rest, till moved by an Agent powerful enough to put them into Motion. But when once they are put into Motion, by the same Laws, they must continue so, till stopped by some other Body; and consequently, they must be in a perpetual Change, as to their Places and Orders: so that hence it appears, why some Bodies come to be so soft, since such small Parts of Matter, being in Perpetual Motion, must needs yield very easily to the Touch, and give way to the Impressions of other Bodies. And also, it cannot but dispose them easily to be confined by the Vessels they are contained in, and as apt to disperse themselves, when Liberty is given them. Having premised this Brief Account of Fluidity, I shall now proceed to illustrate it by Experiments: And first, by that concerning Salt-Petre. The Doctrine of Fluidity illustrated by Experiments. Salt-Petre then may become a Fluid Body, either by having the Particles of it dissolved in Water, so that they may move up and down, and to give way to the Impression of an External Agent, as the other Parts of that Liquid do; or it may put on a Liquid Form, by being exposed to the Air in a moist Cellar, where by running per Deliquium, the Salt-Petre will be dissolved, and put on so far the Form of a Liquid, as to have all its Parts in an Agitation, sufficient to rank it amongst Fluid Bodies. But Salt-Petre may put on a Liquid Form, without the Addition of a Liquid Body; as first, It may be reduced to so fine a Powder, as to resemble a Liquid, in the pouring of it out of one Vessel into another, besides the other Requisites of a Fluid Body; viz. That it hath Vacuities betwixt its Parts, and that they may be easily put into Motion; only they differ from the Parts of Liquids in some Respects, since the Powder hath not its Parts always in Motion; besides the Vacuities are more sensible: But notwithstanding, if by the force of Fire each of these Parts be again subdivided, those insensible Corpuscles, being violently agitated, make up a Fluid Body: So the Particles of Metals, being by the same Agent separated and put into Motion, do not only move variously one amongst another, but are sometimes tossed a considerable height into the Air. And not only Fire, but some other Bodies, which are sensibly Cold, may, provided the Texture and Motion of their Parts be rightly disposed, reduce several Substances to a Liquid Form; so Camphire puts on the Form of an Oil, when swimming upon Aqua fortis: And when Salt-Petre is by the Action of Fire, endowed with a Fluid Form, it is equally a Fluid, as when incorporated with Water, there being very little difference betwixt these two States of Nitre; only that in the Former, the Agent, which keeps the Nitrous Parts in Motion, is more Volatile and Brisk, and divides it into smaller Parts, without making an Addition to its Bulk. But, perhaps, it will be a Scruple, Whether the Powder of Nitre be an Imperfect Fluid, when poured out, or rather like a heap of Sand, not reduced to a permanent State of Fluidity: To remove this Scruple, we may take Powder of Alabaster, or instead of it, Plaster of Paris, and we shall find, that by putting it into a hot Vessel, by the continued Action of the Fire, the Parts of that Powder will be so agitated, and, by the Assistance of the more Spirituous Parts, kept in Motion, as to Boil and emit Steams like a Fluid Body, and altogether resemble a Coherent Substance; yet, if it be removed from the Fire, it again subsides in the Form of a Powder, tho' for once again it will assume the Form of a Liquid, if exposed to a competent degree of Fire; yet when the Ebullition of the Parts of it are most violent, if a small Portion of it be thrown upon a piece of Paper, it appears to be nothing but a very fine Powder: From whence it is evident, that Fluidity depends on a vehement and various Agitation of Parts; which Fluidity the same Body may be deprived of, by losing that Intestine Motion. What the Motion of the Parts of Fluids' depends on. And thus it briefly appears how much Motion contributes to the Fluidity of Bodies. And here, tho' it would be very desirable to determine what is the Essential Cause of that Motion; yet since it is a Matter of too much Intricacy, it being by some held to be inherent in Matter, and by others to be promoted by Impulse, I shall rather pass it by, than enter upon an Examination of those two Points; especially, since there would be the same Necessity of Discussing others, which equally relate to the Cartesian Principles: It may therefore suffice in short, that neglecting the Unintelligible Doctrine of Substantial Forms, we rather ascribe it to those Catholic Affections of Matter, Motion, Shape, and Situation. But to omit what we have elsewhere delivered concerning these Catholic Affections of Matter, we shall observe, what this Experiment further affords us: We are therefore to take Notice, That there is a difference remarkable betwixt a Fluid, and a Body which hath a Quality of Wetting Bodies which are Contiguous to them; since every wet Body is Fluid, but not vice versâ: For Air, Flame, Melted Liquors, or Salt-Petre, tho' fluid, are all void of a Wetting Quality. Humidity a Relative Quality. Whence we are led to consider, That Humidity is but a Relative Quality, depending on the Congruity that one Body hath to stick to the Pores of another; whence some Fluid Bodies, whose Parts are not adapted, so as to adhere to the Pores of other Bodies want that Quality, as Quicksilver, which slips over the Surfaces of most Bodies, without sticking to them; tho' in Respect of some (as Gold or Tin,) it may be esteemed Fluid; since, inasmuch as it dissolves them, it hath much the same Virtue as Liquids have in softening other Substances: And that Humidity depends on an apt Configuration of the Parts of Matter, and their Congruity with the Pores of other Bodies, is further evident, since Water itself, in respect of some Bodies, is not moist as the Feathers of Swans, Ducks, etc. Add to this, That it is further observable, that when the Texture of a Liquor is changed, it may adhere to Bodies it would not stick to before: As for Instance, Tho' neither Quicksilver, Led, Tin, or Tin-glass, will stick to Glass; yet a due Proportion of each mixed together will presently, without the Assistance of Fire, adhere to it. That the Pores of a Body cannot be perceived no Argument of their Nonexistence. But further: If it be objected, That the Insensible Agitation of the Parts of Fluid Bodies, are but Imaginary and Precarious; since the Smallness of them, makes them too fine to appear: I must answer, That since their Vacuities, are so small as not to be Visible, it is as impossible to discern their Parts, and consequently the Motion of them; since one Part is so presently succeeded by another, that the Eye hath always a whole heap before it, tho' separated by Pores so small as to be undiscerned. And tho' the. Vacuities betwixt the Parts of powdered Nitre, be so large, as to be discerned by the Eye; yet when its Corpuscles, by the Action of the Fire, are rendered more Minute, not only Salt-Petre, but Gold also, are said to possess a less Space, and consequently must leave less Vacuities betwixt their Parts, and which are altogether Invisible to the Eye: For which reason the Body appears continuous. The Motion of the Parts of Liquids' variously determined. And that the Particles of Fluid Bodies, are in Motion, variously determined, appears from their Effects; since they not only penetrate, but putrify some Bodies, and presently dissolve them; as when Sugar is cast into Water, that sweet Substance is dissolved, and its Parts so much associated with those of the Water, as to be carried up to the Top of it; which is further observable in Sea-water, whose Salts upon Evaporation swim at the Top of the remaining Liquor; and it is not less remarkable, That a Solution of Gold in AquaRegis, will presently Tincture twenty times as much fair Water: And further, That the Particles of Flame may be discerned to move very fiercely, even by the Eye, is commonly known, and further confirmed, both by their Operations, and the Rays which every way expand themselves, and strike against the Neighbouring Bodies. And that the Air hath its Parts in a constant Motion, variously agitated, we have ä great deal of Reason to believe; since we may easily discern whole swarms of Motes swim up and down in the Sunbeams: and not only so, but in clear Sunshine Days, we may perceive on the Walls of Churches, and other Spacious Buildings, certain obscure Shades to quiver and tremble: And we have yet a further Instance in Salt of Tartar, which, after Fusion, being for a considerable time left in a moist Cellar, will dissolve, and put on the Form of a Clear Liquor, by imbibing the Moistness of the Circumambient Air, which penetrates, and gets into the Pores of the Salt by an Intestine and Powerful Motion. And it is further to be Noted, That if in Summer, cold Water be put into a Glass, the moist Vapours which move about it, will be condensed on the outward side of the Glass, and appear in the Form of Dew, those Moist Particles, which swim in the Air, being, by the Perpetual Motion of its Parts, successively driven upon the External Superficies of it: In trying of which Experiment it is Remarkable, That the Dew on the outside, was not to be observed above the Surface of the Liquor contained in it. And these Relations are the less to be wondered at, if we consider, that so weighty a Body as Led, may be raised in the Form of Smoke, a considerable height into the Air, by the Assistance of proper Vessels, placed in a convenient Furnace; which Smoke, will be soon scattered and dispersed, by the Various Motion of Aerial Particles: And this Experiment does not only show, that the Parts of Air are in a Perpetual Motion, but also how much the Minuteness of them contributes to their Fluidity. And tho' Quicksilver much exceeds any other Body in Weight, except Gold, yet it's Minute Parts, agitated and raised in the Form of a Vapour, will, like other small Particles of Matter, glide to and fro in the Air; whence it hath oftentimes happened, that in Evaporating of it, several pieces of Gold have been so whitened over with the Fumes of it, as not to be got off again without a great deal of Trouble. But to make it almost Visible, that the Parts of Liquid Bodies, are perpetually in a variously determined Motion, mix a Solution of unrefined Silver in Aqua fortis, with 15 times its Proportion of Fair Water, Decanting or Filtrating the clear Mixture: In which Liquor the Parts of the Silver are not in the least discerned, tho' upon Immerging a Copperplate into it, the Particles of that Metal, which before swum up and down in the Mixture, presently adhere to the Copper, and crust it over with a Metalline Powder; and if the Copper Plates remain in that Liquor for a Night, the whole scattered Corpuscles of Silver will be collected together about them, the Liquor being Tinctured with a Blue Tincture, by some Parts of the Copper, corroded and divided into Parts, by the Salt Parts of the Aqua fortis. And to render this Experiment still more Useful, I have observed, That by letting a piece of Spiltre lie in this Tincture for some Days, the Copper Particles were gathered round about that also, from all the Parts of the Liquor; which could not be, were not the Water in a Perpetual Intestine Motion; so that its Parts might, by often changing their Places, successively strike against the Spelter, and so leave the Silver behind. To this Experiment may be added another, which I have long since tried, when first I began to consider the Reason of Fluidity. I dropped then, into Spirit of Wine, moderately Deflegmed, a small quantity of Oil of Turpentine, letting it fall so far, that it might by the force of it be broke into small Drops, which by reason of their Tenacity, being unapt to mix with the Spirit, would swim upon it, and be moved up and down, variously and irregularly, by the Spirituous Parts of the Liquor, which struck against them in their Ascension; and whilst these Spirituous Parts continue to exhale, it is pleasant to behold, how the Globous Parts of the Oil will sometimes be gathered together, and almost unite, and presently after, be again dispersed abroad, and move to and fro amongst one another; and this Motion would continue, till the most Agile and Spirituous Parts of the Liquor were wholly spent. And lest this Motion of the Oily Parts, should be suspected to arise from some Antipathy betwixt it and the Liquor, I tried the Experiment with small chopped Straws, which were likewise impetuously, and confusedly moved up and down on the Superficies of the Spirit: From whence we may learn, That there may be an Intestine Motion of the Parts of a Liquid Substance, tho' it be not discerned by the Eye. I might here reckon up a great many more Phaenomena exhibited by this Experiment; but it shall suffice to take Notice, besides what hath been already delivered, That some of the aforementioned Spirit, being closed up in a Glass, Hermetically sealed, to try whether the Oily Drops would continue their Motion, when the Vinous Spirit could not exhale, the Vessel was presently broke, without any force otherwise discernible, than by the effects of it. And that the small Parts of the most weighty Liquors, are actually in a Continual Motion, may not only appear from what hath gone before, but may be further confirmed; since Quicksilver will not only penetrate into the Pores, but destroy the Texture of so solid a Metal as Foliated Gold: And Salt of Tartar, tho' cold, is able to extract Tinctures from several Bodies: And that the Parts of Oil of Vitriol are in a Perpetual Motion, may be evinced, by the Corrosive Qualities of it, which it powerfully exerts without the Assistance of Heat, not only in Corroding Metals; but if pieces of Camphire be thrown into it, they are presently turned into an Oily Substance. And whoever is unwilling to believe that there is an Intestine Motion of Parts in these two Oils, may easily be undeceived, by the Heat and Ebullition, which follows upon the Mixture of them agitated together in a Glass. But here we are to observe, that tho' it be an Essential Property of Fluid Bodies, that one Particle readily gives way to another; and that the other is as apt to succeed in the Place of it interchangeably; yet that is not to be conceived of all Fluid Bodies in General; but is to be understood only in such Bodies, as are either Simple and Homogeneous, or as have an Aptitude to mix with each other, as Wine and Water; since there are some Liquid Bodies, which will not be mixed together; but like compact Substances, resist the Impressions of each others Superficies; and it is not a little strange that Lucretius and some other of the Ancient Atomists should overlook so obvious an Observation, since it is apparent in Oil, which will not mix with Water; but more eminently in Quicksilver, which denys to mix any of those Liquors which were familiar amongst them. But to add an Experiment which is more remarkable, having so prepared and opened the Body of Copper with a sufficient Quantity of Sal Armoniac, as to render the prepared Mineral inflammable; I applied some Grains of it to the Wiek of a Candle, by the force of whose Flames it was not only Melted, but carried up along with the Tallow to the Bottom of the Flame; where it was observable, that the Flame of it was both lasting, and as distinct from that of the Candle, as if the two Flames had been separated by the Interposition of some other Body. Why some Liquids are unapt to mix with each other. But to return to what I have said of the unaptness of Liquors to mix with one another, the reason in general seems to be no other than the particular Texture and peculiar Motion of their Parts. And this I am the rather induced to believe, because Salt of Tartar, dissolved by the moistness of the Air into a Liquid Form, will readily mix with Spirit of Wine, the Texture being only changed by an addition of Water; tho' before, they both had their distinct Superficies; and tho' mixed by a Violent Motion, yet would presently separate again, and each regain its former Position. And Oil or Spirit of Turpentine, gently drawn off from Sea-Salt, Melted or well Decrepitated, will readily mix with Spirit of Wine, though there was no sensible difference betwixt that Oil and another which would not. Again, a Solution of Salt of Tartar, digested for some time with Oil of Almonds, would be turned into a soft Saponary Substance; tho', by a strong Agitation, Lixivial Liquors cannot be mixed with Oils. Moreover, tho' cold Quicksilver will not mix with Oil of Vitriol, yet, the boiling Oil will, by piercing its Substance, both altar and incorporate with it. The Superficies of Liquids by pressing one against another, give each other a determinate Figure. There remains one thing, yet to be taken notice of concerning the Difference in fluid Bodies, which is, That some of them, which will touch each others Superficies without Mixture, will also reduce them to a determinate Shape. As for Instance, if Spirit of Wine be poured upon Oil of Tartar per deliquium, tho' the contiguous Superficies of both be parallel to the Horizon, yet the upper Superficies of the Spirit will be endued with a visible Concavity, if the Experiment be tried in a slender Glass unstopped. In which Liquors it may be further noted, that upon a Mixture of Oil of Almonds, it presently separated the one from the other, the Superficies of the Oil of Almonds contiguous to the Oil of Tartar, being Level as well as that, which was next to the Spirit of Wine: But if Oil of Turpentine be poured upon it instead of Oil of Almonds it will be divided into several Portions, some of which Swimming in the Spirit of Wine, will be of a Globular Figure, and others which rise to the top of the Liquor, will be partly Levelly with the Superficies of the Liquor, and partly Spherical, on the immersed Superficies. And it may be yet further observed, that some Globular Parts would, tho' the Liquor was shaken, continually Swim upon the Oil of Tartar, being contiguous to it only in a Point. But what is more Remarkable is, that several drops of Oil of Turpentine falling into the Spirit of Wine, lay upon the Superficies of the Oil of Tartar, like so many Hemispheres, their convex Superficies being upwards; yet by degrees they became Globular, being equally pressed on every side, and touching the Oil of Tartar only in a Point. And these Experiments I have the rather recited, because, they being added to that which may be observed in the Torrecellian Experiment by suspending Mercury in the Air (by admitting Air into the Glass Tube, so as to separate the Mercurial Pipe into several Short ones, which will have on each side a Superficies something convex) because I say, they might be of Use in Accounting for the different Configurations of Fluid Bodies, as well as the distinct Superficies of those Vapours which Swim in our Atmosphere. A Transparent Liquor may yield a Liquor Diaphanous and another Opacous. Having said thus much of Fluidity, it may not be amiss to subjoin one Experiment which shows, how a transparent Liquor may be divided into two, the one Diaphanous, and the other Opacous. Pour into a warm Solution of an Ounce of Quicksilver with a double Quantity of Aqua Fortis, about half an Ounce or an Ounce of Filings of Lead, being cautious that it be not put in so fast, as to make the Liquor Boyl over; the Event of which will be, that the Lead will be immediately precipitated in the Form of a white Powder, the Mercury running together again into a Fluid Body immersed in the Aqua Fortis. And here it is to be noted, that if the success of this Experiment be frustrated, the Mercury may by degrees be again recovered if the white Precipitate be diligently ground for some time with Water. Motion in the Parts of some Consistent Bodies. But to put a Conclusion to this Chapter, it is highly probable, that not only Fluid, but some consistent Bodies have their Parts in a certain degree of Motion; whence, as we may conjecture, proceeds that Dust which is the Effect of Putrefaction, in some sorts of Wood: And it is not absurd to imagine, that from hence Worms in Fruit as well as Maggots in Cheese derive their Original. And that there is Motion amongst the Parts of some consistent Bodies, is further made probable, both by that Turpentine which I have observed to Sweat out of Deal Board's, and the growth and increase of the Bones, and other consistent Parts of Bodies; but more particularly in those of colder Animal Substances; as Oyster-Shells, Crabs-Claws and such like consistent Substances. Having said thus much concerning Fluidity, it might not be improper to take notice how by the Mixture of Liquids', their Fluidity is sometimes promoted, and also sometimes destroyed. But since we shall have occasion sometime or other in the following Chapter, to make such Observations; I shall, to close this Chapter, add an Experiment, which may intimate, that the event of Mixtures is not always certain: The Experiment is the following; We Evaporated a Solution of Copper in Spirit of Nitre, from whence we obtained a Vitriol of a lovely Colour: We likewise dissolved one Part of good Tin in a double Quantity of Spirit of Nitre; and tho' Salt-Petre as well as Tin, be both Fusible, yet this Metalline Mixture would neither melt on quick Coals, nor in a red hot Crucible: Whereas the Vitriol of Copper would melt with the heat of ones Hand, though the Metalline Ingredients be much more hard to be brought to Fusion than Led, or even Silver itself; and we have sometimes obtained such a Vitriol, as might be preserved in a Fluid Form by the Languid heat of the Sun in Winter, either with Spirit of Nitre or a certain Aqua Fortis: From whence it appears, that the Textures of Compositions are to be considered, as well as the Particular Consistence of the Ingredients. CHAP. XII. Experiments concerning the Superficial Figures of Fluids'. Especially of Liquors Contiguous to other Liquors. COnsidering that the greatest Part of the Universe, is made of Fluid Bodies, especially if according to the Cartesian Hypothesis, the Sun and fixed Stars consist of Fluids', it may not be amiss to illustrate, what we have only hinted at in the foregoing Chapter: For the following Experiments made about the superficial Figures of Fluid Bodies, may not a little contribute to illustrate, as well what hath been before delivered, as what hath been said concerning the Pores of Fluid Bodies; besides, they may be of no small use, in accounting for several Phaenomena belonging to the Grand System of the World. EXPERIMENT I. and II. The Figure of the Surface of a Nitrous Liquor. To try whether the concave Surface of Fluids', contained in a Pipe, was wholly to be attributed to the Pressure of the Contiguous Air, I poured Dephlegmed Spirit of Wine upon a strong Alkalizate Menstrum, which was made of fixed Nitre run per deliquium in a moist Cellar, and contained in a Cylinder of Glass of about a quarter of an Inch Diameter; I found that the Menstrum changed its concave for a horizontal Superficies; and the like succeeded in a Glass of a much greater Diameter. And that Superficial Cavity was likewise almost destroyed by pouring on Oil of Turpentine instead of Spirit of Wine. EXPERIMENT III. Of Water. If instead of the former Liquor, common Water was put into the Glass Cylinder, it retained its former Surface, tho' Oil of Turpentine Swum upon it instead of Spirit of Wine. EXPERIMENT IU. To try what Surface would be made by an Oil heavier than Water, Of Oil of Turpentine. by being contiguous to it, I put pure Oil of Turpentine into a Glass Cylinder, and found that the Concave Superficies which it had whilst the Air was Contiguous, became Convex and protuberant upon an Affusion of Water. EXPERIMENT V. The Superficies of a Solution of Tartar, etc. Again having put Salt of Tartar deliquated into a Glass Cylinder, and poured Oil of Guajacum upon it, we found, that the Concave Superficies was not altered as it was by Oil of Turpentine: And having gently poured Water upon these two, the Oil of Guajacum Swum betwixt the Water and the Oil of Tartar, having a Convex Superficies at each end, that next the Oil of Tartar being most protuberant. EXPERIMENT VI. Of Oil of Cloves. Having likewise put Oil of Cloves into a Glass Cylinder; by pouring Water upon it, it's Concave Superficies presently became Convex; and this Oil being too heavy to Swim upon Water, we poured some of it upon Deliquated Salt of Tartar, pouring upon it likewise a little common Water, which being done we found the Oil Protuberant at both Ends, but more at that which was Contiguous to the Water. EXPERIMENT VII. Again, having put a considerable Quantity of Quicksilver into a Pipe of the same Diameter, Of Quicksilver. but much longer than the former; we found, that the Superficies of it, which was otherwise considerably Protuberant, was in some measure Depressed, when Water instead of Air was Contiguous to it. EXPERIMENT VIII. Of the same. Upon trial, whether a greater or less Quantity of Water would alter the Surface of the Mercury, I found that the greater the Quantity of Water was, the more it was depressed; tho' it did not always succeed: But when the Cylinder, being of a considerable length, was filled with Water, the Mercury Contiguous to the Glass was depressed to a Level; having, in the Centre of its Superficies, a Protuberance Semicircular and raised above the other level Surface half its Diameter, which Protuberance gradually subsided as the Mercury was drawn off. EXPERIMENT IX. The Surface of Liquors in Vacuo Boyliano. Having conveyed two of the Cylinders, one containing Water, and the other Mercury into our Pneumatical Receiver, we found that, notwithstanding the Air was not Contiguous, the Superficies of the Water was not manifestly altered by the Exsuction of the Air, tho' the Mercury seemed sometimes to be a little more Protuberant, especially when the Exhausted Air was let in with any Celerity. But one thing in the Mercury, which was observable; was, that upon the Exsuction of the Air, several Bubbles seemed to rise in the Mercury, and how much those might conduce to the mentioned Phaenomenon, we leave others to try. Again, having conveyed another Cylinder into our Receiver, which contained an Oil, whose Superficies, when Water was poured upon it, was Convex; we found, that upon the Exsuction of the Air, neither the Oil lost its Protuberant, nor the Water it's concave Superficies: From which Experiments it may appear, what Effects the Pure Aether would have upon such Bodies, were they removed out of this Atmosphere. EXPERIMENT X. Though the Figures of the Parts of scattered Fluids, and of condensed Vapours, be usually Globulous; yet those Observations being too Transient, to deduce from them the Figures of the Parts of Fluids', we tried the following Experiment, that I might observe something more Remarkable: Having mixed Fixed Nitre, dissolved into a Liquor by running per deliquium, with exactly rectified Spirit of Wine, and found that, those two Liquors, tho' shaked together, would retain distinct Surfaces; I dropped Oil into the Spirits, which gradually subsided till it touched the Superficies of the Nitrous Liquor. The Phaenomena exhibited by this Experiment were the following. Phaenomena exhibited by a Nitrous Liquor and Spirit of Wine. I. That if the Drops were small, they retain an exact Spherical Figure, being neither depressed by their own weight, nor the gravity of the ambient Spirit, the Oil being much of the same specific Gravity with the Spirit of Wine. II. If an Aggregate of Drops were a quarter of an Inch in Diameter, the Pressure of the upper Parts would depress the lower so much as to form a Plain on that side Contiguous to the Nitrous Liquor, so that the Horizontal exceeded the Transverse Diameter in Length. III. And if the Quantity of Oil was greater, it would so depress the lower Parts, as to form an imperfect Hemisphere, the lower Part of it having its plain and horizontal Superficies, parallel to that of the Superficies of the Nitrous Liquor. IU. But if the Oil poured in, was moderate as to Quantity; tho' at the first it would spread over the Surface of the Nitre, yet, by degrees, it would be compressed and be so raised, as to form either an Hemisphere upon the Surface of the Nitrous Liquor, or a Segment of a Globe, or even of an Imperfect Ellipsis; to the production of which Phaenomenon the Tenacity of the Oil, as well as the Ambient Spirit in some Measure contributed. V Tho' these Globules of Oil would sometimes readily mix and associate, when brought together; yet, for the most Part, they would make an Impression into one another without uniting, and again recover, their former Figure when permitted to separate. VI It was not unpleasant to behold, how if a large Quantity of Oil was poured into the Spirit, the Convex Superficies of it would acquire various Figures upon the Motion of that Ambient Spirit; and if the Agitation was strong, several Parts being broke off, would form as many Aggregates of a Globular Figure. EXPERIMENT XI. Of Oil of Turpentine Having put a Mixture of two Oils, one of which was drawn from Turpentine, into other Liquors, to try whether the Lighter Oil would separate from the heavier, with which it was incorporated; I found, that tho' it answered not my Expectation; yet as the Quantity of either of the Oils was prevalent, the Mixture would either sink or swim, in the Liquors it was put into. And to the Phaenomena exhibited by Oil of Turpentine, it may be added, That when part of it is contiguous to the Liquors it is put into, and part adheres to the Glass, the Superficies contiguous to the Water is of Figures too various and extravagant to be described. EXPERIMENT XII. Several Colours exhibited. It is to be noted, that when the Nitrous Liquor is very clear, it will, in the former Experiments, be very difficult to discover where the Surfaces of the two Liquors are contiguous, they both appearing to be one and the same Mass, except some Dust swims upon the Nitrous Liquor, or the Rays of Light fall obliquely upon it. EXPERIMENT XIII. Having poured a peculiar sort of Oil upon a Deliquation of Nitre and Tartar, tinged with Cochinele, I observed, that by holding the Mixture in a certain Position, the plain Superficies not only variously refracted the Incident Beams of Light, so as to represent several vivid Reflections, but the plain Superficies appeared almost as convex, as that of Quicksilver; and it was further to be observed, That it almost as strongly reflected the Rays of a Candle, as a Close Specular Body usually does; which Phaenomenon could not proceed from the Alkali altogether, but might partly from the Concurrent Action of the Oil, which I observed to contribute to Refraction, when mixed with other Liquors; but I shall not here endeavour to determine, what was the Cause of the Forementioned Phaenomena; but in order to it shall observe, First, that neither the Confining Plain, which separated these two Liquors, nor the Superficies of the Nitrous Liquor, was the Occasion of that Red Colour, which the Flame of the Candle acquired. Secondly, the Liquor being chafed, the uppermost would be turned into a Froth, consisting of Bodies imperfectly Globular, which in a little time would form a rude Physical plain, the Upper Superficies of which, would reflect the Rays of Light very briskly; and when the Parts of the Froth became a little finer, they would reflect the Rays of a Candle, so as to represent so many pieces of Silver polished, or a Copper Plate freshly immersed in a Solution of Silver in Aqua fortis: To which Phaenomena a Third may be added, viz. That the confining Surface of the aforementioned Oil upon Spirit of Wine, was not a little strongly reflective. Most of these Phaenomena before mentioned, were afforded, by making use of Oil of Lemons instead of the former, except that the Reflection was not so brisk. EXPERIMENT XIV. Of Oil of Aniseeds. Having poured Oil of Aniseeds dissolved by a Moderate Warmth, upon warm Water, contained in a Viol, I found that the Upper Surface of the Oil, as well as that of the Water was Concave; tho' the Lower Superficies of it was very Protuberant and Convex; and when it had been removed for some time into a Cold place, so that the Oil might be Coagulated, the Convex Superficies of the Oil was something less protuberant: So that it seemed to resemble a Concavo-Convex-Glass made use of for Dioptrical Purposes. EXPERIMENT XV. It is not only observable in the former Liquor, that the Oil caused a much more vivid Reflection, in a Fluid than Consistent Form; but it may be further noted, That even the Shining Reflection of Quicksilver, may be increased by the Addition of a Liquor: For if Distilled Mercury be put into a Viol, and Petroleum be gently poured upon it, the Reflection will be sensibly increased by the Addition of that Liquor; but whether that Reflection proceeds from some Subtle Body included betwixt the Petrloeum and the Mercury, I shall not determine; only to make it probable, That were there such a Body included it might much contribute to such a Phaenomenon, I shall add, That I once saw a Transparent Body, which was supposed to have a true Oriental Pearl in it; but upon the Breaking of it, that which was supposed to be a Pearl, was nothing but a Cavity containing a Substance, something grosser than Air: And I have a piece of Glass by me, which hath Air included in a Cavity of a Pearl-like shape, which causes such a vivid Reflection, as to resemble a fair Pearl. And I am Master of a Small Stone, which looked upon in one's Hand directly down, seems to be like Common Glass; but if the Beams of Light in another posture fall upon it obliquely, it appears to be a fine Opal, or Oriental Pearl. EXPERIMENT XVI. An Experiment in Vacuo Boyliano. Having melted a Gummy Substance in a deep round wide-mouthed Glass, and conveyed it into our Pneumatical Receiver; upon extracting the Air, we found, that which was contained in the Pores of the Gummy Substance, to rise in Bubbles, several of which settled at the Top, and others were detained in the Body of it, upon the Cooling of that Substance: Where it was to be observed, that those which were included in the Gummy Substance, did not only cause a considerable Reflection, but also the Air was so rarified in them, that upon the intro-admission of external Air into the Receiver, those Bubbles, which were raised to the Top, and adorned with Curious Colours, like those of a Rainbow, were presently broke: EXPERIMENTS XVII, and XVIII. Of Water included in Oil. Tho' it is usually thought, That the Parts of Water are Spherical, in falling Rain; yet since Hail, which is nothing but Drops of Water froze, and often of a Figure different from Orbicular; to be further satisfied concerning their Figures, we conveyed several Portions of Water into Oil of Cloves, and found, that one which was as big as a Pea, was so near an Orbicular Figure, as to approach an Elliptical one; and other Portions of Water, which were larger, were somewhat Elliptical, but rather more depressed in the middle; and these Phaenomena were afforded by those Portions of Water which were only contiguous to the Oil and Air. EXPERIMENT XIX. Having put Oil of Turpentine upon Oil of Cloves, which was contained in a Glass Cylinder; I observed, that Water being encompassed betwixt these two Heterogeneous Bodies, the Surface of the Oil of Cloves was but a very little protuberant; And the lower Surface of the Oil of Turpentine, was but moderately Convex. EXPERIMENT XX. Of Coagulated Oil of Aniseeds. To try whether Fluid Bodies would retain their smooth Surfaces, when reduced to a Solid Form, I left Oil of Aniseeds to coagulate upon Water, and found that that Superficies, which was Contiguous to the Air, as well as that which was next the Water, had each a peculiar kind of Roughness. EXPERIMENT XXI. Having exposed one Portion of Water to be froze, with Oil of Junipers upon it, and another with Oil of Turpentine; I found that the Ice, which was under each, had a different and peculiar Surface: A Variety of Surfaces may likewise be observed upon several frozen Liquors, which abound with Water. And I have observed myself, in a red Decoction of Soot of Wood, set to freeze, Crystals shaped like Daggers, curiously embossed, as well as fringed at the ends. EXPERIMENT XXII. And besides the Irregular Surfaces of a frozen Liquor, contiguous to a Heterogenous Body, I have observed in Oil of Vitriol, that Part of it being froze, the Superficies, which was contiguous to the Liquid Part, was very unequal with several Asperities. EXPERIMENT XXIII. And not only Bodies, which are Naturally Fluid, but those brought to Fusion by Art, acquire Various Sufaces upon their putting on of a Solid Form; For I have observed, upon the Surface of a Regulus Martis Stellatus, and a Regulus of Antimony without Mars, Curious Embossments of the Figure of a Star; but if to these Body's Copper be Artificially added, they acquire New Surfaces, sometimes resembling a Net: And I have now by me, a Mass of a Conical Figure, consisting of two Parts, contiguous to each other, which when separated, the lower Part had upon its upper Side, a great many Protuberances; and the Conical Part on its Superficies, which was contiguous to that, was furnished with Cavities answerable to, and adapted to receive those Protuberances: Whence it might be inferred, That the more Metalline Part, which was embossed with those Protubetances, was first hardened, and the other more scorious and recrementitious Part, was afterwards adapted in its Coagulation to the Protuberances of that which would melt with the Heat of ones Hand, tho' the Metalline Ingredients be much more hard to be brought to Fusion than Led, or even Silver itself; and we have sometimes obtained such a Vitriol, as might be preserved in a fluid Form by the languid Heat of the Sun in Winter, either with Spirit of Nitre or a certain Aqua fortis: From whence it appears, that the Textures of Compositions are to be considered, as well as the particular Consistence of the Ingredients. CHAP. XIII. Containing the History of Firmness. ALTHO' the Compactness and Solidity of Bodies, is usually attributed to the Coagulating Qualities of a saline Ingredient, by the Chemists, yet since their Explications are not intelligible, I shall proceed to inquire after another Cause. First then The Solidity of a Body being a Quality contrary to Fluidity, A Definition of Solidity. seems to consist in this, viz. That the gross Parts of solid Bodies are so entangled and interwoven together, that they are unapt to diffuse themselves several ways, like fluid Bodies; and that the Figure of their Superficies is rather to be attributed to the Connection of the Parts that compose them, than to the Impressions of outward Bodies. In which Definition these three Things appear to be the Causes of Solidity, viz. Grossness of Parts, Rest, and the Implication of the constituent Parts. The Grossness of the Parts of a Body contributes to its Solidity. And First, That the Grossness of the Parts of a Body contributes to the Solidity of it, is evident from what hath been already said of Fluidity; for if Minuteness of Parts is requisite to produce such a Quality as Fluidity, it must follow that the Inaptitude that is in grosser Matter to be put in Motion must be a further Argument, That the Grossness of Particles is conducive to Firmness. But here it is to be noted, that by Grossness or Minuteness of Parts, I would not pretend to decide the Controversy, Whether Bodies may be indefinitely divided into smaller Parts; but I would only intimate, that tho' mentally all Bodies may have an indefinite Divisibility, yet the Parts of solid Bodies are made up of a Number of such minute Parts, as convening together form those grosser Corpuscles, which, when united, are not to be dissolved by the external Impressions of ambient Air or Aether, or any thing else, usually reckoned amongst the Causes of Fluidity. Secondly, It is to be noted, That tho' I have said, that the Grossness of Bodies contributes to their Firmness, yet I would be understood to mean, caeteris paribus; for the gross Parts of a Body, by being broke and divided into smaller, may be so disposed, to lie nearer one another, so as upon their more close Union, to put on the Nature of Firmness more conspicuously, by affording a more full Contact to other Bodies, especially, if those minuter Parts be so adapted, as to leave smaller Pores betwixt them. But this being evident from what hath gone before, I shall pass on to Rest contributes to the Solidity of Bodies. The other Requisite for the producing of solid Bodies, viz. Rest, which, tho' it is taken notice of by the Ingenious Des Cartes, yet since it is not confirmed by Experimental Philosophy, I shall here illustrate it a little further; first observing, that it is agreed on to be one of the Laws of Motion, That when a Body is at rest it will continue to be so, till forced to move by the Impulse of an outward Agent; and whatever may be urged by some Atomists, concerning the Adhesion of the minute Parts of Matter, yet, that a Juxta-position of Parts is sufficient, without the Addition of a Cement, is evident; since several Pieces of Glass, if exactly fitted and polished, will adhere so firmly together, that by lifting up the uppermost the rest will adhere so closely as to be raised with them; which will also succeed, if two Marbles exactly polished and ground, have their Superficies applied to one another; and it is further remarkable, that if two Glasses be rubbed one against another, the one will be suspended at the other, without any visible Prop to support it, and preserve it from falling. But here it may be necessary to take notice, that an exact and level Superficies is not always requisite to make the Experiment succeed, since a concave and a convex Glass rightly adapted will adhere with the same degree of Cohesion; an Example of which we have had in a Glass Stopple, duly adapted to the neck of a Bottle; by which the Bottle, containing a Pound weight of Liquor, might several times be lifted up from the Table; which could proceed from nothing, but the close contact of those two Bodies; unless it be urged, that by pressing the Stopple down the small Asperities of the one might be squeezed into the small Pores of the other. A Juxta-position of Parts, not the only Cause of their Adhesion. But tho' from hence it may be argued, that a bare Juxta-position is sufficient to account for the Cohesion of the Parts of some Bodies, yet it is not to be denied, but that their strict Contact may be promoted by the Spring and Pressure of the Atmo-sphere; since by reason of their Juxta-position, the Air, which presses upon the lower Superficies, hath not an equal Pressure to balance it on the other Side of the same Piece; it being immediately contiguous to the lower Superficies of the Piece adjoined to it; by which Means the Pressure of the Air resisting the Gravity of the Glass, instead of tending towards the Centre it is buoy up and pressed against the upper Piece, just as if a Board were pressed with one's Hand against the Ceiling of a Room, which will continue in that Place as long as the Pressure with ones hand is continued: And indeed, That the Air does so press upon the lower Superficies of Glass is but the natural Effect of the Weight and Spring of it, which being bend and pressed together, by the Weight of incumbent Air, will naturally recoil and fly back, from the Superficies of the Earth, upon any Body which is in the Way to be pressed upon. The Weight and Spring of the Air may contribute to the Cohesion of Parts. To confirm this Conjecture I shall add, that if a Piece of Glass be stuck to the Superficies of a Looking-glass parallel to the Horizon, it will stick fast to it, except it be moved by one Hand; but if the Horizontal Superficies be inclined, the smaller Glass will readily slip from one Side of the greater to the other, accordingly as it is differently inclined. The Reason of which is, partly because the Gravity of it does not resist the Horizontal Motion, but only that which tends from the Centre; and partly, or chief, because the Pressure of the Air on both Edges of the Glass is equal, and consequently its own Gravity makes it tend either this or that way, as the Glass is variously erected or inclined; whereas the Superficies adhering to the Looking-glass receives no Pressure proportionable to the Pressure of Air recoiling against the lower Surface. And for a like reason, if the neck of a glass Viol. full of Mercury be immersed in fluid Quicksilver, the Bottle will continue near full, as long as the neck of the Glass is immersed in the Quicksilver, tho' it be several ways inclined; the Reason of which seems to be, only the Pressure of the external Air upon the Surface of the Mercury; by which Means it is forced up against the Surface of the inverted Glass, so that for want of an equivalent Pressure upon the Mercury in the Glass it is kept from subsiding; for that it does not proceed from Nature's Abhorrency of a Vacuum is plain, from what hath been tried concerning the suspended Mercury in the Torrecellian Experiment; and that it may appear more fully, that the Exclusion of Air, as well as its immediate Contact, contributes to the keeping of Bodies from falling asunder, it will suffice to relate, that having sucked a good Quantity of Air out of a Bottle, and applied a Book which was next at hand to the Orifice, it stuck so firmly to it, that, tho' the Weight of it was 20 Ounces, it would be raised a considerable Height, and tho' but a small Part of its Superficies adhered to the circular Edges of the Glass. The Reason of which seems to be no other, than that the Pressure of the external Air overpowers the weak Resistance made by the Air in the Bottle; and since the Resistance of the internal Air is so weak, the whole Orifice of the Bottle seems in some Measure to be a common Superficies; for as much as the Pressure of the Air in the Bottle, scarce makes any sensible Impulse upon that Part of the Book encircled by the Edges of it. The Solidity of Glass depends on a Juxta-position of Paris. And it is not altogether improbable, but that the compact Texture of Glass, may depend on a like Juxta-position of Parts, since the Particles of Fire, in the making of it, may so divide the Parts of the Ingredients as to render them subtle enough for so strict and close a Union, as is requisite to exclude Air from betwixt them; for it is not only obvious, That Air cannot penetrate the Pores of it, when heated in Distillation, but in blowing of Glasses where it hath not the least Vent; through the Pores of it, tho' impelled with Force, yet its Pores are fine enough to give way to the Beams of Light and Heat, and likewise to the fine Effluvia of a Loadstone, without damaging the Texture of it in the least; nor would it be more absurd to conceive that the Parts of Salt-petre or Ice were after the like manner joined together, by a Juxta-position. But to return to the Place from whence we have made this short Digression; tho' from hence it appears, that the Spring of the Air may contribute to the Cohesion of the Parts of Solids; yet it is not altogether necessary, since the same may be accounted for by the Air considered barely as a Weight; for the Air being a fluid Body, and pressing by its Gravity towards the Centre, it must needs diffuse itself every way, when resisted by the Surface of the Earth, and consequently expand itself orbicularly, by which means the whole Pillar of Air incumbent on it, being virtually incumbent on the lower Superficies of the Glass, whatever separates one from the other, must outbalance that Pressure of the Air; otherwise (there being no Air betwixt the two Glasses) they must needs stick together; but it is not necessary that the contiguous Superficies of these two Glasses should be equal to the Horizon, since if they be perpendicular, the Sides of the Glasses have a collateral Pressure from the Pillars of Air pressing against them, and consequently the Difficulty must be as great to separate them. But to try more exactly, How much the Pressure of the Air is concerned in the former Experiments, we took two polished Marbles, as smooth as we could get, and fastened Wires to the uppermost, so that the lowest could not slide off the other Horizontally, but, if any way, must fall Perpendicularly; which Caution being observed, we found, the one would not only draw up the other, but a Pair of Scales fixed to it with 16 Ounces of Troy Weight; and to make the Experiment more complete we found, That when the Surfaces of the Stones were wet with pure Spirit of Wine, the Air being by that Means kept from insinuating itself betwixt the Stones, the uppermost would not only draw up the other with a pair of Scales, but an hundred, and sometimes a hundred and thirty Ounces of Troy Weight; tho' the Diameter of the Stones exceeded not an Inch and two Thirds: But having repeated the Experiment with Oil of sweet Almonds instead of Spirit of Wine, we found, that it took up above four hundred Ounces Troy Weight: And that it may not be suspected, That this Difference proceeds from the more clammy Parts of the Oil, which caused the Stones to adhere more closely, I shall add, That the contiguous Surfaces being held perpendicular, tho' they would easily slide off each other, when moistened with Oil, yet would they not slip down, when moistened with Spirit of Wine, without an additional Weight joined to one of them, the Protuberances of one, perhaps, being fastened in the Pores of the other. But to show, That the Adhesion of these polished Marbles is proportionably greater as the Diameter of them is larger, and consequently as they are pressed together by a larger Pillar of Air, I repeated the same Experiment with Spirit of Wine, and took up about four hundred and seventy Ounces; but when I made use of Oil of Almonds, the Weight raised, was much more considerable, being a Thousand three hundred and forty four Ounces of Troy Weight; besides at the same time the Marbles were observed to stick close together: And here again, lest it should be suspected, that the Oil made the Adhesion more close, I shall relate this Observation, viz. That tho' it required so great a Weight to separate these Stones when their contiguous Surfaces were in an Horizontal Line; yet would they easily slide one upon another, not unlike the contiguous Glasses before mentioned; and for the same Reasons; and if they were the least inclined either this way or that, their own Weight was sufficient to separate them: From whence it appears how much the Air may be concerned in compressing the Particles of solid Bodies together. And lest it should be further objected, That the Cohesion of these Stones rather proceeds from Nature's Abhorrency of a Vacuum, than the Cause assigned by us, I shall add these Considerations; First, That if it were so, the same Reason would hold when a much more considerable Weight is fastened to the lower Marble; yet we see, that then, notwithstanding Nature's Abhorrency of a Vacuum, they presently part. Secondly, That the Pressure of the Air is sufficient to account for it: Which to make it more plausible I shall add, that tho' the Stone were fastened to the Ground, yet it would require as much Force, to separate the Uppermost from it in a Perpendicular Line, as to lift up a weight aequiponderant with the Stone, and the Pillar of Air incumbent on it, since there is neither Air, nor any other Body, betwixt the two Stones to help to raise the Lower up, and in part to sustain the weight of the incumbent Atmosphaere; and therefore it needs not seem strange, that when the lower Marble and the weight affixed to it, is not sufficient to balance the weight of the Atmosphaere, it should rise along with the Uppermost when drawn up, rather than be separated from it; since it is usual, for two Bodies, when joined together, to move the same way, if they be not separated by Weights or some other Force; which is observable in trying of Loadstones; for if the Loadstone be able to raise a Body more ponderous than itself, the Knife will as soon raise the Loadstone as the Loadstone will lift up the Knife. To Illustrate what hath been said I shall add an Experiment registered amongst my Adversaria, which is this, viz. Having immerged a Glass Syphon with a Brass Valve cemented on one end, almost half a Yard in a tall Cucurbite, till it touched the Bottom, I filled it with Water, till the Superficies of the Water in it, was equal to that in the Cucurbite, which being done, I took a pair of Scales, putting an Ounce weight into one Scale, and fixing a String to the other, one end of the String being likewise fastened to the Valve, fixed to the bottom of the Glass Tube; where it was to be observed, that by that single Ounce I was able to open the Valve, whereas when the Water was poured out of the Pipe, and it was immersed again, the Valve would not be opened again without the Additional weight of four Ounces; And in this Experiment it was further to be observed, that as the Valve was raised higher and higher in the Cucurbite, a weight portionably less was sufficient to open it. In which Experiment, if fuga Vacui resisted the opening of the Valve, it would have required the same weight at the top of the Water as in the Bottom, the Valve being in both places under Water. And therefore the difference rather proceeds from the Compressure of the Ambient Water, that presses the Parts of the Valve together. And tho' Air be a Body much more light than Water, yet considering that the difference is but about as much as 1000 to 1, and that the Particles of Air, which press upon our Atmosphaere, are incumbent upon each other for several score Miles in height; it is not absurd to expect, that their pressure should be considerable, and sufficient to press the two Marbles together. For a further Confirmation of our Doctrine of Firmness, to this I shall add another Experiment, which is, that having suspended the aforementioned coherent Marbles in a large Glass, when the Air was considerably exhausted the lower presently fell from it; And tho' the uppermost was let down to it, yet it could not be raised, till fresh Air was admitted into the Glass again, and then they were again pressed strongly together and became coherent as in the open Air. Rest itself for the most part sufficient to cause Rest. But to return to our Discourse from which these Experiments have made a Digression; tho' the Pressure of the Air may so join Bodies together, as to make them coherent; yet generally, Rest itself is sufficient to render a substance Solid; for since from what we have said above, concerning Fluidity, it appears, that it depends on the Motion of Minute Parts one amongst another; to deprive Matter of that Motion is enough to render it Solid, the Parts of a Solid being contiguous and at rest. The Opinions of some Ancients and Moderns briefly refuted. I know it is by all Philosphers, whether Modern or Ancient, usually held, that there is something else requisite to keep the Parts of a stable Body together: For some hold, that a Substantial Form is requisite; but since it is equally as difficult to conceive, how Matter should be so variously united in several Substances, by a substantial Form as without it, we may as well fly to imaginary Substances which are united by their peculiar Texture. Others think, that the Particles of solid Bodies are linked together by a Spirit diffused throughout the World, or by a certain sort of Glue, which Glews their small Corpuscles together. But as to the first it's altogether unlikely; for it may as well be a Question how those Parts stick to the Spirit, as how they stick to one another themselves; and it will be no less difficult to conceive, how the Particles of that Spirit itself come to be fastened together. Besides, were that true, it would follow, that Ice, which is looked upon as a Body void of Spirit, must abound with it; since the Parts of that brittle Substance, could not be joined by a Spirit which was not betwixt them: Nor is it more Reasonable to suppose them joined by a Cement, since it might likewise be asked, how the Parts of that Cement were linked together, which should it be affirmed to be done by a Substance yet finer, the Question might still be continued ad Infinitum; so that, it would at last be allowed, that some Parts of Matter must adhere without a Cement, or there must be Cements finer one than another ad Infinitum; which since it cannot be allowed, we may as well suppose, that the Parts of a Body adhere without a gross Cement, as that the Parts of a subtle Cement can stick together without another Substance to Cement them; especially, since the Corpuscles of a Body may be so figured and contrived as to be linked amongst one another very firmly; an agreeable Contact, with a real rest of Parts, contributing to render the united substances a Solid Body. But in favour of the former Opinion, it is urged by some, that the Spirit which they suppose joins the Parts of a Body together, consists of Parts indivisible; and consequently, there is no need of another substance to Unite them: But since Bodies as Solid and Adamantine as these can be supposed to be may be broke, a bare Affirmation must not be taken for Proof; for to suppose, that these Parts of Matter were made up of hooked Parts; it would be as reasonable to believe, that those hooked Parts might not be broke, as that by a violent Agent the Particles of the most Solid Bodies cannot be divided, since it is plain they may. But to proceed, The last thing we supposed necessary to constitute a Body, was the Texture of its Parts; and indeed tho' a Juxta-position and Rest of the Parts of a Body, are sufficient to render it Solid; yet if those Parts are more intimately interwoven with one another, so as to be linked together like Hooks, it must contribute to render the Body much more firm, Parts so joined, being much more difficultly separated, and put into Motion, than those which have only an immediate Contact; And it may not a little serve to confirm our Opinion, to take Notice, that in an Egg or Water, by a mere alteration of Texture, the Disposition of Corpuscles of those Substances are considerably changed; as when an Egg is, by the insinuation of the Parts of Fire, so altered, as to become hard; or as when the Latter as well as Water is beaten into a Froth, which in some Measure is like a Solid Body, as long as they continue in that Form. Having thus far inquired into the conjunct Causes of Solidity, we shall consider briefly, how many Ways a Body may come to be so Modified, and what things are requisite to make Bodies apt to put on such a Form. The Figure of the Parts of a Body contribute to their Solidity. The first and most remarkable thing is the Figure and Shape of the Parts of Matter, as if they be hooked or otherwise shaped, so as to entangle one within another, they will be with more difficulty separated; which is evident in close-set Hedges, where by pulling away one Bough the slender Twigs of others interwoven with it, make it harder to be separated; and not without pulling some others along with it; ●o likewise the slender Threads, which make up Cables, being twisted and wound one within another, are capable of sustaining a much greater Weight, and require much more Force, to braeke them. And indeed this Configuration of Parts seems to have been the Opinion of the ancient Atomists, of which Lucretius hath given the following Account in these Verses; Denique quae nobis durata ac spissa videntur, Haec magis hamatis inter se esse necess' est, Et quasi ramosis alta compacta teneri. In quo jam genere imprimis adamantina Saxa; Prima acie costant, ictus contemnere sueta Et validi salices, ac duri robora ferri, Aeraque quae Claustris restantia vociferantur. And indeed the correspondent Figures of Bodies may be so numerous, that the same Particles, which before in two distinct Bodies were Liquid, may, by an Union, have their Parts so interwoven with one another, as to become Solid; an Instance of which hath been given in the foregoing Chapter concerning Salt-Petre, where by a Mixture of a Liquor distilled from Nitre, with a Mixture of fixed Nitre run per Deliquium, a third Substance will be obtained firm and brittle, viz. a Saline Body. To this I shall add another, mentioned with a different design by Lul and Hartman, which is the following, viz. If two Parts of rectified Spirit of Wine; be mixed with one of Spirit of Urine tightly Dephlegmed, they will in a Minute unite into a consistent Body; but in this Experiment it is to be Noted, that the Spirits must be more rectified than those usually made use of by the generality of Chemists; and I shall further observe, that having myself had the Curiosity to try it, I found that Spirit of Hartshorn well rectified would have the same Effects, if made use of instead of Spirit of fermented Urine. And it may be fit yet further to observe that tho' there was such a predisposition in the Parts of fermented Urine to Coagulate with Spirit of Wine, yet the highest Spirit of unfermented Urine being of a different Texture would not Coagulate as the former. And it is further to be noted, that if this white Coagulum was kept in a Glass well stopped for some Months, by the means of Heat it would be Melted into a limpid Liquor; those Parts of the Liquor which were entangled one within another being broke and dissolved, so that the Particles of the united Liquors being again restored to such Figures as would enable them to move upon one another's Surfaces, the Coagulum assumed the Form of a Fluid Body. To this I shall subjoin two Experiments which seem to have an Affinity with the former; the first is, That rectified Spirit of Wine, by being digested with Saccharum Saturni prepared with Spirit of Vinegar, so far changed its consistency as to remain in a Glass without floating as a Liquid when the Glass was inclined; the Second is, That by the Addition of a dry Body, from whence nothing could be obtained by the help of the Fire, to the Coagulum just now mentioned, the result of this Mixture was a permanent Liquor. But for as much as the forementioned Experiment which produced the Coagulum upon the Mixture of Spirit of Wine and Urine is difficult to be performed, since it is a hard Matter to obtain Spirits fine enough for such a purpose, I shall subjoin a more easy one, which is, That if Spirit of Salt be added to the White of an Egg beaten to a certain Thinness, the Mixture will be so much Coagulated as not to afford the least Drop, tho' the Glass in which the Experiment is tried, be turned with the Mouth downwards for a considerable time. And Sir Francis Bacon relates an Experiment much to the same purpose; which is, That if the White of an Egg be shaken with Spirit of Wine it presently turn into such a Coagulum as will not yield one Fluid Drop in a Minute's time, and tho' that great Naturalist attributes the Effect of this Mixture, to the Heat of the Spirituous Parts; yet I rather think it the Effect of the particular Texture of its Saline Parts, since other Salts which are accounted cool, have the same Effect; And not only so but tho' Spirit of Wine will Coagulate the Whites of Eggs, yet it hath not that Effect upon the Serum of Man's Blood, tho' the Heat of the Fire will Coagulate the one as well as the other. But it does not only experimentally appear, that a consistent Body may result from a Mixture of two Fluids, but also that a Fluid may undergo such an Alteration as to be changed into two Consistent Bodies; and this is evident in distilled Salad Oil, since the Substance drawn over is devoid of Fluidity as well as that which remains behind; and to make it appear, that the Reason of it is the bare result of Texture and the hooked Figures of its Parts, if we add to the Oil a sufficient Quantity of Common Salt, it affords an Oil, which falls in drops into the Receiver, and retains its Fluidity. And to this it may be added, That by adding two pound of Brandy, and one of Sea-Salt to eight Ounces of Oil of Amber, the Texture of that Oil was so far from being so changed, as to come over clear and transparent; as Essential Oils drawn off in Limbecks, usually do. To which we may likewise add, That the Texture of Oil of Aniseeds, distilled in a Limbeck and Refrigeratory, with a sufficient Quantity of Water; will, by the Winter's Cold, be coagulated into a white brittle Substance, tho' it continues Fluid all the Summer. The Texture of Bodies contributes to their Fluidity, or Firmness. And to make it further appear, how much the Alteration of Texture contributes to the Fluidity, or Firmness of Bodies; and to what weak, and almost inconsiderable Agents, those Effects may be attributed; I shall subjoin another Experiment, which shows, that the Particles of a Body may be sufficiently agitated, to render it Fluid, by another not sensibly hot; for having melted coagulated Oil of Aniseeds by the Fire, and put it into two Glasses; the one was congulated again in a short time; yet the other continued dissolved, being only covered over with a Menstruum, in whose Parts there is no sensible Heat. To this I shall add another, of a much like Nature, which is the following. Having powdered some of that brittle Gum or Colophony, which remains upon the Evaporation of about a fourth Part of Venice Turpentine, I mixed so much of it with Spirit of Wine, that, the Liquor being wholly impregnated with it, some part might remain undissolved; which nevertheless had its Parts put into an Agitation, sufficient to render it, in some measure, a Fluid, tho' a Viscous Substance, notwithstanding the Force of the Menstruum was spent upon what had been dissolved; but tho' this Substance was kept in a Fluid Form in the Menstruum; yet in the Air, it would harden in a little time. And in this Experiment, it is likewise observable, That though, by a violent Agitation, the Viscid Matter was mixed with the Menstruum, yet it presently separated, and subsided again. The Textures of Liquots contribute to their Mixture. And this suggests to my Memory an Experiment, which shows how much the Textures of Liquors contribute to their Mixtures with each other; for tho' it be usually in General asserted by the Chemists, That Salts and Oils will not mix together; yet I obtained an Opacous Liquor, like Balsam in Consistence, from a Mixture of an equal weight of Oil of Turpentine, and Oil of Vitriol: And that it might more evidently appear, that the Mixture of these two Fluids, depends on the peculiar Texture of each, I committed the Mixture to Distillation; and obtained a gross Substance, which seemed to be that which united the other Liquors: For as soon as this was drawn off, the Liquors presently succeeded, but separate one from another, being not to beunited again, by a Violent Agitation, but so as to separate again, and swim one upon another. To this may be added the Liquor, which we have mentioned in another place, obtained by Distillation from Benzoin: One Part of it always continuing in the Form of an Oil; and the other, according to the Difference of the Wether, either shooting into clear Crystals, or preserving its Fluid and Oily Form. To which may be subjoined what we have formely taken Notice of concerning Salt-Petre; which, tho' when mixed with Water, it becomes Fluid; yet, upon an Evaporation of some Part of that, it presently shoots in Solid Crystals: From whence it not only appears, what a gentle Agitation of Parts is sufficient to keep a Body Fluid; but from hence we may observe, That sometimes Solid Bodies result from a Mixture of Liquids': So Oil of Vitriol, distilled with Quicksilver, leaves a white Calx behind it; and if we consider how Mercurius Dulcis is prepared, we shall find, that that Solid Substance consists for the most part of Quicksilver, the Salts united with it being scarce one Part of three of the Composition. And tho' Fluidity be opposite to Solidity, yet may it conduce to the Production of a Solid Body, since those Particles which lie in the Form of a Powder, and are not in a capacity to unite, may, by swimming in a Fluid, have the Opportunity of frequent Occursions, so that their Motion bringing them often together, they may, in time, be disposed to unite into one Body; which is evident in Powder of Alabaster; which, if when it hath been boiled for a considerable time, it be well burnt, and reduced to the Consistence of a thin Pap, with clear Water, will become firm, and admit of, as well as retain, any Form impressed upon it, by the Internal Surface of whatever Mould it is cast in: Where, that the Parts of the Alabaster are put into Motion, and variously agitated in the Water, is evident, from that sensible Heat, which for some time, succeeds the Affusion of Water; and this hath been sufficiently experienced, by filling a Glass full of this Mixture, which some time after it was stopped, broke the Viol, and hardened into a Substance, correspondent in shape to the Cavity of it; several Spoons-full of this Liquor it was moistened with, being squeezed out at a Crack, which was made by the Swelling of the Powder; and this Substance acquires such a Degree of Firmness, as to endure several strokes with a strong piece of Iron, without breaking. But there are several other Substances, which may acquire a greater degree of Solidity, than the Powder of Alabaster burnt; for the Learned Hydrographer Furnier, Hydrograph. lib. 2. cap. 6. relates a Story of a sort of Sand in the Kingdom of Naples, near Cuma and Puteoli, two parts of, which mixed with a third of Quicklime, becomes a hard Substance like Flint, when it hath lain or some time in the Water: To which Relation he subjoins, That the Lime-ashes of a certain Marble, near Tournay in Holland, being cast into Water, upon a heap of Stones, petrifies to that degree, as to change into a Substance as hard as Marble. But to return to what we have digressed from, That the Variously determined Motions of the Parts of Matter, contributes to their Union and Coalitions, into Solid Substances, appears from those Curious Salts, which Spontaneously shoot and Crystallize in the Bottom of Spirit of Hartshorn, when it hath been exposed to the Air for several Months: For those Particles, by frequent Occursions, are by degrees so disposed to unite, that at the length those Parts, which are most apt to cohere, meeting together, they form tightly figured Crystals, which adhere to the sides of the Vessel. And it is not less Remarkable, That tho' a Tincture of Amber, drawn with pure Spirit of Wine, for some Years continued Fluid; yet, at the last, some of its Parts were so combined, as to form little Parcels of Amber, almost Spherical in Shape, which adhered partly to the Sides, and partly to the Bottom of the Vessel. Solidity may proceed from the Interposition of the Minute Parts of another Body. But there are yet other ways, by which Bodies may become Compact and Solid, as first by the Insinuation of Small Particles of Matter, into their Pores and Recesses; which may produce their Effects various ways: First, by driving out those Particles, which being disposed to Motion, hindered the Cohesion of the Fluid Parts. Secondly, by obstructing the Motion of the Fluid Parts: And, Thirdly, by altering the Constituent Parts of the Fluid, so as to render them unapt for Motion, and inclinable to a mutual cohesion: So the Particles which constitute Rennet, by Uniting with some Parts of the Milk they are mixed with, link them together, and cause them to unite into a Coagulum; and that the Parts of the Rennet cause them to coagulate; and that they unite those Viscid Parts, and link them together, is plain; since it is a usual Complaint that the Cheese made where Rennet is used, tastes very strong of it. And that the Coagulating Virtue depends on the Saline Parts of the Rennet, appears; since other Acid. Liquors have the like Effect in Coagulating Milk, as Juice of Limmons, etc. as also a very small Quantity of Oil of Vitriol, artificially mixed with it. To which I shall add, That some Years past, I prepared a certain Salt, endued with Qualities not unlike those ascribed to Glauber's Sal Mirabilis; which would not only, like other Salts, when dissolved in Water, upon Evaporation, shoot into Crystals, itself; but also would coagulate, and Crystallize a triple Quantity of Water with them, which would so far put on the Nature of a Salt, as to become brittle, and to be reducible to Powder. A Liquor turned into a Consistent Body, by the Addition of a Powder. And it may not be fruitless here to subjoin, That tho' the Particles of Oil of Vitriol, be in so violent an Agitation, as to acquire a Sensible Heat, upon their Mixture with some Bodies; yet I so altered the Texture of that Liquor, as, by a Mixture of a certain whitish Powder of my own Preparation, to render it a Consistent Body: In which Experiment, it was observable, That several Days, after the Oil was coagulated, the Powder remained undissolved in the Bottom of the Viol; so that the Coagulation seemed to be effected by some subtle Effluvia, insinuating themselves into the Pores of the Liquor. To this Experiment, I shall subjoin another, in which the same Effect was produced, by leaving Oil of Vitriol upon Crystals of Salt-Petre well dried; where it was to be noted, That the Oil was not only Coagulated, but seemed to be joined together, by certain Fibres, which were formed out of the Saline Effluvia of the Salt-Petre, dispersed through the Body of the Oil. And that those subtle Effluvia, which insinuate themselves into the Pores of a Fluid Body, may so alter the Texture, as to render it Solid, is more eminently evident, from the Fumes of Lead, which Coagulate and harden, Quicksilver; and that Led, does really emit such Fumes, is evident, from the Effects which a Physician] observed in himself; viz. both Vomiting and Purging, by barely holding his Head over melted Lead, several times successively. and it hath been observed by the Famous Geometrician Dr. Wallis, That the Fumes of Lead, have, by being several times melted, been so spent, that the Led, after the first time it was melted, sometimes lost its a Coagulating Virtue. And Phaenomena not much different from the former, are exhibited by the following Experiment: For if either Common, A Fluid turned Solid. or Oil of Sweet Almonds, be poured upon Aqua fortis, the Steams of the Latter will soon Coagulate either of them; whereas if Camphire, which is a brittle Substance, were cast upon the same Aqua fortis, it would be turned into an Oily Substance; A Solid Body turned Fluid. which shows how much the Effluvia of Bodies may contribute to Fluidity, or Firmness, accordingly as the Bodies acted on, are pre-disposed to assume different Forms: And before I leave this Experiment, it may be material to take Notice, That tho' Oil of Tartar, per Deliquium, be endued with an Extraordinary Faculty of Mortifying Acids, yet it would not reduce the Coagulated Oil to a Fluid Form. But to proceed: The Last way by which such Penetrating Effluvia may conduce to the Solidity of Bodies, is, by putting those Bodies into such Violent Motions, as they may, by being impelled upon, and knocked one against another, be disposed to Union, and to be entagled one within another. And tho' this Concurrent Cause, never acts separately, without the Joynt-Action of the aforementioned Ways, yet is it necessary to make a Distinction; because this differs from the Former, in as much as these Effluvia, contrary to the other, make up no part of the Body, upon which the Alteration is wrought, but only agitate the Parts of it: So that the Figure and the Texture of the Parts of the Body, become different from one another, A Complication of Parts sufficient to render a Body Solid. and more complicated. And that a bare Complication of Particles, is sufficient, in a great Measure, to render a Body stable, will appear from an Observation very common; viz. That That tho' from a heap of Osiar-wands, a single Twig may be taken, without removing the rest; yet if they be twisted together in the Form of a Basket, the whole follow upon the taking up of one; and the same may be observed, in most of the Works of Mechanics. And what great Effects bare Motion may have, in altering the Textures of Bodies, is manifest, and very obvious in Churning; where the Branched Particles, which are dispersed and diffused through the whole, by frequent Occursions, are so freed from the rest of the Liquor, that they presently unite, and form that soft Oily Substance called Butter; and not only so Homogeneous a Body as Milk, may be so altered by Motion, but even Oil of Turpentine, may be rendered a Consistent Body, without the Assistance of any other Agent, than Motion given to its Parts by Distillation, the Substance drawn off being a Stable and Consistent Coagulum. And to illustrate farther, what we have delivered of Fluidity and Firmness; I shall add the following Experiment; viz. That Oil of Wax, being distilled, afforded a Substance not unlike Butter; which when it had stood a while, was dissolved, without the Influence of any External Heat, into a Transparent Oil. A Change of Qualities succeed a Change of Texture. But further: Fluidity and Firmness so much depend upon Texture, that the same Corpuscles, which united one way form a Fluid, by an opposite Texture, may become Solid, and è conversò: And this is not only evident, in Water successively Froze and Thawed again; but also in Metals, which, after Fusion, put on their Pristine Form, upon Cooling: But a more Emiminent Instance is, That Quicksilver being kept in a Sand-Furnace, for about ten Weeks, in a Glass-Vessel well stopped; the Particles of that Body, being variously entangled and wound together, constitute a Red Powder; which may, by Chemists, be precipitated per se; and in a few Hours, if a quantity of Quicksilver be distilled in a Glass Retort, a Red Powder, like the former, will remain in the Bottom, as well as about the Sides of the Vessel: In which wonderful Phaenomenon, it is not absurd to imagine, that the Change is wrought, much after the same manner as in Whites of Eggs, which by an Alteraration of Textures, become hard; or, that by frequent Revolutions, the Parts of that Liquor are so linked one within another, as to put on a different Form; and whatever may be the Method by which this Change is effected, yet, that it depends on an Alteration of Texture, is most certain; since that Powder being raised in the Form of Fumes, in a convenient Glass, condensed into Running Mercury, in the Neck of it. But to prove further how much Motion, or Rest, contributes to the Fluidity or Solidity of Bodies, I shall add, That I once had Mercury, which I looked upon to be Mercury of Saturn, which by being barely agitated to and fro, would put on the Form of a Black Powder, which would again become fluid Mercury, by grinding it in a Glass-Mortar. Fluids' consist not of Parts divisible into Fluids, as Quantity into Quantity. From which Experiments of Mercury, we may learn, what may be thought concerning the Opinions of some Modern Philosophers, who are of Opinion, That Fluid Bodies may be divided into Fluid Bodies, as Quantity into Quantity; as if every Particle of a Fluid Body, must be Fluid itself; since, from the aforementioned Experiments, it is evident, that the Particles which constitute Fluids, are Solid in themselves; forasmuch as, upon a bare Change of Texture, they appear in that Form; which is rendered further probable, if not evident, both since the Particles of which Salt consists, being dissolved in Water, put on, as to Sense, the Forms of Fluids; as well as, because the Corpuscles of so Solid a Body as Silver, do the same, when dissolved in Aqua fortis: And on the contrary, the Calx, remaining behind, after a Distillation of Quicksilver, with four times its quantity of Oil of Vitriol, in a Sand-Furnace, is a Consistent Substance, which, if dissolved in Water, will after Evaportion, shoot into very brittle Crystals; which rather proceeds from the Parts of the Oil condensed, than from those of the Metal; since the Calx remaining behind, exceeded the weight of the Mercury, the Liquor drawn off, being not equal to that of the Oil. And I am further confirmed in this Opinion, because I have observed several Crystals sometimes to adhere to the Sides of a Glass, in which Oil of Vitriol was contained, which were again resolved when exposed to the open Air into the pristine Form of Oil. But it may be further urged, as an Argument against the Divisibility of fluid Bodies into such fluid Parts, that if it were so, all Bodies would be equally disposed to insinuate themselves into the Pores of other Bodies; and it would not happen, that one Body should be more inclined than another. Motion as well as Minuteness of Parts requisite to Fluidity. It is not indeed to be denied, but that a fluid Body may be divided into very small Parts, considered barely as Matter; and that Minuteness of Parts may render it more apt for Motion, and consequently more fluid; but it does not therefore follow, That the Parts of a fluid Body are indefinitely so divided, because considered as Matter, they may be Mentally, since it does not appear, that they are Naturally so divided: Besides, to render a Body fluid, Motion as well as Minuteness of Parts is requisite, which appears from what we have said before concerning Powder of Alabaster, which puts on the Form of a fluid, by having its Parts violently agitated. But Solidity not altogether proceeding from Saline Parts. From what hath been already premised it appears likewise, What Thoughts we are to entertain of the Doctrine of the Chemists, who assert, That Coagulation, Stability, etc. are the Effects of saline Parts. For tho' Salt hath a Power to curdle Milk and coagulate other Humours; yet the hardening Properties of it are not the Effects of any inexplicable Qualities inherent in it; but of the Shape and Motion of the Particles which constitute it, which, by insinuating themselves into the Pores of a Body, and sticking several Parts together, do like a Wire fasten them one to another. But notwithstanding the saline Parts of a Body may thus contribute to the Solidity of it, yet it is not an Ingredient altogether necessary; since the Parts of a Body may be so interwoven, and, by reason of their Figure and Contexture, be so disposed to Union, as to form a solid Body without the Association of a saline Ingredient; besides, it might be urged, That Salts themselves may easily be reduced into fluid Substances, by a Mixture of Water; and several of them, as Salt of Tartar, etc. will, without the Addition of any other Body, barely by being exposed to the Air, be rendered fluid. But not to insist upon these Instances, I shall rather desire to know, what Salt can be supposed to insinuate itself into, and cause Solidity in Mercury, when it coagulates in the Fumes of Lead? Or what Access of saline Parts can be imagined in the Preparation of Mercury precipitated per se? And it may as well be questioned, how any saline Body can penetrate the fine and subtle Pores of Glass? When, in a cold Night the Water contained in it is frozen, and is turned to so consistent a Substance as Ice. And it may be likewise noted, That tho' the Shells of Hen's Eggs be soft when first laid, yet they presently harden without the Addition of any other saline Ingredient. And that this Effect cannot be wholly attributed to the Influence of the Air, it may be urged, that it hath oftentimes been observed, That Shells have been found hard several times in the very Bodies of the Hens, before they were laid. But that which I look upon to be a more convincing Argument, is, that in Egypt, where Eggs are hatched by the Influence of a moderate external Heat, that fluid Substance is changed into several Parts, of very different Degrees of Consistency, without the Addition of any other Body, or the Accession of a new Salt. But further, I shall make use of Arguments drawn from the Concessions of the most Eminent of their own Writers; for in transmuting of Quicksilver into Gold, by a white or red Tincture, the Quantity of it being only a Grain to a Pound of Quicksilver; it may justly be demanded, How so small a Quantity should change six or seven Thousand times its Weight, whereas even that Grain is not altogether saline, Part of it being a▪ sulphureous Substance? And it is observed, that Helmont affirms upon his own, as well as the Experience of Raymond Lul, that if the Alkahost were drawn from Quicksilver, the fluid Mercury would be so coagulated, as to be capable of being reduced into a Powder, tho' not the least of the saline Liquor was left behind. And I am credibly informed that the present Duke of Holstein hath by him a certain Glass Spirit of Urine, which in cold Wether shoots into Crystals, and in warm dissolves into a limpid Liquor, which Spirit was not otherwise prepared than by cohobating the distilled Spirit so often, till the whole saline urinous Substance was brought over united together into one Mass. And for a further Confirmation of the Doctrine by us delivered, to these I shall add, that it hath been observed, that if so much as Juice of Lemmons falls into a Cauldron of Sacharine Syrup, it keeps the whole Mass from Thickening into a Sugar; and this is confirmed, both by the French Publisher of the Natural and Moral History of the American Islands, called Les Isles Antilles Histor. Moral. Cap. 5. and also by Gulielmus Piso Histor. Nat. & Med. Brasil. l. 4. c. 1. the latter of which expresses himself in these Words, Si Momentum succi Limonis, vel Acidi quid injiciatur, Sacchari Consistentiam nunquam acquiret, sed in totum perditur; and it may be further observed to our present Purpose, that in making of Sugar, the Juice squeezed out of the Canes, is usually first depurated in large Vessels of Copper, from whence it is removed into Vessels of a less Size, in order to a farther Depuration; where we are to note also, that whilst it remains in the larger Vessels, they usually add very strong Lees to promote Depuration, and when the depurated Liquor is removed to the small Vessels, it is the Custom to add Oil or Butter to preserve the Liquor, and to prevent it from boiling over, which Preparation Piso takes notice of, together with the abovementioned Author, the Words of the former being these, Observatu dignum, si Oleum majoribus inderetur Ahenis, in quibus Liquor primus, Caldo dictus, purificatur, Saccharo conficiendo planè foret ineptus; vicissim si minoribus lixivium sicut majoribus infundatur, aequè impossibile Saccharum conficere. The Fluidity and Firmness of Bodies depend so much upon the peculiar Texture of the Matter which constitutes them, rather than on a saline Substance. To these Authorities, for a further Confirmation of our Hypothesis, I shall add a few Experiments of my own; and first, having prepared a Liquor not much inferior in Saltness to Aqua fortis, and then put small Fragments of solid Hartshorn into it, we found, that they were gradually softened, the Particles of the Liquor insinuating themselves into the Pores of the consistent Body, and rendering it in a few days time of the Consistence of a Mucilage: We mixed likewise Spirit of Vinegar with Salt of Tartar, An insipid Water drawn from Sp. of Vinegar & Salt of Tartar. till the Ebullition wholly ceased, and by Distillation obtained an insipid Water from the Mixture; and so successively poured fresh Spirit of Vinegar upon the Mixture, and again extracted the insipid Water, repeating reiterated Affusions and Distillations, till the fixed Salt was sufficiently impregnated with the Acid Parts of the Vinegar; and then we obtained a Mixture, tho' made up of pure and elementary Salts, which so far emulated a fluid Body, as to depose its saline Form when influenced by a very moderate Heat. Camphire dissolved in Oil of Vitriol, etc. Again, we mixed some Pieces of Camphire with Oil of Vitriol, by which they were presently dissolved into an Oil, and when violently agitated together, readily mixed with the Oil of Vitriol, and seemed to constitute a uniform Liquor for several Hours; yet by an Addition of four times as much fair Water, the Camphire presently assumed its own Form again, and swum upon the Top of the Liquor; where it is to be noted, That the saline Parts of the Oil of Vitriol render the Camphire Fluid, instead of making it more Solid; and on the contrary, that Fluid is turned into a Consistent Body again, by a Body so much void of Saltness as Water. And that a Body may acquire those other Qualities, viz. Hardness and Brittleness, without an Addition of Saline Parts, is evident, from the different Tempers that may be given to a Piece of Steel; for if it be immerged in Water red hot, it acquires a Brittleness and Hardness, which it hath not, if leisurely cooled in the Air; yet if it be again heated till it turns to a deep Blue, it acquires a comparative softness and aptness to bend. And that an Alteration in Texture, is enough to render a Body more or less Solid, is evident in Snow; for its Parts being compressed more closely together, it is abler to resist the Impressions of other Bodies; and yet when further, by thawing it, its Parts are brought closer together, it hath a greater degree of Solidity and Firmness, when Froze again; the Texture being much more close and compact, than that of the Snow. But by some it is taught, that Induration depends on a certain inward Principle, A Plastic power inherent in Bedies. or a Plastic Power, called by some a Form and by others a Petrifying Spirit, lodged in a Liquid Vehicle. And indeed, since I have observed, that some Stones dug out of the Earth are endued with such curious and exquisite Figures, as if they had been the product of Art; I cannot but acknowledge a Plastic Power, which the wise Creator of Things hath implanted in certain Particles of Matter, which produce both the determinate Figure as well as consistnce of those Bodies: Plastic Power what? But we disagree with the generality of those Philosophers, as to the Manner in which this internal Principle produces its Effects; and since the Manner of it, by them, is not intelligibly explained, it will be necessary to Consider, how many ways Nature takes to render Bodies Solid, by which we shall be better Qualified to Judge of the Manner which those Particles operate by, in which the Plastic Power is said to lodge. But to proceed; For as much as Hardness is the highest degree of Firmness, we shall endeavour to make it appear, that an Alteration of Texture, concurring with other dispositions of the component Parts of a Body, is enough to render it hard without the Addition of an adventitious Salt. The Tradition is common amongst those, that search into the Secrets of Nature, that Coral, tho' a hard Substance with us, is a soft Body whilst remaining under Water, according to that of Ovid, Sic & Cor allum quo primum contigit Auras Tempore durescit, mollis fuit herba sub Vndis. Ovid. Metamorph. Lib. 15. And tho' Beguinus Tyrocyn. Chym. lib. 2 Cap. 10. hath urged very strong Arguments against this Tradition; yet, that it hath sometimes been found true, appears from what Gassendus lib. 4 An. Dom. 1624. relates of an Ingenious Gentleman, who Fished for Coral near Toulon, viz. The Plants, which were plucked up, and drawn out, were neither red nor handsome, till their Bark was pulled off; in some Parts they were soft, and would give way to the Hand, as towards the Tops, which being broken and squezed, they sent forth Milk like that of Figs. To which may be added the Testimony of the Jesuit Fournier, Hydrograph. lib. 4. Cap. 27. And I am informed by one that Practices Physic in the East-Indies, that he gathered white Coral divers times on the Sands of the Island Mehila (not far from that of Madagascar) which is usually as soft as an Onion; and is observed to decay, if it is not gathered at a certain Season of the Year. Agreeable to which Piso lib. 4. Cap. 68 making mention of several stony Trees on the Brasilian Coast; says, E fundo erutae mox durissimae; si insolentur in Littore, siccae niveique coloris fiunt, which may be favoured by the following Relation of Scaligers. Ex bovillis Oppidanus adjutus Medicamentis eminxit vitrum sane ex illa Nobili Paxagorae pituita dum mingeretur, albuminis mollity, emissum vitri duritie ac splendore, Senatoris filius ejecit, puttis modo multis, & maximos: Qui aeris Contactu, postea in Gypseam tum speciem tum firmitatem concrevere; hic quoque nunc recte valet. And I have been informed by a Merchant, and likewise a Chemist of Dantzick, that several Lumps of Amber have been taken up soft upon their Coast which presently grew hard in the Air; which I the rather believed, because I have several times observed, both Spiders, Flies and Straws enclosed in Amber. Observations of Indurated Bodies. And here we may take Notice, that tho' it from hence appears, that some Bodies which are soft under Water, become hard when exposed to the Air; yet it is a Matter of difficulty to determine, how much, the Infivence of the Air contributes to the hardening of them: For Gassendus in Vita Piereskii. lib. 1. says, he hath observed in the lesser Streams of the River Rhosne, where he usually washed himself, several Lumps of hard Substances, upon the same Place, where he was wont to find the ground smooth and soft; and that some time after, the same hard Substances remaining in the Water, as well as some which he carried home with him, were turned into perfect Pebbles; from which relations, and also what we have before observed concerning the Powder of Alabaster, it appears, how much the Mechanical Textures of Bodies, together with other Mechanical Qualities contribute to their various Forms; for besides the aforementioned Instances I have observed, that that bony Substánce, so much esteemed by Physicians, which is usually taken out of the Deer's Heart, and is of a hard Consistence, hath appeared, in one of those Creatures which I purposely looked into, to be soft and flexible like Cartilages. And indeed Solidity seems so much to depend upon Texture, that it may justly be doubted, whether the most solid Bodies have not before their Concretion been in Fluid Forms; since amongst other Rarities I have seen, in the midst of Stones, the exact Figures of Fishes with their Scales and Finns, etc. And I have known, not only Wood, but several other Substances as Lead-oar, Minera Antimonii, Marchasites, etc. found in the midst of stony Concretions; which are strong Arguments that those Stones have been before their Indurations in the Forms of Fluids; and from hence we may have ground to Question the Opinions of some, who think, that Stones and such like, or more solid Concretions, have been existent in the same Forms since the Creation; since we may with probability enough presume, that these Concretes are the Results of Matter, newly modified; and united after a different Manner from what they were before; otherwise it would be impossible, that such things should be lodged in such hard Concretes; And these Considerations and Observations may farther confirm, what we have elsewhere noted concerning the growth and increase of Minerals. But the most eminent Instances, to show, how much the Fluidity and Firmness of Bodies, A very remarkable Instance to show how much Fluidity, etc. depends on Texture. is owing to the Texture and various Coalitions of their Parts, are in those Waters, which when permitted to rest, instead of Fluidity acquire a stony hardness. And it hath been observed in some hollow Caves, that by the Coagulation of a certain Humour, which issued out of the top of it, several Concretes have been form like Icicles; of which I have some by me now, gathered by a very ingenious Person, which are of a perfect stony hardness, being 8 or 10 Inches in Length, and of a proportionable Thickness; and I have also now by me, certain stony Concretes sent me from a famous petrifying Cave in France. And if we will give Credit to Aventinus as well as some other Authors, he hath recorded, in his History, that several Men and Women were at once Petrified by a Terrene Spirit, and changed into Statues; that Petrifying exhalation operating much after the same Manner, and altering the Texture of their Bodies, as when by Incubation and the subtle Insinuations of calorifick Atoms, the Parts of an Egg are so newly modifyed and disposed, as to put on the Form of a Chick. And it is Testified by Pamphilio Pixcentino, of a Woman in Venice, who upon eating of an Apple, was turned into a very hard Stone, after she had been hideously tortured for about 24 hours; Mixture sufficient to produce Petrifaction. which History together with Observations of my own, which I shall add, will be a good Argument to prove, that even Mixture is sufficient to petrify some Bodies; the Observation is in the following Experiment, viz. If two Ounces of Quicksilver be mixed with two Ounces and a half of Verdigreese, together with about an Ounce of common Salt, and put into a Frying Pan; when that Mixture hath been Boiled for a considerable time, with an equal Quantity of Vinegar and Water, gradually infused, as it wastes by Effluviums, the Mixture, washed and cleansed from its Salts, will afford an Amalgama not unlike Quicksilver; which, if Dexterously prepared, may be cast into Moulds and form into embossed Images; and it is in this Amalgama very remarkable, that tho' at the first it is so soft, as in a great Measure to emulate a Fluid Body; yet when for some hours exposed to the Air, it becomes hard and as Brittle as Steel; where the Induration seems to result from the Coalitions of the mixed Ingredients, and their new Texture, rather than from any innate Principle; The Particles of the Fluid Mercury being so entangled and interwoven one with another, as to lose their former Fluidity, and to convene so closely as to unite into a Solid Body. And that the Induration depends on a Mutual Combination of the Saline Ingredients with the Mercury, is beyond doubt; since not only a true and perfect Copper may be obtained from the Amalgama; but when it hath been for some time exposed to the Air, the Surface will be covered over with the Saline Parts of the Verdigreese, which have freed themselves from their more intimate commixture with the metalline Particles of the condensed Quicksilver. But lest it should be Questioned, whether the Particles of Salt can have any sensible Operation, when mixed with a Body so firm as condensed Quicksilver, I shall add, that in Bodies much more firm, it hath been observed, viz. in those Stones from which Vitriol is got; for it is remarkable in them, that when they have been for some time exposed to the open Air, the internal Agitation of the Saline Parts, is so violent, that several of them will not only swell, but even burst asunder. And I remember that having preserved a Mineral, much of the same Nature with these Stones, in my Chamber, the Superficies was covered with a Powder, both in Colour and Taste resembling Vitriol. And that the Motion of the Parts of this Amalgama, whilst it was Fluid, which they might be put into, by the external force of the Fire, might contribute to their Concretion, we have sufficient Reasons to believe, from what is related and observed by experienced Masons, viz. That the best Mortar will not acquire it's utmost compactness, under 25 or 30 Years, and that, after a long time, it becomes so hard, as to be more unapt to break than the Stones it Cements. But lastly, that the Condensation of the Parts of the Quicksilver, depends on the Mixture of the Ingredients, and the Texture thence resulting, is evident; since the Proportion of the Ingredients being varied, the Condensation of the Mercury was neither so speedy, nor so firm. And that it may appear, That Nature and Art sometimes take Measures not unlike, in the Hardening of Bodies, I shall add a Passage from a Jesuit, named Pierre Belleprat, who relates it as an Observation in the American Continent, where he was sent to preach to the Indians: A Strange Sort of Earth. The Relation is, That near the Mouth of the River, there is to be found a Green sort of Clay, which being soft, and capable of being put into any Form, whilst under Water, grows so hard when exposed to the Air, as not to be much softer than Diamonds; and this, he says, the Natives usually make Hatchets of, which they cut their Wood in pieces with. But, A Concrete resulting from a Mixture of Spirit of Wine. and a Solution of Coral. To conclude this Discourse, I shall add an Experiment, which will be a farther Confirmation, That Fluidity and Firmness, depend on Texture, and the Motion or Rest of the Insensible Parts of Matter. The Experiment is, That having made a Solution of Coral in Vinegar, so strong, that part of it fell to the Bottom; I poured Dephlegmed Spirit of Wine, upon the Clear Decantated Liquor, so gently, that it might swim upon it for some time; where it was suprizing, that upon a violent Agitation, the two Liquors being mixed together, united into a Concrete so firm, as not to afford the least Drop of a Fluid Liquor; yet by adding an equal quantity or thereabouts of Spirit of Nitre, it would again lay down that Viscidity, and become a Transparent Liquor. And here it will not be amiss to specify, That this Experiment is so difficult, that it scarce succeeds, without a great deal of Caution; for, First, If the Tincture be not strong enough, or the Spirit of Wine not rectified, the Coagulation will be but partial, and not so quick: Secondly, The Experiment hath succeeded in a Wide-mouthed Glass, where it had a free access of Air, tho' it would not in one which was closer: Thirdly, Upon an Infusion of Spirit of Nitre, the Mixture must be stirred with an Instrument, made of Gold, Wood, or Glass, lest the Menstruum corroding it, should render the Experiment unsuccessful: And Fourthly, The quantity of each of these Ingredients is hard to be defined, by Reason of the Difference in respect of the Strength of the Tincture, and the Spirituousness of the Spirit; but it is rather to be learned, by Varying the Proportions, if the first Trial does not succeed. Having made this Progress in the History of Fluidity, and Firmness; It might be seasonable to pass on, and consider those other Qualities relating to it; as Hardness, Brittleness, Softness, etc. but remembering the Advice given by some of the Ancients, Noscenda est Mensura sui; I shall leave them for others, who are better able and more at leisure; being content, that I have explained the two former Qualities more Intelligibly, than some of the Peripatetics, or Chemists; having laid open a Way to accommodate Chemical Experiments, to the Explanation of Fluidity and Firmness, so as to deduce those Qualities, from more Intelligible Principles, viz. Size, Shape, and Motion. CHAP. XIV. An Essay of the Intestine Motions of the Particles of Quiescent Solids. The Signification of the Word Rest limited. THE Word REST, is of so Ambiguous a Signification, that before the Question, Whether there be in Bodies any Absolute Rest? can be answered, it is requisite to consider, That in the Common Acceptation, it is used to denote, such a Rest as is not perceivable to Sense; but when taken in a more Strict and Philosophical Sense, it usually signifies such an Absolute Rest, as to intimate a total Negation of Motion. In which latter Sense, if it be taken, I will not affirm, That there is such a Rest, even in the Parts of Solids; since it is not improbable, but that there is Motion, tho' imperceivable by Sense, even in the most Solid Bodies. In favour of which Opinion, were it necessary, I should offer Arguments à priori, deduced from the Doctrine of the Epicurean and Cartesian Principles. For should we allow the World to arise from a Casual Concourse of Atoms, and that there were actual Motion in all of them; it would not be absurd to think, That tho' in Forming Concretes, they are usually wound one within another, yet there is a continual Endeavour to Elasticity, by which they continually strive to disentangle themselves, and to fly away, and consequently the Result of those Endeavours must be a Motion amongst those Atoms. And on the other side, should we, with Cartesius, allow a Continual Circulation of a Materia Subtilis through the Pores of Bodies, we may imagine, That the Insensible Atoms, which constitute that Body, will be shaked and disturbed by it, tho' not so much as to be perceived by Sense: So in the Summer, the Leaves are carried off the Trees with gentle Gales of Wind, which are not perceived by those that stand some Distance off. But not to enlarge upon this Point, it may appear, from several of the Phaenomena mentioned above in the History of Fluidity, that the Particles of Bodies may be in Motion, tho' that Motion is not discerned; and Particularly, that of Water; where tho' its Parts be in a very Various Motion, yet to Sense they seem to be as much at Rest, as those, which form the Glass, in which the Water is contained. And that there may be a like Motion, in the Substance of Silver or Iron, may be argued from what is evident to the Touch, or by throwing Water upon them when hot, it being peculiar Properties in them when hot, to burn the Fingers, and to set the Water a-boiling; and the like Qualities, tho' not so violent, may be raised without the help of Fire, by barely Hammering of Iron, or Silver; they not only, by that means, acquiring a Power to heat, but likewise to raise Water into Vapours. Argument to prove Motion in Solids. But if to this it should be objected, That tho' the Motion be indiscernible; yet the Agent that gives it that Motion is not, since we can discern how those Qualities are added to it, and how the Alteration is wrought: I answer, That tho' a Vigorous Loadstone, appears to be drawn along its Axis, and back again, the Alteration is not visible in the Body of the Iron; yet it certainly loses, after it hath acquired, those Noble Faculties, viz. it's Attracting and Directing Virtues properly belonging to Magnetical Bodies: But, that there may be in Metals a Motion, tho' not discernible, is further evident in a Bell; which a long time after it has been struck with the Clapper, continues to put the Air into an Undulating Motion; and thereby to cause very odd Sounds; which must be an Argument, that the Partieles of that Bell are in a very nimble Agitation; otherwise they could not communicate Motion to the Circumambient Air, and thereby cause such a Noise in the Ear. But I must confess there are two Difficulties, Objections answered. which occur to what I have been offering: As First, That it is hard to imagine, how the Internal Parts of such Solid Bodies should be worked upon, by Agents so weak as the Air, and especially some parts of Matter more Minute, which are dispersed through it: And Secondly, It may be questioned how any Parts of Matter can be moved so slow, if at all, as to be so long in moving from the Internal Parts of a Needle, to the Superficies, as our Hypothesis requires: But, To the First, I answer, That those External Parts are not the sole Causes of these Motions, but only assistant to the Principal; which is evident from what hath lately been noted concerning the Connate Dispositions to Motion, attributed to Matter, according to the Epicurean and Cartesian Philosophy; and by the Effects of a Loadstone upon the Needle, we may be taught to guests, what lasting Changes may be produced, in the Textures of Bodies, by the Influence of very Insensible Parts of Matter. And as for the other Part of the Objection, viz. The Slowness of Motion, which Nature makes use of in some of her Works, are altogether as inconceivable, as the Motion of a Shadow upon a Dial, or of an Index upon a Clock: And Nature may upon other Accounts, and undoubtedly does, make use of Motion in a degree yet more remiss. But not to insist upon the Slowness of Motion, which Nature makes use of, it may be otherwise offered against this Objection, that the Motion of the Insensible Corpuscles of a Loadstone cannot be supposed to be in a Direct Line, since they must not only pass through Pores very crooked and intricate, but must also meet with several other Particles of Matter, which will oppose them; and not only drive them back, but also make their Passage still more intricate and winding, by driving them from one side to another, as well as several other ways, by which their Motion may be retarded. Besides it is but Reasonable to suppose, That it is much more easy to keep a heavy Body in Motion in its own Medium, than to remove it from that to another. But to decline Speculations, Instances alleged. I shall bring Instances to confirm what I am about to prove, viz. That the Corpuscles, which constitute Bodies, are inclinable to Motion, and that their Motion is very slow: The first Instance I shall mention, is in a Spring made of Steel, which, tho' it be pressed and squeezed together for some time, it will, upon a Cessation of that Pressure again, unbend itself, and recover its former Position; but if it be kept long in that compressed Posture, it will by degrees lose that Power of Restitution, and continue in its crooked and unbended Figure: From whence we may learn, That tho' Elastic Parts may be endued with an Endeavour to expand themselves, yet they may be a long while in working their Effect; since we see, that Steel being put into a Springy Form, retains that Springiness for a long time. The Effects of a Bar of Iron held in a Perpendicular Posture in a Mariners' Compass. But to confirm what I have been discoursing of, and to evince what considerable Changes the Air may Effect in the most Solid Bodies; I shall add this Observation, viz. That if one End of a Bar of Iron, held perpendicularly, be applied to the Point of a Mariner's Compass, it will force it away towards the East or West; but if the Position of that Bar be altered, it presently loses its Magnetical Qualities: Yet it is observed, That if this Iron Bar be kept long in a Window, it's Magnetic Qualities become much more durable and constant; from whence it appears, That the Air together with the Magnetical Effluvia of the Earth, may work changes very lasting upon the Particles of Solid Bodies, by insinuating themselves into their Pores; and that the Motion, which must needs be concerned in altering their Texture, must likewise be very slow, since it cannot in a little time acquire such Magnetical Virtues. But to proceed to a further Confirmation of what we have delivered, the first Observation I take Notice of is, that it is usnally observed, That if Lignum Vitae, which is one of the hardest Woods, be worked before it be sufficiently seasoned, it will be very fragile, and subject to break; so that curiously worked Vessels exposed to the Sun, have broke in pieces: And it hath been observed likewise, That several Cavities have been found in the Substance of it, full of a certain Gum, which some People much esteem in Venereal Distempers; to which may be added, That in the Seasoning of this Wood, for some particular uses, it is requisite to keep it longer than others, so that less than twenty Years will not make it fit for some uses. From whence we may infer, That if this Wood requires so long time to acquire its utmost Compactness, and to evaporate its Watery Parts, the Motion of those evaporated Particles, must not only be very lasting, and durable, but slow. And if it be allowed, that those Gummy Parts were collected in their Cells, after the Felling of the Tree, as it is highly probable, it will be further to our Advantage, because it shows how the Parts of a Gross Body do permeate the fine Pores of a very Solid and Inanimate Substance; where the Motion must need be very insensible and slow. But what is more strange, I am informed, that the Wood of which certain Musical Instruments are made, sometimes, though a much softer Wood than Lignum Vitae, requires at least forty Years Seasoning, and does not acquire its best Resonance under Fourscore. But further, That there is not only a Change of Texture in Solid Vegetable Substances, but even in Stony Concretes, appears from what is observed in Building; Observations made in Quarries. where some Walls acquire not their Utmost Solidity under forty Years. To which I shall add, what is further observed in sums Quarries by Masons: And First, that there are Marchasites to be found, which being much more hard than Stones or Marble, and which consist as well of a Metalline, as a Stony Substance; yet have such a Degree of Motion in their Parts, as not only to burst, but, if long exposed to the Air, to be covered over with Vitriolate Efflorescences. To this I shall add, That an Ingenious Friend of mine had a Turquoise-Stone, in which there were certain Spots of different Colours from the Gem itself, which were observed to shift their places several times; which that there might be no doubt of, I employed one to take the Picture of it with those Spots in it, at several distant times, one after another, which Pictures, when compared, showed, that the Spots had shifted their Places; having passed up and down through the Substance of so solid a Gem, very slowly, in a Figure as irregular. And I am informed by a Jeweller, that he once had one of these Stones, which had a different Blue in two several Parts of the Stone; and that, in some time, the one overspread the whole, and mixed with the other: And an Ingenious Friend of mine told me, That he had observed a certain Cloud in an Agate, to move several times from one place to another. Motion in the Parts of . But there is not only an Intestine Motion of Parts in such Solid Substances as these, but in Bodies looked upon to be of the Closest and most Compact Textures; for I have now a Diamond by me, which being rubbed, will easily become Electrical, and shine in the Dark; which Qualities cannot be added to it, without a Change of Texture; and that in altering that Texture, there is an Internal Motion of Parts, will easily be evinced; because, otherwise the Texture could not be changed; and further, because a very gentle Agent is sufficient to put the Parts of a Diamond in Motion. And to this Relation I shall add, That I have often observed, a Dulness and Clearness to succeed each other, in a Diamond, which I now have set in a Ring with the Former, which Changes could be attributed to no Manifest Cause: And I have observed no less suprizing a Change, in the several Degrees of Electricity, which could not be effected by any Cause that I could think of: And I have been informed, by one who had a certain Hungarian Diamond, that it would acquire a much greater Degree of Sprightness, by lying some time in Water: From all which it appears, That Considerable Changes may be effected in Diamonds, by Agents, which, to Sense, Operate very gently. And if Diamonds are generated in the Earth, as I have observed other Stones to be; it is reasonable to think, that the Hardness of their Substance, proceeds from the Closeness of their Parts, depending on the Intestine Motion of their Insensible Corpuscles, by which they are brought to convene closer than ordinary: And this I am rather Inclined to believe, because I have been told by an Eminent Jeweller, That the Diamonds of late Years, are much more soft than those he formerly used to deal in: And the truth of this is further confirmed, by what Egrezes' a Frenchman writes of Diamonds, P. M. 17, 18. brought from the Mine, called Gazerpoli; the Sense of the Words is this: They are very clear, and of a good Water, but they cannot be ground by Mutual Attrition, except with Stones of the same Mine: for if one should employ for that purpose, the Stones of another Mine, those of Gazerpoli would be broken in pieces: They do also easily break upon the Wheel, and those that are not versed in the Knowledge of Stones, may be easily deceived in them. And the same Author, speaking of another sort of Diamonds, says, That they sweat a sort of Unctuous Substance, which being wiped off, as often renew its Appearance. And to these I shall add an Account of a Ruby, which is one of the hardest Diamonds, one of which a Lady, nearly related to me, wore upon her Finger; which would often change its Lustre, the Cause of which could not be assigned; tho' these kind of Phaenomena seem to be the Effects of some Internal Motion in their Parts, the Parts of Diamonds being capable of having their Parts put into Motion, without much difficulty. But tho' it be hence Evident, That there is such an Intestine Motion of the Parts of Diamonds; yet it may be thought strange, to find the like in so firm and compact a Body as Glass. But that the Parts of Glass are not always at Rest, I am induced to believe, by the following Observations. First, That several Plates of Venice-Glass, have cracked and broke in pieces, when no external Agent could have any Sensible Operation on them; which I conceive to proceed from a Redundancy of Saline Parts, which striving to fly away, break the Glass by their violent Motion; which Conjecture I am confirmed in, since it is commonly observed, The Parts of Glass in Motion. That there is a Saline Substance, adhering to the Surface of these Glasses in Cold Moist Wether. And I have observed in a Glass, into which too much Salt was put, to make it Diaphanous, several Cracks and Flaws, which it got in the Cold Wether: So that it rather appears to be a white, than a Glass-Cup at a Distance. And I, as well as those that deal much amongst Glasses, have observed, several to fly in pieces, when there was no outward Agent, to be the Cause of such an Effect; and I am informed by an Ingenious Man, who is Master of a Glass-House, That near a Third Part of a parcel of Glasses, flew in pieces of their own accord, after they had been kept for about five Years packed up. To which I might add several other Instances, to prove and illustrate the Doctrine above-delivered. For these Phaenomena may be, and are, very Naturally accounted for, by the Corpuscular Philosophy; for supposing, the Particles of Glass to be in a continual Elastic Endeavour to expand themselves, and fly away; and that several of those Particles are got together, it is no wonder that they break and dis-joint those Parts of the United Glass, which are least able to resist, and keep them from Expansion. And to Countenance this Explanation, I shall add, That several Alkalizate, or other small Parts of Matter, being enclosed in the Body of a Glass, it is always apt to break, especially at that place, from whence several Cracks spread themselves as from a Centre. But whether the Elasticity of these Parts, be promoted by any Subtle Bodies, which penetrate the Glass, I shall not now stay to examine; but shall rather proceed to acquaint You, That in a considerable Space of Time, the Texture of Glass may be so altered, as to be more unapt to give a free Passage to Aether itself, or any other Subtle Body, which could penetrate it before; and consequently those Bodies Endeavouring to make their way, tho' opposed by its Texture, cause a Proportionable Crack, or Dissolution of the Substance of the Glass. Observations concerning the Intestine Motion of the Parts of Glass. And to what we have delivered concerning Glass, these Observations are not altogether disagreeable; viz. First, That it is a Substance, which by being rubbed easily, becomes Electrical; which is an Argument, that the Parts of it may without any great difficulty, be put into Motion. Secondly, The Parts of Glass may fly asunder, if the Neighbouring Parts be put into Motions disagreeable to each other; which is evident, if a hot Glass be immediately put into cold Water: for the Motion of its Corpuscles, being externally checked, those which within remain in a violent Agitation, cause a sudden Disruption. To which may be added, That tho' one would think the Particles of Glass were so fixed, as to become unfit to alter their Figure and Shape; yet their Parts continuing in some Degree of Agitation, they may, by invisible and insensible Agents, be so worked upon, as to be forced to alter their Shape and Size: In confirmation of which, it may be observed, That White and pure Transparent Glass, will in a little time, become very unfit to be put again into the Moulds they were first cast in. But tho' I have mentioned both these Methods, by which the Cracking of Glasses, may be accounted for, to show, that which soever of them we allow, they will be Proof of an Intestine Motion in the Parts of Glass; yet I will neither examine or determine which of them is rather to be relied on; but shall only observe, That the Motion of their Parts must needs be very slow; since it is so long before it shows its Effects. And now to conclude, tho' from what hath been delivered, it may be expected that I should draw Consequences, to determine whether there be absolute Rest in Bodies, or no, I shall omit that, and only intimate, That it is not absurd to doubt, nor improbable to think, that there is not; since it hath been discovered in Bodies, which are usually esteemed, most Quiescent. CHAP. XV. Of the great Effects of even Languid and unheeded Local Motion. THO' several Mathematicians, as well as Philosophers, Several Phaenomena arising from unheeded Causes, Comprised under the following Propositions. have exercised their Industry in limiting the Laws of Motion; yet since several Qualities usually esteemed occult, may arise from a faint and unheeded Motion of the Parts of those Bodies, to which they are attributed, I shall consider the Extent of local Motion a little further: But before I proceed to consider the particular Effects of languid and unheeded Motion, I shall first premise, in general, what I have elsewhere upon another Occasion intimated, viz. That we are not to consider Bodies, barely as so many Portions of Matter endowed with particular Powers; but as Bodies whose Particles are variously figured and modified after a peculiar Manner; so as to act or to be acted on by those Bodies which are about them; yet not wholly to derive their Effects to the Influence of external Agents, but in a great Measure from the mutual Action of one Part of Matter upon another. But there are several other Circumstances of local Motion, besides what we have taken notice, which are not to be discerned; and therefore I would not be thought wholly to attribute the Phaenomena of a Body to Motion only but to a Concurrence of several other Causes; but to avoid tedious Preambles, I shall take notice that the Reasons why some Men slight or overlook the strange Effects of languid Motion may be comprised under the following Heads. I. Prop. I. Men are wont to overlook the great Efficacy of Celerity, in Bodies which are very small: And especially, if the Space which they move through be but small. What strange Effects may be derived from rapid, tho' undiscerned Motion, we have a convincing Instance in Bullets, which by reason of their swift Motion, are able to effect more than those battering Engines of the Ancients, which were of a Bulk in comparison of Bullets, which are shot out of the largest Canons: To this I might add several other Instances, but I shall rather proceed to allege, in favour of the second Part of the Proposition, that I have often observed, That the Particles of Iron, which fly off Iron Rods, when they are turned, affected my Hand with a sensible Heat, if held at a small Distance; and it is likewise observed by those who work in Brass, That the Particles which fly off upon turning, affect their Eyes, as well as other Parts, with an offensive Heat; so that an experienced Workman showed me a Blister upon his Hand, which was raised by the intense Heat of Particles of Brass thrown off by a rough Tool. And I am further informed, That in turning of great Guns, the Parts which fly off are so hot as to burn the Fingers of those, who offered to take them up: Amongst which Observations it is to be noted, That Brass acquires a much greater Heat in turning than Iron. And to these Observations I shall add, That not only the Parts of Metals, but Wood, will become in some Measure warm, by being put into a rapid Motion by the Force of the Turner's Engines; from which Instances it appears how considerable are the Effects of a rapid, tho' a short Motion. And we have Instances of this kind no less remarkable in Vegetables, where a good Cane by being struck with a Piece of Flint, emits Sparks not unlike Flint in a Moment of Time; and the like succeeds, if Loaf-sugar be dexterously scraped, so as to put its Parts into a brisk Agitation: But what is most worthy to be observed in Flint is, That its Parts being put into a brisk Motion by another Piece of Flint, will not only assume the Form of Fire, but as the Ingenious Mr. Hooke hath observed, will be vitrifyed, tho' in Glass-houses both an intense Heat and an Addition of some Borillia are requisite to bring Sand or Flint to Fusion and to vitrify them: And that this Vitrification is made of the Portions of the Flint put into a brisk Motion, I am induced to believe, because one Piece of Flint will strike Fire upon another, without the Assistance of a Piece of Steel; and Fire may not only be struck out of Flint, but Bodies much harder, as Diamonds, which when grated on in a Mill have their Parts put into such a Motion, as to constitute Flame, though the most intense Degree of Heat will not dissolve them; and even the Parts of fluid Bodies, if put into a brisk Motion, may have considerable Effects upon solid Bodies; for whether, the Beams of the Sun consist of Particles, which flow in direct Physical Lines from the Sun, or are only contiguous Matter, as the Cartesians think, put into a successive Motion, yet it is enough to countenance what is here delivered, that that Matter thrown into a Focus will melt Lead, Tin, or foliated Silver and Gold, and in a little time set green Wood on Fire. And how the small Parts of fluid Bodies will affect consistent and solid ones, will be further evident from Instances alleged under the fourth Head. The Effects of Lightning. What I shall further offer here is the Strange Effects of Lightning, which, as several Histories, etc. testify, by the Motion and Minuteness of its Parts hath melted Metals in a Moment. Nor are the Effects of the Air in a Wind-gun upon a Bullet less to be admired; its Parts upon the Account of their Springyness, being put into a violent Motion; for when the Air is permitted to expand, by affecting the Bullet no longer than whilst it passes through the Barrel of the Gun, the Bullet acquires such a Degree of Motion, as, upon its being shot against a Plate of Metal, to be pressed into the Shape of an Hemisphere; and the Particles of the Bullet will be put into so considerable a Degree of Motion, by striking against the Plate, that I could scarce hold it betwixt my Fingers. II. We are inclined to think, Prop. II. That the insensible Motion of so soft Bodies as Fluids, can scarce have any sensible Operation on solid Bodies. By the Motion of fluid Bodies I would be understood to mean, not that which may be discovered by the Eye or Touch, but the unpercieved Motion of their insensible Parts; of the Effects of which, I might allege several Instances from the Operations of Sounds upon solid Bodies; for upon the Discharge of great Guns, the Sound of their Explosion is not only heard a great way; but the expanding Gunpowder gives such a Motion to the Air, as to enable it to break Glass Windows at a considerable distance. And tho' to this it may be objected, That since the Cannon stands on the same Piece of Ground with the Houses whose Windows are so broke▪ the Effect may proceed from a tremulous Motion continued by the Soil it stands on, yet the following Instance will make it appear, That the Parts of a Liquid being put into Motion may have such Effects; tho' it is not to be denied, but that a tremulous Motion may be given to the Earth, so violent as to be extended to a greater Distance; the Instance is, That the Water hath been put into so violent a Motion by an Engine contrived to sink Ships, that it shaked several Ships which were at a considerable distance, so strongly, that those who were on the Decks could scarce stand. And in the late great Sea-Fight between the English and the Dutch, tho' they engaged at several League's Distance from the Hague; yet the English Ambassador, who was then Resident there assured me; that the Guns were not only heard thither, but that his Chamber Windows were considerably shaken. And some Bodies are so apt to receive Impressions from the undulating Motion of the Air, as to be sensibly, tho' not visibly affected; of which Simon Pauli in his ingenious Tract De Febribus Malignis p. 71. gives an Instance in these Words. Atqui aeger ille Gallus brachio truncatus, octiduum quidem superfuit, sed horrendis totius corporis Convulsionibus correptus; qui quoque (ut & illa addam Observatione dignissima,) dumb in Domini sui aedibus ad plateam Kiodmoggerianum, Romanè, Laniorum appellares, decumberet, ac me ac aliis aliquandiu ad Lectum illius considentibus quidem, sed nobis non attendentibus, explodentur tormenta bellica ex Regiis ac Praetoriis Navibus, sinistra truncum dextrâ brachii fovens ac complectens, toties quoties exploderentur singula exclamabat au, au, me miserum! Jesus, Maria, count undor penitus, adeo permolesta & intolerabilis illi erat Tormentorum explosio, & quidem ex loco satis longinquo, terrâ non firma aut contiguâ, verùm super salo aut mari Balthico, instituta: From whence it appears, that a Fluid Body may operate considerably upon a Solid, tho' the Motion which causes such Effects be not perceived: And of the Truth of the foregoing Relation, I am further assured, by the like Effects produced in the shattered Bones of wounded Men at Sea who have had sensible pain upon the Discharge of the Enemy's Cannon. But lest in the aforementioned Instances it should be alleged, that these Sounds are rather propagated by the Earth, which the Bodies which received the first Impression leaned upon, than conveyed through the Air; I shall subjoin, that the Sound of Thunder is not liable to such Objections, since it can only be propagated through the Air; yet the Parts of the Air are in so Powerful an Agitation; that they have been observed to shake, not only Houses but several Ships at Sea. But these Effects will not be thought strange, if we reflect on what hath been observed to be produced by the Celerity of the Motion of the minute Parts of a Body; especially if we likewise consider, that Sounds are propagated with greater Celerity than any thing we know besides, in our Sphere. For tho', as Marsennus takes Notice, a Bullet moves 240 Yards in the sixth Part of a Minute; yet I have observed Sounds to move 400 Yards in the same space of time. But tho' (it being granted that Sounds may be conveyed through the Air,) the Concussion of Houses or Ships at Sea might be supposed to arise from the Impetuous Motion of the Medium, violently shaken by an intense Agitation, where those Sounds were originally formed; yet I conceive the Effects which those Sounds have on Bodies which are placed upon the Surface of this Globe, depend in some measure on the Dispositions of those Bodies to be worked upon by such. But to put an end to Instances alleged in Proof of this Proposition I shall add an Observation made by the Experienced Platerus, which shows, that a Solid Body may have such a Disposition as to be capable of receiving Impressions from the languid Motion of Air; for lib. Observe 1. p. 185. He says, Faemina quaedam in subitaneum incidit morbum, viribus subito prostratis, se suffocari indesinenter clamitans, etsi nec Stertoris nec Tussis aliqua essent Indicia, maxim verò de aura quadam adveniente, si vel leviter aliquis adstantium se moveret, quae illam opprimeret, conquerebatur, seque suffocari, si quis propius accederet, clamitabat: Vix dum biduum in ea anxietate perseverans expiravit: To which he adds, Vidi & alios aegros de simili aura, quae eos, si quis illis appropinquaret, in suffocationis periculum, induceret conquerentes, quod semper pessimum est signum deprehendi. III. Prop. III. Tho' the Number of Insensible Parts of Matter put into Motion, enable them to perform several things, yet they are usually slighted because invisible. The Effects of some subtle Parts of Matter are usually esteemed very inconsiderable, by those who imagine, that these more subtle Effluvia of Bodies only Act upon the exteral Superficies of others: But if we consider, that those Effluvia are not only very Numerous, but of convenient Figures and Sizes to penetrate into the inmost recesses of Bodies they work upon, we may attribute more powerful Effects to them than Men usually are wont to do; for as the Motion of the Effluvia are more or less strong, and numerous, they may either disjoin or otherwise alter the Textures of those Bodies. As in an Anthill, whose Soil is full of Eggs, by the Number and Motion of those little Infects; the Eggs which are up and down interspersed betwixt the Parts of the Earth, will presently be separated and displaced; or as the Leaves and Boughs of a Tree are variously bend and broken off, by the force of the Invisible Parts of the Air which passes through it. But to come to Instances which may more Illustrate what we are about; That the subtle Parts of Matter whose effects are less taken Notice of, are enabled, by their Size and Figure, to disjoin the Parts of Bodies they work upon; we have an evident Instance in Sugar, and Amber thrown together into Water; for the Water presently divides the Parts of the Sugar, and totally dissolves them; whereas the Amber continues unaltred. To which Instance may be added one of no less Force, afforded by Chemistry; for if you pour limpid Water, upon that consistent Substance, which remains after an abstraction of five Parts of Oil of Vitriol from one of Mercury, and shake the Mixture, the Calx will presently exchange it's White for a Limon-colour, the Texture of the whole Mass being presently altered, And how powerful the minute Parts of some Bodies are, we may further observe in Spirit of Wine: For if a Piece of Metal be held in the Flame of it, these subtle Particles presently penetrate the Substance of that Solid Body; and so exagitate the Parts of it, as to put them into a Motion strong enough to Cause a sensible Heat. And we have not a less remarkable Instance of the Force of unheeded Agents in Animal Bodies and the Effects of those invisible Spirits which move through the Nerves, which by such weighty Masses of Matter, as the Bodies of some Animals, are violently moved up and down: To which may be added, that by the bare insinuation of Moisture into the Pores of a Rope, it may be so contracted, as to raise above sixty pound weight, above the place those Weights were suspended at in dry Wether. And tho' Metals will endure the Heat of a Red-hot Crucible, yet may they easily be melred with the Flame of a Candle, if the Heat and Activity of it be promoted by a Blow-Pipe. And how much more able the Parts of an Agent, are to operate upon a Body, when they are intimately mixed with that they are to work upon, than Superficially, appears from Tartar, which is much sooner calcined, if Nitre be so mixed with it, that upon Deflagration, the Flame may be commixed with all its Parts, than if it only acts immediately on the Outside. The Effects of a Lead-stone upon Filigns of Iron. But to allege Instances, which will be of more Force; tho' the Effluvia of a Loadstone be very minute, and the Body of Iron or Steel very solid; yet I have seen a Magnet, whose Effluvia were so powerful, as to attract and sustain fifty times the weight of the Stone itself. And to make it appear, how probably the Effluvia of a Magnet may change the Texture of solid Steel, and by that means endow it with those Qualities, which Iron usually derives from it; I placed Filings of Steel upon a piece of Paper, holding under it the Pole of a vigorous Loadstone, by the Effluvia of which, the Filings were presently so ranged, as to representseveral Needles, or Pikes, made up of Particles of Iron, sticking one upon another; and these might be moved up and down, by removing the Loadstone, from one place to another; but as soon as the Loadstone was removed from that place, to such a Distance, that it's Subtle Emanations had no longer any Influence upon the Powder, the Parts of it presently lost that order, and fell into a confused Heap, as before that Loadstone was applied. Again, tho' the Particles of Water be so small, as to be Invisible, and their Motion very weak; yet is it so powerful, that upon Freezing, the Expansion of the Frigorifick Parts are strong enough to break Bottles, not only of Glass, but Metal, and the Expansion oftentimes is so violent, as to exceed the Force of any other Body in expanding (except Gunpowder) that I know of. CHAP. XVI. Of the Propagable Nature of Motion. iv It is usually not sufficiently taken Notice of, Prop. VI how Local Motion may be propagated through several Mediums, and even Solid Bodies. IT is usually thought, because some Bodies when they strike against Solid ones, commonly fly back, That the Impulse of that Body is not able to put the other into Motion; but that the Parts of a Solid may be put into Motion, and that that Motion may be propagated through such Consistent Substances, is evident, if we strike a piece of Timber slightly upon one End: For by that means, the Motion caused by that Impression, will be carried on to the other. And I have by Experience found, that having drawn the Point of a Pin upon the Brim of an Hemispherical Vessel, which was made of Bell-Metal, which is much harder than Steel, I found it, from a very slight Impression, to produce such a lasting Sound, as was an Argument, that the Parts of the Metal were not only put into such a Vibrating Motion, as to communicate it to the Air, but to continue it successively round the Brim of the Vessel, till the Sound ceased. And the like Propagation of Sounds I found to succeed, tho' the Point of a Pin were but struck upon that Vessel, which was seven Inches in Diameter. And indeed the Propagable Motion of Solids, when they are acted on by Fluids', is not less remarkable; since the Parts of a Bar of Iron, or Glass, may be put into such a Motion by Heat, as to have it continued to some Distance from the place where the Fire first worked upon them, tho' it be capable of being propagated much further in the former of the two; which shows how much the Textures of Bodies dispose them to be differently worked upon by the same Agent; and how much a Convenient Texture disposes them to be worked upon at all. And it may be further observed, That it is looked upon as a Sign of the firm Connection of a House, that upon the Clapping of a Door, the whole shakes; and it is likewise an Argument of the Communicableness of Motion, whether it depends on the mutual Contact of the Door, and the Posts it shuts against, or upon the Impression made upon the included Air by the Door; for the former shows how a Solid may propagate Motion amongst Solids; and the Latter, how it may give Motion to a Fluid, and Vice versâ. But further, it is asserted by Seneca, that upon the Explosion of those Subterraneali Exhalations, which are the Causes of Earthquakes, the Tremulous Motion of the Earth is continued above two hundred Miles: And Josephus Acosta witnesseth, That it hath been continued for three hundred Leagues in the Kingdom of Peru: And Learned Writers in the beginning of our Age (1601) witness, that the Motion of the Earth was so violent, as to shake most part of Europe, being propagated through most part of Asia, Hungary, Germany, Italy, and France: And I have frequently observed, That the House I have been in, hath sensibly shaken, by the Tremulous Motion of the Earth it stood upon, propagated from some Coach or Cart, which moved at some distance upon the Ground; and some observing Scouts say, That, by the Motion of the Earth, they can discover the Approach of a Troop of Horse at a good Distance. And, to conclude this Member of our Discourse, if such Disproportionate Causes, can produce such Effects in Inorganical Bodies, well may they in those that are Organical, where there is only wanting a small Cause to call in the Assistance, and to determine the Cooperation of others; as the Tickling of a Feather in the Nose, by Determining the Tendency of the Spirits, Causes Sneezing: And I remember, being once held with such a Distemper, as deprived me of the use of my Hands; If, in the Summer, a Hair were but blown upon my Face, and continued there long, it would put me into Convulsions and cause me to faint. Motion may be propagated through different Mediums. But to determine another Member of this Proposition, viz. Whether Motion may be propagated, through several Mediums, or terminates at the utmost Limits of the Medium it was begun in, I shall offer the following Experiment; viz. I caused a Glass-Receiver to be blown with a Button, upon that part of the Internal Superficies which was uppermost; and suspending a Watch by a Chain, which was fixed to a Soft Body, fastened upon the Button, I luted on a Receiver, to prevent a Communication betwixt the External and Internal Air; yet the Sound of the Watch might be percived by holding One's Ears over that place, where the Watch was suspended. And I have often felt not only the striking of a Watch included in a double Case, when I have worn it in my Pocket, but even the gentler Motions of the Balances. To the Foregoing Instances, I shall add, That upon sudden Claps of Thunder, the very Beds have been perceived to shake, by those that lay upon them: And Agricola, de Nat. eorum quae fluunt è terra, Lib. 4. cap. 7. says, Si Animal deijicitur in Antrum, quod est in Carelia, Regione Scandiae, erumpit, ut perhibent, sonus intolerabilis magno cum flatu: Si leve pondus in Specum Dalmatiae, quamvis, inquit Plinius, tranquillo die, turbini similis emicat procella. But there are still some who are unwilling to believe, That Motion is propagable through Liquid Bodies; at least to any considerable Distance, because of the easy Session of their Parts: But the contrary easily appears, if we allow of the Corpuscular Notion of Light; by Considering, not only how far the Rays of Light are impelled, and propagated from a small Light, but from the fixed Stars, which are placed at so immense a Distance. But to proceed to Instances, not so liable to Objections, that the Parts of Liquids', tho' in Motion, and Separate one from another, may communicate Motion, and propagate it a considerable way, is evident, by casting a Stone into the Water; which, by that Impulse, will successively propagate Motion in the Mass of Water; which appears by the Curling and Circular Streams which flow from it: And I am told by one who was used to Fish for Whales, near Green-Land, that sometimes, upon the Thawing of the Ice, it would give such Cracks, as to cause Sounds much louder than Claps of Thunder; and when huge pieces of Ice upon a Thaw, fell into the Sea, they caused such a Disturbance in it, as at two League's Distance to raise a considerable Storm. And tho' some People are apt to think, That, the Air, being a Body much more Fluid than Water, Motion is less propagable in it; I shall intimate, that even in that Medium, a very small Sound is propagated, much further than we think of; for tho' we are not able to take Notice of it, beyond the Place where we stand, yet we may learn from Echoes, that the Undulating Motion of the Air is continued a good way further; and it is not improbable, that it is continued further than the Place where the Echo is made; since the Learned Fromundus, Professor of Philosophy at Louvain, in the Year 1627., says, That at the Siege of Ostend, the Noise of the Cannon was heard an hundred and twenty English Miles. To which may be added what Verenius Geogr. Gen. Lib. 1. Cap. 19 relates, as observed by Traelichius, at the Mountain Carpathus in Hungary: His Words are these, Explosi in ea summitate Sclopetum, quod non majorem Sonitum, primò prae se tulit, quam si tegillum aut bacillum confregissem; post intervallum autem temporis murmur prolixum invaluit, inferioresque Montis parts, Convalles & Sylvas opplevit: Descendendo per Nives annosos intra Convalles, cum iterum Sclopetum exonerarem, major ac horribilior fragor, quam ex Tormento capacissimo inde exoriebatur; hinc verebar, ne totus Mons concussus, mecum correveret; duravitque hic Sonus per semiquadrantem horae, usque dum abstrusissimas Cavernas penetrasset, ad quas Herundique multiplicatus resiliit, & talia quidem objecta concava in summitate. se non illico offerebant, idcireo fere insensibiliter primum Sonus repercutiebatur, donec descendendo Antris & Convallibus vicinior factus ad eas fortius impegit. V The Effects of the Particular Modifications of the Invisible Motions of Fluids', Prop. V. on Animal Bodies disposed to be worked upon by them, are not usually sufficiently noted. Tho' it may be thought strange, That the Impulse of so 'Slight and Languid Parts of Matter, as those of Air, should by their Motion, produce any Sensible Effects; yet, if we consider what a number of those Parts succeed each other, it is less to be admired, that the Effects of their Joynt-Action should be considerable, since we see, that a Pendulum of a Clock is continued in a swinging Motion, by a very Languid Force, and the Air may be put into a Motion so powerful, either by the Vibration of the Strings, or the Mechanical Form of a Musical Instrument, or Scraping the Edge of a Knife upon Metal, as, to cause an Involuntary Excretion of Urine upon a Body rightly disposed, as it happened to a Knight of Gascony; or, to cause that Effect which is usually termed, Setting the Teeth on Edge. Besides which Instances, of the Effects of so Languid a Motion as that of the Air, I shall add, That I had a Servant, whose Gums would presently bleed upon tearing of Brown Paper: And Sir Henry Blount, as well as Kircherus, relates a Story of the like Nature; the former having observed in Grand Cairo in Egypt, a Nest of Serpents, which upon the Sound of a Citron, would presently crawl out of their Nests; and upon a Cessation of that Sound, run away again as fast: and the Latter tells us of a Fish about the straits, which divide Sicily and Italy, which will be enticed to follow the Ships which pass by that way, by the Sound of a Musical Instrument. And that these Effects are produced by a sort of Disposition in those Bodies, to be worked on by such Sounds may be confirmed, by observing, That a Man is sooner affected and awaked out of Sleep, by the Agreeable Sound of his own Name, than any other. And the Effects of a gentle, if a Surprising Sound, are no less Remarkable, which will raise a Body from the Ground, which could not be so poised with some hundreds of Weights. But the most Eminent Instance is in Persons bit by a Tarantula, who, upon the Playing of a peculiar Tune, are compelled to dance, as long as it continues, tho' other Tunes have no such Effects on them; the Truth of which Relation is confirmed both by Epiphanius Ferdinandus, and several Others: And I was acquainted with One, who told me, That a certain Lady could not forbear Weeping, when she heard a particular Tune played; and I have found several times a sort of Chillness upon myself, upon the Repetition of two Verses in Lucan, especially when I have been any thing Feverish. To which Instances of the great Effects of Languid Motions, may be added, what is produced by the Subtle Effluvia, the Rays of Light causing those that come out of a dark Place presently to Sneeze: And Colours, which are but several Modifications of Light, have not less considerable Effects; which is evident from the Influence Red Cloth hath upon Turkey-cocks: And the Learned Valesius, relates a Story of a Person, whose Eyes were much offended by Red Objects, which influenced him so much, as to cause an Effusion of Humours in the Adjacent Parts. VI Men do not consider the Effects of Fluids upon Inanimate Bodies, Prop. VI upon the Account of a Particular Texture and Modification of the Agent, and the Patient. That the Peculiar Modifications and Relations which Bodies have to each other, upon that Account, may contribute much to the Effects which the Languid Motions of the Air produce; and that upon that score, a weak Motion of it, may cause more considerable Effects, than Louder Sounds, not so aptly modified; I shall produce several Instances: For not to urge, That the String of an Instrument may be made to Vibrate itself, by the Motion it receives from the Instrument, and which that Instrument first received from another String, I shall rather offer the following Instance; viz. That a Strong Wire being made use of amongst other Strings on a Musical Instrument, it was observed, that the Wire would be made to tremble, by the Impulse of the Air, caused by a Sound which was made at a Distance, tho' the other Strings were not sensibly affected; but in this Experiment it is to be noted, That a peculiar degree of Tension is requisite, to afford the Forementioned Phaenomenon. To this Experiment it may be added, That I have not only observed, that by making a Determinate Sound at some Distance from an Hemispherical-Glass, it would sensibly ring; but I have likewise taken Notice, That having screwed several Strings of a Musical Instrument to a different Degree of Tension, and likewise placed several Glasses at some Distance, those Strings being put into a strong Degree of Tension, would cause one Glass to ring without affecting the other; and if the Tension of that String was altered, it would affect another Glass, but not the same: And what is more Remarkable, is, That tho' a String wound up to a Determinate Degree of Tension, would affect such a Glass; yet if the Foot of the same Glass were a little broke, it would not till its Tension was altered. And I have taken notice, That upon the Opening of some Stops in an Organ, the Sound hath been so considerable, as not only to cause the Organist's Seat to tremble, but a Seat in the Church, which was at a considerable Distance; and I could easily discern with my Fingers, that the Sound not only caused the Seat, but the Borders of my Hat to tremble: Which Instances show, that the Effects of that Sound are not so much to be attributed to the Violence of it, as to the Dispositions in such Bodies to be acted on by it. And to prove, That Languid Motion may have considerable Effects upon Bodies, both Solid and of considerable Bulk, I shall bring the following Instances: The First is, That an Ancient Musician affirmed to me, that playing upon a Basse-Viol, he found, that when he struck a certain Note, it had always such an Effect upon a Casement, in the Room where he played to one of his Scholars, as to cause a Jarring Noise. A Second Instance is, That I observed in a certain Vault, that tho' a Musician varied his Notes on purpose, to make Trial whether they would resound in the Arch, it would answer to but one Note; and I am told, that there is the like peculiarity in most Vaults. VII. Some Bodies are thought to have their Parts in an Absolute Rest, Prop. VII. when they are only in a state of Tension, or Compression. Tho' the External Superficies of a Body, seems to argue, That its Parts are at Rest, since it retains its Proper Figure and Dimensions; yet it is not improbable, but that those Corpuscles which compose it, are variously moved amongst themselves, or in a Tendency to Motion; An Instance of the First of which, we have in heated Iron, whether made hot by Actual Fire, or Hammering: For tho' the Eye can discern no Motion at all amongst its Parts, yet the Touch perceives it manifestly hot: And tho' the Lath of a Cross-bow, or the String of a Bow, be looked upon, when bend, as Bodies at Rest, yet the Springiness of the former, and violent Separation of the Ends of the Latter, when cut, manifestly demonstrates, that they were only in a state of Tension: To which might be added several Instances, taken as well from Nature as Art. Of the Latter sort I have observed, That amongst Glasses, which to all appearance were well baked, several Months after they were made. some of them flew in pieces of their own accord, which they scarce ever fail to do, if they be taken from the Fire, and suffered to cool suddenly. The like to which I have observed, in a Metalline Glass of my own Preparation, which would shrink so much when removed from the Fire, as, if suddenly cooled, to fly in pieces. And if a piece of Copper heated to a Redness, or a Whiteness, be, upon Cooling, held over a piece of Paper, several Fleaks will presently fly off it; which seem to be Vitrifyed Metal, which, upon their shrinking, when exposed to cool, fly asunder, like the Strings of a Musical Instrument in moist Wether. And upon this Occasion, to show how much Metals may shrink, I shall add, That I have found, that tho' a piece of Iron, when hot, would not go into a Cavity made in a Metalline Body for that purpose; yet when exposed to the Air, and cooled, it would shrink so much, as to be able to enter it: And to this, I shall add two Notable Observations; viz. First, That a certain Artificer, having cast a number of Metalline Concaves, found, that tho' he took care to keep them from being exposed to the Air, whilst cooling, and tho' they were of a considerable Thickness, and much harder than Iron; yet when they were leisurely cooled to a certain degree, they would crack with a great Noise. The Second Observation is, That an Expert Artist, having cast a quantity of Bell-metal, and permitted it to cool about 12 Hours, upon the Area of an Iron Instrument, he found it considerably shrunk from the Instrument, and cracked in several places: And the like Accident hath happened in Brass: for an Artist assured me, That having cast a Ring of Brace, about a Cylinder of Iron, upon cooling, it was so much shrunk, as to leave a Crack quite through on one Side. From which Experiments it seems reasonable to infer, That a Body may be brought to a state of Tension, as well by being expanded by the External Force of the Fire, as any other external Agents; and also, That the Preternatural states of Bodies, which they are brought into by some Agents, are to be looked upon to depend on their Previous Dispositions, since tho' the Moisture of the Air will not cause a String of an Instrument to crack, which is moderately wound up, yet if its Tension be much stronger, it presently flies in pieces: So likewise, if a Piece of Glass be hot in one Part, and cool in another, tho' cold Water dropped upon the hot Glass, will crack it, yet it will not have the same Effect on the Cool part of the Glass. From which and the rest of the Experiments contained in this chapter, it is apparent, that the Parts of Solids are not so much in a state of Rest, as of Tension, and Compression: To confirm which I shall add, That an Experienced Artist showed me a Lump of Matter, consisting of a great many agates lodged in a Cement much harder than ordinary Stones; which agates, he affirmed would sometimes, when taken out of the Cement, endeavour to expand themselves so powerfully as to fly in pieces, in a little time after. VIII. The Reasons why Languid Local Motion, Prop. VIII. and its Effects, are so much overlooked, is, because we are too apt to take notice only of the Visible Impressions of one Body against anowithout observing the Intestine Motions of Minute Parts. To prove this Proposition, I shall offer the following Experiments: And First, Having turned a Key in a Brass stop Cock, a considerable time, till the Metal, by frequent Attritions, became hot; I observed it at the last so to swell, as to stick fast like a Wedge, so that it could not be moved, till the Metal was again cool: And an Experienced Workman hath informed me, that in making such Instruments, before the Key could rightly be adapted to the Cavity it was to fit, he was forced to cool it several times in Water, to take down the Expansion effected by the Heat. To this Experiment, it may be added, That the Parts of a Drinking-Glass, will be put into Motion, by drawing One's Finger round the Brim; and that so violent, as to toss several Drops of the Water contained in it, a considerable height into the Air; and a Drinking-Glass Artificially cut by a spiral Line, being dextrously inverted and shaken, will have its Parts so manifestly vibrated up and down, as to acquire a quarter of an Inch in Length, without any evident injury to the Glass. And it hath been observed, by one who made use of hardened Steel Instruments to turn Iron, and shake off the Protuberances of that Metal; that in a little time it would acquire such a Heat and so lose its Temper, as to look blue or yellowish, if it was not timely dipped in a convenient Liquor, to keep it cool. To this I shall add, That having two or three times bend a Bar of Tin in my Hands, backwards and forwards, I found, upon the Breaking of it, that the internal parts had acquired a considerable degree of Heat. From which Experiment it appears, that Attrition of Parts, without a manifest Percussion, is able to cause a sensible Heat; and that not only hard, but soft Bodies, may do so too, I shall add the following Experiments, to evince, which is that an Artist having only rubbed Optick-Glasses with Putree, upon a piece of Leather, to polish them, told me, that they acquired such a degree of Heat, as sometimes to crack; tho' I am not unapt to think, that such an Effect might as well be attributed to a peculiar Motion of the Parts of Glass, which were too violent; since from the aforementioned Vibration of the Parts of a Drinking-Glass, it appears, That they may be put into a considerable degree of Motion, without Heat: And that, by a very easy Friction, such Bodies may acquire a Tremulous Motion, appears from the following Experiment, viz. having suffered melted Brimstone to cool, in a Vessel whose Cavity was concave, I rubbed the convex Superficies of the Brimstone, upon a Cushion for some time, and found, by applying my Ear to it, that the Parts of the Brimstone were put into such a Vibrating Motion, as to continue a crackling Noise for some time, after the Friction was discontinued. To which I shall add, That having rubbed two Stones taken out of the Bladder together, I found them to yield a strong Urinous Smell: And not only Sulphur will emit Sulphureous Steams, by rubbing it upon Cloth, but Diamonds themselves will acquire a considerable degree of Electricity; and I have one by me, which, if rubbed, will appear Luminous in the Dark. And that it may further appear, that a peculiar Modification of Motion, may contribute to the various Effects produced by it, I shall observe, That those Stones which Italian Glassmen make use of, afford Sparks of Fire by Collision; but if moderately rubbed together, they emit Exhalations; from whence probably proceed those offensive Steams, emitted by Glass; and what is most remarkable, and to our purpose is, tho' Glass when Red-hot emits no such Effluvia; yet if two pieces be dexterously rubbed together, they will send forth Steams copious enough and . And to show how brisk the Motions of the Parts of inorganical Bodies are, and how soon they communicate Motion to one another, we need but consider, how the Tremulous Motion of a Bell is continued successively round it; and how, all that time, it communicates that Motion to the Air about it; for that the Parts of it are so successively kept in Motion, appears from that Trembling Motion, which may be perceived by one's Finger: And it is further confirmed, because a Solution of the Continuity much deadens, and causes the Sound to be much shorter: And that the Air receives its Undulating Motion from the Impress of the Bell all that time, appears, if One's Finger, or some other Body be applied to it, which stops that Tremulous Motion. And that the Motions in the Parts of the Bell are very brisk, is evinced from what is generally affirmed, viz. That if a String be tied about a Bell, so as to check the Tremulous Motion upon the striking of the Clapper, it would break, some Parts being more agitated than others; so that the Disproportionate Motion compared with the Motion of the other Parts surmounting their Cohesion, they must consequently fly asunder: And, As a further Argument, that the Parts of the Bell are so agitated, I put Filings of Steel, and Drops of Water into a Hand-Bell, and observed, That, upon the Impulse of a Key, the Water shivered, and the Filings had likewise such a Motion given to their Parts, as enabled them to dance up and down. But to put an end to these Observations, I shall only intimate, That from what hath been said, it may appear, what considerable Effects may be caused by the Unheeded Motions of Invisible Parts of Matter, which are wont to be ascribed to other less Intelligible Causes. CHAP. XVII. A Supplement to the former Chapter of the Great Effects of Languid, and Unheeded Local Motion. TO illustrate what hath been delivered in the former Chapter, I shall add the following Observations: And First, That the Motion of the Air may act on Bodies duly predisposed, at a great Distance, appears from what the Learned Borellus De vi Percussionis, Prop. CXI. relates, viz. That being at Tauromenium in Sicily, about thirty Miles from Mount Aetna, when it first broke out, it was observable, that the Houses in that Town apparently shaken, especially those which were most directly situated towards the Gap; which, as that Author observes, must needs proceed from the Impression of the Air upon the Houses: for had it been the Effect of a Tremulous Motion in the Ground, all the Houses would have shaken alike, which was otherwise. To prove that Motion may be propagated through different Mediums, besides what hath been before delivered, I shall add, That the Eloquent Famianus Strada, De Bello Belg. Dec. 2. lib. 6. vel 7. says, That a very Stupendious Work being raised by the Prince of Parma, to prevent the City of Antwerp from being relieved by the River Scheld, an Engineer contrived to blow it up, tho' with Success not a little Tragical, by a Boat fraught with Gunpowder, etc. for it raised such a Commotion, that the Earth shook to the Distance of 36 English Miles; and the deep River was so agitated, as first to discover its Bottom, and afterwards to overswell the Banks; the Castle, together with Men, Cannons, etc. being violently tossed into the Air, together with a vast number of other Accidents horrid and dreadful. And to illustrate further what hath been delivered in the foregoing Chapter, concerning the Effects of Music on Bodies duly disposed to be worked on by it; I shall add, that an Experienced Traveller told me, That in the East Indies he saw Tame Serpents, which would raise themselves erect in the Air, except 3 or 4 Inches of their Tails, which they rested upon: And he added, That upon the Playing of some Parts of the Tune, they would be put into very brisk and surprising Motions, whereas when another Part of it was a-playing, they seemed to be half a sleep, and dissolved in Pleasure. Another Instance, which shows how much the Peculiar Textures of Bodies contribute to their Effects, is published by the Learned Marhofius, who relates, That Nicolaus Petterus had found out a Note, which, being loud and lasting, would, without visibly touching the Vessel, cause a Glass-Romer to tremble and burst; but if the Note were raised either too high, or depressed too low, it would have no such Effect. A further Instance of the Efficacy of Languid Motion is, That I once obtained several pieces of Glass, the Textures of which were so peculiar, that if the internal Superficies were gently scratched obliquely with a Pin, they would fly in pieces, tho' 6 or 7 times thicker than common Drinking-glasses. To show how much Motion, even in Solid Bodies, may be promoted by the Strokes of very weak Agents, I shall here relate, that several Urinals whose Parts were of a peculiar Texture, being rubbed with Sand and Water, had their Parts put into such a Degree of Motion, as, in a little time after, to break without any Cause to be observed, except that precedent Attrition of Sand. To make it evident, that the Parts of Solid Bodies, which seem to be at Rest, may have very powerful Effects, I shall add the following. Observations. First, That I have been informed, by a Famous Jeweller, That when he ground Rubies or Saphires, or other Precious Stones upon a Mill, their Parts would acquire such a degree of Heat, as to afford Light like Fire; the Light flowing from each being of the same Colour with the Gem it came from: And I am likewise informed by another, that when they have acquired a certain degree of Heat, the Edges would gape; and if the Motion of the Mill was continued, the Gems would fly in pieces; but if it was stopped, the cold Gem would be whole and entire. To this Observation it will not be amiss to add, That, I once placed a Bottle, to which was adapted a Glass-stopple, in my Window, and about a twelve Month after, as I was sitting in the Room, the Top of the Stopple flew off, of its own accord, leaving the other Part fast in the Glass; but the Parts of Solid Glass will not only fly in pieces of their own accord, but I have been informed, that sometimes, in the East-Indies; Diamonds themselves, are observed to burst asunder, without the Impression of any Visible Agent. THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. BOOK II. CHAP. I. Of the Systematical, or Cosmical Qualities of Things. Qualities proceeding partly from the Influence of outward Agents; as well as the Primary Affections of Matter CONSIDERING that the Particular Qualities of Bodies, depend on a certain Relation, which they have one towards another, by which they are adapted to Act or to be Acted on; I the rather choose to call the Qualities considered in this Chapter, Systematical or Cosmical Qualities; they not being the Effects of those primary Affections of Bodies considered barely as such, viz. Motion, Size and Shape; but of Bodies so diversified by those primary Affections, Acting mutually on one another: As Quicksilver is endued with a Power to dissolve both Silver and Gold, and an Aptitude to be dissolved in Aqua fortis. So that I would not be understood to mean, by Cosmical Qualities, such as may be attributed to the mutual Actions and Passions of Bodies, placed in some imaginary Spaces beyond the World, but placed in the Universe, as now Constituted, with a vast Variety of Bodies about them. This I have already hinted in the foregoing Chapters of Forms and Qualities; and therefore my design in this Chapter, is, to consider what Qualities a Body may Aquire, by the Impressions or Influence of Agents whose Effects are unknown, or not taken notice of. And though all these Phaenomena, which are usually attributed to the Laws of Nature, might properly be considered, in a Chapter that bears this Title; yet since those Agents most concerned in the Effecting of these Phaenomena are either the Stars, the subterraneal Parts, or the Aether and Atmosphaere we live in; I shall wave those, and only here consider, what is requisite to prove, that there are such real Qualities, depending on unheeded Agents, and the Ordinary Course of Nature; Our Notion of Cosmical Qualities grounded on the three following Propositions but before I proceed, I shall briefly intimate, that our Notion of Cosmical Qualities is grounded upon these three Propositions. 1. That some Bodies are altogether inactive, till they are acted on; and that others, are put into Action, chief by the Influence of these Catholic and unheeded Agents. 2. That there are several Bodies, which when put into Action, are subtle enough to insinuate themselves into the Pores of other Bodies, which they are by the Established Laws of Nature forced to act on. 3. That an Alteration of the Mechanical Texture of the Body, is enough to dispose it, or render it unapt to be worked on, by those unheeded Agents. And these three Propositions I shall endeavour to make out by the following Phaenomena and Experiments. To begin then with the first Proposition, viz. That some Bodies are altogether inactive, till they are acted on; and that others are put into Action, Proposition the first. chief by the Influence of these Catholic and Unheeded Agents. The first Part of this Proposition, I presume undeniable, if we consider, That till a Hammer, or some other Body be struck upon a Wedge, it wants the Power or Faculty of cleaving Wood, but when forced by the Impulse of that Body, which strikes upon it, the Wedge presently insinuates itself betwixt the Parts of that Solid, and divides them; As also, that a Knife is altogether unable to attract a Needle, till it hath received that Power from a Loadstone. But to proceed to the second Part of the Proposition; I shall, to what I have elsewhere observed (viz. That the Property of a Burning-Glass, in respect of its Effects, does not proceed from the Convex Figure, considered as such, but the Rays of the Sun cast into a Point) add the following Instances. The first is, That a Bar of Iron, by standing a considerable time in a Window, in a perpendicular Line, will acquire a considerable degree of Magnetism, by the Influence of Invisible Agents; and several Magnetical Qualities which it had not before. Secondly, That tho' a flat Piece of Marble, considered barely as such, hath not a Power to raise any Body by a bare Contact; yet if it be applied to another, whose Superficies is adapted to it; by virtue of the Constitution and Fabric of the World, and the concurrent Causes of Bodies about it, it may acquire such a Faculty, the lower Stone being boyed up by the Weight and Pressure of the ambient Air; yet, if these two Stones were contained in a Vacuum, they would not have such a Power to lift up one another. But to proceed to The second Proposition. The second Proposition; which is, That there are several Bodies, which, when put into Action, are subtle enough, to insinuate themselves into the Pores of other Bodies, which they are, by the Established Laws of Nature, forced to Act on. And here, though some of the Experiments to be related, might be also alleged in favour of that Aether or Materia coelestis, which some Philosophers have supposed to be dispersed throughout the World; yet the Invisible Agents, which are here to be mentioned, are only such as the Magnetical Effluvia of the Earth, and also the Air, in reference to its Spring and Weight. And first, Tho a Bar of Silver, and another of Steel, be exposed to cool, when red hot, with their ends directly North and South; yet the Textures of these two Metals being different one from another, the Pores of the Steel, being opened, and the Metal made pliable, it is by the Insinuation of Terrestrial Effluvia, endued with several Magnetical Qualities; and particularly, when poised, to point North and South; whereas Silver acquires no such Properties. And that it may be less strange, that the Earth should afford Magnetical Effluvia, which are imagined by some to be very spirituous Ones, I shall add, that having heated an Oblong Loadstone, and exposed it to the Air to cool, with its Ends pointing North and South, and so deprived it of its Magnetical Qualities; I could make either End to tend to the Southern or Northern Pole, as, upon Ignition, I suffered it to cool with one end directed either North or Southwards. To this it may be added, That if the Air be exhausted in some measure out of a Vial with an oblong Neck, and, upon its Immersion in Water, ones Finger, which prevented the retroadmission of the Air, be presently taken away; the Water will contrary to the Tendency of its own Gravity, presently fly up in the Bottle, being squeezed in by the External Pressure of the Air, lying upon the Surface of the Water, the Spring of the Internal Air, being so weakened, as not to be able to oppose the force of it; whereas in a Vacuo the Water would not be so raised, having no external Agent to boy it up. The Expansive force of Beans soaked with Water. Again, being desirous to know the Causes of Germination, and from what Causes, that powerful Intumescence of Seeds, when sown, proceeded, I filled several Vessels of Glass, as well as Earth, with common Beans, filling up the Intervals with Water, and tying the Corks fast with Strings; which being done, when the Beans had imbibed Water enough, their Intumescence was so powerful, as not only to break several of the Vessels, but a great many of the Strings which hindered the raising of the Corks. But that I might be more exact in estimating the Power of that Expansive Force, I put a sufficient Quantity of Beans and Water into a Brass Cylinder, whose Diameter was two Inches, and its Length six; which being done, and the Orifice of the Cylinder being likewise fitted exactly with a Plug, a Trencher was placed upon it, which was broad enough to bear a half hundred weight of Lead: In which Experiment it was to be observed, that in two or three days, the Expansive Force of the Beans had raised the Plug a considerable Height. And it may further be noted in such Trials, that as the Diameter of the Cylinder is larger, so the Expansive Force of the Beans are able to raise a more considerable Weight. How far these Experiments may confirm the Corpuscularian Philosophy, or whether that Force may be Mechanically explained by it, I shall leave the Reader to consider, and shall here only observe, That the Air, together with the Aether, may in a great Measure concur to the producing of some of the Phaenomena of Nature, which we imagine it very little concerned in; for besides the Effects which may be ascribed to the Pressure of the Air, it contributes to the producing of some upon another Account; it being easy to be observed, that Flesh may be preserved longer from Putrefaction, by being secluded from the Contact and Influence of the Air; and also, that the Light which flows from rotten Woods, and some putrefyed Fishes, will appear and disappear upon the Contact or Separation of ambient Air. Several Phaenomena produced by Virtue of Motion in the Parts of the Air. But for a further Proof, that the Air may effect several things, besides what it produces by virtue of its weight by the Insensible Motions of its Parts; I might add, that whereas a Piece of Paper being wet with Oil, hath its Pores so altered, as to be capable of transmitting more easily the Rays of Light; and the Air being impelled, by the Laws of Nature, presently acts upon it, and represents a great many Objects, by being reflected from those Bodies beyond it, which could not appear through it before. And if a large Box be so contrived, as to have one end of it open, and a Hole in the other end, covered with a Lenticular Glass; if the open end be made up with a fine sheet of Paper, and a small Hole be likewise made upon the Top of the Box; by placing one's Eye to the Lenticular Glass, one may discern upon the Paper the Lively Representations of External Objects, and their various Motions as well as Shape and Colours; which Phaenomena could by no means be exhibited, were not either some Insensible Corpuscles, transmitted in the Form of Effluvia from those Objects, or some other subtle Particles of Matter, directed by Local Motion from the Object to the Paper, and from thence to the Eyes. The Established Laws of the Universe Contribute to the producing of several Phaenomena. From whence it appears, that the Established Laws of the Universe, in a great measure, contribute to the producing of several Phaenomena, which arise from the Operations of insensible and unheeded Causes: For a further Confirmation of which I shall add, That if a Bar of Iron be held in a perpendicular Line; so that the lower end of it touch the Northern Point of a Magnetical Needle, it will presently drive it away; whereas, if the Position of that Iron Bar be so altered, as to touch that Point with the other end, it will, by a contrary Faculty, attract it, except the Iron Bar hath stood a considerable time in a Perpendicular Posture, exposed to the Air and the Magnetical Effluvia of the Earth, or hath lain a considerable time, pointing North and South, and so hath acquired a more durable Verticity. And if it should be asked; How a Bar of Iron acquires Magnetical Qualities. why, by such Postures, the Magnetical Qualities of Iron should be so much increased? it might probably be answered, that it proceeded from hence, viz. Because the Pores of the Iron, by lying nearer the Magnetical Effluvia of the Earth, have their Pores rendered more apt to receive and transmit the Effluvia of the Needle; so that consequently, that Part of the Iron which is most affected by those Steams, must become the stronger, and consequently the North Point of the Needle; for which reason, it must drive away the North Point of the Needle, and attract the South. But if on the contrary, the other end of the Bar be applied to the Needle, by a contrary reason, it being less Magnetical, it must attract it. But not to insist upon this Explanation of the Magnetical Qualities of a Bar of Iron, I shall only observe, that it is necessary in order to acquire a durable Magnetical Virtue, that the Iron should stand long in that Perpendicular Posture, which is sufficient to prove what I contend for, viz. That the established Laws of Nature are requisite for the Production of several Phaenomena, which would not be effected, were not those Laws observed. The Third Proposition. But to proceed to the third and last Proposition, viz. That an Alteration of the Mechanical Texture of a Body is enough to dispose it or render it unapt to be worked on by those unheeded Agents. This is evident from what is practised at Sea, it being the usual Custom for the Seamen, to throw Water upon their Sails to quicken the Motion of their Vessels, when pursued by Pirates; for the Threads of the Sails being swelled with Water, and the Pores by that Means made less, the Wind, not finding so free a Passage through them, must consequently have the greater Force upon the Sail-Clothes, and so drive the Ship forwards more swiftly. Another Instance of considerable Effects succeeding a very slight Alteration in Texture may be observed, when, on a windy day, a Chamber-Window is left open; for the Wind, which before only shook the Glass, will presently blow the Curtains about and other things in the Chamber, which are in a Disposition to be easily moved, as Dust, Papers, etc. But to proceed to Examples altogether not so gross, we may take notice, That though common Tartar will neither dissolve in the Air, nor easily in Water, yet when Part of it is driven away by Calcination, it readily dissolves and runs per Deliquium in a moist Air. To which may be added, that tho' a Loadstone by being heated in the Fire and cooled again, underwent no visible Change as to Shape or Size, nor for as much as could be perceived by the Eye, lost none of its Parts; yet, by an invisible Change of Texture, effected by the Magnetical Effluvia of the Earth, it may alter its Verticity according to the different Postures it is permitted to cool in: And the like Change I have observed in Iron, whose Verticity was altered by a Change of Texture, wrought by so weak an Agent as the Earth. To these we may add several Instances in liquid Bodies; and first, That, tho' Honey and Water mixed together in an undue Proportion, reserve each their distinct Natures; yet if four or five Parts of Water be added to one Part of Honey, by some subtle Agents or other, they are presently fermented, and unite into one common Mass; and I am assured, by a Merchant who lived several Years in the Canary Islands, That if a Hogshead of Wine close stopped be violently rolled along; the Texture of the Liquor would be so changed, that, if it were but about a Month old, one of the Ends would be burst out, and the Liquor lost. Another Instance in which the Texture of the Body disposes it to be so powerfully worked upon, we have in Glass, which upon a sudden Removal from the Fire into cold Water, is subject to fly in Pieces. But an Instance which is more remarkable is, That a hot Plate of Copper being permitted to cool upon some which were more moderately hot in the Fire, and thence removed upon a Plate; several Pieces like Scales would fly off it, when exposed to the Atmosphere; and To conclude this Chapter, I shall add, That the Bolonian Stone acquires such an admirable Quality by Calcination, that, by being placed in the Sunbeams for some time, it gets such a Degree of Luminousness, as to retain it a considerable time, when removed into the dark. CHAP. II. Of Cosmical Suspicions. THE World about us being stocked with such a Variety of Objects, and other things, too small or subtle to be discerned; it may not be unuseful, upon some Accounts, to propose Conjectures, where the Subject considered admits of no clearer Discoveries. Suspicion the First. And First, it is not without Reason I suspect, that, besides those uniform Parts of Matter, of which the Aether, by some Philosophers, is thought to consist, there are also several other Parts of Matter, which are differently disposed to work upon Bodies, according to the various Textures of those Bodies they chance to work upon; or according to the different Agents they chance to work concurrently with: And this Suspicion is not improbable, since the inquisitive Gilbert hath not only discovered the Magnetical Qualities of the Earth to be diffused on every side, but also it is commonly known that upon the Hunting of a Deer, several subtle Effluvia are left behind in the Air; which we should pass by unobserved, were there not such Creatures as Bloodhounds, endowed with Organs fitted to receive those subtle Steams. A Second. And it is not a little strange, that several Persons should have such peculiar Temperaments, as to be able to discover Pestilential Steams in the Air, for a considerable time before they are disposed to affect other Men; and that those Constitutions should be so disposed to be worked upon by Effluvia, by others not in the least discerned. And that there are such Bodies, as well as unheeded Effluvia, may be evinced by several Instances; as one which was remarkable in the Year 1665, in which, a certain Man, three Months before the beginning of the Plague, was taken with a Swelling in his Groin; which he had likewise as a Forerunner to several other Plagues. And Fabritius Hildanus relates a Story no less remarkable of himself; who, when, in his Youth, he had had the Plague, could never pass any House infected with it without a sensible Pain in that Part. To which may be added, a third Instance from that Curious Physician, who observed the various Phaenomena of Distempers at the Siege of Breda, and says, Annotandum hic meritò Naturae Facultatem ad Pestis Praeservationem Momenti esse maximi: Observavi in meipso contaminatos invisente statim inguina olere vel axillas; afficiebatur aliquando Caput, noctu inde Sudor, & secessus tres quatuorve; hoc & aliis accidit, qui fideliter mihi retulerunt. And these Testimonies I am rather inclined to depend on, because delivered by Men of Judgement and Credit. Another Suspicion which I am about to relate, A Third. is, That the Laws of Nature, which contribute to the producing of several Phaenomena, are not only of larger Extent than what we are used to imagine; but likewise concur to the Production of a greater Variety of Effects: For not to spend much time in observing, That several Industrious Astrologers and Geographers, have, instead of Physical, given us Mathematical Hypotheses; having taken pains to describe the Situations and Motions of the fixed Stars and Planets; and likewise, that they have been Industrious in discovering the four little Planets, which move about Jupiter; as also the little Moon, which runs about Saturn, as well as several Phaenomena relating to Comets, without considering the Frame and Constitution of those Bodies, which compose our Globe; I conceive it not impossible to make it out, That there is a Commerce betwixt them and our Globe; as well as several Laws or Customs of Nature even in our own Globe not taken notice of by Scholastical and Mathematical Writers. The Fourth. And I am, not without Reason, induced to suspect, That this Globe of ours hath undergone several considerable Changes, not only in several Countries, but the internal Parts of it; That which is called the Mariner's Compass, having been, in several Places, observed to vary considerably, in its Declension from the true North Pole; as for Instance, about London in the Year 1580 it declined eleven Degrees; in 1612 about six; and in the Year 1633 about four Degrees. And I have myself, at one time, observed little or no Declension, whereas at another I observed it to decline near half a Degree. And I am informed by one who often observed the Variation of the Compass at the Cape of good Hope, that, when he was a young Man, he observed it to decline two Degrees Westward; whereas of late, he found the Variation to be six Degrees and about forty eight Minutes; so that, by his Observation, it had varied little less than five Degrees, in the times he hath sailed past that Place. From whence we may have Reason to think, That there are certain Agents very powerful, tho' not to be taken notice of, which may work several, and very considerable Changes, even in the Terrestrial Globe itself; which whether regulated by any certain Laws of Nature, we know not. And besides these, there are several other unheeded Phaenomena, which we have troubled ourselves very little to consider about; as the different Weight of our Atmosphere, and the Causes of that Difference; we having only noted that they proceed from some subterraneal Effluviums mixed with the Air; but what other Effects those Effluviums may have upon other Bodies hath been scarce discovered. Considerable Variations in the Temper of Climates. And it is not a little strange, what Monsieur de Rochfort relates, concerning those Hurricanes observed in the American Islands; for, whereas, for a long time, they were observed to come but once in seven Years; yet in a short time they grew so frequent, as to return two or three times in the same Year. And I have been informed by an Ingenious Gentleman, that, having lived in New England, he observed a considerable Alteration in the Temper of that Climate; it being much less cold and more temperate than formerly. And Mr. W. Wood, in his Prospect of New England, takes notice of no inconsiderable Alteration; who says, That since the English Inhabitants settled there, the Showers of Rain are much more moderate, though more frequent. An Observation concerning Manna. And the Learned Magnenus observes, in his Tract the Manna, That about three hundred Years ago there was no Manna to be found in Cenotria; and it is not above two Ages since Manna hath been found in Calabria, a Country so famous for it. And the Ingenious French Writer in his History des Isles Antilles Lib. 4. Cap. 6. says, That if the Juice of a Fruit called Acajou, falls upon a Cloth, it presently stains it red, which continues till the Tree bears Flowers again; which Phaenomenon will be the more to our Purpose, if it may be doubted, whether it proceeded from the Temper of the Air or Length of Time. Another Suspicion But besides these Phaenomena, when I observe the exact time, that the ebbing and flowing of the Sea keeps; and how exactly coincident with the New and Full Moon Spring-Tides happen; as also what vast Spring-Tides are constantly observed every Equinox; together with those various Phaenomena, which may be observed in Sea-Water, which, in some Places and upon the blowing of some Winds, appears to be luminous, whereas other Parts are, at the same time, neither luminous, nor in the least affected, so as to become luminous by those Winds at any other time; I am very apt to believe, That these Phaenomena proceeded from some Cosmical Law of Nature; or that the Planetary Vortex was not a little concerned in producing these Effects. Another Suspicion. And I am not unapt to believe, but that all those Distempers, which are either Endemic or Epidemic, proceed from a certain Influence, which those Globes which move about us, may have, together with some Terrestrial Effluvia, which are different in several Countries. But not to engage in so fertile a Discourse as the Phaenomena, which every particular Region affords; I shall only add two Suspicions more, which may be further Instances of the Established Laws and Customs of Nature. A very considerable Phaenomenon relating to the Sun. And first, it is a Question, whether those Planets, which move about our Globe, keep such constant Bounds in their Motion, and move in such Lines as Astrologers teach they do. And if we consider the vast variety of Bodies, contained in and about our Globe, it can scarce be imagined, that Nature should always keep to one constant and regular way of Acting, but that in several Particulars, she must deviate and operate variously; for not to mention, that Astronomers have observed, even Natural Days to vary in Length; and have disputed much concerning the Anomalic assigned to the Motion of the Sun's Apogeum; The Sun itself hath been sometimes observed, to be even obscured by opacous Matter, as in Caesar's time, and at the beginning of Augustus his Government; when the Sun was for near a whole Year obscured. To which we may subjoin the Number, Duration, and Vastness as well as Motion of some Comets. And I am informed, that in the Northern Hemisphere, in that part of the Galaxy, which is not to be discerned by us, there are certain black, and near the Northern Pole, white Clouds, which move along with the Galaxy in twenty four hours; and these may be discerned by those that sail 18 Degrees South Latitude; but I shall not insist upon these as Arguments, since I suspect those black Clouds to be nothing but the Azure Sky appearing through the Galaxy, and those white ones, to be only Constellations, like those of the Galaxy or the Belt of Orion. Nature may not always be exact in her Laws. But having hinted, that Nature may not always be exactly regular in the Motion of Planets, etc. I shall here intimate, that sometimes we may think, those Motions which are Periodical and return at set times, irregular; because we live not long enough to observe the frequent Returns of such Changes, as we usually esteem Prodigies in Nature; for it would as much be thought strange, to see Trees blossom, and Fruit in the Summer, to a Man that lived but one Year, as several other Phaenomena are strange to us, who have not lived long enough to have observed such Phaenomena in their Periodical Turns before: So before the different Appearances of Saturn had often been observed, they were thought Prodigies. But it is most remarkable, that several Stars have Periodically appeared and disappeared several times in the same Place, as hath been observed in the Girdle of Andromeda, and about the Swans Breast, and another amongst the fixed Stars in the Whale's Neck. These I say are most remarkable, because they not only confirm what I have been saying of the Periodical Appearances of some Phaenomena; but invalidate the Philosophical Systems of some, who allow of no Vortices beyond the concave Surfaces of the Firmament: Vortices beyond the Concave Surfaces of the Firmament. But if rather than to allow of Vortices beyond the Surface of the Firmament, we would imagine the Stars, which appear and disappear, to have dark and light Hemispheres, which Periodically turn towards our Globe; it will still be an Argument to question the Uniformity of the Motions of some of the Globes of the Universe; since at so vast a Distance, such considerable Alterations are observable. But to conclude this Chapter; It may be a question, whether such prodigious Changes as are sometimus observed, may not by being frequently repeated, become a Custom, and have a Right to be reckoned amongst the Laws of Nature. CHAP. III. Of the Temperature of Subterraneal Regions as to Heat and Cold. FOr some Reasons, having been unable to examine into the Temper of the Air in subterraneal Regions myself, I shall rather give such an Account of it, as I have received from several Persons. The Temper of the Air in Groves. And first, I shall relate a Story of the Temper of the Air observed by a Chemist, who purposely traveled into Hungary, which was the following: That going down into a Grove, at the first Entrance of it, he perceived the Air sensibly warm; but presently after for a quarter of an hour in his descent, he felt it considerably cold; which cold Region being passed, he began to perceive it sensibly warmer, and the lower he descended the hotter it grew; so that, in the lower Veins, it was hotter than the Air above ground is usually in Summer: And this Relation was confirmed by a like Observation made by a Physician, who told me, that in a Mine, whose descent did not much exceed an hundred Fathom, the cold Region was extended near to the bottom of it. And this Relation is agreeable with what Morinus affirms, viz. That the Cold Region, in an Hungarian Mine, which he visited, was extended 80 Fathom, after which the Heat sensibly increased, the lower he descended; and the same Author affirms, that besides the different Tempers of those Regions, there is likewise observed, a different Degree of Heat, in the hot Region, correspondent to the different Seasons of the Year, viz. Winter and Summer. The Temperature of Subterraneal Regions considered under certain Propositions. Prop. I. These things premised in General, I shall now proceed to consider the Particular Regions of the Earth in the four following Propositions. PROPOSITION I. The Bounds as well as Temperature of the first Region are very different. The Reason of both Parts of which Proposition are plain; since the Sun Beams must not only penetrate deeper in the Summer than the Winter; but also, because the solidity or porousness of several Parts of the Earth may dispose the Soil to Heat or Coldness. But to proceed, it is remarkable, that the uppermost Region is much more temperate, because both the violent Impressions of Sun Beams, and rugged Winds, are kept off by the sides of those Subterraneal Cavities. And that the Power of the Sun Beams is much weakened by those sides, is plain; since, by such like means, the Heat of the Sun may be so broken, as to preserve Ice from thawing all Summer; and not only so, but if those subterraneal Cavities be sufficiently guarded with a Cover of Brick, well clayed over; and be, by that means, preserved from any Intercourse with the External Air, it may be preserved without digging deep into the Ground, as is observed in the South Part of France; so that, though the Coldness of Subterraneal Cavities may conduce, yet it is not altogether requisite to preserve Ice from a Thaw. But the subterraneal Regions are not only preserved from excessive Heat, by preventing the Intercourse of the Internal and the External Air, but may be considerably lessened in such Cavities as are considerably exposed to the open Air: as I myself have observed in an Iron Mine not above twelve foot deep. As as it is to be observed, that this cold Region of the Air is not apt to be influenced by external Heat in the Summer, so neither is the hot Region subject to be altered much by the external Cold in Winter; which appears from the smoking of some Springs in Winter, which are supplied with Water, which had run a considerable depth in the ground, or passed through some Earth that was fitly disposed to warm it in its Passage. But further, that Winter's Cold is much more disposed to influence the superficial Region of the Earth than the hot one which lies under it, appears from Reason itself, and may be further confirmed by observing, that even Water in freezing los●● its Fluidity, and puts on the Form of Ice, first in those Parts which are most contiguous to the Air, and subject to the Influence of External Cold: And it is observed, not only in England, but also in Russia, that if Wine or Beer be kept in a Cellar well roofed over, and about twelve foot deep, it may be preserved from freezing, notwithstanding the Violence of external Cold; where it is to be observed, that the Warmth of those Vaults, does not only depend on the Exclusion of External Air, but also on the Steams of those fermenting Liquors, together with some subterraneal Steams, which are gathered there, and hindered from flying away. PROPOSITION II. Prop. II. But to proceed to the Second Proposition, which may be comprised in the two following Members; As first, Member the first. That the Temper of the Second Region of the Earth seems to be colder than that above or that below it. This is both confirmed by Observations already cited, and also by Reason; by the latter, because the Earth, being a Body compounded of Parts less agitated than those about our Sensory, they must consequently cause a Sensation of Cold; Why the Middle Region is coldest. and why that Region should have its Parts less agitated, than those about it is plain, because it lies remoter both from the Influence of External, as well as Subterraneal Heat. But here it is to be noted, That though I say, the middle Region is coldest, yet I would only be understood to mean a comparative Coldness; for I by no means think that Region to be possessed with the most intense Degrees of Coldness, since neither Ice or Snow have been ever observed to be found in it: And though it be comparatively colder than those Regions about it; yet, that it is not the coldest may be hence argued, because it is observed in the Summer, that the Exhalations which steam from the middle Region are sensibly warm at the Orifice of the Grove; which they could not be, were the middle Region through which they passed extremely cold. The second Member of the second Proposition. But to pass to the second Member of this second Proposition; It is observed, That in several Places, which may be referred to this middle Region, the Temperature of the Air is different at the same Seasons of the Year. Which is evident both from Reason and Experience. And first, from Experience it hath been learned, by those who have often been in those Hungarian Mines, as well as some here in England. And indeed if we consider the different Heat in different Climates; but more peculiarly the Difference in Soils, it will not be less consonant to Reason; for the Soil may be more or less porous and compact; The different Temper of Subterraneal Regions may be varied by the Soyl. and may have different Substances mixed with it, or run through it, which may alter the Temper of it; for there is not always that Regular Order in Nature, which is in our Thoughts of her; since Salts, Marchasites and Minerals are dispersed through the middle as well as the lower Regions of the Earth; and may, by impregnating those Fluids which run through the Earth, cause different Refrigerating Effluvia to affect various Parts of the same Region; as if, in one Place, it be impregnated with Nitre, and in another with Marchasitical Earth; the Coldness of the former must render that Part of the Region the colder of the two. Besides, the Temper of them may differ upon the account of the Soil itself, which varies according to the several Degrees of its Maturity; so that for these Reasons, the Temper of Effluvia may be different in the same Place at one time from what they are at another in the same Place; not to mention those Differences which it may undergo by several other Accidents, and the Subterraneal Effluvia, which ascend more or less from the lower Regions. And before I leave this Proposition, it may be necessary to advertise, That the different Degrees of Heat or Cold, in the several Regions of the Earth, are not easily discovered by those Thermoscopes, which are usually made use of, to distinguish such Differences; because the Pillar of Air, which presses upon the Liquor may differ in its Pressure, according to the Length of it; it being longer, and consequently heavier, the lower it descends. But to pass to the Third Region comprised in the following Proposition, Prop. III. viz. That the Temper of the Third Region is warm, which Warmth varies in several places. That it is Warm, and that that Heat varies in several places, I think is sufficiently attested, by the several Persons that have gone down into those Mines; but as for the Causes of it, those are not so easily discovered: for I am not a little inclined to suspect, That considering the Closeness of those Cavities in which they work, the Effluviums of their own Bodies, and of the Metal they work in, may in some measure contribute to it. The effects of Subterraneal Fires. But to pass by this Suspicion, I shall rather briefly intimate, That I conceive the Earth to be stocked with store of Subterraneal Fires; and that several Calorifick Qualities, being carried up through Clefts and Veins in the Earth, cause a Sensible Heat to be diffused through the whole. And that there are such Steams, appears manifestly from those Damps, which are often observed in Groves; not only in England, but Germany, Bohemia, Hungary, etc. which are sometimes so Bituminous and Sulphureous in Smell, as to be apt to take actual Fire. But one thing I must intimate here, which is, That tho' I am induced to believe, for some Reasons, this Argument valid; yet, I am not without a Suspicion, that notwithstanding the Aptness which these Exhalations have to take Flame; yet, even several cold Steams may rise from the lower Parts of the Earth, which may acquire Heat in the Upper Regions; for we see, that several Substances, which are apt enough to take Flame, have not the least sensible Heat in their Parts before; nay, are so far from that, that Salt-Petre, which is so apt to flame, will, by being dissolved in Water, add a considerable Degree of Coldness to it: And the like may be observed in Spirit of Wine, whose Spirit, tho' easily inflammable, affects not the Touch with the least Heat, if raised in the Form of a Vapour. But that which inclines me to be of the Opinion just now mentioned, is, That not only Morinus, but several others have observed, the Exhalations of Mines considerably hot in Summer time. And the Experienced Agricola hath oserved, That the Mineral Steams which pervade the Earth, are so powerful, as not to permit a Horefrost to lie upon the Ground which they lie under; and the like hath been observed upon Coal-Mines: And I remember, that an Acquaintance of mine showed me a piece of Land, which was so powerfully penetrated with warm Effluvia, that Snow would not lie upon it above two Days, were the Wether never so cold, which hath been confirmed by frequent Observations; except where Layers of Rock, or some other Stony Concretes, obstructed the Passage of those Mineral Steams. To which may be added, That the Steams near Gold-Mines are so copious in Hungary, as to give the Leavs of the Trees a Golden-Colour. But notwithstaning these Instances, I am apt to doubt, that there are several Parts of the third Region, which by reason of their Remoteness from such Subterraneal Fires, have not that Heat. But since these things are but uncertainly guessed at, none having so great Curiosity, as to be at the Charges to dig deep enough without prospect of Gain, I shall rather proceed to consider, That, Whence the Unusual Heat in some Mines proceeds. besides the foremention'd Causes, there is in some Mines such a degree of Heat, as cannot be accounted for without another Cause; the Incalescence being so great, as not to be produced without the Concourse of some other Mineral-Steams, or Water to work upon, and promote the mutual Actions and Operations of the Volatile and Active Parts of those Mines. And that such Incalescenses may be produced in the Bowels of the Earth, I have elsewhere observed: And further, That Immature Minerals, such as Marchasites, whose Parts are impregnated with Vitriol and Sulphureous Parts, may, by reason of their Aptness to be dissolved, be able to cause such Effects, we may be induced to believe, because Vitriol hath not only been found in several Mines in Hungary; but likewise such Strong and Corrosive Effluviums, as were very offensive to Respiration, and in a little time fatal to those that ventured to work in them. And there is one thing further Remarkable, That several pieces of Vitriol, which were found in the Bottom of some of those Mines, of a soft Consistence, presently, when brought up and exposed to the open Air, grew hard, retaining several Golden Streaks in it. But there is one thing here to be noted, which is, That, in Groves which are very deep, the Air is so unfit for Respiration, as to want a frequent Ventilation; so that the Miners are wont to sink an Air-Shaft, as they term it, some Paces off the Grove, that the Air passing from the Grove to that, by a short of Channel, or Ventiduct, (which Agricola lib. v. and vi. de re Metallica, calls Cuniculus) might keep the Internal Air in such a Temper, as to make it fit to breathe in; tho' the Mines were 200 Yards deep. And Agricola, in his Book de re Metallica, gives further the following Account of the Course of the Air in these Cuniculi, or Air-Shafts, in these Words: Aer autem exterior se suâ sponte fundit in Cava Terrae, atque cum per ea penetrare potest, rursus evolat foras. Sed diversa Ratione hoc fieri solet; Etenim Vernis & Aestivis diebus in altiorem puteum influit & per Cuniculum vel Fossam latentem permeat, ac ex humiliori effluit similiter iisdem diebus in altiorem Cuniculum infunditur, ac interjecto puteo defluit in humiliorem Cuniculum atque ex eo emanat. Autumnali & Hyberno Tempore contra in Cuniculum vel Puteum humiliorem intrat & ex altiori exit: Verum ea fluxionum Aeris Mutatio in temperatis Regionibus fit in initio Veris, ac in fine Autumni; in frigidis autem, in fine Veris, & in initio Autumni: To which he adds, Sed Aer utroque tempore antequam cursum suum illum consuetum constanter teneat, plerumque quatuordecem dierum spatio crebras habet mutationes, modo in altiorem Puteum vel Cuniculum influens, modo in humiliorem. And these things may give us some Reason to believe, That there are in the Earth several Periodical Changes in the Temperature of those Regions, which deserve our Consideration. But having several times enquired about these things, I am informed that the Air generally goes in the same way, both Winter and Summer, entering the Air-Shaft, and coming out of the Perpendicular Grove. But to conclude this Chapter: From what hath been said, it may appear, That tho' in some Mines, the Earth seems to be distinguished into three Rgions, yet generally the Temperature of the whole is various and uncertain: And much more uncertain is it, what is the Constitution of the Central Parts of it; and whether that be divided into Distinct Regions, or what is the State and Texture as well as Consistency of its Parts, we must be content to be ignorant of; since one of the deepest Mines we have heard of, being mentioned by Agricola, in his Book called Bormannus; Cap. 12. was at Cotteberg, which exceeded not 500 Fathom; and if, according to Gassendus, the Semi-diameter of our Globe be 4177 Italian Miles, what a Superficial Knowledge must we have of it, who have not been able to make our Observations above 500 Fathom; and that too, in but a small Part of its Orb. CHAP. IU. Of the Temperature of the Submarine Regions, as to Heat and Cold. THE following Chapter relating to the Temper of Submarine Regions, I would be supposed to mean, by that Term, not such as are beneath the whole Ocean, but only such as are beneath its Superficies; concerning which, I shall not relate what follows, as upon my own Observation, but only as received by Information from others, who have dived into them. Submarine Regions two. And First, I shall only assign to this Element two Regions; the One bounded by the utmost Penetrations of the Rays of the Sun, and other Calorifick Causes; the other extending itself to the utmost Depth of the Water. The Temperature of the Uppermost. According to which Division it will follow, that the Upper Region must vary in its Extent; according to the Difference of the Climate, and the Heat of the Sun, (supposing the Warmth of it not to proceed from Subterraneal Effluvia;) and not only in the Extent, but the Temperature of that Region; which may not only be varied by the Influence of the Sun, but also, by the different Nature of the Soil about the Shores, being either Nitrous, or Marchasitical; as also by the Shallowness of the Water, which may contribute to the Warmness of it, the Rays of the Sun being refracted by the Subjacent Sands. To which Causes may be added the Influence of Subterraneal Fire: An Observation favouring which, hath been made by Monsieur de Ponts, in his Voyage to New France; in the way to which he observed, That in one Place the Water was very warm, as well as the Wine, which lay in the Boat, tho' there was no sensible Alteration in the Air; and that this continued for three Days; whereas, on the 21rst of the same Month, it was for 2 or 3 Days observed to be as cold. The Temperature of the Lower Region. These things in short being premised, concerning the Upper Region, I shall now proceed to the Lower, which is Cold; the Parts of Water being in a less violent Agitation than our Sensory: And that the Lower Region is sensibly cold, is not only consonant to Reason, but also confirmed by the Observation of those, who have dived a considerable Depth, not only in the Northern Seas, in Africa and America; but it is also further evinced, by what is commonly practised at Sea, viz. to let down Bottles of Wine into the Sea all Night; which, by being immersed in the Water, will acquire a considerable Degree of Coldness. And I am also informed by an Observing Traveller, that having let down about 400 Fathom of Line, with about 30 pound of Lead at it, thirty five Degrees North Latitude beyond the Line; the Lead, when drawn up, was as cold as Ice. From which Instances it appears, that the Air and Water so far agree, that the Parts of them being put into Motion, by External Causes, they acquired each a considerable Degree of Warmth; but, being removed and separate from those Causes, put on a contrary Quality; so that the Air and Water seem chief in this respect to differ, viz. in their inverted Order. But further: From what hath been delivered, it appears, That tho' the Submarine Regions be sensibly colder, the nearer the Bottom; yet their coldest Region does not, by any of the aforementioned Phaenomena, appear to be the Summum Frigidum; for tho' I have several times frozen Salt-water, yet it does not appear, that there is the least Ice generated in the Bottom of the Sea; since from the Bottom of the great Ocean 35 Degrees South Latitude, Grey Sand hath been brought up, where the Water was no less than two hundred and twenty Fathom deep: But yet there is one Caution to be added, which makes this Observation the less to be relied on; which is, That one Reason why no Ice is to be found in the Bottom of the Sea, may be the Unaptitude of Salt-Water, more than of Fresh, to be congealed; it requiring a much greater degree of Cold to freeze Salt-Water, than Fresh. CHAP. V Relations about the Bottom of the Sea. The Bottom of the Sea very Rough and Unequal. THAT the Bottom of the Sea is usually Salt and Cold, is a very common Observation; but being desirous to be more nicely informed, about what occurs in that Region; I have been told by several, who have in long Voyages, fathomed in several places, that the Bottom of the Sea is rough, with considerable Inequalities, and Precipices; so that in a small Space a little Depth of the Sea hath increased to a hundred Fathom, and decreased as suddenly: There being likewise found several other Inequalities and Hills, observed in Places about 30 or 20 Fathom deep; where a Line of 16 Fathom, would upon the next Cast require 35 or 40 to reach to the Bottom of the Sea; and the like Observations I have received from several Experienced Mariners: Amongst which, I transcribed the following Account, from some Notes left in England, by one who had made a Voyage to the East-Indies: The Account was this. February 12. After our Observation, seeing the Ground under us, we heaved the Lead, and had but 19 Fathom Rocky Ground, then haled by N.N. E. the Wind at N.W. and found our Water to shoal from 19 to 10 and 8 Fathom, hard Coral Ground; then suddenly deepned again from 8 to 20 and 22 Fathom Sandy Ground; and then suddenly saw Rocks under us, where we had but 7 Fathom, and the next Cast 14 Fathom again; and so having run N. N. E. from 6 in the Morning, till 12 at Noon, about 19 Mileswe deepned our Water from 16 to 25, and the next Cast no Ground with 35 Fathom of Line. The Gravitation of the Water. But besides the Inequalities to be taken Notice of at the Bottom of the Sea, there are several other Things to be observed; amongst which the Gravitation of the Water, is remarkable; and tho' it be disputed amongst Philosophers, whether there be such Gravitation or not; yet that there is, appears from several Experiments. And First, If a Glass-Cylinder, with one End open, be immerged in a Glass-Vessel, it may be observed, That as the Cylinder is pressed lower, the Air by the Pressure of the Water, will be squeezed higher and higher, the water rising gradually below it in the Cylinder. And the like hath been observed by several Persons, who have dived in a Diving-Bell, not only in the Northern Sea, but upon the Coast of Africa; where as the Bell went deeper and deeper, the Air became more compressed, and the Water accordingly risen higher and higher in the Bell. And sometimes the Pressure hath been observed to be so powerful, that I have been informed by one who let down a Glass-Vial into the Sea, near the Straight's Mouth, that, having let it sink about 40 Fathom, it was burst in pieces, by the outward Pressure of the Water; to which he added, That, having let down an Aeolipile of Metal, and sunk it about 60 Fathom, he observed when it was drawn up, that the sides were in several places bruised and compressed by the violent Pressure of the Water. The Bottom of the Sea not disturbed in Storms Another thing observable in the Bottom of the Sea, is, That tho' the Violence of Storms may disturb it, where it is shallow; yet where it is considerably deep, the nearer the Bottom, the more calm and undisturbed it is. And this hath been confirmed by the Observations of Divers, who have taken Notice, That tho' the Waves were six or seven foot high, yet, at fifteen Fathom deep, the Water was very little disturbed, only the Mud was raised, which made the Water dark; and what is very remarkable, is, that the Person that dived informed me, that having stayed a considerable depth for some time, he found, when he came up again, a Tempestuous Storm, which had risen when he was in the Water, without being taken Notice of by him below. And the like hath been observed, near the shore of Manar, in the East-Indies, where they dive for Coral, in a Sea, that lies betwixt the Island of Ceylon, and the Cape of Comori, which is usually very much disturbed; inasmuch as it lies near the Indian Ocean, and the Gulf of Bengala, formerly called Sinus Gangeticus. And it hath elsewhere been observed, That, in considerable Storms, the Seas have not been disturbed over the Depth of 4 Fathom. The Water at the Bottom of the Sea almost stagnates. And to these Observations I might add, had I sufficient Evidence to build upon, That, having enquired, whether upon Ebbing and Flowing of Tides, the Motion of the Water was continued to the Bottom; I have been told by some, that it does almost stagnate, and by others, that the Current of the Water above, is different from the Tendency of that below. But not to rely upon these Relations, I have been informed, by a Person who made his Observations beyond the Cape of Good Hope, in the Southern Sea, that, having let down his Plummet, about an hundred Fathom, he found, that the Plummet being suspended in the standing Water, made the Boat turn to the Tide, as if it lay at Anchor. And that there is such a Stagnation of Water at the Bottom of the Sea, hath been likewise confirmed to me, by Observations made near the Coral Fishery, in the East-Indies. CHAP. VI Further Relations about the Bottom of the Sea. THAT the Air, is not only necessary to the Preservation of Animals, but also promotes Vegetation, and the Growth of Plants, I have elsewhere observed; but since several Trees and Plants are observed to grow under Water, I shall further observe what Informations I have received concerning them. Observations relating to Coral. And First, To what hath elsewhere been delivered concerning the Growth of Coral under Water, I shall add, That I am informed by one, that saw it near Algiers, that Coral, when first taken up, is not only soft and flexible, but very pale; yet when the Bark is taken off, and it is exposed to the Air, it's Natural Redness presently appears: To which he added, That having broke several Pieces, he found it much paler within than on the outside; and that there were several black Knobs on the extreme Parts of the Twigs; the place from whence this Coral was taken, being about nine or ten Fathom deep. And I have been further informed by one that sailed to the East-Indies, that upon a certain sort of Coral he hath observed, certain round Berries of a very pleasant Colour. Trees under Water. To these Relations I shall add, That Divers have not only observed Trees to grow under Water, near Manar, which bore Leaves like those of a Laurel, but that not far from the Coast of Mosambique, in Africa, several Trees are observed to grow under Water, whose Fruit and Leaves are like those of the Tree in America, which bears a Fruit called Acayu. But an Observation more Valuable, is concerning the Maldavian Nut, called Coco, which by experienced Divers, are found to be the Fruit of a Tree, which grows at the Bottom of the Sea, which are either gathered by the Divers, or torn off by the violent Agitation of the Water: In which Fruit it was observed, that, whilst it was under Water, it was very soft; but when it had been exposed a considerable time to the Air, it became very hard. CHAP. VII. Observations and Experiments about the Saltness of the SEA. The Invalidity of the Cause assigned by the Peripatetics. THE Saltness of the Sea, by several Peripatetics, hath been judged to proceed from the Influence of the Beams of the Sun upon the Water; but with what little reason may easily appear from those standing Lakes and Ponds, whose Water, notwithstanding the Influence of the Sun, continues fresh: And that it neither proceeds from the Influence of the Sun, nor any other external Heat may be argued, since though some fresh Water be drawn off by Distillation, and consequently undergoes as great a Degree of Heat, as it can be supposed to do from the Sun Beams, it yields not so much Salt as is to be found in some Water, never exposed to such Heat; which Salt differs very little from Sea Salt, only that it is whiter, being more clear of its faeces, and free from a Mixture of earthy Parts. And though some allege in favour of Aristotle's Doctrine, That Scaliger affirms the Sea Water to be saltest in its upper Region; yet it will appear, by comparing the Saltness of the superficial Parts of the Sea with the bottom, that the Observation was ill made, and does not generally hold; neither will it favour his Doctrine, should it be alleged, that Sea Salt dissolved in Water, otherwise than common Salt christalizes at the Top of the evaporated Solution; for considering how much Salt Water must be impregnated with; and that the Quantity of Salt in Sea Water hath been observed by a Dutch Geographer to be only as One to Forty; The proportion of Salt to Water. it's Disposition to crystallize can be no Argument of the swimming of Sea-Salt more on the top of the Water than the other Region. But though I differ in this Point from the Peripatetic Philosophers; yet I do not believe, on the contrary, with some, that the Gravity of Salt makes them sink the more to the bottom; since the intestine Agitation of the Parts of the Water continually shifting Places must consequently carry it along with them; which Consideration joined with another, which is, that I have not usually observed, Metalline Tinctures stronger at the top than bottom, might perhaps give a suspicion to some, that the present Argument is less cogent, notwithstanding the specific Gravity, betwixt Metals and their Menstruums does much exceed that betwixt Salt and Water. But further in behalf of the Peripatetic Doctrine, it is urged out of Linscotten, that, at Goa in Portugal, it is usual for their Slaves to dive, and fetch fresh Water from the bottom of the Sea; but tho' this Matter of Fact were true, yet no general Rules could be drawn thence; because Experience tells us, that in other Places it is contrary. Besides it might be probably guessed, that, Springs in the Bottom of the Sea. were it true, that fresh Water might rise by certain Springs covered over with Sea Water, as well as that several Springs in other Places should be under Water upon the flowing of the Sea: And that there may be such Springs is so far probable, that the curious Hungarian Governor de admirandis Hungariae Aquis, says, That in the River Vagus, near the Fortress Galgotium, Veins of hot Water rise up in the very bottom of the Water; his Words are these, Neque in Ripa tantum eruuntur calidae, sed etiam intra amnem, si fundum ejus pedibus suffodias; calent autem immodicè, etc. And the like hath been observed upon the Neapolitan Coast. But not to urge these Relations, I shall intimate briefly, That an ingenious Acquaintance of mine, who lives in that City, hath informed me, that that fresh Water is not fetched so deep as to be suspected to rise from such Springs; but that it is rather the fresh Water which runs into the Sea from a River not far off, before it is mixed with the Salt Water; which Conjecture I the rather believe, because near Mouths of Rivers it hath elsewhere been observed, that fresh Water hath for some time floated together, without being perfectly mixed with the other Stream. And as for Scaliger's Opinion, it might be urged against it, that by a Vessel so artificially contrived, that it might be opened at the bottom of the Sea to take in Water, the Water drawn up hath been found to be Salt. But since it may be urged against this, that the Salt Water being heavier than the fresh, as it was drawing up might be mixed with it, by pressing into the Vessel; I shall add Instances not liable to such Objections; for it hath been observed, not only at the Cape of Comori, but elsewhere, by Divers, that the Water is as Salt at the bottom as at the top; and I am informed, that Divers have not only under the Torrid Zone observed the Water exceeding Salt, but have brought several Lumps of Salt from the bottom with the Sea: And the like Saltness of the bottom of the Sea hath been discovered near the straits of Gibralter's Mouth: And further, that I might not only be sure, that the Sea was thus Salt at the bottom, I procured two Quarts of Sea Water, the one taken up at the bottom of the Sea and another at the top; in which, though there was some Difference in Colour; yet being Hydrostatically tried, there was no sensible difference in the specific Gravity of them. But to make out what I have before intimated, viz. That the Freshness of the Water in the bottom of the Sea near Goa might be produced by the Rise of some Springs under Water; though it may be objected, that the specific Gravity of the Salt Water, would in some measure obstruct the Rising of fresh Water: Yet this Objection will easily be answered, if we consider, that according to what we have delivered in our Hydrostatical Paradoxes, and also what Stevinus hath observed, let the Quantity of Water be never so great, no more can resist the Rising of such Springs, but that Pillar of Water which lies over them in a perpendicular Line; and if the Spring takes its Rise from some high Place, so that the Weight of that Water which lies in the Vein, be heavier than the perpendicular Pillar of Sea Water, the Rising of it can by no means be hindered by the Pressure of that incumbent Water. But to explain and confirm this Paradox, I shall add, that having procured a long Glass Syphon, part of it being inverted so as to form a short Leg, I filled it with Claret, stopping the Orifice of the longer Leg with my Thumb, which Syphon, being immersed in Salt Water contained in a Glass Vessel, and the Orifice of the longer Leg being opened, the Claret, notwithstanding the Pressure of the Salt Water, presently risen up in it in the Form of Clouds, which lasted till the Liquor in the Pipe was brought to a just Aequilibrium with the incumbent Pillar of Salt Water. The Reason of the Saltness of the Sea. But to pass on to the Cause of the Saltness of Sea Water, I deny not what Gassendus and other Moderns teach; but grant, that the Saltness proceeds from a Solution of Salt in the Water; yet I am apt to suspect, that that Saltness is not only supplied by those Salt Rocks, which may be contiguous to, or near the Water; but that the Sea is in a great Measure supplied, by Salt washed away and carried into it, by Springs and Rain-water, which float into the Ocean. And I am the more confirmed in this Suspicion, because several Chemists have not only found Salt in some Waters; but have obtained a good Quantity of common Salt upon refining of Salt-Petre, which according to Sir Francis Bacon, is in most Soils, which are not spent in Vegetation, or washed and consumed by the Sun and Rain. But not to insist too long on these things, it is not only probable, That the Salts in the Earth, may, by this Means, contribute to the Saltness of the Sea; but that, from what hath been before delivered, such Salts may be communicated to it by latent Springs, not to be taken notice of or discerned by us. And further, That such Salt as abounds in the Earth, may supply the Sea with most of the Salt which is perceived to be in it; we are to render it further probable, to consider, That the Sea-Salt, and that, are agreeable in the main, with each other; since they have almost the same Shape and Taste, etc. the former of which will appear by Evaporation and Crystalizing them; and as for some small Difference to be perceived betwixt them, that may easily arise from those Bituminous and other, as well as Nitrous Bodies, which flow into the Sea, and which may be mixed with them, both by the internal Agitation of the Parts of the Water, as well as the outward Action of the Sun and Air. And that there is such Salt dissolved in Sea-Water, might be probable, if it were possible so to raise the fresh Water it was dissolved in, by Distillation, as to leave the Saline Parts behind; but not now to mention, that not only I, but the Judicious Sir John Haukins, in his Voyage to the East-Indies, have, by distilling of Salt-Water, obtained from it a wholesome fresh Water; I shall, without making a long Digression, proceed to answer an Objection, which is urged against what I have delivered, viz. That if the Springs acquired such a Saltness by running through the Earth, it would be discernible before they emptied themselves into the Ocean. To this I shall answer, That besides those fresh Springs which are visible to us, there may be several others which lie too deep for us to take Notice of: But here it may be requisite to take Notice, That I do not say, That the Saltness of the Sea wholly depends on such Supplies; but that they contribute to the Saltness of it. The Bitterness of Sea Water, whence. Having said so much of the Saltness of the Sea and its Causes; it may be now seasonable to observe, from whence proceeds that Bitterness remarkable in some, if not most Sea-Water; which, we conceive, may proceed, partly from the external Power of some Catholic Agent, and partly, from those Bituminous Bodies which are carried along with Spring-Water into the Sea, which hath been visibly apparent in the Island Barbadoes, where that which they call Barbadoes Tarr, hath been seen to flow from the Rock into the Sea; and to these Causes may concur some Subterraneal Exhalations and Effluvia, which I have elsewhere taken notice of to flow from and pervade the Earth. And as for those different Tastes which are perceived in the Sea at several Places, it is no less probable, that they proceed from other adventitious Bodies mixed and incorporated with the Sea-Water; for that the Sea-Salt which is dissolved in it, is not a simple Salt, but a compound, I have been induced to believe by a Salt which I obtained from it. And that some Catholic Agents may work Changes in the Saltness of the Sea, which it would not otherwise have, by a bare Solution of those adventitious Bodies that are mixed in it, I have Reason to believe, since I have found, That by keeping the Parts of Sea-Water in Agitation, by a continued digestive Heat, it hath considerably differed in Taste, from a bare Solution of Sea-Salt in Water. And for a further Confirmation, That the Saltness of the Sea is varied in several Places, I shall barely intimate those several Colours, different Qualities, and stupendious Multitudes of adventitious Corpuscles which are mixed with it. Agitation requisite to preserve Sea Water from stinking. But to proceed, amongst the various Observations to be made about Sea-Water, it is worth our Notice, That if it be kept from Agitation, it will in a short time stink; which I have not only observed, by keeping some of it in a Runlet for some time; but also, I am informed by one, who, in a Voyage, was for some days becalmed, that the Sea, for want of Agitation, stunk so much in twelve or fourteen days, that the Smell was almost intolerable; which continued till the Winds put the Water into Agitation. Which agrees with what Sir John Hawkins hath observed, who relates the following Story: Were it not for the Moving of the Sea, by the Force of Winds, Tides and Currents, it would corrupt all the World. The Experience of which I saw Anno 1590., lying with a Fleet about the Islands of Azores, almost Six Months, the greatest Part of the time we were becalmed, with which all the Sea became so replenished with several sorts of Jellies, and Forms of Serpents, Adders and Snakes, as seemed Wonderful; some green, some black, some yellow, some white, some of divers Colours, and many of them had Life, and some there were a Yard and a half, and some two Yards long; which had I not seen, I could hardly have believed; and hereof are Witnesses all the Company of the Ships, which were then present, so that hardly a Man could draw a Bucket of Water clear of some Corruption. In which Voyage toward the End thereof, many of every Ship fell sick of this Disease, and died apace, but that the speedy Passage into our own Country was a Remedy to the Crazed, and a Preservative for those that were not touched. The Saltness of the Sea differs. As for the different Degrees of the Saltness of the Sea, I shall deliver what I have been informed of, as briefly as I can. And First, It hath been observed, by one to whom I gave a Glass conveniently shaped to try the specific Gravity of the Water, that it grew heavier and heavier as he came nearer the Line, till within about thirty Degrees Latitude; from whence to Jamaica he observed no Alteration in the specific Gravity in the least. And in Confirmation of this I am likewise informed, by one, who for his own Satisfaction weighed the Water, both under the Aequinoctial and at Cape of good Hope, and found that the Weight of both was the same. To which may be added that it is commonly observed at Mosambique, one of the hottest Places in the World, that the Sea is so salt there, that it bears up the Ships a considerable Height out of the Water, more than in other Places; and that the Water may be much salter in one Place than another, by having more Salt dissolved in it, does not only appear from what hath been said, but also from what is frequently observed in the different Strength of Brine-Pits. But to pass from what I have learned by Information, to what I have observed myself concerning the Proportion of Salt to the Water it was dissolved in, which I have observed in Sea-Water, betwixt England and France. The Proportion of Salt in Sea-Water. The first Experiment I made to discover the Quantity of Salt was this, that having, in a Viol, weighed an equal Proportion of Sea-Water taken up at the Surface of the Sea, with common Water, the Weight of the former exceeded the latter of forty fifth Part; but these Liquors being more Hydrostatically tried, by weighing Sulphur in them, that which in the Sea-Water weighed ℥ ss + 10 ½ gr. in Sea-Water, fetched from the bottom, balanced the same Weight; but being weighed in common Water, it weighed ℥ ss + 15 ½ gr. so that the Sea-Water was a Fifty third Part heavier than the fresh; the Difference in which way of trying it, from what was observed in the former Trial, I could attribute to nothing, but some grosser Saline Parts mixed with the common Water, or some evaporated Parts of the Sea-Water. Another way we made use of to try the different specific Gravity of these Liquors, was, by Distillation ad Siccitatem in a digestive Furnace, in which a Pound Averdupoise Weight yielded ℥ ss 10 gr. of Salt; so that the Proportion of the Salt to the Water was as 30 and 12/100 to one, being near the Thirtieth Part. But suspecting that the Quantity of this Salt was much increased by imbibing Moisture from the Air, I caused it to be dried in a Crucible, and found it weighed ʒiij + ss, which is about a Thirty sixth Part. How so much a greater Quantity of Salt should be obtained by Distillation, is difficult to conjecture; yet I am apt to think, that it might proceed from some Parts of the Water detained from flying away, by being enclosed amongst the cubical Salts; and this I am apt to believe, First, Because I have elsewhere prepared a Salt, which would coagulate and embody itself with Water; and Secondly, Because I am told, That a Sort of Salt is brought from the Coast of Spain, which being here purified and dissolved, will yield a double Quantity. The Sea-Water salter sometimes than at others. Whether the Sea-Water may at some times be more impregnated with Saline Parts than at others, I conceive probable, if we consider the Supplies that it receives both from the Earth, which are carried to it along with Springs, and also, the sudden Additions it may receive from Subterraneal Exhalations; but these Observations being very nice, it most commonly requires other Measures than what hydrostatics afford; for it may be observed, That several volatile Salts which are of no considerable Weight above common Water, may be mixed with it without being perceived; so that one may easily be deceived in judging of the Saltness of the Sea altogether by hydrostatics; because, that which violently affects the Taste, may have but a small Influence in the Balance: To confirm which I shall add, That a Bubble of Glass, having Metal in it, weighed ʒiij ✚ 51 ¼ gr. in Spirit of Sal Armoniac, and but ʒiij ✚ 45 ¾ in common Water. But further, I weighed in the same Liquor an equal Proportion of Sea-Salt brought from the torrid Zone and Sal Armoniac, and found, that the Bulk of the former was, to an equal Proportion of that Liquor, as two and a quarter to one, whereas the Shall Armoniac was not above a hundredth Part, above one, and 7/10 to one, which is the more strange, because Part of the Composition of Sal Armoniac is Sea-Salt. But that I might be satisfied what was the greatest Degree of Saltness, that Water would be impregnated with; I shook a Lump of Salt in Water, till it would dissolve no more; and found that a Brine might be made so strong, that the Salt would be dissolved in five times its weight of Water. To conclude this Discourse, I shall add one thing which hath not been taken notice of by Hydrostaticians; which is, the weight of the Sea-Salt to its Bulk of Water, which I have found to be almost as two to one; and I likewise found, that a piece of Sal Gemm, which is more pure and weighty than Sea-Salt was to its Bulk of Water about as 2 2/8 to 1. CHAP. VIII. Memoirs for the Natural History of Mineral Waters. THE Use of Mineral Waters are so Universal, and the Methods which some Physicians take to try them so slight; that, tho' I am satisfied it is difficult, without Experience to Ascribe Virtues to them à priori, by Reason of the Great Variety of Minerals, which may impregnate them with Particles of various and very different Natures; I cannot but think, but that if we were furnished with a sufficient Number of Quaeres, and several Methods in order to a Discovery of them, more nice Trials might much Contribute to the clearing up of a Natural History of Mineral Waters; since by a competent number of Experiments it might be hoped, that the Nature of those Metalline Salts, with which Mineral Waters are Impregnated, might be discovered. Wherefore I have laid down such sorts of Experiments, that might be most easily tried, viz. chief Chemical Ones, which may be made at home, without the Inconveniencies of attending those Mineral Fountains from whence they spring. And because my Design is rather to improve Physic by the following Observations, than to entertain Speculative Naturalists; I have chief made it my Business in the following Papers, to consider those Waters called Acidulae, rather than the other termed Thermae, because the former are of more general Use. The danger of an ill use of Mineral Waters. But perhaps some may think that the Quares hereafter propounded may be too troublesome, and more than requisite; since the Use of Mineneral Waters are thought so innocent, as to be of no ill Consequence if Unsuccesful. To which it may be answered, that tho' when skilfully given, they do a great deal of good; yet they are as prejudicial if unskilfully prescribed; and therefore, since there cannot be too much Caution, we cannot be too inquisitive to inform ourselves of their Virtues; for there may be a great many hidden Qualities in them, and they may be impregnated with several Metalline Properties, which may not be discovered to the Eye or by common Trials. Besides, were such Experiments industriously prosecuted, they might help to discover several other Qualities in Mineral Waters, which are as yet unknown; for from the following Experiments it is evident, that the Earth, which abounds with Minerals of a Martial Nature, may be more apt to impregnate subterraneal Waters than we can otherwise imagine; for upon pouring of a Tincture of Galls filtrated through Cap-paper upon filings of Steel, The Effects of filings of Steel, in a Tincture of Galls. the Liquor in half an hour became Opacous, and almost as black as Ink: The like Phaenomena to which were exhibited by Steel in an Infusion of Brasil or Log-wood made in common Water. To which we may add, that several Waters have been discovered under ground of very different Tastes; some of which have been found to be corrosive, and others as harmless, being endowed with several Medicinal and Useful Qualities; and I am informed more particularly of one, which is a Mine of Coral in Devonshire about 360 foot deep, in which was found a Water very thick and red, yet cool and Diuretic, and not in the least nauseous to the Taste. CHAP. IX. Titles proposed for the Natural History of Mineral Waters, considered whilst in their proper Channel. Queries in order to a discovery of the Virtues of Mineral Waters. IN order to a natural History of Mineral Waters, they ought to be consider's in three different Capacities: First, as they are found in their natural Receptacles; Secondly, when drawn up for use; and thirdly, with Respect to their Effects on Human Bodies. To the first of which Heads the following Quaeres may be referred. 1. Within the Precinct of what Climate or Parallel, and in what degree of Latitude the Mineral Waters are to be found? 2. To what point these Waters lie open most in their Receptacles? 3. Whether the Ground in which they are found be a Plain, or how much it differs from a Plain? 4. If the Ground be upon an Ascent, how far they are from the botttom of that Ascent? 5. Whether a Recrementitious Substance adheres to Stones long contiguous to these Waters? 6. Whether subterraneal Fires be near such Waters, and what Phaenomena such exhibit? 7. Whether Brimstone or Salarmoniack, etc. be found about the Vents of such subterraneal Fires? 8. Whether instead of subterraneal Fires, there are other adjacent Aestuaries? and whether such be constant or intermitting? and if so, whether periodical or irregular? 9 Whether Mineral Fumes of particular colours or smells arise from such Aestuaries? 10. Of what Temper the neighbouring as well as the Soil they pass through is of? 11. Whether and of what Nature those Minerals are of which they pass through? 12. Whether the Mineral Waters be originally fresh, and derive their Virtues from the Soil they afterwards pass through? 13. Whether if it acquired its Virtues so, there were upon the Impregnation any Effervescence? or whether any such Effect succeeded its Mixture with another Liquor? 14. Whether there be a Spring of a contrary Nature near it, viz. as to Heat and Cold, as it is observed in France. 15. Whether an oily or bituminous inflammable Substance float in it? 16. Whether the Seasons of the Year, or Temperature of the Wether altars them? and what Qualities they lose or acquire by such? For after Rain I have observed such Waters incapable of turning a Tincture of Galls black: But as to its Medicinal Virtues, I have found that Rain after long Droughts, hath rather increased than diminished their Strength, by dissolving and diluting those Salts, which were fixed in the Earth for want of a Vehicle; but if the Waters be weak, and the Rain much, those Salts being the more diluted, render the Waters less Effectual. 17. Whether the Qualities of the Waters may be Chemically and Mechanically discovered? as also of what Colour and Weight, and with what Menstruums their Salts may be mixed? and likewise what Substances they will yield when exposed to different Degrees of Fire, and what other Chemical Trials those as well as the Caput Mortuum may undergo? CHAP. X. Containing Titles for the Natural History of Mineral Waters when drawn out of their Receptacles. A Continuation of Qeaeries. 1. WHether the Mineral Water proposed be actually Hot or Cold? From whence we may judge from what Depth those Water's rose? and whether they were impregnated with a Salt-Peter or Salarmoniack in their Ascent? And the several Degrees of Heat or Cold may be either tried by immerging a Thermoscope, or by trying whether they will Coagulate Oil of Aniseeds or melt Butter? 2. Of the specific Gravity; which, being compared with that of common Water, will show what Quantity of Mineral Substance the Water hath dissolved in it; and whether Metalline or more Volatile, as it is heavier or lighter; where we are to observe, that Mineral Waters are sometimes lighter than common Water; partly, because they are impregnated with Volatile Parts; and partly, because they are void of Saline Parts, which makes common Water something heavier. But to discover the different Weight of several Mineral Waters, I caused a Glass-Viol with a flat Bottom and a long Neck, three Inches long, to be blown, which was so light, as to weigh but ʒvi + 42 Grains; tho' it was capable of containing ℥ iij ss and 43 Grains of Water; which made it more proper for a Nice Balance, by which I found the following Mineral Waters to differ thus in Weight. Water's Ounces Drachms Grains Common 3 4 43 Common distilled 3 4 41 Acton 3 4 48 ½ Epsom 3 4 51 Dulwich 3 4 54 Staton 3 4 55 Barnet 3 4 52 North-Hall 3 4 50 German-Spaw 3 4 40 Tunbridge 3 4 38 Islington, from the Music-house. 3 4 36 Islington, from the Vault with Steps. 3 4 39 Islington, from the Cellar. 3 4 39 3. Of their different Degrees of Transparency or Opacity. 4. Whether without being exposed to the Air, it will afford a Pracipitate. By which Observation the different Soils through which they pass, will not only be discovered, but hence we may learn to distinguish such from the true Caput Mortuum of the Water. German Spa Water yielded a good Quantity of yellowish Ochre. N. B. the Water so tried must not be exposed to the Air, for if it be the Air will precipitate a considerable Quantity of Matter in most Waters. 5. What Microscopes can discover in Mineral Waters? N. B. those moving Corpuscles discernible in a Solution of Pepper, etc. in Water, are Animalcula, and not Portions of Inanimate Matter, which swim up and down such Liquors; which is apparent if those little Animals be touched with Spirit of Salt, for being killed by it, they move much more slowly. 6. Whether there be any variety of Colours in several Mineral Waters? 7. Of their different Odours. These are to be perceived at the Spring-Heads, where not only a Bituminous and Sulphurous Smell may easily be perceived; but I am informed, that there is a Mineral Spring in France which hath a manifest vinous Odour. 8. Concerning the different Tastes of Mineral Waters. 9 Whether taking it up, or keeping it stopped or unstopped? or whether freezing or thawing it will alter the Colour, Smell or Transparency of it? For tho' some Waters retain their Purgative Virtue a good while; yet, I have observed an Exhalation of some fugitive Parts from those which are lighter than Water, and abound with Spirituous Parts; so that, tho' they were carried but a little way from the Fountain, they presently lost their Power of turning a Tincture of Galls into a Purple, and instead of that, turned it red; and even the Strongest Waters, if kept unstopped, or not kept close, presently lose that Property. 10. Concerning the different Consistency of such Waters. 11. Whether they be more apt to Expansion and Condensation, or Heat and Coldness, than Common Water? 12. Whether they are apt to Putrify, and how soon, and what Phaenomena they afford? 13. What Alteration in Colours ensues the Mixture of Astringent Juices with them, as also their Mixture with several Juices of the Body. N. B. in trying of Mineral Waters, it is usual to make use of a Tincture of Galls, without considering the Alterations which may be made in the Trial, by an Uncertain Proportion of Galls: Wherefore I usually make use of a settled Proportion, as 5 Grains to an Ounce; tho' Mineral Waters may be tried with much more Expedition, and Certainty, by making use of the Powder itself, suspending about three Grains of Powder in an Ounce of the Waters; and I have found by Experience, that so small a Quantity as a Grain, hath given German Spaw-Water a deep Purple Colour. But it is not always necessary to make use of Galls in such Trials, since Rose Leaves, or the Flowers and Bark of Pomegranates, will have much the same Effect, affording a Cloudy and Blackish Tincture. And it is further to be noted, That I made it one Part of this Quaere, what Colours would be produced by a Mixture of Mineral Waters with Animal Juices; because I have observed the Root of the Tongue sometimes Blackish upon the taking of Large Doses. But to return to what I have observed concerning the trying of Mineral Waters, by an Infusion of Galls; I not only doubt whether all Martial Waters will turn a Tincture of Galls black, but whether all liquors which will, are to be esteemed Martial; for I have found that a Mineral of a Different Nature from Steel, would give it a Black Colour; and that a Liquor, which was a Preparation of Steel, would not; which induced me to think, that such a Tincture was rather the Effect of some Acid Fumes, which had worked on the Mars, with which those Mineral Waters are Impregnated. To which it may be added, That I have found, that if a Vitriolate Water be impregnated with Copper, instead of Iron, instead of turning a Tincture of Galls Blackish, it only would render it Muddy and Thick. And I had a sort of white Earth, which I found by Trials to be Lead, that would turn a Tincture of Galls Blackish, tho' it was altoger void of Martial Parts, and probably would have very bad Effects, if taken inwardly. To which I might further add, That a Tincture of Gold in Aqua fortis, likewise turned an Infusion of Galls Black. And those Observations I have been the willinger to lay down, because, tho' I would not be thought by them to slight the Use of Galls, in such Trials, yet I would thence urge them to make such Trials to be more warily made. Observations requisite in Trying Mineral Waters. And because it may be of some Use to observe the different Colours exhibited by such Trials, I shall add, the following Considerations, as Requisite to be thought on by him, who designs to make such Experiments. 1. That he ought to observe the Changes of Colours, made by such Tinctures, in a good Light; which may help a Curious Observer to distinguish what Minerals such Tinctures are impregnated with. 2. It way be of Use to vary the Shades of Colours, produced by Mineral Waters, either by dropping such Waters upon Paper, whose Pores are saturated with Vitriol powdered, or tinged with a Decoction of Log-wood: Several Variations in Colours may be also made, by dropping other Medicinal Liquors, either into the Mineral Waters; or the Infusion of Galls, before Mixture, or after. 3. I would recommend, for such Trials, not only the Parts of Astringent Plants, but also Animal, and especially Mineral Substances: For, besides the Astringents, I have contrived a certain Substance, which would not only turn a Vitriol Water impregnated with Iron black; but also One saturated with Copper; a Succedaneum, to which may be made, by adding to Sulphur as it melts over the Fire, and equal Proportion of Salt of Tartar finely powdered, stirring them till they incorporate, and become red: Which Mixture, being put into a Glass Retort, with half its weight of Salarmoniack, dissolved in Water; let it be distilled in Sand, shifting the Receivers as the Liquor drawn off, is tinged more or less; so that the strongest may be preserved by itself. And such Trials as these will be of more use, than those usually made with a bare Tincture of Galls; since there are several Mineral Substances and other Bodies, which Mineral Waters may be impregnated with, which discover not themselves in an Infusion of Galls: As Sulphur or Copper, may be so locked up in these Waters, as not to be perceived, till the Body of the Liquor is opened by some proper Additament. And even Arsenic itself, may be so disguised, as not to be perceived, when mixed with the Waters; yet if Spirit of Urine, or Oil of Tartar; per Deliquium, be dropped into a Solution of it, it presently precipitates in the Form of a white Powder; and so likewise, if a Solution of Sublimate be added to it. Whether Mineral Waters have Arsenic dissolved in them But to discover, whether Mineral Waters be impregnated with Arsenic or not, I put Dantzick, or English Vitriol into a Solution of it, either of which caused a dark precipitate gradually to subside. 14. Whether Spirituous Acids, volatile Alkalys, or Lixivial Salts will precipitate such Waters? 15. The Manner of Extracting Salts from such Waters, and what Quantities may be extracted? Guesses may be made concerning the Saltness of these Waters, by trying whether they will Lather with Soap? and if not, what Quantity of Curdled Matter they will yield? I have observed that even the lightest Waters will yield a small Quantity of common Salt. 16. How to discover what Acidity is to be found without Evaporation. Having taken a peculiar Method to try the Acidity of Mineral Waters, by mixing them with an Infusion of Lignum Nephriticum in simple Water, I found, that tho' Germane Spa, yielded a small Quantity, yet in that of Action, there was none discernible. 17. What may be observed by Distillation in Balnco? 18. What, and whether the same Quantity of Caput Mortuum, be afforded by Evaporation, and Distillation? 19 Whether Mineral Waters will acquire the same Qualities and Texture, by a Reunion of their Caput Mortuum, when distilled to such a Consistence, in Glass-Vessels exactly luted, which they had before? 20. What Changes, if any, Mineral Waters undergo by being boiled in Water, in a Glass Hermetically sealed? From whence might be learned whether a Change of Qualities would succeed an Alteration of Texture, without a manifest loss of Parts? And whether an Agitation of Parts, without the Influence of the Air, would precipitate any thing, or deprive it of its Power to turn a Tincture of Galls Purple? 21. How much the Mineral Waters exceed their Caput Mortuum in Proportien? 22. What Parts are contained in the Caput Mortuum, and whether dissoluble in Water? 23. How much the Saline and Terrestrial Parts differ in Proportion? 24. Whether in strong Fires, the Salts be Volatile or Fixed, and to what Degree? 25. Whether the Salts will Crystallize per se, or with other Salts, and what's the Figure of the Genuine, or Compounded Crystals? 26. Whether Acid or Alkaline Qualities are most predominant? The Acidity will either appear to the Taste or Smell; or may be discovered by turning Syrup of Violets red; as also, by making use of an Infusion of Lignum Nephriticum, which upon a Mixture of Acids loses its Blue Colour: Their Acidity may likewise be discovered by trying, whether they will be precipitated by Alkalys, or ferment with them. And if Alkaly be predominant, it, on the contrary discovers itself by a Lixivial Taste and Smell; and may be discovered, by turning Syrup of Violets Green, or precipitating a Solution of Sublimate, or Fermenting with Aqua fortis; or lastly, by increasing the Colour of a Tincture of Brasil or Log-wood in Common-water? And tho' we have no such Springs here in England, as afford Alkaline Salts; yet without question, in Egypt such may be found, since their Latron, or the Egyptian Nitre, abounds with a Salt of an Alkaline Nature: and I have obtained such an Alkaly, from that Famous Water of Bourbon in France, which would turn Syrup of Violets green, and ferment with Volatile Acids. If such Waters abound with Vitriol, they'll turn an Infusion of Galls black, and Vomit those that drink them; and, if an Alkaly be added, will yield a yellow Precipitate, upon dropping of Spirit of Urine, or Salt of Tartar into them. I have not found any of the Waters about London, to be impregnated with Vitriol; and I am told, that in France the Mineral Waters are so far from being impregnated with Vitriol, that there is a Vitriolate Spring in that Kingdom. As for the Nature of the Salt, which most Mineral Waters are impregnated with, I think that it is not to be referred to any Glass, but is either sui generis, and a peculiar one, or a Compound Salt, made up of such as the Water is impregnated with, in its Passage through the Earth; and that Purgative Salts may, by a Change of Texture, be made of Salts not at all Purgative, I the rather believe, because I have been told by an Ingenious Empiric, That a Salt which I made of Salt of Tartar, and Common Sulphur mixed together, had a gentle Purging Virtue. 27. In what Menstruums the Caput Mortuum may be dissolved? and in what it may not? Whether Volatile or Fixed, and what Qualities it hath in Respect of Colour or Smell? What Proportion of Salt Mineral Waters afford. It is to be admired, what a great deal of Caput Mortuum some Mineral Waters yield in Comparison of others; since those Waters: which are purely Diuretic have very little, if compared with the Caput Mortuum of Purging Waters: For tho' a pound of Barnet Waters, yielded a Drachm, yet the same weight of Tunbridge afforded but a Grain. And, It is not a little strange, that so small a Quantity of a Mineral should impregnate so much Water, as I have, by Trial, found a Grain of Iron Stone did, enabling it to Tincture an Infusion of Galls, deeper than Tunbridge or Germane Spa Water would. And I have tried, that half a Grain of Marchasite, dissolved in Spirit of Nitre, communicated a Tincture to 61440 Parts of Water; tho' Part of that Marchasite was Sulphur, and Part of it Caput Mortuum. And here it may be seasonable to take notice, That if so small a Portion of a Metalline Substance would, when grossly dissolved, impregnate so large a Quantity of Water; how much more may it, when raised in the Form of a Subtle Mineral Fume? and as in such a Form, it may impregnate a larger Quantity of Water, so will it be more apt to fly away, when exposed to the Air. And that Vitriol may probably rise in the Form of a Vapour, without losing its Qualities, is evident in Sublimate, which consists of Mercury, changed by an Addition of Salt and Vitriol; for some Vitriolic Parts being carried up in the Preparation, turn Opacous upon an Affusion of Spirit of Sulphur. But further, to make it evident, that the Particles of Iron may be considerably expanded, I dropped four Drops of a Vitriolic Liquor, made use of in Copperas-works, into twelve Ounces and a half of Water, and found, that it so much impregnated 1500 times its Proportion of Common Waters, as to make it strong enough to turn a Tincture of Galls Purple, tho' by Evaporation we found that 3 Parts of 4 of that Liquor were Water. 28. What Alterations the Earthy Parts of Mineral Waters undergo by Ignition; and whether they may be Vitrifyed per se? as also what Colours they impart to Venice Glass, if mixed with the Powder before Fluxion? 29. Of what use they are in Baking, Brewing, Tanning, or Dying of Colours, etc. 30. How many ways they may be made Artificially, and with what Proportion of Ingredients? CHAP. XI. Titles for the Natural History of Mineral-Waters, considered as a Medicine. IT may be worth Observing, in order to a more Complete Natural History of Mineral-Waters, what Constitutions they agree with, and in what Distempers they are Proper or Dangerous: What Sensible Operations they have; and whether their Effects be altered by Drinking them Hot or Cold; at the Well, or at a Distance from it: Whether Exercise, or the Warmth of a Bed, promotes their Operation: Whether they have any Occult Qualities. It may likewise be requisite to observe; What good Effects may succeed a due Preparation of the Body that drinks them, and what Advantage it may be to drop some Strengthening Stomachick into the First Dose: What Quantity is enough for the First Dose, and how it must be varied: How long they may be Drunk, and whether constantly, or with Intervals; whether Purging sometimes may contribute to their good Effects: What Regimen in the Six Non-Naturals is to be observed, whilst they are ataking: Which are the Signs that denote the kindly Operations of them; or their future ill Effects. What ill Accidents attend the taking of them, and how they may be Remedied, or Prevented. Whether it be proper to Purge after the Taking of them. What Effects they will have by Mixing other Liquors with them; or, by Boiling Meat in them; Whether a Salt extracted will be of Equal Effect, when Diluted in Fresh Water. What External Effects they will have, and of what use their Sediment is when Externally applied: What Effects they will have on Dogs, if injected into their Veins, or if they be kept with such for constant Drink. CHAP. XII. Of the Natural and Preternatural States of Bodies; especially the Air. IT is the General Consent of most Men, that the Determinate States of Bodies are not only first framed by what they call Nature; but that they are likewise preserved in those States, by the Superintendency of that Power; and that whenever they lose that State, they are said to be put into a Preternatural One. But if we consider, that such Changes proceed from Natural Causes, and that those New States depend on the like Catholic Agents, The Common Distinction betwixt Natural and Preternatural States ill grounded and the Established Laws of Nature; it will appear, That the Distinction Men usually make betwixt the Natural and Preternatural.▪ States of Bodies, is but ill-grounded; and that Preternatural, is only a Relative Term, intimating that that Body hath undergone a Change, either by the Operation of some unheeded or more noted Agent. For Matter being altogether void of Sense and Perception, and not affecting one State more than another, the Changes it undergoes, depend on the Alteration of its Textures, and New Position of its Parts, altered afresh, by that Agent, which such a Body was last exposed to. As a piece of Wax, is put into a New Form, by the last Impression, made by another Body upon it, without affecting one Form more than another itself. Ice a Natural State in some Places. And that the States of some Bodies, which are said to be Preternatural, as truly depend on Natural Causes, and the Established Laws of Nature as others, is evident in Ice and Water: In which Bodies, the Forms of each depend upon the Effects of External Agents; for, tho' in these Hotter Climates Water is Esteemed a Natural, and Ice a Preternatural State of that Substance; yet I am informed, that in Siberia, a Province belonging to a Russian Emperor, Water is froze most part of the Year; and at a small▪ Depth, from the Surface of the Earth, the Soil is froze throughout; where Ice is looked upon to be the Natural, and the Alterations made by a Thaw, and the Influence of the External Temperature of the Air, and the Sun Beams, are esteemed Preternatural States of Bodies. And further, tho' Butter in our Clime be sold in a consistent Form, and when it is melted, is looked upon to be in a Preternatural State; yet I am informed, that amongst the Europeans it is fluid, and is sold by Measure, and not by Weight, as here in England. And it is further observed, That several Substances, as Rosin of Jalap, Gum Lacca, and even Aloes itself, are considerablely softened in their Consistence, by the Temperature of the Air, and the Force of External Heat, whilst they pass under the Torrid Zone; so that I am told, that the former of the aforementioned Drugs was melted into a sort of Balsam, whilst it continued in Africa, but when it was brought to Spain, it put on a Consistent Form again: And tho' Aloes was soft whilst carried through America, and those hotter Climates, yet when it approached our Climate, it presently became hard. But to bring further Instances concerning the Natural and Preternatural States of Bodies, I shall observe, That according the Received Notion of Natural and Preternatural States, it is very difficult to determine the Natural State of the Air; for, not to insist on the different Temperature of the Air, as to Heat and Cold, in different Climes; It may be demanded, Since Heat and Cold, rarify and expand the Air, what is to be esteemed the Natural State of it, in Reference to Rarity and Density? And it is no less Questionable, what Place is most fit to determine its Natural State, since the State of it is not only different in several Countries; but in those Places at different Times: And that the Changes, as to the Density or Rarity of the Air, are very frequent, appears by the several Degrees of the Atmosphere's Gravity, evident in the Torrecellian Experiments, hereafter to be delivered. A forced State, the Natural State of the Air. But further: Except the States of the Air be said to be Preternatural, only in a Relative Sense, with respect to the State it was in, before it underwent the last Change, it is not impossible to make it out, That the Air is always in a Preternatural, because always in a Forced State; the Lower Parts of the Air being constantly pressed upon, and by the Weight of Incumbent Air, kept from expanding itself; but if the further it recedes from a forced State, the nearer it approaches to a Natural One, than the Force of the Fire must by Rarifying it, contribute to the Destroying of its Preternatural State; and by the same Reason the Air contained in our Pneumatical Receiver, when Part of it is drawn out, must approach to a Natural State, the Remaining Part having further Liberty to expand itself. To conclude this Chapter: From what hath been said, it appears, That that is truly the Natural State of a Body, in which it is preserved by a Natural Concourse of External Agents: And likewise from what hath been said, we may infer, That it is a common Error, That nothing Violent is Durable; since it is evident, that the Atmosphere we live in, is always in a Forced or Compressed State. CHAP. XIII. The Description of the Pneumatick Engine, and its Use. Physicomechanical Experiments touching the Air, in a Letter to the Right Honourable Charles, Lord Viscount of Dangarvan. My Dear Lord, PErceiving that several of the Virtuosos at Paris, intent in Examining, how far the Air was concerned in hindering the descent of Quicksilver, in the Torrecellian Experiment, concerning a Vacuum; I thought it seasonable to promote that Experiment; and to acquaint Your Lordship with my Attempts on that Subject, which may afford some Hints at least towards the Advancement of that Philosophy. A Subject which I the rather make Choice of; because, the Air being of so general use in Respiration, and, by it's almost Perpetual Contiguity, as well to our own Bodies, as those we are here concerned with, having Considerable Effects, in Producing those Various Diseases incident to Crazy Bodies, upon Changes of Wether, a Discovery of its Nature may be of Moment; and likewise, because it may show us how far it concurs in Exhibiting several other Phanomena. But before I present Your Lordship with the Experiments, it will not be improper to give Your Lordship an Account of the Engine concerned in the making of them. A Description of the Pneumatical Engin. It consists then of two Principal Parts; a Glass Vessel, and a Pump to suck out the Air contained in it. The First of which is a Glass, furnished with a Hole at the Top, to which a Cover is adapted, and also a Stop-Cock, fitted to the Extremity of its Neck below; the Cavity of it being large enough to contain about 60 lib. of Water, allowing ʒ xuj. to each Pound. The Diameter (B C) of the Top of the Vessel (A) is about four Inches, which is encompassed with a Lip, almost an Inch in Height; the Use of which is for the Cover to rest on; which is described in the second Figure, where (D E) denotes a brazen Ring, which is to cover and to be closely cemented on the Lip (B C) of the first Figure. To the Internal Orifice of this Ring is adapted a Glass Stopple, so exactly, as to prevent any considerable Access of external Air: In the midst of this Cover there is a Hole (H I) about half an Inch Diameter encircled with a Ring or Socket, to which is adapted a brazen Stopple (K) so tightly, that it may be turned round without admitting in the least Air. Through the lower end of it there is a little Hole (8) made for the Passage of a String (8, 9, 10) which is likewise to pass through a small brazen Ring (L) fixed to the bottom of the Stopple (F G) the use of which String is to move what is contained in the exhausted Vessel, when stopped. That the Stop-cock (N) in the first Figure, might more exactly exclude the Air, a thin Plate of Tin (M, T, V, W) was soldered on the Shank of the Cock (X) of a Length proportionable to the Neck of the Receiver, which was cemented, with a Cement made of Pitch, Rosin and Wood-ashes, poured hot into the Cavity of the Plate; and to prevent the Cement from running into the Orifice (Z) of the Shank (X) it was stopped with a Cork, to which was fixed a String, that it might be drawn out of the upper Orifice of the Receiver, and then the Neck of the Glass Receiver being pressed moderately hot into the Cement, it filled the Interstices betwixt the tin Plate and the Receiver, and also, betwixt the Receiver and the Shank of the Cock. The lower Part to be described is made up of an Air-pump, supported by a Frame of Wood with three Legs (111) so contrived, that, for the freer Motion of the Hand, on one side it may stand perpendicular; the midst of the Frame, a Piece of Board is nailed (222) to which the Pump is fixed. The Pump is made up of four Parts, viz. An exact and strong Cylinder, endued with a Cavity about three Inches cross; to which a Sucker (4455) is adapted, made up of two Parts; one of which (44) being not so large in Diameter, as the Cavity of the Cylinder, a thick Piece of tanned Leather is nailed on it, by the Addition of which, it closes so exactly to the Cylinder, that the Air cannot insinuate; The other Part being a thick Plate of Iron (55) is firmly joined to the middle of the former Part; it is a little longer than the Cylinder; one Edge of it being smooth, and the other indented, to the Interstices of which the Teeth of a small Jaton Nut (α β) are to be adapted, which is fixed by two Staples (22) to the under-side of the Board nailed transverse (222;) on which the Cylinder resting, it is turned by the Manubrium (7.) The last Part of the Pump is the Valve (R) being a Hole at the Top of the Cylinder, which is taper towards the Cavity: To this is fitted a brass Peg, to be put in or taken out, as Occasion requires. The Engine being thus delineated, the Stop-Cock must be well oiled with Salad Oil, to stop the Intervals of the Internal Surfaces of its Parts, and also, that it may with less difficulty turn the Key (S) at Pleasure; for the like Reasons the Sucker as well as the Valve is to be oiled also. And here it is as much strange as to be admired, That when Oil or Water separate, have failed in effecting our Design, a Mixture of both hath proved effectual. Lastly, That the Ingress of Air betwixt the brazen Cover and the Ring, may be likewise prevented; it will be convenient to plaster the Edges with the former Cement, laid on with a hot Iron, that it may the better fill the little Cavities. Things being thus ordered, That no Air may remain in the Cylinder, the Handle is to be turned till the Sucker rises to the Top of it; and then, the Valve being shut, it is to be drawn down to the bottom; by which Means, the Air being driven out of the Cylinder, and a Succession from without being prevented, the Cavity of the Cylinder must be emptied of Air, so that the Turn-cock being turned so as to afford a Passage betwixt the Receiver and Cylinder, Part of the Air before lodged in the Receiver will be drawn down into the Cylinder, which, by turning back the Key, The Method of Managing the Pump. being prevented from flying back into the Receiver, may, by opening the Valve, and winding up the Sucker, be forced into the open Air; and so, by reiterated Exsuctions of the Air out of the Receiver, and Expulsions of it again out of the Cylinder, it may be exhausted as the Nature of the Experiment requires. Having thus given your Lordship a Description of the Engine, and Cautions for the Prevention of the Ingress of Air, necessary in some more curious Experiment; I shall in short acquaint your Lordship, That the Experiments I proceed to entertain your Lordship with, are such, as require not such Exactness in the forementioned Cautions, provided the Pump be well plied and the Crannies not considerable. EXPERIMENT I. The Manner of Pumping out the Air. A Digression concerning the Spring and Elasticity of the Air, in Order to a more clear Apprehension of subsequent Experiments. FROM what hath been delivered it appears, that, the Sucker being wound up, and, upon stopping the Valve and turning the Key, drawn down again, the Air will be equally expanded both in the Receiver and Sucker; and upon returning the Key, and opening the Valve, near a Cylinder full of Air will be expelled; but the Receiver, by reiterated Excursions, being more and more exhausted, less proportionably is forced out; so that at the last, before you need to open the Valve, the Sucker will rise almost to the Top of the Cylinder; and if, when it is so exhausted, you let go the Pump, and the Valve be stopped, the Sucker, merely by the Force of external Air, overpowering that more rarified Air within, will be forced up to the Top of the Cylinder; where we may observe, That as the Sucker is pressed higher by external Air, so it is an Argument of the Receiver's being more or less exhausted; the Air in the Sucker being accordingly more or less able to resist the external, as it varies in Quantity: We may observe also, That whilst the Receiver retains any considerable Quantity of Air, there is a brisk Noise upon turning the Key. A Springiness in the Air. But to render these Experiments more intellible, I shall take Notice to your Lordship of a Notion, which may explicate them; which is, That the Air consists of certain springy Particles, which, being bend and pressed together by incumbent Bodies, always endeavour to remove that Pressure, and to dilate themselves; which Notion may be confirmed, by considering, that the Air consisting of Parts incumbent on one another, the uppermost, by their weight, must needs compress the lower; which compressed Parts must consequently have a Power of self-Dilation: So when a Fleece of Wool compressed, upon the Removal of that Pressure again expands itself, the Springiness of the Air may likewise be explicated by supposing with the Ingenious Des Cartes, that the Air is a Congeries of flexible Particles, of various sizes and very irregular Figures, raised by the Heat of the Sun, and swimming in that Matter, which encompasses the Earth; which being, by that Aether that floats about them, kept separate and in a violent Agitation, acquire that Springiness which they would lose in some measure by being compressed. By both these ways the Springiness of the Air may be explained; yet by which with most Reason I shall not now dispute, being not so much concerned about the adequate Cause of that Springiness, as to manifest, that it hath a Springiness, in order to show the Effects of it; for I am not satisfied, whether either so far explains its Nature, as to make it intelligible. But in opposition to this Notion it may be alleged, that though it were granted, that the Air is made up of springy Particles; yet, it would only account for the Expansion, and the Dilatation of the Springs of the Air, when apparently compressed in Wind Guns and other Pneumatical Engines; whereas from these Experiments it does not appear, that there was any Compression before the Air was included in those Guns. To remove this Difficulty, there are several Experiments which prove, that our Atmosphere is not light, but heavy, in respect of some Bodies, one of which I shall mention here, which is this, that a Lamb's Bladder dried, whose Cavity contained two thirds of a Pint, being pressed together, and counterpoised in a very nice Balance, and being pricked, upon the avolition of the Air contained in it, lost a Grain and an eighth Part of what it weighed before; from whence, if we may conceive, that it hath weight, it follows, that a Column of Air of many Miles high leaning on those below, is enough to compress and bend their Springs; as when Wool is heaped to a considerable height, that which lies under is compressed by that which lies upon it; and if upon a Parcel of Air, so large a Quantity lies, no wonder, that upon the Removal of that Pressure, it powerfully expands. As for the Objection, that Water varies not in its Weight in the lower from the upper Part, it may be answered, that the difference betwixt Air and Water is very considerable; the last not being capable of Compression; whereas Air is. To which may be added the Experiment tried by Monsieur Pascal (the Son) at the foot, the middle and top of that high Mountain (in Avergne) called Le Puy de Domme, Why Mercury is suspended higher at the bottom than the top of a Hill. where the Mercury subsided above three Inches more at the Top than the bottom; the Reason of which is, that the Air less vigorously pressed against the Quicksilver at the Top, and so was less capable of bearing it up. And if it be objected against what hath been proposed, that if it were so compressed, it would not be so ready to yield to the slight Force of Flies, and even Feathers, it may be answered, that as a Piece of Wool squeezed together, makes a manifest Resistance to the Pressure of the Hand; so the Air does to those Bodies, though its Resistance is not strong enough to overpower their Motion, the Parts of it being in a continual Disposition to yield to solid Bodies, upon the Account of its Fluidity, and the perpetual Motion of its Parts, occasioned by their continual Endeavours to expand and unfold themselves. EXPERIMENT II. Of the Pressure of the Air against the Sides of the Bodies it encompasses. The Pressure of the Air included within an Ambient Body explained. The Air presses upon the sides of Bodies it encompasses. IF, when the Air is almost drawn out of the Receiver, one endeavours to lift up the Brass Key which is placed in the middle of the Brass Cover; it will be as difficult to raise it, as if a considerable Weight were tied to it; for the Spring of the Air included in the Receiver being weakened, and not able to bear up strong enough against the bottom of the Stopple, as powerfully as before; whoever lifts up the Stopple, must likewise bear up the whole Pillar of External Air, which presses upon the top of the Stopple: But if the Air be gradually permitted to get into the Receiver, the Internal Air being more compressed, and its Spring increased, it bears up against the Stopple more powerfully, and the Pressure of the Internal and External Air being brought nearer to an Aequilibrium, the Stopple may proportionably be lifted up with less difficulty; till at length, the whole Cavity of the Receiver being filled with Air, it may easily be taken up. But it's thought strange by some, how the Pressure of the Included, can be any ways proportionable to the Pressure of the External Air; since it is so encompassed by the sides of the Receiver, that those Pillars of Air, which would press upon it, if open to the Air, are only icnumbent on the External Superficies of the Receiver; but to unfold this Difficulty, The Air enclosed in the Receiver Acts by virtue of its Spring. we may consider, That as a piece of Wool● squeezed in one's Hand, and so enclosed in a Box, is kept from expanding equally by the sides of the Box, as if it remained in one's Hand; so the Air compressed by the Incumbent Asmosphere, and conveyed in that compressed State, into the Receiver, is equally kept from expanding itself by the sides of the Receiver, as if it were still squeezed together by the weight of the Atmosphere: And if it should further be objected, that if the Air included in the Receiver were so confined by the sides of it, it's continual Endeavour to expand would break the Glass: It may easily be answered, that the expansive Force of the Internal Air, is counterpoised by the Compressure of the External, and consequently there being an equal Pressure on both sides, it is preserved entire; for a like Reason those slender Bubbles, which Boys usually blow up with Soap and Water, continue whole for a good while, the Internal and External Air, being compressed to a just Aequilibrium. EXPERIMENT II. Concerning the Force requisite to draw down the Sucker: The Opinion of a Modern Naturalist examined. What Weight is requisite to draw down the Sucker. THough the Sucker may be easily drawn down, by the help of the Manubrium▪ yet without that it will require a Force capable of raising so much of the Atmosphere as presses upon it: The Reason of which is evident, from Mercury suspended in a Tube; for tho' the Weight of the Atmosphere is able to balance and keep it up to twenty five Digits; yet if the suspended Mercury exceeds that height, it presently over-powers the Pressure of the incumbent Atmosphere, and subsides to its just height. And as from hence we may learn, why it is so difficult to draw down the Sucker; so it likewise teaches us, for what Reasons the Sucker, when so violently forced down, upon a Relaxation of that Force rises up again; for the Spring of the Air included being weak, it must consequently be buoyed up by the Pressure of the External, till that which is contained in the Receiver be equally compressed, so as to be able to resist the Pressure of the Atmosphere. There is one Thing more remarkable in this Experiment, which is, that if the Valve be stopped close, when the Sucker is raised to the Top of the Cylinder, it finds an equal Resistance by the Pressure of the Atmosphere when first drawn, as when nearer the Bottom of the Cylinder; from whence we may gather, that what an Eminent Modern Naturalist delivers concerning the Reason of the violent Ingress of exhausted Air, viz. That it is increased by the Addition of that Force, which it receives from the Air sucked out, is a mistake; for were it so, it would be more difficult to draw down the Sucker, when it is further from the Receiver, a greater quantity of Air being exhausted. But from what hath been premised in the first Experiment, it is evident, that the weakened Pressure of the Internal Air, is sufficient to account for the more violent Ingress of the External. EXPERIMENT iv Concerning the Swelling of a Bladder, The Opinion of a Learned Author Examined. The Expansion of Air in a Lamb 's Bladder in our Receiver HAving conveyed into the Receiver a Lamb's Bladder, well dried and limber, and half full of Air, the Cover being luted on, and the Pump set on work; we observed, that as the Air in the Receiver was gradually exhausted, that in the Bladder was accordingly expanded, till the Receiver being near fully exhausted, the Bladder seemed very much distended, with the included Air. And to confirm our Guests, that the Expansion of the Air in the Bladder, proceeded partly from the weakened Pressure of the ambient Ai, rwe gradually left in the external Air, and found, that the Bladder by degrees subsided till it became as empty as before: But one thing Remarkable in this Experiment was, that the more the Receiver was exhausted, the more sensibly the Bladder was distended. And lest in this Experiment it should be doubted, whether the Distension of the Bladder did not rather proceed from the Fibers of the Bladder, returning of their own accord, to their natural Extension upon the removal of the external Air, we put in two empty Bladders along with the former, and found them very little extended upon the Exsuction of the Air. And the like Phaenomena were afforded, by repeating the Experiment with a Bladder, which was half empty, and half filled with Air, the empty Part being parted from that which contained the Air, by a Ligature. EXPERIMENT V Concerning a Bladder which burst in the Receiver, and another by Heat. The Force of the Airs Expansion. HAving put a Bladder moderately Blown into the Receiver, before the whole Air was drawn out, the Air presently expanded and broke the Bladder with a considerable Crack; and though this Experiment frequently succeeds, yet if the Bladder be one that is too dry, it is hard to tie it so fast, but that some of the included Air will get out, and so frustrate the Trial. But to be fully informed whether the Air is out or not, we may be satisfied, by admitting Air afresh into the Receiver, which will, if the mentioned Accident happens, compress the Bladder more than when it was first put in. But it is not only possible, that the Air should expand itself so powerfully in an exhausted Receiver; but if a Bladder well blown, be brought near a good sire, the included Air will burst the Bladder with a considerable Noise. EXPERIMENT VI. The Airs Expansion measured. TO try how much the Air was capable of being expanded, we fixed the Neck of a wet Lamb's Bladder to the Neck of a Viol; which being conveyed into the Pneumatical Receiver, upon the Exsuction of the Air, we observed, that the Air which was contained in the Cavity of the Viol was so far expanded, that tho' the Viol was able to contain above five Drachms of Water, if filled and distended the empty Bladder, which was large enough to hold five Ounces and half a Drachm. In which Experiment, the expanded Air possessed nine times as much space as it did before Expansion. But to measure the Air's Expansion more nicely, we fixed a Glass Bubble to one end of a Cylindrical Pipe, hermetically sealed; the Diameter of whose Boar was about a quarter of an Inch; and having pasted a Piece of Parchment upon the outside of the Tube, which was divided into twenty six equal Parts, and marked with black Lines, we filled the Cylinder almost full of Water, so that, after a few Trials, by inverting the Cylinder, and stopping the open End with one's Finger, we could perceive, that as much Air might be permitted to rise up to the Bubble, as was equal in Extension to the Breadth of one of those twenty six Divisions; When this was done we fitted the open end of the Cylinder to a Glass Viol., which was filled with Water to the Height of half an Inch; all which being put together into a Pneumatical Receiver, after a few Exsuctions, the included Air was so much expanded, as to extend itself to the Surface of the Water; in which Experiment the expanded Air took up thirty one times as much Space as before. And this Experiment being repeated in a Cylinder, which afforded a larger space for the Air's Expansion, it took up above sixty times the space it did before. And repeating the like Experiment with a Glass Pipe thirty Inches long (part of it having a Hole in the Cover to stand out through) by weighing the Water in a nice Pair of Scales together with the Pipe, first with the Bubble of Air included, and after when the Tube was wholly filled with Water, we found, That the Air which possessed but the Space of one Grain of Water had been expanded, in the exhausted Receiver so much by its own 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, as to take up 152 times its Space before Extension. And since Marcennus affirms, That the Air may be so expanded by Heat, as to take up seventy times its Space, I conveyed a Cylinder of the former Magnitude into the Receiver, and found, That upon the Exsuction of the Air in the Receiver, that in the Cylinder descended down almost to the bottom of it, the lower Surface of it being very convex, and seeming several times to knock upon, and rebound from the bottom of the Viol; which was an Argument of the expansive Force of the Air; since the Water it depressed, upon the drawing out of the Air, was much below the Surface of the Water contained in the Viol. EXPERIMENT VII. What Figure best resists the Pressure of the AIR. HAVING got a thin Glass Bubble, which was large enough to hold about five Ounces of Water, to which was fixed a slender Neck, about the Bigness of a Swan's Quill, we moderately exhausted the Air out of the Receiver, and then taking it out of the Pump, we joined the Neck of the Bubble to the lower Orifice of the Receiver, stopping the Crannies with melted Plaster to prevent the Ingress of the Air; and tho' the Glass was as thin as Paper, yet upon turning the Key of the Stop-Cock, and giving the Air included in the Bubble Liberty to expand, the Bubble sustained the Pressure of the whole Atmosphere, without being broke. EXPERIMENT VIII. The former Experiment illustrated. WE took a Glass Alembick, which was large enough to hold about Three Pints, represented by the Seventh Figure; The Rostrum (E) being hermetically closed: In the Top of the Rostrum was a Hole, into which, one of the shanks of a Stop-Cock of an ordinary size was cemented, the other being fixed with Cement in the upper Part of the Pump; which being done, and the upper Orifice of the Alembick being covered close with a Plate of Lead exactly adapted to it, upon drawing the Air out of the Receiver the Glass presently cracked; which Crack is represented by the Line (a, b) and this Flaw extended itself further accordingly as the Air was more exhausted, yet this Glass Vessel was near twenty times thicker than the Bubble. And that the Figure of the former Glass enabled it so much better to sustain the Atmosphere, was further confirmed by suspending one of the Bubbles hermetically sealed in the Receiver, which so strongly resisted the Expansion of the Air contained in it, as to continue whole, when the Receiver was exhausted. EXPERIMENT IX. A Confirmation of the former Experiment: An Experiment to show that these Phaenomena exhibited in Vacuo Boyliano proceed not from a fuga Vacui, etc. A Confirmation of the former Experiment, etc. HAving put the end of a slender Glass Pipe into a Viol, which was large enough to contain four Ounces of Water, and fixed it to the Neck of the Viol with a Cement of Rosin and Pitch, so that the end of the Pipe almost touched the bottom of the Viol, as in Fig. 6, this Viol was conveyed into a small Receiver, as much Water being put into it, as wrought a little above the bottom of the Cylinder; the upper End of the Pipe being most of it without the Vessel, a Hole having been purposely made for it in the Top of the Receiver: The Event of which Trial was, that upon drawing the Air out of the Pump, the Weight of the Atmosphere internally pressing into the Pipe, and the Spring of the Air within the Receiver, not equally pressing against the sides of the Bottle, which were exposed to it, a Piece of the Bottle burst out of the side of it, with such a Force as to crack the Receiver in several Places; and having reiterated the Experiment with a round Glass Bubble, the Leaden Cover of the Receiver was not only depressed, by the Weight of the Atmosphere, so as to thrust out one side of the Receiver, but the Glass Bubble was cracked into Pieces with such violence, as to tear a Bladder, which it was encompassed with to keep it from breaking the Receiver, in several Places. Before I proceed to the next Experiment, it may be requisite to advertise, That though the larger Receivers are apt, upon some Trials, to crack; yet, they are not rendered altogether useless, since when the Air gins to be exhausted, the ambient Atmosphere compresses the Lips of the Glass closer together. But if the Crack be considerable, it may be cemented with a Plaster made of Quicklime and Scrape of Cheese ground together very finely in a Mortar, and made into a Paste with a little Water, which being spread upon a Cloth about three Inches broad, must be applied to the Crack. EXPERIMENT X. Of the Flame of a Candle in a Receiver. HAVING suspended a Tallow Candle in our Receiver, we found, That upon an Exsuction of the Air, it was presently extinguished; but another being suspended there without pumping the Air out, it burned a little longer, the Flame of both before they went out gradually contracting and ascending almost to the Top of the Wieck with a blue Flame. In which Experiments it was observable, that when the Air was drawn out, the Wieck was presently extinguished, emitting very faint Effluviums, which risen a little Height, and dispersed themselves in the Receiver very faintly; whereas when the Air remained in the Vessel, the Smoke ascended in a. Cylindrical Stream, very briskly and recoiled from the Cover. To try what difference there would be in the Phaenomena exhibited by a Candle made of Virgin's Wax, and the former, I suspended several small ones, stuck together, and found, that they would be immediately extinguished before the Cover could be cemented on; but having let down one of them alone, we observed, that upon the Evacuation of the Air, it continued to burn about a Minute; but if the Air was not pumped out, the Flame continued more vivid and lasting: And, as in the Former Experiment, the Flame gradually risen to the Top of the Wieck; so in the Latter, it was depressed nearer the Bottom, before it was extinguished. EXPERIMENT XI. Concerning the Burning of Coals, and the Continuance of the Heat of a piece of Iron in Vacuo Boyliano. HAving suspended a Screw made of Wire in the Receiver, such as Fig. 10. represents, it being first filled to the height of five Inches, with live Wood-coals; upon the first Exsuction made by the Pump, they grew dim, and the Pump being plied for three Minutes, they were quite deprived of their red Colour, and seemed extinct; but when they were taken out of the Receiver, they were rekindled again; and being let down into the Receiver afresh, without Pumping out the Air, they continued red for a Minute longer than before; but a like quantity of Live-coals, continued to burn half an Hour, in the open Air. But a piece of Red-hot Iron, being suspended in the same Wire, upon an Exsuction of the Air, it seemed not to be sensibly altered; but continued red for 4. Minutes; neither was it altered by readmitting the Air into the Receiver, tho' Fumes, which were raised from some Wax, which stuck to the Wire, were much more expanded, when the Air was pumped out, than upon its re-ingress. But one thing observable, was, that whether the Air was sucked out, or not, the sides of the Receiver were considerably heated by the Effluvia trasmitted from the Iron. EXPERIMENT XII. Concerning the Burning of a Match. HAving suspended a lighted Match in the Receiver, it presently filled the whole Cavity with Smoke; which, together with Air, being pumped out, we could discern the Match to burn still more languid, till at the last it seemed to be totally extinguished; yet some time after, upon a fresh ingress of Air, it renewed its Fire, being blown up afresh by the Access of that Airy Body. EXPERIMENT XIII The Reason of the aforementioned Effect. HAving suspended a lighted piece of Match, together with a Bladder, to try whether the Smoke would hinder the Distension of the Bladder, as also whether the Light of the Match would be put out by its own Smoke; I observed, that it afforded the same Phaenomena mentioned in the foregoing Experiment, except that after Successive Re-admissions of the Air, it being excluded for some time, the Fire was totally extinguished. Besides which, the following Phaenomena were to be observed: First, That upon the turning of the Stop-Cock, the Cavity seemed immediately darkened, as if it proceeded from a Change of the Position of the Parts of the Smoke. Secondly, That a kind of Halo, consisting of some Exhalations hovered about the Flame. And Lastly, It was observed, that the Fumes did not in the least obstruct the Distension of the Bladder. Having tried the Former Experiment with a lighted Match, in a small Receiver, I found, that the Fire was quite extinguished with its own Smoke, before the Cover could be cemented on, except the overplus of Smoak was successively pumped out, and a Supply of Fresh Air was let in at the Stop-Cock; which Method would contribute to the Preserving of it. EXPERIMENT XIV. Of the Striking of Fire, and Explosion of Gunpowder in Vacuo Boyliano. Gunpowder exploded in Vacuo Boyliano, etc. HAving fastened a Pistol to a Prop, which was placed in a Perpendicular Situation in the Receiver, and having tied a String to the Tricker, the other End of which was fixed to the Key abovementioned, in the middle of the Cover, we turned the Key round, to shorten the String; by which means the Tricker being checked, and the Flint as it is usual, falling upon the Steel, it struck Fire, tho' the Receiver was exhausted, as a Pistol usually does; tho' by the strongest Collision we could contrive, we could not, in our Engine, strike Fire with two pieces of Steel, striking one upon another. But we observed, That having endeavoured several times, without Success, to fire Gunpowder, we, but once or twice, met with the desired Effect: Where we observed, That the Flash was more expanded, than if it had been exploded in the open Air; and that when the Flash was extinguished, the Receiver was full of Smoke, the Parts of which moved up and down very briskly, but much swifter, when Air was permitted to return into the Cavity of the Receiver. EXPERIMENT XV. The Vnusefulness of Kindling Bodies enclosed in Vacuo Boyliano, with a Burning-Glass. HAving conveiged some Black and Dark Combustible Matter, into a small Receiver, and placed it in the Sunshine; a Good Burning-Glass threw the Rays of the Sun so powerfully upon it, as to make it smoke, and fill the Receiver; but the Air getting into the Cavity of it, we could not prosecute the Experiment. And having repeated the Trial in our Large Receiver, we found the Glass so thick, that it broke the Rays of Light, and scattered them so much, that when they fell upon the Combustible Matter, they were altogether incapable of working any considerable Effect upon it. EXPERIMENT XVI. The Operation of a Loadstone. HAving placed a piece of Wood in our Receiver, with a piece of Iron, in a Perpendicular Line, upon it; and fixed a well-poised Needle upon that, we pumped out the Air, and then applied a Needle to the outside of the Receiver; and observed, That the Loadstone drew or repelled the Needle, as a Loadstone usually in the open Air; and the Needle, upon a Removal of the Loadstone, after some tremulous Vibrations, pointed North and South again. EXPERIMENT XVII. The Gravity and Rarefaction of the Air examined, by the Torrecellian Experiments; together with Considerations concerning a Vacuum, etc. The Gravity of the Air, etc. COnsidering that it would be a very probable Method, to inform us, how far the Pressure of the Atmosphere, contributes to the buoying up of Mercury, in a Cylinder, so many Digits above the Surface of the Mercury it leans on, to try, whether in our Engine, as the Air was more or less exhausted, the Mercury in the Tub would accordingly subside; we filled a Glass-Cylinder Hermetically sealed with Mercury, whose Boar was about a quarter of an Inch Diameter, and 3 Foot long; which being inverted in an oblong Box, and carefully let down into the Receiver; and the Cover lutedon, the Tube came through the Hole in the midst of the Cover, the Crannies being filled with melted Diachylon; where it was observed, That the Mercury remained elevated to the same height, as if the Foot of the Tube had been pressed upon, by the Atmosphere, the Air included in the Receiver being in a compressed State, and acting by Virtue of its Spring. The Cylinder of Mercury being thus placed in the Receiver, we caused a Cylinder of Air to be pumped out, and after that, another, observing the Mercury after each, gradually to subside; till at the last, it subsided a considerable way in the Pipe, down into the Body of the Receiver: and to put it beyond dispute, that the Subsiding of the Mercury, depended upon the weakened Spring of the included Air, and the Aequilibrium betwixt the Pressure of that, and the Gravity of the Mercury; we turned the Key, and permitted Air gradually to re-enter; and observed, That the Mercury accordingly risen in the Pipe, almost to the height which it was first suspended at; and the Reason why it was not raised quite so high, was, because several Bubbles of Air, which were before mixed with the Mercury, rising above it, depressed, and kept it from ascending, by taking up more room in the Top of the Cylinder. In trying of which Experiment, having once made use of Diachylon Plaster, to stop up the Top of the Tube, we found, that tho' the Mercury subsided considerably upon the Operation of the Pump; yet the Air so powerfully insinuated itself through the Diachylon Plaster, that it sunk in the Pipe insensibly of itself. Another thing observable in this Experiment, was, that if, when the Air was exhausted, it were again permitted to run in too fast, it would go near to break the Cylinder, by forcing the Mercury up too quick. Besides we observed, as we have before intimated, That tho' upon the First Exsuctions, the Mercury subsided above an Inch; yet when it was low in the Receiver, it would not subside over the Breadth of a Barley-corn; besides, by reason of the Parts of the Air, tending to a Restitution of their Springs, it checked and caused the Quicksilver after its descent, to fly back again a little after each Exsuction. Another thing remarkable in this Experiment, is, That having tried it in one of our small Receivers, we found, that at one Exsuction it fell 18 Inches and a half, and at another time 19 and a half; from whence we may infer, that it might be of no small use to consider, the various Phaenomena afforded by the different Magnitude of the Receivers, in which these Experiments are made; and also the various Boars of the Cylinders, which contain the Mercury; for thence one might probably guests at the Quantity of Air extracted out of the Receiver, by the Subsiding of the Mercury in the Tube. To the foregoing Observations, we shall add, That having once tried the Experiment, in a Tube about two foot long, I found, that upon the first Exsuction, the Mercury fell above a Span, and afterwards subsided by degrees, till the Air was readmitted, and then it was raised near to the top of the Tube again. Lastly, It hath been observed, That when, by the help of the Pump, more Air hath been squeezed into the Receiver, than what was forced in by the Weight of the Atmosphere, the Mercury would rise above 27 Digits in the Tube, and would be suspended at that height, till the Air was again let out. Concerning a Vacuum. Having said thus much of the Torrecellian Experiment, and the several Phaenomena observable in it, perhaps it may be expected, that I should say something, concerning that Controversy, Whether or no there be a Vacuum in the Receiver, when the Air is pumped out: But being unwilling to take it upon me to determine so nice a Controversy; I shall only intimate, that were the Cavity of the Receiver void of Matter, it would be a difficult thing to conceive, how we should have visible Ideas of things contained in it; since they must either be conveyed to our Sensory by the reflected Rays of Light, or they must proceed from some sensible Emanations from the Bodies themselves. And from the foregoing Sixteenth Experiment, it appears, That the Effluvia of a Loadstone do permeate the Cavity of the Receiver, which makes it probable, that the Magnetical Steams of the Earth do so too. But on the other hand, it may be alleged, That since the Effluvia of a Loadstone may be admitted into the Receiver, when it seems full of Air, it may be urged, that the subtle Emanations of that Substance are only dispersed through the Vacuities of the Air; and consequently when that Air is exhausted, the Spaces which the Air possessed before, may be left void of Matter; for from the Thirteenth Experiment it appears, that Matter, which, if closely pinned up together, takes up but a small Space, may be dispersed throughout the Receiver, a very small Portion of the Match being able to fill the whole Cavity of it with Fumes. And as for the Arguments before alleged in favour of a Plenitude; they rather seem to argue, that it may be, than that it really is; and the Consequences usually drawn in Proof of such a Plenitude, are rather grounded on the Cartesian Notions of a Body, than on Substantial Experiments; for they thinking it a Contradiction in Adjecto so say, a Space can be void of Body, since they make Body and Extension inseparable; they therefore in favour of their own Doctrine draw Inferences from their own Positions to argue for a Plenitude. But to leave so Nice and Doubtful a Dispute, I shall proceed to lay down the following Advertisements: First, That the Difference which sometimes happens betwixt the rising of Mercury here in England, and beyond Seas, being about two Digits, it rather proceeds from the Shortnese of our English Inches, compared with those beyond Seas, than any such considerable Difference in the Weight of the Atmosphere. Another thing to be advertised is, That except more than ordinary Care be taken, when the End of the Cylinder is immersed in the Vessel of Mercury, several Bubbles of Air will rise to the Top of the Tube, which, being condensed with Cold, will permit the Mercury to rise higher in the Tube; but being expanded with Heat, would sensibly depress it. And, If it should be demanded, What Methods are to be taken to prevent the Intrusion of the Air, the following Requisites are to be observed: First, the lower Orifice of the Cylinder must be smooth, and so much inverted on each side, as not to exceed a quarter of an Inch in Diameter. Secondly, the Tube must be filled so full, as not to admit of any Air, betwixt the Finger and the Mercury. Thirdly, before the Tube is quite filled, it will be requisite to invert the Tube, that the Air included in it, may, by ascending to the Top, and upon a Re-inversion back again, gather all those little Bubbles of Air, which are dispersed through the Mercury, as it passes from one end of the Cylinder to another; and to drain the Mercury more exactly you may, by applying a hot Iron, cause those less Bubbles, which are not excluded by the former Method to break forth, which will be promoted by shaking the Vessel upon every Drop of Mercury, put into the Pipe. By which Method, having in a great Measure cleared the Tube of Air, I have, in one, that was pretty short, raised the Mercury to no less than 30 Digits and an eighth. EXPERIEMINT XVIII. The Variation of the Rise of the Mercury in the Glass-Cylinder, and the Reason of it considered. HAving filled a Tube about 3 foot long, with Mercury, and placed it in a wooden Frame in the Window, I observed, the Mercury was sensibly depressed in hot Wether, by the Expansion of the Air, which swum about it, and raised again in Cold; the Altitude very often varying without any manifest Cause: So that in five Weeks time it had ascended and descended about two Inches; the utmost descent below the Altitude of its first Suspension, being 9/16 of an Inch; and it's utmost Descent being 7/16, and it is not improbable, but that the Variation of the Altitude of the Mercury, would have been more considerable, had the Experiment been tried in a longer Tube, and in the open Air. And here it may be seasonable to take notice, that could there be any sensible Variation, observed in the Altitude of the Mereury upon the Ebbing and Flowing of the Sea; it would be of no small Moment in determining whether the Pressure made upon the Air, by the Moon, were any ways concerned in causing the Ebbing and Flowing of it, and such like Phaenomena. But to return to what we observed further: Having taken the Cylindrical Tube out of the wooden Frame, on a snowy day we observed, that the Mercury was raised Twenty nine Digits and three Quarters, above the Basis which it leaned on. If it should be asked, from whence these Variations in the Altitude of the Mercury. proceeded? I shall offer the following Considerations. The Reasons why Mercury is not always equally suspended. First. That the Air above the Mercury, being very weak, and not able to make any strong Resistance to the Rising Mercury, it may be esteemed a Cause, why it rises no higher, because the Asmosphere is able to sustain no more of it; forasmuch as the Mercury and the Atmosphere are balanced in an Aequilibrium; for the Resistance which the Air above the Mercury can make, is so small, that it would rise but very little higher, were there none at all in the Top of the Tube. Secondly, We may consider, that the External Air is subject to many more Alterations and Changes, than the Internal contained in the Top of the Tube, the latter being subject to be wrought on only by Heat and Cold: But the former is subject to many and considerable Alterations, besides those observable in this Experiment, the Effect of its fainter Changes being evident by their Effects on bruised and feeble Bodies. And that there are considerable Changes in the Air, Considerable Changes in the Qualities of the Air. is further evident from what Kircherus, during his Stay in Malta observes concerning Mount Aetna, which he could see from that place on some days, tho' on others, which seemed clear, the Air was so condensed, that he could not discern it; and thet the like Changes of the Air have sensibly altered the Prospects of several Places, is too commonly known to need further Instances: And we ourselves have often taken Notice of plentiful Steams and Exhalations in the Air, by the use of Telescopes, which could not otherwise be taken notice of, which after a Shower of Rain would presently disappear: And that such Steams do rise from the Earth, hath been observed by Miners, who are often too sensible of Damps, which except timely prevented, make the Air so thick and muddy, as to put out their very Candles. And that the Thickness of the Air may contribute to the raising of the Mercury in the Pipe, appears from what hath been before observed in the Torrecellian Experiment. And since the External Air is liable to be altered so many ways, by the Mixture of insensible Corpuscles of Matter, its Rarity and Density are sufficient to account for the several Variations in the Height of the suspended Mercury; since accordingly as the Air is Rarified, its Pressure in Bodying up the Mercury must accordingly be varied. EXPERIMENT XIX. The subsiding of a small Cylinder of Water. TO try whether a Cylinder of Water would subside in our Receiver as the Cylinder of Mercury did, we filled a Cylinder of four foot long with it, which being inverted, and the lower end placed in a Glass Vessel, we let it down in the Receiver and closed it up; which being done, and the Pump set on work, we found that it did not in the least subside till such a Quantity of Air was exhausted, as to leave the included Air so much weakened in its Spring as to be worked upon, and overpowered by the weight of the Water; and then, upon every Suction, it sensibly subsided, tho' not so much as the Quicksilver; for whereas the Quicksilver subsided till it fell within an Inch of the Basis, the expanded Air remaining in the Receiver, was able to bear up the Water a Foot high. But the Experiment being tried in a small Receiver, the Quantity of Air included in that, coming nearer to an Aequilibrium with the Cylinder of Water, it sensibly subsided upon the first Exsuction; and much lower upon the second, and sometimes not much less than two foot; and the Water in this as well as the former, upon a reingress of Air risen to the Top of the Cylinder, but with more Speed than the former. EXPERIMENT XX. Conceening the Elater of Water. TO evince that Water hath, besides a notable one, a languid Elater, we filled a Glass Bubble with a long Neck, termed by the Chemists a Philosophical Egg, about a Span above the Bubble, with Water; where fixing a piece of Paper, we conveyed it into the Receiver, and found, that, after part of the Air was pumped out, the Water sensibly risen upon every Exsuction, the breadth of a Barleycorn; and upon the ingress of the Air presently subsided to its former place. Another Instance of the Air's Expansion, I obtained by filling a round Pewter Vessel with Water at a small Hole, which being stopped with Soder, and the Vessel bruised in several places, to compress the Water, the Vessel being perforated with a Needle, it spun out with Force enough to raise it a considerable height into the Air. EXPERIMENT XXI. Concerning the same. HAving filled a Glass Viol with Water, which contained something above a Pound, I took a Glass Pipe, about as thick as a Goose Quill; and having put one End of it into the Neck of the Bottle, and closed it with Cement, I filled the Pipe half full with Water, sticking a piece of Paper at the Superficies of the Water on the outside of the Pipe, which being placed in the Pump, after the Air had been pumped a while; above sixty Bubbles of Water as big as Pease risen out of the Water, one after another; and the Water in the Bottle so far expanded, as to rise quite up to the Top of the Pipe; and being permitted to subside, several Bubbles of Air risen out of it afresh, as soon as it renewed its Expansion as before; but upon a reingress of the Air, it presently subsided almost to the Bottom of the Pipe. Besides which, the following Phaenomena were observable: First, That those Bubbles, which ascended last, were much larger than the former, either, because their Parts were more expanded than before, or because more Bubbles of Air were united together, but whatever was the Cause of it, we observed, that they ascended much slower than before. Another thing to be observed was, that tho' Bubbles are usually wont to rise above the Surface of the Water, encompassed with a thin Film; yet, in this Tube, the Surface of the Water being Convex, the less protuberant Parts of the Bubble were covered with Water. Another Observation which occurred was, that whereas those Bubbles which risen at the Beginning of the Operation, divided the Water which they passed through, in their Ascent; these latter expanded Bubbles, filling up the Cavity of the Cylinder in their Passage, raised the Water before them; till the Air was again permitted to re-enter the Receiver, and then they wholly disappeared. From which Observations it may Naturally be inferred; First, Bodies under Water may be pressed upon by the Atmosphere, as well as incumbent Water; Secondly, It cannot be hence inferred, that the Intumescence of the Water proceeded from any Elasticity in it; since, it might more probably proceed from the Elasticity of the Air lodged in the Pores of the Water. And to make it probable, that those Bubbles proceeded from small Particles of Air, dispersed through the Pores of the Water, and not from any spirituous Parts of the Liquor expanded, I shall subjoin the following Experiment. EXPERIMENT XXII. The Bubbles proved to be Aerious, and not Watery, by observing the like Bubbles in î Mercury: To which is subjoined a Digression, whether the Air is generated de Novo, etc. THO' it be generally alleged, that the Bubbles which rise in the Cylindrical Tube, in the foregoing Nineteenth Experiment, are Particles of Water expanded, upon a Diminution of the Incumbent Weight of the Air; Yet I am apt to believe them really Parts of Air dispersed through the Water; because, upon the re-entering of the Air, the Water was not impelled quite to the Top, but was depressed, by the Air lodged above it, almost an Inch, which, being collected together, was able to resist the Pressure of the Air. The Bubbles which rise in Water, Aerial, proved. But in order to a further Discovery, whether the aforesaid Bubbles were Water or not? We tried the Nineteenth Experiment in a small Receiver, and upon drawing out the Air, the Water subsided; upon which, several Bubbles rising to the Top of the Cylinder, prevented the Rising of the Water, half an Inch, being possessed by the Bubbles of the Air, collected at the Top of the Cylinder: And we were further persuaded, that those Bubbles were Aerial, because the Air, being a second time exhausted, the Water contained in the Tube, was, by the Spring of that Air contained in the Cylinder, depressed below the Surface of the Water which was without the Tube, having a Convex Superficies, as Water exposed to Air in such Tubes usually hath, but rather more protuberant: And to demonstrate, that those Bubbles were really made up of Aerial Particles, when the Air was almost exhausted, and the Water had subsided near as low as the external Water, by applying Water to the Tube, which contained the Air, we observed that it was so far expanded, as to depress the Water down to the Bottom of the Tube, several Inches below the External Water: So that the Air, which was before expanded to near a hundred times its extent, was capable of being further expanded by Heat. But I was yet further confirmed in my Opinion, that those Bubbles were nothing but Air, lodged in the Pores of the Water, because the Air being exhausted out of the Receiver, the subsiding Water yielded not Bubbles as before, except a few small ones, when it was near pumped out. And what I took for a stronger Argument was, that the same Experiment being tried with Mercury, several Bubbles likewise risen to the Top of the Cylinder; and the Mercury subsiding a second time, upon the Exsuction of the Air, several Bubbles appeared in the Bottom of the Cylinder; which grew bigger and bigger as the Surface of the Mercury descended lower. From whence it appeared, that a Body, The Expansion of Water depends on the Elater of the Air lodged in its Pores. more ponderous than Water, might contain Aerial Particles in its Pores, capable of expanding themselves, when the Cause of their Compression is taken away; so that we have Reason to believe, that the Intumescence of the Water, not only in these Experiments, but also the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 of the Water, contained in the Pewter Globe before mentioned, proceeded from the Expansion of the Aerial Particles contained in the Pores of the Water, rather than from any Elasticity in the Water itself. These things being premised, it would be a Matter of some Importance, and of no small Consequence, Whether Air be a primogeneal bedy or not? to determine, whether what we have said of the Air be true, to consider whether Air be really a Primogenial Body, and inconvertible into Water, and Vice versâ, or not: But it being as difficult, as requisite, we shall rather choose to offer what may be urged of either the Affirmative or the Negative. And first, in favour of the inaptitude of Air to be turned into Water, or of Water into Air, it may be urged; that besides, that it hath been the Opinion of several Philosophers, it hath likewise been found impossible by Experience to effect such a Change in either of them; And the diligent Schottus Mecham. Hydraulicopneumat. Part 3. Class. 1. relates, that in the Musaeum Kircherianum, Water hath been hermetically sealed in a Glass with a long Neck, and kept there this forty Years, without undergoing any Change: Nor, indeed, do we perceive the least alteration in the Nature of Air, Hermetically sealed in Glasses for Chemical Uses, tho' it may acquire several Degrees of Heat in them: And it may very plainly be seen, that tho' Water is divided into smaller Parts, and raised in the form of Vapours, by Heat; yet it is so far from being turned into Air, that in Chemical Distillations, it falls down into the Receiver in the form of a Liquor. And likewise Volatile Spirits and Salts, tho' their Parts swim up and down in the Receiver for some time, yet the former presently condense into a Liquor, and the latter, into Salts. And further it may again be urged, that tho' the Parts of Water may be put in such an Agitation, as in some measure to counterfeit the form of Air, yet since the quick Coalition of those Parts into a fluid Form, argues the impossibility of giving them a due Texture, requisite to add to Air the Springiness observable in it; it is a strong Argument against the Possibility of effecting such a Change. And that a bare Motion and Agitation of Parts is not sufficient to add Springiness to a Body, appears from the foregoing Experiment concerning a piece of Match, included in our Receiver; where the Agitated Parts of Smoak, were by no means capable of hindering the Expansion of the Bladder contained in it. And tho' Josephus Acosta tells us, that Grates of Iron have been so much corroded in the Air, as to be turned into a Substance which would crumble into Powder like parched Straw; and tho' the Accurate Varenius hath observed in the Issands called Azores, that by the Sharpness of the Air even the Tiles of the Houses have been corroded; yet are they no Arguments, that such corrosive Humours may put on the form of Air; since such Phaenomena may be accounted for, by the Mixture of corrosive Steams mixed with it; which are so far from being endowed with the true Qualities of Air, that they may, notwithstanding they are mixed with the Air, retain their own Natures; which is evident in subliming of Sal Armoniac. And I have had a subtle Saline Body, which would not only rise itself, retaining its own Nature, but would also raise the Substance of Gold along with it, whose Parts would also retain their own Natures, and stick to the Top of the Receiver like pure Gold. I remember that once having tied a Bladder to the Neck of an Aeolipile, when the Water was forced out into it, so as to distend it, we slipped it off, and having tied it close, put it into our Receiver; where we observed, that upon the Exsuction of the Air, it was considerably expanded: And tho' the Bladder, when taken out of the Receiver, continued in the Cold for some time; yet the included Substance continued near as fully distended: But notwithstanding the Plausibleness of this Experiment, I could not but suspect, that the Distension rather proceeded from the Air, which upon the first working of the Aeolipile came out with it, than from any parts of the Water converted into Air. But to proceed to what may be alleged, to Countenance the Change of Water into Air; If a good Aeolipile be placed upon hot Coals, the Water will sometimes spring three or four foot high into the Air; and when taken off the fire, will continue to emit copious Streams: And if, when it is taken from the fire, almost empty, the Neck be immersed in Water, as soon as it gins to suck in Water, it will raise Store of Bubbles, which seem to proceed from Water too much expanded by the Heat of the Aeolipile; and if, when that Aeolipile is almost full of Water, a live Coal be held before the Neck, it will manifestly be kindled, by very vehement Steams which flow out of it, which will have the more powerful Effects, the nearer the Coal is held to the Mouth of the Aeolipile. But since by holding a Knife before these Steams, they will be condensed upon it into Water; and thence appear not so much to have acquired the Nature of Air as to have their Parts put into a violent Motion, I shall add a Relation from the Industrious Kircher, of a Famous Hudraulick Engine, See Figure the 15th. which he made by the Order of Innocent the Tenth. The Account of it, in his own Words, is the following, Cum eodem tempore quo haec scripsi, Summi Pont. Innocentii X. Mandato Organi Hydraulici in Horto Quirinali constituendi Cura mihi commendata esset, Aeoliam Cameram insigni sane Successu construi jussimus, ea quae sequitur Ratione. Erat Longitudo seu Altitudo Camerae (A H) quinque Pedum, Latitudine tres fere ex Lateribus, constructa, in Medio duo continebat Diaphragmata (C D) & (E F) in Modum Cribri pluribus Foraminibus pertusi. Paulò infrà Canalis (G) Aquam advehens inserebatur in (H) eidem Epistomium parabat Exitum. Aqua itaque per Canalem (G) maximo Impetu ruens vehementissimum Ventum mox intus excitabat; qui Ventus nimiâ Humiditate imbutus, ut purior ●xiret sicciorque Diaphragmata illa in Cribri Modum pertusa, ordinata sunt. Intra haec enim Aquae vehemens Agitatio, rupta fractaque Aerem puriorem per Canalem (A) subtiliorem emittebat: Verum cum postea inventum sit Aerem plus aequo humidum interioribus Organi Meatibus maximum Detrimentum infer: Hinc, ut Aer aquosus siccissimam Consistentiam acquireret, ordinavimus Canalem plumbeum (Q R) in Haelicem contortum Vasi (S) aliquantulum capaciori in modum Vrnae efformato, insertum. Intra Vrnam enim plumbeam & Canalem tortuosum illisus Aer humidus, ita ab omni Aquositate defaecabatur ut ex Furno in Organum derivatus dici potuerit. Vrna (S) Canalis tortuosi (Q R) ultimum Orificium (Z) inseritur Anemothaecae Organi. Et hunc Modum Organis Hydraulicis omnium aptissimum reperi. And I rather cite this Account, because it is delivered as Kircher's own Observation; and had I, when I was at Rome, taken notice of these Engines; and found that the Effluviae which blew the Organs, were not again condensed into Water, I should be apt to believe it not impossible to turn Water into Air; it being altogether impossible, That the Air lodged in the Pores of the Water, should supply so large a Quantity of Air, as is requisite to blow the Organs: I therefore was induced to think, that it might proceed from some Parts of the Water put into a very brisk Motion, since I had observed, as I passed betwixt Lions and Geneva, that the River of Rhone, being on a sudden straitened betwixt two Rocks, which are so near, that a Man may stand with one Foot upon one, and the other Foot upon the other, some Parts of the Water were put into so violent a Motion, as to be raised into the Air a considerable Height, and at a distance to appear like a Mist; tho' I must confess it difficult to conceive, how such Vapours should pass through a leaden Pipe of such a Length, since we see that Vapours are condensed into Liquids', in a much less time, in the Heads of Alembics, and the Necks of Aeolipiles, when once the Motion of their Parts are checked by Cold. But leaving this plausible, tho' not satisfactory Experiment, I shall proceed to another, which is this; Having filled a Glass Bubble, capable of containing about three Ounces, with near equal Parts of Oil of Vitriol and Water, half a dozen Iron Nails being cast into it, we stopped the Cylindrical Neck of the Tube with Diapalma, so close, as to exclude the Air altogether; which being done, we immersed the Neck of this Bubble into a Glass Vessel full of the same Liquor, and in a little time perceived Bubbles to rise to the Top of it, being raised by the Heat produced by the Action of the Oil upon the Nails; and this Air was so much increased, in a little time, as to depress the Water quite out of the Bubble into the Cylindrical Neck of it: But lest that Pressure should be thought to proceed from the Agitation of those insensible Parts of Matter, we observed, That tho' the Vessels were exposed to the Air for four days, to give the Motion of the Parts time to cease, had the Effect proceeded from them; we observed, That the Liquor, all that time, continued depressed, the Space beforementioned being filled with Air. And, what was worthy to be noted, Upon a small degree of Heat approaching the Bubble, the included Air was further dilated. And the like Phaenomena succeeded upon a Trial with Nails corroded in Aqua fortis; From which Experiments, it might be inferred, That if Water be not convertible into Air; yet it seems probable that it may be generated anew. And that Air and Water are mutually convertible into each other might further be urged, as nothing but what the Aristotelians teach and allow of. But we shall rather urge, That if what Democritus, Lucippus and Epicurus, together with other Naturalists teach be allowed of, viz. That the Qualities of Bodies depend on the different Figures, Shapes and Textures of the Parts of Matter, they consist of; it will be reasonable enough to think, That the Texture of the Parts of Water being altered, they may acquire the several Qualities of Air; since it is certain, That the Parts of Matter may, by a lucky Concourse of Causes, become springy: So Silver by being beaten with a Hammer acquires Springiness, which it loses by being heated in the Fire, and becomes flexible. EXPERIMENT XXIII. The Subject of the former Experiment prosecuted. IN Prosecution of what was delivered in the foregoing Experiments, We filled a Glass called a Philosophical Egg with common Water, about a Foot and a half high; it being large enough to contain about nine Ounces, and the Diameter of the Neck being, at the Top, half an Inch, and at the Bottom an Inch; this being put into the Receiver, and the Pump plied, when the Air was pretty well exhausted, several Bubbles risen to the Top and broke; but all of them finding an easy Passage through the Water, did not elevate it as when they ascended in a narrower Cylinder; but upon an Admission of Air into the Receiver again, the Water was sensibly depressed. To try whether distilled Water was more subject to expand than common Water; I put two Ounces of it into a Glass Bubble, which wrought to the Middle of its Neck; but it neither swelled nor yielded Bubbles upon an Exsuction of the Air. But having put distilled Water into two distinct Philosophical Eggs, the Neck of the former being straitened with a Glass Tube, we placed them in the Receiver, and found a manifest Difference upon the Exsuction of the Air; for in that which was straitened, the Air manifestly elevating the Water, several Bubbles were gathered about the bottom of the Glass Tube; whereas in the other Egg, the Water was not in the least elevated; and though the Bubble in the last-mentioned, disappeared upon the Re-ingress of the Air, those above the Tube continued visible, only a little contracted, for a considerable time; the Surface of the Water, which was before elevated, being depressed lower than when first put into the Egg. And after a days time having again plied the Pump, we observed, That the Bubbles were so much drawn out before, that we could scarce discern a Bubble in either; but that in which the Cylindrical Tube was placed, swelled the Breadth of a Barley Corn, tho' the other did not; yet, in the former, upon a Re-ingress of Air, it subsided again, and whether that Swelling was caused by the Rarefaction of the Water, or the Spring of some latent airy Parts, is not easy to determine. EXPERIMENT XXIV. The former Experiments prosecuted with other Liquors. HAVING put Salad Oil into a Glass about the Size of a Turkey's Egg, whose Stem was near ⅓ of an Inch in Diameter, the Liquor reaching up to the Middle of the Stem, we placed it in the Receiver, together with the like Vessel filled to the same Height with Water; and upon drawing out the Air, the Bubbles were not only more copious than those of the Water, but risen much sooner as well as longer, continuing till the Pumper was quite tired with Pumping; and what was very remarkable in this Experiment was, that when the Oil was put into the Receiver, before the Receiver could be closed, and the Pump put into Action, it subsided near half an Inch in the Stem. Having put Oil of Turpentine into a Glass Bubble, we observed, That it afforded a good Quantity of Bubbles, which expanded themselves in their Ascent, and would sometimes raise the Oil in the Tube so much as to make it run over. But besides the foregoing, we tried the like Experiments with other Liquors, amongst which, a strong Solution of Salt of Tartar afforded very few Bubbles, and those much later than other Liquors: Spirit of Vinegar likewise yielded very few. Red Wine afforded Bubbles pretty plentifully, which changed Places by moving in an obliqne Ascent, and form a sort of Froth near the Top, which presently disappeared: Milk afforded plentiful Bubbles, which elevated that Liquor more than common Water. We likewise put Eggs into the Receiver, to see whether the Substance contained in the Shells would break them; leaving the Film within it whole, as that Substance frozen had done; but it succeeded not. We put Spirit of Urine into a Glass Egg, filling another up to the Middle of the Neck with common Water; to which we added as much Spirit of Wine as raised it half an Inch higher; and into a Glass which differed from the former only in having a flat Bottom, we poured rectified Spirit of Wine, till it risen to ⅔ of the Neck: And the Edges of these three being marked, we put them into a Receiver. Upon the Exsuction of the Air the Mixture of Water and Spirit of Wine afforded very few Bubbles: The Spirit of Urinal swelled near an Inch and a half above the Mark, affording Store of Bubbles, which form a Froth, upon which several larger Bubbles lay, which were placed one above another, to the Top of the Tube: The Spirit of Wine afforded Bubbles till we were weary of pumping, which ascended very swiftly, and immediately disappeared at the Top, first lifting up the Surface of that spirituous Liquor so as to form a thin Film. And it was further observable, That the Motion of these Bubbles in their Ascent, was in a straight Line; whereas those of the Water and Wine made a Line, which on each side appeared like the Teeth of a Saw: And lastly, in this Spirit we took Notice, That the order which these Bubbles ascended in, was in Lines parallel, and of an Equal Distance from each other; the Bubbles likewise following each other, in such an order, as to form a sort of Bracelet, one end of which seemed to rise from a certain Point at the Bottom of the Glass. When Air returned into the Receiver, the Bubbles on the Spirit of Wine gradually subsided; yet neither that, nor the Mixture of Water and Spirit were depressed below the Mark: But the Spirit of Wine continued expanded, near half an Inch, which I found to succeed upon several Trials. EXPERIMENT XXV. Concerning the Air's Gravity, and Expansion under Water. HAving filled a Wide-mouthed Jar, with about half a Pint of Common Water; we sunk two Glass-Viols, whose Shape and Size is represented by the Eighth Figure, one of which contained just so much of a Ponderous Mercurial Mixture, as was requisite to sink it, when covered with white Wax; the other being weighed down by Water, and the Mouths being downwards; the Quantity of Water contained in the former, filling three Parts of four of the Glass, the Air contained in the latter being equal in Dimensions to a Pea. These being let down into the Receiver, upon plying the Pump, at the last so many Bubbles risen up to that which swum upon the Water, as were able, by expanding themselves, to cause some of the Water to fly out, and make the Viol emerge to the Top of the Water contained in the Jar; where at every Exsuction it continued to expand, till it was able to raise up the side of the Viol, and in part to evacuate itself; upon which it presently swum upon the Water, as before, and eight times after discharged a Bubble of Air about the Size of a Pea; but, when we permitted the Air to enter in again, it presently subsided to the Bottom. As for the other, it continued at the Bottom all the while. But some time after, the Pump being plied, it raised itself considerably; but about sixty Parcels of Air as big as Peas, finding vent, and getting out, it presently subsided; tho' upon a further Expansion of the Air, it risen again, and subsided, which successive Ascent and descent, it continued Nine times after after the Pump ceased working; but when the Air was again let in, it was presently fixed at the Bottom. From which Experiment, that Hydrostatical Rule, That a Body will swim in the Water, if it be lighter than its equal Proportion in Bulk, will appear to be likewise true, when the Weight of the Atmosphere is taken off. EXPERIMENT XXVI. Concerning the Vibrations of a Pendulum. IT being usually taught, That the Motion of a Pendulum is something quicker, accordingly as the Medium it moves in, is thinner; we suspended one, which weighed about twenty Drachms in our Receiver, fixing it to the Cover by a piece of Silk; and having fixed another of an equal weight without the Receiver, we gave them both an equal Motion, and observed, that whilst the Latter made twenty Vibrations, the Former counted twenty; but the Pendulum, being afterwards put into Motion in the exhausted Receiver, and likewise in the same Receiver, before it was exhausted, continued its Vibrations to an equal space of Time in both; so that from what we could observe, the Difference of the Vibrations in Air, and that more rarified Medium, viz. the exhausted Receiver, was scarce sensible. EXPERIMENT XXVII. Concerning the Propagation of Sounds. IT hath been the received Opinion of the Schools, That the Air is the Medium, through which Sounds are conveyed: But the Industrious Kircher having observed, that if a Bell be fixed in the upper end of a Tube, and, upon making the Experiment de Vacuo, be left there, a Loadstone applied to the side of the Tube, will attract the Steel-clapper; which, upon a Removal of that Loadstone, will fall upon the other side of the Bell, and cause an Audible Sound: He thence infers, That the Medium through which Sounds are conveyed, must be much more subtle than the Air. But to evince the contrary, we suspended a Watch in our Receiver, by a Packthread, and observed, That the Sound was not only audible at the sides of the Receiver; but that that which was likewise perceived by the Ear, held near the Cover, was different from that which we heard at the sides of the Receiver; but the Air being drawn out, we could not perceive the least Sound, tho' the Motion of the Minutes assured us, that the Pendulum continued its Motion; yet upon admitting of Air again into the Receiver, the Sound was again renewed; which Experiment seems to evince, that the Air is the Chief Medium, through which Sounds are conveyed: Yet it is not a little strange, that so slight a Stroke as that of the Pendulum, should give such an Impulse to the Ambient Air, as to enable it to communicate a Motion to the sides of the Receiver, strong enough to put the External Air into an Undulating Motion. But having supported a Bell in the Middle of our Receiver, by a large Stick, which reached from one side to the other, the Diameter of the Bell, being about two Inches, we observed, that tho' the Sound in the Receiver, was not equally as sharp as in the open Air; yet there was no considerable Variation, when the Air was drawn out; which evinces, that a subtler Medium than the Air, is not altogether incapable of propagating Sounds, no more than Air; however, in the foregoing Experiment tried with a Bell, suspended in a Glass-Tube, it may not without Reason be suspected, that the Cavity of the Tube was not wholly void of Air, since Experience informs us, that it is impossible to fill the Glass-Cylinder, so as to keep the Upper Part of the Tube void of Air, since the Airy Parts lodged in the Pores of the Mercury, fly up into it. And further on this Occasion, to show how far the Air is the Principal Medium of Sounds, we might allege, that it was observable in a former Experiment, that tho' upon the striking of Fire, with the Lock of a Pistol in our Receiver, the Sound is audible; yet it is much more dead, than when made in the open Air: And the like Variation is observable in all other Sounds made in our Receiver. EXPERIMENT XXVIII. The Eruption of Bubbles from Water, upon the removal of the Air. FOR a further Confirmation of what hath been delivered in the XXth Experiment, viz. That the Air included in our Receiver, makes as strong a Pressure upon Bodies encompassed by it, as if they were exposed to the Pressure of the Atmosphere; we put a Viol, filled with Water, and well stopped, into our Receiver; and, upon an Exsuction of the Air, found no sensible Alterations; but another, which was not so close stopped, being put in, we observed that the Air included in the Bottle, upon the Surface of the Water, making its way out, several Bubbles presently appeared in the Bottom of the Water: from which Trials, it appears, That whilst the Air was included, the Water appeared as if pressed upon by the Atmosphere. But in order to a further Prosecution of our Design in this Experiment, we filled a Glass-Egg with Water, and suspended it by a String to the Cover; so that, by turning the Glass-stopper in the middle of the Cover, we so screwed up the Neck of the Egg, as to break it, and thereby make way for the Exclusion of the Air; upon which a number of Bubbles presently risen in the Water, so as to represent a Shower of Rain inverted. But this Experiment may be tried with less trouble, in one of our little Receivers, where the Exsuction of the Air is more expeditious. In one of which the Experiment being made with red Wine, instead of Water, it appeared immediately frothy, like Bottle-Ale, tho' opened less cautiously. EXPERIMENT XXIX. The reason of the Ascent of Fumes and Vapours. TO show, whether the Ascent of Fumes and Vapours, was rather promoted by the Ambient Pressure of the Air, than that their Ascent depended on their own Positive Lightness; I conveyed a Certain Liquor which I had formerly made for other Purposes, into our Receiver; it consisting of Metalline Ingredients, which upon Unstopping of the Bottle, would emit copious Steams, like the Powder of Alabaster; but upon stopping of it again, the Upper Part of the Bottle, as well as the Liquor, became Transparent; and this Liquor being conveyed into our Receiver, with a Weight affixed to the bottom of the Viol, to keep it from rising up, when the Cork was pulled out, we tied a String to the Cork, and the other End to the Receiver; and having closed it up, and pumped out the Air, we screwed the Cork out of the Bottle, and observed, that tho' some Parts of the Air included in the Bottle, raised a few; yet the Fumes did not rise as when exposed to the open Air, but lifting up themselves by their own Agitation, risen to the Top of the Viol, and no higher, but ran down the outside of the Glass in Streams; which continued till the Ingress of Air was permitted to put a stop to that Phaenomenon; but as soon as the Bottle was taken out into the open Air, Fumes plentifully risen as before: From whence it appears, that Steams in a Medium thinner than themselves, may tend downwards. EXPERIMENT XXX. The Nature of Fluid Bodies illustrated by Smoak. TO show how much the Ambient Atmosphere, emulates the Nature of a fluid Body; We enclosed a light Match, in our little Receivers; and when it was filled with Smoke, we took the Match out, leaving the Smoke behind, closing the Receiver again, to keep it from flying away; upon which, we observed, that the Smoke settling itself in the lower Part of the Receiver, so far emulated a Fluid, as to change its Horizontal Superficies, as the Glass was variously inclined. As also upon a more violent Agitation of the Vessel, it was put into a Vibrating and Undulating Motion, as Liquids' usually are, which it lost again by degrees. When the Key of the Stop-cock was turned, Part of it would flow out like Red Wine, out of a Bottle, when the Neck is inverted and immersed in Water; the Air gradually ascending into the Receiver in its Room: Besides which Phaenomena it was remarkable, that a hot Iron being held near one side of the Vessel; the Smoke was presently raised in a Stream up to the Top of the Receiver, keeping distinct Superficies, from the Air included in the Receiver, yet nevertheless upon a Recess of that Heat, it would again subside. And these things being considered, as likewise that there is a manifest Difference in the Weight of Proportionable Quantities, as to Extension, of other Liquors, it may not be absurd to mention the Atmosphere, amongst others Liquids; especially since, besides what we have already taken notice of, we may rationally suppose, that there are several Inequalities upon the Borders of the Atmosphere, as well as upon the Surface of that Smoke; since the Inequalities of its upper Superficies are not altogether indiscernible, if we look upon the Setting-Sun, with a good Telescope; for by that means, we may perceive the Surface of it rough, with several Inequalities, which curl along like Waves in the Sea. EXPERIMENT XXXI. Concerning the Cohaesion of Flat Bodies. TO try the Strength of the Air's Spring, when rarified, in a great Measure, by Exsuction, in our Receiver; we tried an Experiment, formerly more fully taken notice of, with two flat polished Marbles: For having fastened a Weight of about four Ounces to the lower, and wet the flat Superficies of them with Spirit of Wine, to keep the Air from getting betwixt them, we put them into our Receiver, and found that the Spring of the Air, after several Exsuctions, was strong enough to bear up the Under-stone, and to keep it from falling. And how strong the Cohaesion of Flat Bodies may be, we have a Notable Instance related P. Nic. Zucchius, apud Schot. Part. 1. Mec. Hydraulopneum, who says, Juveni lacertorum suorum robur jactanti proposita semel est laminea aerea, per ansam in medio extantem apprehensam elevanda è Tabula Marmorea, cui optimè congruebat: Tum instantibus amicis manum utramque admovens, cum luctatus diu harentem removisset, excusavit impotentiam objecta peregrini & potentissimi glutinis Interpositione, quo fortissimè copulante nequiret divelli; donec vidit ab alio per tabulam facillimè laminam deduci, & ad extrema productam, & actam in transversum inde deportari. But to make it evident, that two Bodies may stick together, by having their Surfaces Contiguous only in a small Compass, I shall subjoin an Experiment made in our Receiver. EXPERIMENT XXXII. The Pressure of the outward Air, on a Valve fixed to the External Orifice of the Stop-cock. HAving exhausted our Receiver, and taken it off the Pump, we applied a tapering Valve of Brass, such as the Ninth Figure represents, the taper End being put into the Orifice of it, and the Chink betwixt the Stop-cock and the Glass, being filled up with Diachylon. To the lower Superficies of the Door of that Valve, was fixed a Button, to which a Scale was hung, to hold Weights in; and then, the Key of the Stop-cock being turned, the Atmosphere made such a strong Pressure to get in, as to keep the Valve close to the Orifice, till a considerable Weight was put into the Scales, and then the Weight of the Atmosphere being overpowered, it was presently drawn down. In which Experiment it was to be observed, That tho' the Receiver was but moderately exhausted, and tho' it leaked considerably; yet the Weight supported by the Pressure of the Atmosphere, amounted to ten Pound: Nor indeed is it strange, that its Pressure should be so considerable, if we do but think, how large the Cylinder of Air, that recoiling from the Ground, presses against it, is, being extended to the utmost Superficies of the Atmosphere. EXPERIMENT XXXIII. Concerning the Pressure of the Air against the lower superficies of the Sucker, what Weight will draw it down, and how much it is able to raise. A Discourse concerning the Nature of Suction, etc. The weight of the Atmosphere considered. TO compute more exactly the Weight of the Incumbent Atmosphere, we impelled the Cylinder to the Top of the Pump, taking off the Receiver, and fixing just such a Weight to one of the Teeth of the Sucker, as was able to bring it down to the Bottom of the Cylinder; which being done, and the Sucker impelled up again to the Top of the Cylinder, the upper Orifice of it was exactly stopped; and a pair of Scales being fixed to the Iron-Sucker, by casting in so many Weights, as were able to draw down the Sucker, we were truly informed of the Weight of a Pillar of the Atmosphere of an equal Diameter with the Boar of the Cylinder. By which Method we found, that the Sucker, which required 28 Pound of Lead to draw it down, was not drawn down with less than the Addition of an hundred Pound, when the upper Orifice of the Cylinder was stopped; tho' upon turning of the Key of the Stop-cock, and letting in Air, it would readily fall without that Weight; which was an Argument, that the Descent was hindered by the Pressure of the Air, which buoyed up against the lower Part of the Sucker. What weight the Atmosphere is able to raise, suspended at the Sucker. This Experiment being tried, and the Sucker being forcibly drawn down to the Bottom of the Cylinder, whose Diameter was about three Inches; the Pressure of the Atmosphere was so considerable, as to be able to raise above a hundred Pound weight; besides the weight of the Sucker, which was not a little admired by the Standers-by, because they saw no Force used to lift it up. And tho' by such Trials we may not be able to discover exactly the weight of the Atmosphere; yet, as a Famous Poet says, Est quoddam prodire tenus, si non datur ultra. But were this Experiment Tried at several Seasons, in the Year, and in several Climes, as well as in Cylinders of a different Diameter, it might render our Guesses more certain as to the Height, and Gravity of the Atmosphere, and whether it varies considerably at such distant times: For the Place where the Foregoing Experiment was tried, was about 51 Degrees Latitude, being tried in the Winter, and about the Change of the Moon. But, not to spend so much time, as would be taken up with all the Reflections, that might be made on the Foregoing Experiment; I shall consider some few Inferences, which may be drawn from them. And First, From the Rising of the Sucker, and the Weights fixed to it, we may call in Question, what some teach concerning Suction, viz. That there is a sort of Endeavour, to draw the Body sucked, in the Parts of that Body which is said to suck; for tho' when we suck a thing with our Mouths, there is a Manifest Endeavour of our Mouth to draw the Body sucked; yet the Cavity of the Cylinder is not so disposed by any Endeavour in the Glass-Tube. Nor can the Ascent of the Sucker be attributed to any sucking Force of every Part included in the upper Part of the Cylinder, since it appears not, how such Airy Particles should be hooked in the Pores of the Sucker, or how they should be able to raise such a Weight: Nay, that those Particles of Air do not draw it up, is further evident; since by admitting more Air in, that supposititious sucking Quality is diminished, and not increased: And for the same Reason it is evident, that it cannot proceed from a fuga Vacui; for there is the same Reason for an Endeavour to prevent a Vacuum, tho' a little more Air be let in, as there was before; since there still remains a Vacuity. Nor can the weakened Attraction, upon letting in of Air, be attributed to the Resistance of the Vacuity, but rather the Spring of the included Air; since when in the former Experiment it was plain, that the rising of the Sucker and Weights, was not obstructed by the Cavity of the Cylinder, when void of Air. Considerations concerning a Vacuum. But to proceed: From hence further we may be directed, what to think of Nature's Abhorrency of a Vacuum, which hath been so long held as an Axiom in the Schools: For besides, that the Insensible Parts of Matter, can neither have Sense to perceive any ill consequences in the Universe, which would ensue a Vacuum, nor be able to know how as Intelligent Parts of Matter to prevent it; (for if they did, Nature may be said in a great many Cases to act very irrationally to effect her Designs, since in the XXXIId d Experiment, instead of rushing into the Receiver, she less cautiously raised up the Valve, and kept herself out. But, I say, besides the Insensibility of Matter, it may farther be urged against that Axiom, that the Endeavour which those Bodies may seem to have, rather is to fill than to prevent a Vacuum; since upon the drawing down of that Valve, the Air which rushed in, could not prevent what was already in Being. Besides in our XIXth Experiment, it might be demanded, Why the Water which descended into the Tube, upon the Exsuction of the Air, did not rather keep its place to prevent a Vacuum, or why for the same Reason it did not ascend before the Re-ingress of the Air. Moreover, the Air may rather be said to rush in again, as being impelled by the Spring of the Neighbouring Air, than a Design to fill the Vacuities, since from our XVIIth Experiment, it appears, That when the Receiver was supposed to be full, we could by the help of the Sucker, find the Spring of Subsequent Air impelled by it, still force more into it; and even in Windguns it is manifest, that the Air compressed as much as it is in our Receiver, may be squeezed into half the Room. And from the foremention'd Experiments, it may further be deduced, That the Reason, why Metaphorically speaking, Bodies may seem to forget their own Natures, to shun a Vacuum, seems to consist in this, viz. that the Weight of the incumbent Water, or the Pressure of the subjacent Air were not strong enough to press down or buoy up one another; for from our Nineteenth Experiment it appeared, that when the Pressure of the Air was taken away, the Weight of the Water itself was sufficient to make it subside, though it left no Air behind it: But further, from this last mentioned Experiment it appears, that it is possible, Even by Weights, to measure how far Nature is disposed to prevent or fill Vacuities; since a small difference in Weight determined, by depressing or permitting the Sucker to rise, how far Nature's Abhorrency of a Vacuum depended on the Causes we have so often mentioned. But here it may be requisite to advertise, that by Vacuities, I do not mean Spaces altogether void of Matter, but void of such as may be perceived; so that I take the Word Vacuum in the Common, not the strict and Philosophical Sense of the Word. But lastly, from this XXXIII Experiment it appears, that the Weight of the Atmosphere we live in, is stronger than what Men usually think it is; And probably, near the Northern Pole, it is much stronger: Since, if what Varenius observes, the Air is so condensed in Nova Zembla, as to hinder the Motion of a Pendulum, except moved by a heavier Weight than what is usually made use of in our Climate. EXPERIMENT XXXIV. Attempts to weigh light Bodies in our Receiver. TO try whether the Aequilibrium of two Bodies, of an equal Weight in the Air, but of unequal Dimensions, would be lost in our Receiver, as it usually is in Water, by Reason of a greater Quantity of Water buoying up against that whose Dimensions are most extensive, I took a Bladder half full of Air, and tied it to one end of our Balance, which turns with the 32 part of a Grain; which being counterpoised with a Weight in the other Scale, we let it down into the Receiver, and having closed it up, upon an Exsuction of the Air, we found the Bladder to dilate and manifestly to preponderate; but upon admitting the Air into the Receiver again, the Bladder was over-poised by the Weight; but leaving them in the Receiver all night, the Bladder imbibed so much of the External Moisture, as to weigh that end of the Balance down a good way; yet the Bladder being dried a little, they were both brought to an Aequilibrium: And the like Experiment we tried with a piece of Cork instead of the Bladder, and observed, that, the Receiver being Evacuated, as well as upon a reingress of the Air, the Cork manifestly preponderated. EXPERIMENT XXXV. Of the Cause of Filtration, and the Rising of Water in the Syphons, etc. The Cause of Filtration. TO try whether in Filtrations the rising of the Water might not proceed from the Impulse of the Air; we made use of a Syphon of Glass, represented by the Third Figure, which is made of two straight Pieces, and a crooked one, which joins the other two together, the Junctures being well closed. The longer Leg of the Syphon was pervious only at the small End, so as to suffer the Water to pass through it; but both the ends of the shorter Leg were equally pervious, the Diameter of their Boar being ¼ of an Inch. The length of these two Pipes was about a Foot and a half, that the Rarified Air in the Receiver, when it was pretty well exhausted, might not raise the Water included in the Pipe too high. The shorter Leg of the Syphon being immersed two or three Inches in a Vessel of Water, the other end was fastened to the Cover; which things being done, and the Receiver closed up, we began to pump. The Result of which was, that the Water dropped out of the lower Leg of the Syphon, as if it had been exposed to the open Air; till the Receiver was in some measure exhausted, and then several Bubbles rising in the Water, gathered together at the Top of the short legged Syphon, where expanding themselves, they stopped the Course of the Water; that in the longer Leg being suspended in the Tube and ceasing to drop; and the Water in the shorter Leg, was so far depressed, as not to be above a Foot high: But as soon as the External Air was let in again, it entered in at the small Orifice of the longer Tube; and, ascending through the Water contained in the Pipe, joined with the former, which was lodged in the upper Part of the short legged Tube. But, to prevent what Inconveniences ensued the rising of these Bubbles, the two forementioned Tubes, were placed so, as to meet in the middle of a Glass Viol., the Neck of the Viol being closed up with Cement; and the Tubes being thus fixed, and they, as well as the Viol, filled with Water, the Syphon represented by the Fifth Figure was placed in the Receiver with its shorter Leg in a Vessel of Water, upon which the Pump being plied, the longer Syphon continued to drop much longer than before; but at the last, the Bubbles which risen in the Pipes, were so dilated in the Viol, as to press down into the Ends of the Tube, and interrupt our Experiment, tho' what we observed gave us Reason to believe, that the Air contributed to the Motion of the Water through the Syphons. And here, I shall subjoin, that I once had a very slender Pipe, which when held upon the Surface of the Water in a Perpendicular Posture, the Incumbent Atmosphere pressed so much more on the Surface of the External Water, than that contained in the Tube, that the Water was raised in the Tube; and this Pipe being bend into a Syphon, and placed with the shorter Leg in Water as Syphons' usually are, the Water, of its own accord, risen up in the shorter Leg, and ran down the other; and this Syphon being placed in our Receiver, to try what Alteration of the Phaenomenon would appear there, we could not discern any sensible one. But tho' in this Tube just now mentioned, the Water rises of its own accord; yet, if such a Tube be thrust a little way into the Mercury, instead of rising, the Mercury in the Tube will be below that which is without it. EXPERIMENT XXXVI. The Weight of Air in the Exhausted Receiver. The subtle penetrating Power of some Spirits above that of the Air. The Cause why Air will not enter the Pores of some Bodies which Water will. The Weight of the Air, examined by an Aeolipile. The Proportion betwixt the Gravity of Air and Water: Betwixt Water and Quicksilver. Conjectures concerning the Weight of the Atmosphere. The Weight of the Air. NOtwithstanding the several Methods proproposed by Galileo, and others, to try the Weight of the Air; being willing to be further satisfied, we caused an Oval Glass with a small Tube at one End to be blown at the flame of a Lamp. And this Glass Bubble, being of the size of a Hen's Egg, was fixed to one End of a Balance, being counterpoised by a Weight at the other End, which being suspended in our Receiver, and the Pump set on work, the Bubble, after three Exsuctions, continued to preponderate more and more, till the Air was let in again, and then the Balance was reduced to its former Aequilibrium. But having repeated the Experiment with an additional Weight of three Quarters of a Grain, in the Scale opposite to the Bubble, the Weight of the Air included in the Bubble brought the Balance to an Aequilibrium, when the Air was drawn out; which Aequilibrium was again lost upon a reingress of it; so that had the Air been wholly exhausted, the Air contained in the Bubble might probably have weighed a whole Grain; and to prove that the Weight of the Air did really depress the Balance to which the Bubble was fixed, we exhausted the Receiver when the Neck of the Bubble was open; and did not perceive that End of the Balance in the least to preponderate: But a Lamb's Bladder being equally poised with a correspondent Weight, manifestly weighed down the Balance, though the Air included in it, was considerably expanded when the Air was pumped out of the Receiver. The Penetrating power of some Spirits above that of the Air. But once having caused the Pump to be plied longer than ordinary, the Air contained in a Glass Bubble expanded itself so powerfully, as to cause the sides of it to fly in pieces; which is a strong Argument of the Closeness of the Pores of the Glass, which are too fine to permit the Air to pass through them. And for a further Proof of the imperviousness of Glass, even by so minute Particles as those of the Air, I shall add; that in all the Trials I ever made, I but once found that a Spirit whose Parts are much more subtle and volatile than Air; I say, I but once found that a Spirit drawn from a Substance abounding with volatile Salts, and subtle Spirits, made way through the Pores of the Receiver, which unusual Phenomenon probably depended on the brisk Agitation of those spirituous Parts, increased by the more than ordinary Heat with which they were raised; for the Motion of them was so violent, as to fill the Receiver, and almost burst it with their impetuous Steams; so that the Pores of the Glass being opened with the violent Heat, several of them penetrated those Pores, and appeared on the outside of the Glass. Why the Parts of the Air are more indisposed to pass through the Pores of some Bodies than others. But tho' by some, the Particles of the Air are thought to be able to penetrate Glass; yet by others, they are thought to be Grosser than Water; since from the following Experiment it appears, that Water is capable of penetrating Bodies, and of being compressed into their Pores, which Air is not: For having conveyed a small Bubble of Water into the longer Leg of a Syphon, whose Orifice was as small as a Pin, that Air being incapable of passing through so small a Poor, kept the Water above it, suspended in the Tube; but as soon as that Bubble, by blowing into the wider Orifice of the short Leg, was compressed and squeezed out, Water passed through that small Orifice without any other force than the Weight of that which lay upon it. And the Inability of Air to pass through such Pores, which Water will readily enough, will be further evinced, by holding Water in a Tube, the lower End of which being very narrow, and perforated with a Poor no longer than a Hair; for the Water will readily pass through it; but if the Tube be inverted, the Water in the narrower End of that Pipe will be suspended, as if the End were wholly unperforated; the Air not being able to get through so small a Passage: And that Water will pass through Pores, which Air will not, may be further evinced, by putting a little Alkalizate Salt into a Lamb's Bladder; for by wetting the End of the Bladder on the outside, the Water passing through its Pores, will presently dissolve that Salt. The force of the Air's Expansion. But to return to what we have hinted before, concerning the Expansion of Air in a Bubble, so violently, as to break it; the Learned Jesuit Cabaeus says, he saw a Pillar so thick, that three Men could not grasp it, and that 1000 Yoke of Oxen could not tear it in Pieces; yet the Air included in the Crannies of it, so violently expanded upon the burning of a Fire near it, that it flew in pieces, tho' the Pillar was made of so solid Stones as Marble. And as for the Reason why sometimes the Bubbles included in our Receiver, did not break as at others, it probably proceeded from the Air's Expansion by Heat, when they were sealed, the included Air, upon a Removal of that Heat, contracting itself, and losing part of its Springiness; but this Guess we cannot wholly rely on. But, The Weight of the Air. To determine more exactly the Weight of the Air, we heated an Aeolipile of Copper, as hot as we could conveniently; and removing it from the Fire, we stopped the Neck with hard Wax, to keep out the Air; which being Weighed, when cold, counterpoised six Ounces, six Drachms and Thirty nine Grains; but the Air being permitted to rush in, by perforating the Wax with a Needle, the Aeolipile and Wax balanced an additional Weight of 11 Grains; so that the Weight of so much Air as filled the Cavity of it, weighed half a Scruple and a Grain. And tho' Mersennus affirms, that he had rarified the Air to seventy times its Bulk in an Aeolipile, yet I must confess it seems impossible to me, except the Metal his were made of, would bear a much greater Degree of Heat, without melting, than ours would, to rarify, and expel the Air contained in them: Besides, the Method he took seems much less exact than ours, since he weighed the Aeolipile whilst hot; which might throw off a Considerable Quantity of Scales, as we have often observed; the Weight of which, in weighing so light a Body as Air, might be considerable. Proportion betwixt the Weight of Air and Water, etc. As for the Difference in the Weight of an equal proportion of Air and Water, tho' Ricciolus and Galileo have, by different Methods, made very different Computations; and Mersennus hath asserted it to be as 1300 to 1. Yet by the most accurate Computation we could make in our Aeolipile the difference appeared to be, no more than as 1 to 938. I shall not wholly reject what Mersennus relates, but rather endeavour to reconcile the Difference, by representing, that my Observations were not only made in this Climate in London, where it is much colder than at Paris; but also at a time, when the Air was condensed by the Winter's Cold; at which time it may be supposed to be a fifth Part heavier than at Paris, when Mersennus made his Observations. Wherefore it would be of no small use, to make such Observations in several Countries and at several Seasons of the Year. Conjectures concerning the Height of the Atmosphere. Having said thus much about the Weight of the Air, it may perhaps be expected, that I should, by the Assistance of the Observations already delivered, determine the Height of the Atmosphere, from whence the Pressure of the Air proceeds: But tho' it may be no difficult Task to show, that the Accounts given by others are false; yet it is not altogether easy to determine a Controversy, in which the Truth is so hard to be assigned; and therefore, I shall only lay down something in order to the Elucidation of it. And first, it is necessary to take Notice, that the Weight of an equal Proportion of Air and Water about London is agreed on to be as 1000 to 1. In the next place it will be requisite to consider, the Difference in Weight, of an equal Proportion of Air and Quicksilver; to discover which, I took a Glass Pipe, such as is represented by the Sixteenth Figure, See Plate the First. which being partly filled with Quicksilver, and held in such a Posture, that the Superficies of the Quicksilver in each Leg was in a Horizontal Line, E. F. I. poured Water into one Leg, till it was filled up to the Top, by the Weight of which, the Surface of the Mercury was weighed down from E. to B. the Surface of the other being raised from F. to C. so that measuring the Height of the Tube of Mercury D. C. which was buoyed up by the Water in the other, we found it to amount to 2 13/54 Inches; the Height of the Cylinder of Water B. A. which counterpoised the Mercury being 30 45/54 Inches, and the whole Numbers with the Fractions, being reduced to improper Fractions of the same Denomination, the Proportion was as 121 to 1665, or by Reduction, as one to 92/121. Besides this, we took another Method, to discover the Proportion of these two Liquors, by weighing them in a Glass Bubble; by which we found, that it was as 1 to 13 19/28; and because Spirit of Wine is usually esteemed the lightest of Liquors, and Quicksilver the heaviest, I weighed that likewise, and found the Proportion of Quicksilver, and it, to be as 1 to 16 641/1084. So that the difference betwixt Spirit of Wine and Water was as 1 44/171; And here it may be necessary to observe, that I the rather weighed these Liquors in a Bubble; because, when they are weighed in open Vessels, the Protuberant Surface of the Mercury, and the Concave of the Water, makes it a difficult Matter to proportion them exactly, if the Superficies be large. The Weight of an equal Proportion of Air and Mercury. But to return to the Atmosphere. Having laid down the Proportion of Air to Water, and of Water to Quicksilver, it will be no very difficult thing to find, the Proportion betwixt Air and Quicksilver. And since from the Torrecellian Experiment, it appears that the Cylinder of Mercury is buoyed up by the Pressure of the Air, it consequently follows, that the Proportion of Air to Quicksilver is as 14000 to 1; so that a Cylinder of Air, that is able to buoy up Mercury two Foot and a half, must amount to 35000 Feet of our English Measure, or seven complete Miles; supposing the Air to be equally compressed above, as here below; but this Computation is not to be accounted so exact, since not only Seneca Nat. Quaest lib. 4. cap. 10. says, Omnis Aer, quo propior est Terris hoc crassior; quemadmodum in Aqua & in omni humore Faex ima est; ita in Aere spississima quaeque desidunt, but it likewise is a Consequence of the Air's Spring; since it must needs be considerably compressed by the Weight of what lies upon it; besides, if we consider, that the Air may be expanded by Heat, to near a hundred and fifty times its Bulk, it may not be improbable, but that the utmost extent of the Atmosphere, may reach to some Hundreds of Miles. And this Conjecture may enable us to guests at the Height to which some Vapours may ascend, allowing what Emanuel Magnen a diligent Mathematician observed at Tolouse in a clear Night in August; for as Ricciolus records it, Vidit ab Horâ undecimâ post Meridiem usque ad mediam Noctem Lunâ infra Horizontem positâ, Nubeculam quandam lucidam prope Meridianum fere usque ad Zenith diffusam, quae consideratis omnibus non poterat nisi à Sole illuminari; ideoque altior esse debuit tota Vmbra Terrae: And the same Author further says, Addit simile quid evenisse. Michaeli Angelo Riccio apud Sabinos versanti, nempe viro in Mathesi Eruditissimo. But to conclude; It would be of no small Use in estimating the Height of the Atmosphere, were Observations of the Density and Rarity of the Air made upon several Parts and on high Mountains; but till by some Means or other, we can arrive at some degree of Certainty, as to the various Degrees of its Rarefaction above, it will be a hard Matter to determine the Height of it. EXPERIMENT XXXVII. Concerning Flashes of Light in the Receiver. AT the first when our Engine was made, we observed, upon drawing down the Sucker, and turning the Key, several Flashes of Light in the Receiver; which would not appear, if the Window which faced Northward were darkened; and this Phaenomenon depended on so unknown Causes, that upon often repeated Trials, I found, that sometimes it would appear and sometimes not; though for as much as I was able to perceive, there was not the least Difference in the Circumstances of these Trials; which made it difficult to bring our Observations to any Rules about it, or to frame an Hypothesis to Account for the Cause; tho' the Validity of some Conjectures that have been made may be afforded by the following Trials and Observations. For, First, We found, That the Phaenomenon might as well be exhibited by a Candle-light or Daylight, and however situated, so that the Rays of Light could but fall upon the Receiver. Next, The Flash appears just when the Key is turned to let the Air out into the Cylinder; but the same Phaenomenon would appear in a small one upon drawing the Sucker hastily down, tho' the Key was turned before; and it was further to be observed, That the Flashes, which appeared when first the Receiver began to be exhausted, were much stronger than when it was further evacuated. And it was besides observable, That when the Experiment was made in the small Receiver, and the Sucker had not been long before well oiled; the Oil, upon the drawing of it down, being put into Agitation, and divided into small Parts by the Attrition of the Pump, would rise into the Receiver like Smoke; which would likewise flow out of the Valve, when it was opened on purpose; and these Fumes, if the Glass was held in a light Place, would in some Measure appear luminous. And what was further to be admired, was, That when the Flash was considerably great, upon the Disappearance of it, the Receiver would become opacous, leaving white Steams upon the internal Superficies of the Receiver. And now if it should be asked, Whence all these Phaenomena proceeded? We should propose the following Conjectures, viz. First, That had the Phaenomenon constantly succeeded, we should have suspected the seeming Light to proceed from some Refractions from the Glass darkened within by those white Steams. Secondly, That, since the Air abounds with Parts gross enough to appear in the Sunbeams, and to reflect the Rays of Light, which rise from Bonfires, the Reflection might proceed from some gross Airy Parts within the Receiver. Thirdly, The Whiteness seemed to proceed from the various Surfaces of the airy Parts, reflecting one upon another like Looking-glasses, so as to represent each other contiguous; so Water or Eggs beaten to Froth, lose their Transparency, and appear white: But further having immersed the Neck of our Receiver in Water, and set the Pump on work; the Water being drawn in through a small Hole, had its Parts so broken, that the Receiver appeared full of Milk rather than Water: And if a Piece of Crystal be thrown very hot into cold Water, it will crack, and having so many new Surfaces within appears white. Which Things being considered and weighed, it may not be an improbable Guests, That the aforementioned Phaenomena proceeded from the Parts of the Air displaced as to their Posture and Situation, as, whilst in that Motion, to disturb their former Continuity and Transparency. And this Conjecture may be made probable by observing, That the more Air was included, the more conspicuous was the Whiteness; but more especially by this, viz. That having exhausted the Receiver, and applied a Glass Bubble to the Hole in the Stop-cock, so that there might be a Communication betwixt the Cavity of the Receiver, and it, upon the Exsuction of the Air out of the Receiver, the Air in the Bubble was so disordered, by so sudden a Disilition of its Parts, that it appeared like Milk; but upon a sudden Re-ingress of the Air, became transparent again. But if it should be objected, That the Whiteness in Water turned into Bubbles may proceed from the Interposition of so Heterogeneous a Body as Air; I should answer, That I have in another Place mentioned two volatile Liquors, which being mixed produce a white consistent Body, though both the Ingredients were transparent. But having conveyed some Smoke into our Receiver, and observed upon plying of the Pump, That the Air remaining in the Pump, became opacous; we suspected, that the Reason why the former mentioned Light sometimes appeared and sometimes did not, might proceed from some Parts of Matter swimming in the Air more at one time than another, which was disposed, more to cause such Reflections of the Rays of Light as to afford the forenamed Phaenomenon; which is rendered probable by observing, That the Receiver appeared opaque when the Smoke settled about the Sides of it; and it may further be illustrated by what we mentioned before of our smoking Liquor, where the Corpuscles of it being put into a new Motion became opacous instead of transparent. And if it should be asked, How the Air should abound with such various Parts of Matter? I must answer, That it is not an unusual Observation, That the Air undergoes several and very frequent Changes; for besides several Instances which might be added, the Learned Josephus Acosta observes, That in America, There are Winds which naturally trouble the Water of the Sea, and make it Green and Black; others, clear as Crystal. Besides we observed, That the Pendula as well as Scales suspended in our Receiver, lost a great deal of their Brightness, upon drawing out and letting in the Air. And I once made a Tincture of a certain Metalline Substance, which would become turbid and clear successively, for several times, for which strange Phaenomenon no Reason could be given. EXPERIMENT XXXVIII. Of the freezing of Water and its Expansion. HAVING conveyed a Glass Vessel into our Receiver, in the midst of which was contained a Cylinder filled with Water, and enclosed with Snow and Salt, upon plying of the Pump, the Snow began to melt a little faster than we expected; and the Receiver being pretty well exhausted, the Water in the Cylinder began to freeze; so that, in a little time, the Surface of the Ice was above that of the Water, in which the Snow and Salt was dissolved, and which swum about it. The Superficies of the Water was concave, and being held betwixt the Eye and the Light, appeared full of Bubbles. And it is not a little strange, That there should be so powerful an Expansion in Water froze, as not only to burst Bottles in the Wintertime, but, as I am informed, to separate the solid Parts of Metals; so that Bell-Metal having been exposed to the Wet, and that Wet froze in the Pores of the Metal, it would fly in Pieces; and Cabeus in lib. 4. Meteor. Aristot. relates a no less memorable Account of Vessels made of Stone, which would fly asunder, upon the Expansion of the Moisture lodged in their Pores, and froze there. Where it is not a little strange, That Cold should by freezing Water, cause it to swell, whereas the Effect it hath upon the Air is manifestly to condense it. EXPERIMENT XXXIX. A Phaenomenon taken notice of in the exhausted Receiver. HAving put the End of a Glass Tube into an Oval Glass, so that it almost touched the Bottom, we cemented it to the Neck of that Oval, and then, conveying about six Spoons full of Water into the Egg, we blew it so full of Air, as to force the Water into the Pipe, and to keep it suspended betwixt that Air shut up in the Viol and the external Air; this Weatherglass represented by the Fourteenth Figure, was placed in a small Receiver, at the upper End of the Tube, which was small, being permitted to stand about five Inches above the Cover, the middle of which it penetrated. Upon pumping out the Air, it was to be observed, That the Water in the Pipe manifestly descended; which was an Argument that no Sensible Heat was produced in the Receiver, by the Action of the Pump; since by barely applying my Hand to the outside of the Receiver, that gentle Warmth so far rarified the Air in the Egg, as to enable it to raise the Water in the Tube, much higher than it was depressed, upon the Exsuction of the Air: Tho' we will not thence infer, that the Cavity of the Receiver, was colder after than before the Air was pumped out; since the Pressure of the Air in the Egg, together with the Weight of the Incumbent Atmosphere might, in some measure, cause the sides of the Glass to give way, for want of an equal Pressure of the Air on the Convex, and external Superficies of it; which Guests may seem the more probable, not only because the Springiness of Glass might contribute to the bending of it; but likewise since upon a Re-ingress of Air, the Water was raised up to its former Height again. But to return to our Experiment: From hence it appears, That if there be no Vacuum betwixt the concave sides of the Receiver, and the Superficies of the Bubble, every Substance fine enough to penetrate the Pores of Glass, hath not its Parts in an Agitation, strong enough to produce Heat and Fire. Besides the Former Experiment, having tried what Effect the Exhausted Receiver, would have on Camphire, whose Parts are so fugitive as to fly away when put into Motion, by the Action of Ambient Air, we found that it was not in the least altered. EXPERIMENT XL. Whether Rarified Air will sustain Flying Infects. HAving conveyed a Flesh-Fly, a Butterfly, and a Humming-Bee into our Receiver; the former presently dropped down from the Place she was walking on; and after a few Exsuctions, the Butterfly, which before fluttered up and down, dropped down void of Motion, except a Tremulous one in her Wings. And the Bee in a little time, was wholly deprived of Motion: But whether the Falling of them depended on the Thinness of the Medium, which was unapt for them to swim in or not, will appear from the following Experiment. EXPERIMENT XLI. Concerning Respiration. HAving conveyed a Lark into our Receiver, and closed it up; upon plying the Pump, the Bird presently began to droop, and when the Receiver was further exhausted, being first taken with violent Convulsions, and Tossing up and down the Cavity of the Vessel, it died with it's Back contiguous to the Receiver; it's Head directed down towards the Stop-cock, and its Neck awry: And tho' at ten Minute's Distance, after this Bird was closed up, the Air was again let in at the Stop-cock, yet did it not recover again. And the like succeeded upon Enclosing a Hedge-Sparrow, except that the Air being let in again, at the end of seven Minutes, it recovered by degrees; but when it seemed able to fly away, the Receiver being again exhausted, it died in five Minutes Time. Having enclosed a Mouse in our Receiver, it continued to leap up for some Time after the Air began to be exhausted; but in a little Time after that, it appeared sick and faint, and very giddy, and at the last fell down dead; yet upon a Re-ingress of Air, presently recovered; but the Air being again pumped out, in about ten Minutes, it died moderately convulsive. And it was not only observable in this, but all the other Experiments of this Nature, that I tried, that the Included Animals died convulsive. And to make it appear, that in the Forementioned Trials, the Animals died for want of Air, and not by being choked up with Fuliginous Recrements; I enclosed another Mouse in our Receiver, which, the Air not being drawn out, lived 3 Quarters of an Hour; but upon pumping out the Air, in ten Minutes, died convulsive. And another being left in all Night, was alive the next Morning, and had eat Cheese, which was, for Tryal's sake put in with him, A Digression containing some Doubts touching Respiration. HAving made these Experiments relating to Respiration, it may perhaps be expected that I should say something concerning the Usefulness of Air in Respiration. In doing of which, it is not requisite that I should take Notice of the Structure of those Parts, since they have been sufficiently described already. Nor shall I any further engage in that Controversy, Whether the Motion of the Lungs depends on the Motion of the Thorax, or not, or how the Lungs are distended by the Air, any further than it may be Illustrated by our Engin. As for the First Part of the Controversy, it seems to be determined in favour of the Affirmative, by what the Learned Dr. Highmore, and Bartholinus have observed; the former having taken Notice, That the Lungs subside, if the Intercostal Muscles be so wounded, as to lay the Thorax open; and the latter having observed the same upon a Division of the Diaphragm: But what it is that conveys the Air into the Lungs, is yet undetermined; since some think it to proceed from the Dilatation of the Thorax impelling the Air contiguous, and what it contiguous to that, successively into the Lungs: But this Supposition is fairly answered, since it is possible to breathe out of a Glass, where the External Air pressed on by the Thorax, can only press on the outside of the Bottle. But a more easy Solution may be taken from our Engine, since it appears, That if the Lungs be dilated by the Thorax, the Spring of the Air is sufficient to force it in, there being less Resistance made by the Rarified Air in the Lungs, than that in the open Atmosphere. And tho' there are some Observations, which testify, that when the Diaphragm hath been considerably wounded, without damaging Respiration, yet since the Lungs are void of Musculous Parts to dilate themselves, we are rather inclined to believe that they are dilated by the Expasion of the Thorax, and filled by the Gravity, and Pressure of the Atmosphere. But to proceed to the Use of Air in Respiration, besides the Usefulness of it in Modulating Sounds, and the Conveying of Odours, it is beyond Doubt, That it is in a great Measure necessary to the Preservation of Life, tho' as to the Manner of its Contributing to the Continuance of Life, several disagree; since it is by some thought only to keep the Blood from growing too hot in the Ventricles of the Heart. But that this is not all that the Air, in Respiration, performs, is evident, since not only Old People, but several Creatures, have no need of Cooling their Blood and Humours being cold enough without it, yet they cannot live without Respiration. Others hold that the Air being conveyed into the Left Ventricle of the Heart, contributes to the Generation of Spirits; but since there appears no such Passages, as are fit for its Conveyance, we shall not here recite what other Arguments might be alleged against it. But others, as Moebius and Gassendus, are of Opinion, that it chief serves to Ventilate and Carry off the Excrement of the Blood; for as a Candle may be extinguished by its own Smoke; so the Heat of the Blood might be prejudiced, were not its Fuliginous Recrement carried off, by mixing with the Air upon Inspiration. Which is Congruous enough, to what hath been observed by several Travellers; viz, That there is a certain Consistence requisite in the Air, to carry off such Fumes; for it is observed, That if the Air drawn in, be too much impregnated with Vapours, as in some Cellars, when Damps arise in Mines, it becomes so unfit to Brach, as to stifle those that do not avoid the Latter, or use some Method to rarify it, as by holding a Chaffing-dish of Coals near their Faces, to disperse and scatter those Fumes. And to confirm these Observations, I shall add, That having closed a Bird in our Receiver, I observed, that the Air being thickened by frequent Respirations, it began in a little time to pant and gape, and at the last grew so sick, as to throw foul Matter off its Stomach; and in 3 Quarters of an Hour to be ready to die: And that the Receiver should be so filled with Steams, needs not seem a Wonder, to any one that considers, what Sanctorious hath observed, viz. That the greatest Part of our Aliment is carried off, by Insensible Transpiration. And as these Instances show, how unfit an Air too gross, is for Respiration; so that an Air too thin is likewise prejudicial, appears from the Experiments already tried in our Receiver; so that it is not Improbable that if a Man were removed to the Top of our Atmosphere, he would die for want of Breath. In favour of which Conjecture, I shall add, That the Learned Josephus Acosta, tells us, that going up a high Mountain in Peru, called Pariacaca, which was so high above the Alps, as to make them appear only as high Towers, he and his Companion were taken with excessive Vomiting, together with Blood, which lasted till he came to a Region more convenient for Respiration; and he likewise says, to our present Purpose, That the Element of the Air is so subtle and delicate there, that it is too fine for a Man to breathe in; the Action of Respiration, requiring a grosser and more temperate Air. But tho' from hence it appears, that the Air contributes to Respiration, in carrying off the Recrements of the Blood; yet it is scarce probable, that those Recrements should so soon kill an Animal, as to cause Birds enclosed in our Receiver, to die in a few Minutes, for want of being carried off. And it would not be harder to account for such Effects, should we allow with Paracelsus, That Air contributed to the Geneneration of a Vital Spirit; since the Interruption of its Generation, for so small a time could scarce be fatal. Yet I shall add on this occasion, That I have been told, that Cornelius Drebellus, made a Boat for the Learned King James, which would swim under Water, in which, to make the Air included fit for Respiration, he was wont to open a Vessel which contained a Liquor, which added such a Vital Spirit to the Air, as purged it of the grosser Exhalations, and condensed them. Wherefore I am the more favourably inclined to think that the Air may conduce to the Preserurtion of Vital Spirits; and that it contributes to the Preservation of Life, as Air to Flame; for having conveyed rectfyed Spirit of Wine into our Receiver, we found, that it would not continue long, no more than the Vital Flame of an Animal, if the Air was exhausted. But not to insist upon these things, we shall add, That having dissected a Bitch, and taking out one of the Whelps, tho' we opened his Abdomen, and Thorax, and divided the Diaphragm; yet having once began to breathe, his Heart continued to beat above six Hours; whereas three more, which were involved in the Secundines, in the mean time, were all dead; tho' they were neither wounded, nor had ever breathed. How far this may serve to illustrate the Problem proposed by Dr. Harvey, viz. Why a Foetus may live longer before it hath breathed, if involved in the Secundines, than if, when it hath once respired, Respiration be stopped, we leave others to judge. Whether Fishes breathe or not, under Water, especially those that want Lungs, I cannot now determine; but that Air is necessary to the Preservation of their Lives, seems to be evinced, by observing, that if Fishes be enclosed in a Bottle, which is close stopped from the Air; or if they be kept from the Air by the Freezing of Water, they presently die. And indeed, considering how many Particles of Air are interspersed in the Pores of Water, it may not be altogether improbable, that part of it is separated, as it passes through their Gills, or some other way: And I am the rather inclined to believe it, because having put a large Eel into our Receiver, upon exhausting the Air, she turned up her Belly, and lay as dead, till the Receiver being unstopped, and the Fish taken out into the open Air, satisfied us of her Recovery, by very brisk and vivid Motions. But what is not a little to be admired, having put a Grey Snail into our Receiver, we perceived not the least Alteration, when the Air was drawn out; but whence these Phaenomena proceeded, we shall not now stay to determine. Nor are we now at leisure to examine any further, whether the Paradox which some hold, be true, viz. That the Child respires in the Womb; only we shall say that it is not altogether Fabulous, That the Foetus hath sometimes been heard to cry in the Womb; and Chickens have been observed to pip in the Eggshell, before it was broke; which may be Arguments of an obscure Respiration, except it can be made to appear, That such Sounds may arise from Halituous Vapours in the Larynx; and that they may, will not be a little favoured, by observing what audible Sounds arise from the Halituous Vapours of an Aeolipile forced upon the Blade of a Knife, held in various Postures. But to proceed, the Necessity of Breathing, tho' those that are not well are accustomed to want it, may appear, from the small time, that such Men are able to stay under Water; but may further be illustrated by the following Experiments: For having conveyed a Humming-Bee, a Flesh-Fly, and a Palmer-Worm, into our Receiver, upon the Exsuction of the Air in a Minute's Time, they all seemed dead; but presently recovered by the Re-ingress of Air; yet when the Air was again drawn out, they appeared dead, which is a strong Argument to induce us to believe, that the Bodies of Animals are but so many Curiously-contrived Engines, except those of Men, whose Wheels are set on going, by the Influence of External Agents; for even those Flies, which presently die in our Receiver, will crawl about, even when their Heads are cut off. And it is not unworthy our Observation, That Infects which want Lungs, are no less sensibly affected upon the Exsuction of Air, than some that have them, which may be Grounds for a Suspicion, that the Particles of the Air enter in at their Pores, and that it keeps them alive by a Universal Perspiration. But to put an End to this Digression: Tho' the Experiments have given me cause to suspect, that the Depuration of the Blood, is the chief Use of Respiration; yet since I believe it hath some other Uses, which are not yet explained, I shall conclude with that Saying of St. Austin's; Mallem quidem eorum quae à me quaesivisti, habere Scientiam quam Ignorantiam: sed quia id nondum potui, magis eligo Cautam Ignorantiam confiteri, quam falsam Scientiam profiteri. EXPERIEMINT XLII. The different Operations of Corrosives in, and without our Receiver. HAving filled the third part of a Long-neck Viol., with ten Sprigs of Coral, and as much Spirit of Vinegar, as swum about an Inch over them, we placed it in our Receiver; and tho' at the first there appeared but very few Bubbles, yet upon a few Exsuctions of the Air, they risen so plentifully, as to make the Menstruum appear white, the whole continuing to boil and ferment, as in a Seething-pot, as much Froth standing upon the Liquor, as answered the Depth of it, in the Viol: Yet upon letting in the Air, the Froth presently disappeared, and the Liquor became transparent again. And these Phaenomena successively followed each other, no less than five times, as the Air was drawn out, or let in again; and the Ebullition in those Trials, upon the drawing out of the Air, was so great sometimes, as to run over the Top of the Glass; and that those numerous Bubbles might not be suspected to arise from the Spirit itself, we cleared it of those, before the Coral was put in, but the same Phaenomena, still succeeded: nor was there any considerable Difference, when the Trial was made with Powder of Coral, except that the Liquor was obscured by several Parts of it carried up along with the Bubbles. But one thing in the Foregoing Experiments, was remarkable, That tho' the Ebullition was so violent, yet the Viol immediately taken out of the Receiver, did not affect our Hands with the least sensible Heat. EXPERIMENT XLIII. Of the spontaneous Ebullition of warm Liquors. HAving closed in our Receive a Viol of four Ounces filled with hot Water, which had been freed from Air by boiling, we pumped out the Air, and observed, That upon the fourth Exsuction, it began to boil, as if it had been over a hot Fire, so that part of it ran over, and continued boiling in our Receiver. And what was more remarkable, was, that as often as the Air was let out of the Receiver into the Pump, the Ebullition was again renewed, the Fiery and Agitated Parts of the Liquor, upon a Removal of the Air's Pressure, having more Liberty to expand themselves. And that the Phaenomenon was promoted by the Removal of that Pressure, we may guests, because the Ebullition was only in the Top of the Liquor; and that it was renewed upon a Removal of that Pressure. But especially, because Salad-oil, whose Parts adhere, by Reason of their Clamminess, would not ferment; yet Oil of Turpentine, or Wine would, whose Parts are not so tenacious; the former rising five times its Height, and near four Parts of the latter running over into the Receiver. From all which Experiments it appears, that the Air may have a considerable Influence on a greater Number of Phaenomena than Men usually think of, especially where the tumultuous Agitation of the Parts of a Body are concerned; so that were a hot Body conveyed above the Atmosphere, the Effects of it would be different from what they are here below, and the Parts of it would have more Power to dissipate themselves. Having thus far, My Dear Lord, given you a faithful Historical Account of the Productions of your Lordship's Commands, if they may invite you or your Friends at Paris to a further Prosecution of what Discoveries may be made by that Engine, I hope they may afford your Lordship as much Pleasure as they did me in endeavouring to express myself, Your Lordship's Most Obedient Servant, etc. CHAP. XIV. The Doctrine of the Spring and Weight of the Air defended against Franciscus Linus. THIS Chapter containing the Honourable Author's Vindication of his own Hypothesis, concerning the Weight and Spring of the Air: It will not be requisite here to lay down, all the trivial Objections of Franciscus Linus; which are easily answered, by any one that hath but read and considered the Author's Hypothesis, and will at the first sight appear to be ill-grounded or invalid Arguments, or rather false Criticisms: But, it being more consistent with the designed Epitome, I shall only take notice of such, as may serve to illustrate the Hypothesis already laid down, and think it unnecessary to fill an Epitome with, what our judicious Author did not repute as Arguments against his Doctrine: And especially, because the Learned World, by their General Consent have agreed upon what the Honourable Author hath taught: Wherefore I shall lay down only those Objections which may seem considerable, and annex their Solutions. The first Argument of Franciscus Linus Answered. The first Argument alleged by Franciscus Linus, is, That, did the Suspension of the Mercury in the Cylinder, depend on the Aequilibrium of the Weight of the Atmosphere; when a Cylinder is filled full and inverted, upon an Inversion of the Tube, and a Subtraction of the lower Finger, the Mercury would not subside, were its descent not promoted by the Dilatation of the Air above the Mercury; for if it were, that Expansive Force would raise the Finger upon the upper Orifice of the Cylinder. To which is answered, That the included Air may depress the Mercury by its Expansion downwards, without raising the Finger; for the Weight of the whole Cylindrical Pillar of the Atmosphere, which presses upon the top of the Finger, being too strong to be overpowered by the weak Expansion of the Air in the Pipe, it must consequently press downwards, where the Weight of the Mercury is ready to join with it to overbalance the Pressure of the Air, which before buoyed it up: And that the Weight of the Cylinder of Mercury disposes it to spend its expansive Force downwards, appears from a Cylinder of Water suspended instead of Mercury; for the Weight of that being not able to resist the Pressure of the Atmosphere downwards, equally as the Mercury; the Air in the Top of the Cylinder does not press it down near so far: And tho' the Objector says, that if Water instead of Air be above the Mercury, it will not subside; the Reason of that is only, because the Water wants a Springiness to expand itself: And as for the Reason why the Pulp of the Finger seems to be drawn down into the Tube, that only happens, by Reason of the Weight of the Incumbent Atmosphere, the Rarified Air within, not being able to make an equal Resistance to prevent the Finger from being pressed into the Pipe: And though the Objector further urges, that he cannot conceive how the Air can be so expanded without possessing a greater Space, we have sufficiently cleared that, by comparing the Expansion of the Air's Spring to a piece of Wool squeezed together, which when it is no longer Compressed, dilates it self by Virtue of its springy Parts. A snd Objection. The second Objection is, That if Mercury be suspended in a long Pipe, about 40 Inches long, when the Tube is inverted, and the Finger is taken from the lower Orifice, it falls down till it comes to its usual Station; and the Pulp of the Finger is equally depressed into the Tube; which evinces, that the Mercury is suspended by a Funiculus, which draws down the Pulpy Part of the Finger. But, what Answer is to be given to this Objection, Answered. appears from what hath been said to the former; for the Mercury subsiding, till it came to an Aequilibrium with the Atmosphere; the Air above it being very much Rarified, and unable to buoy up against the Finger; the Depression of the Pulp of it must proceed from the Weight of the incumbent Atmosphere, tho' the swelling of the Pulp in the Pipe might perhaps partly proceed from an Expansion of the Humours within the Substance of it, the Weight of the Atmosphere being prevented from squeezing upon it by the Equivalent Weight of the Mercury. A third. Objection answered. Another Objection is, That if a Tube twenty Inches long, be immersed in Quicksilver, and when it is full, the upper Orifice of it be stopped with one's Finger, as well as the lower, upon taking away the lower Finger, the Pulp of the upper will be drawn down, tho' the Weight of the Atmosphere is said to be able to buoy up a Cylinder much longer; So that this is a plain Demonstration of the Suspension of the Mercury by a Funiculus, and that it is not buoyed up by the Pressure of the Atmosphere according to the Elaterists. But tho' this Objection may seem to represent some Difficulty, yet it will easily be answered, by thus explaining the Phaenomenon, viz. Tho' when the Tube is stopped at both Ends, the Finger upon the Top of the Tube be equally pres'sd upon on both sides; yet, upon a Removal of the Finger below, tho' the Pressure of the Air upon the Finger continued to be the same, yet the Pressure of the Mercury is by two Thirds less, against the Pulp of the Finger, its Gravity pressing upon the subjacent Air; for notwithstanding the Air is able to buoy up a greater Quantity, yet that in Part takes off the full Pressure of it, so as to make the Pressure upwards, disproportionable to that which tends downwards: And tho' the Objector urges, that the Mercury is equally suspended upon a Removal of the Finger, as before; I answer, that the Finger presses it up much more strongly, to prevent any of it getting out; whereas the Pressure of the Air only depends on the Weight of it, which cannot be intended or weakened, as that of the Finger may, which is capable of raising a much greater Weight. Another Objection answered. Another Objection alleged by the Author is, that were the Mercury buoyed up by the Weight of the Atmosphere, it would be as easy to suck up Mercury in a Pipe as Water, nothing more being requisite but to draw away the Air. But this may easily be taken off by considering, that the Dilatation of the Lungs depending upon an Ingress of Air upon the Motion of the Diaphragm and Intercostal Muscles, and that Air being pressed in by the Gravity of the Air and its Spring, it will follow, that that Gravity or Spring being more powerfully resisted by the Cylinder of Mercury than Water, the Lungs cannot so powerfully dilate; nor can the Mercury be raised with equal ease, because, that Air in the Lungs, together with the Weight of the Mercury, brings the External Force of the Atmosphere nearer to an Aequilibrium. Besides, the External Air pressing upon the Thorax, and keeping them from dilating themselves, the Air contained in them, pressing against the Superficies of the Mercury in the Tube, is a further Cause, why it rises not so high; which Explanation is confirmed by observing, that as the Lungs are more violently dilated, the Mercury rises higher in the Tube; and it will be further Probable, by considering, how much greater a Pressure may be made upon so large a Superficies as that of the Thorax, than can be resisted by the Rarified Air in the Lungs. And as for the Funiculus, which our Author supposes to raise the Mercury, by contracting itself; it would not be a little strange, that it should raise such a Weight as a Cylinder of Mercury, without tearing off the thin Membranes of the Lungs to which such a Funiculus must, at one end be joined. To these Objections the Author adds an Inference, that if the Spring of the Air be of no Force, in loco aperto, no more can be effected by it in loco Clauso; but the Place which the Objector takes to be in loco Clauso, appearing to be only in a Room; It is answered, that whereas the former Objectoins appear to be invalid, the Inference must be so too; because there being a Communication betwixt the Air in a Room and the External, by some Holes or Crannies, or otherwise, the included Air will be able to do as much by its Spring, within as without. CHAP. XV. The Funicular Hypothesis Examined. THE Hypothesis laid down by our Adversary, and which is now to be examined, Arguments in favour of the Funicular Hypothesis examined. is, That what we ascribe to the Spring and Weight of the Air is done by a sort of Funiculus, consisting of a thin Substance powerfully expanded, which being betwixt two Bodies, endeavours to contract itself, and to bring those Bodies together, ne detur Vacuum. The first Argument alleged, is, That the Finger would not be so drawn down by the Descent of the Mercury, were there not a Funiculus; and that were there not a thin Substance there extended, there would be a Vacuum, As to the first Part of the Argument, it hath already been answered in the foregoing Chapter. And tho' he alleged the Necessity of such a Funiculus from Nature's Abhorrency of a Vacuum; the first Argument he offers, being deduced from the Suction of the Pulp of the Finger upon the Descent of the Mercury, It is likewise already Answered by what hath gone before in Explaining that Phaenomenon. But another Argument he alleges against a Vacuity is, the Diaphaneity of that Part of the Tube; for were there a Vacuum, he says it would be like a black Pillar, neither capable of affording any thing visible, nor of permitting visible Objects to appear through it: But the Invalidity of this Argument will appear from the Doctrine of the Epicureans and Atomists, who Teach, that Light is made up of such subtle Emanations, as are capable of penetrating Glass itself, and tho' the Cavity of the Cylinder may seem full of Light; yet no doubt, but were the Parts of luciferous Matter condensed into a Lump, they would not fill half the Cavity; since the Smoke which filled up the Cavity of our Receiver, so as to make it appear Opacous, was but capable of filling a small part of it, when condensed. Besides, should the Torrecellian Experiment be made in the Dark, a Vacuist might argue, that the Matter, which upon an Access of Light was visible, was not in the Receiver before, but proceeded only from the Rays of Light darting through the Glass: And tho' Light should not be caused by a Trajection of such luciferous Beams, but from an Impulse of luciferous Bodies; yet would it not thence follow, that the Tube was full; since from our seventeenth Experiment it appeared, that when the Receiver was in a great measure exhausted, there remained a sufficient Quantity of Matter behind, to communicate a tremulous Motion to the External Air: And tho' it should be allowed, that the Cavity of the Tube were filled with the Cartesian Materia subtilis; yet, since they allow that capable of passing in and out upon the Access of a grosser Body, it would not be any more to his Purpose, in maintaining his Funicular Hypothesis or opposing Ours, because such a Body as so easily passes in and out, will be as ready to give way to the Motion of a more gross Body, and consequently to the rising or subsiding of the Mercury. Another Argument alleged in Favour of the Funicular Hypothesis, is, that when the Mercury is subsided to its wont Station, it gravitates no farther. But it being already shown, why it does not, viz. because it is counterbalanced by an equal Weight or Pressure made by the Atmosphere, what hath gone before hath been a sufficient Answer. And if it should be asked, why, when the Finger is pressed upon, by a Cylinder of the Atmosphere, and at the same time by a Cylinder of the Mercury on the other fide, it feels no sensible Pain; it may be answered, that the Pressure being equal on each side, the Sense of Pressure is the less perceptible; which is confirmed by what divers observe at a considerable depth under Water, viz. that they are not sensible of it. And if it should be further asked, why upon the Descent of the Mercury, it, at the first, falls something below its wont Station, and presently rises up again, it may be answered, that that proceeds from an Impetus acquired by its Descent, which at the first partly overpowers the Spring of the Air below it; but that Impetus being quashed, the Spring and Weight of the Air presently weighs it up again to its usual Station; and having been put into a little more than ordinary Compression, raises it something higher; so that the Impetus upon a second Descent brings on a successive Elevation, till at the last the Impetus on each side gradually is lost, and discontinues that vibrating Motion; and this may not only be illustrated by the successive Vibrations of a Pair of Scales put in Motion by depressing one and elevating the other; but was farther confirmed by Mercury in a Glass Tube, made use of in our 36th Experiment, for having put a Quantity of Mercury into it, and by inclining of it permitted it to run into one Leg, I stopped the Orifice of the other with my Finger, upon which, the Tube being erected, the Air contained in the Syphon, which was stopped at the Top, depressed the Mercury in that Tube; but as soon as it was unstopped, the vibrating Motions of the Mercury began and continued to rise and fall successively for some time. CHAP. XVI. A Continuation of Objections against the Funicular Hypothesis. BESIDES the forementioned Objections, there are several others which perplex the Funicular Hypothesis: As first, How the superficial Parts of two solid Marbles, which adhere together, when exactly polished, can be drawn out into a Funiculus; a Difficulty which does not at all perplex our Doctrine. Besides, were the Funicular Hypothesis allowed, it might be questioned, How it comes to pass, that Liquors whose Parts are not equally liable to be extended into such Funiculus' should exactly subside till Aequiponderant to 29 ½ Inches of Mercury, and no further; an Objection which our Doctrine admits not of, since not only from Windguns, but our former Experiments, it appears too manifestly to doubt of the Air's Spring and Gravity. Nor is the Author's strange Method of producing his Funiculus less exceptionable; for he says, When the Mercury touches the Top of the Tube, upon its Descent, it leaves its Superficies to stick to the Top of it, which is extended by the Weight of the Mercury, till it leaves another Superficies joining to that; where it may be objected, That neither Sense perceives any such Thing, nor can it be made probable by Reason; it being impossible to conceive, How the Superficies of a Body can be so extended as to become a Body itself: And should it be allowed, that the Funiculus might be turned into so subtle a Body, it would be altogether inconceivable how it should be so firm and strong, as to suspend the Weight of a Cylinder of Mercury; and that it should have such an admirable Property as to extend without being made thinner, contrary to the Nature of all Ropes. Besides, the Method he takes to illustrate his Generation of the Funiculus, by comparing it to the Flame of a Candle, does not enforce the Belief of it any more; for not to urge, That the Parts of a Candle, are by Agitation, and a powerful Motion amongst each other, kept at such a distance, as to leave several and a Multitude of Vacuities betwixt their Parts; if the Rarefaction of the Mercury in the Funiculus be like that, when it is raised in the Form of a Vapour, it would be too slight to suspend a Tube of Mercury. And it might be further demanded, How the Funiculus came by such Hooks, as to take hold of every Body contiguous to them, so firmly, as to be able to break strong Glasses, by drawing their sides inwards; and how Fluids should be so suspended, as to appear one entire Piece, contrary to what their Fluidity disposes them to do. Nor is it less strange, That our Objector should allow this subtle Body a Spring which he denies to be in Air; since Nature's Abhorrency of a Vacuum cannot be the Cause of it, in as much as a Vacuum would not ensue, according to his Doctrine, tho' it were not contracted. Moreover, it would not be a little hard to conceive, were such a Funiculus allowed of, how the Surfaces of Marbles extended, could contract into Marbles again; and how in the Cylinder of Mercury, the Funiculus is so easily relaxed, upon an Admission of Air into it, since, it filling up all the Space above the Mercury before, it cannot easily be conceived how it should be dispossessed of that Space, without being thrust into another. Again, I should be glad to know, if the Cavity of our Receiver, upon an Exsuction of Air, were filled with such stretched Strings, it would be possible for a Pendulum to move in it without breaking them; but our Author's Funiculus being made up of Strings, endued with peculiar Qualities, we shall decline making any more Objections, since these Peculiarities may be sufficient to distinguish it from Truth. CHAP. XVII. The Aristotelian Rarefaction Examined. The Aristotelian Notion of Rarefaction rejected. BESIDES the former Objections which render the Funicular Doctrine unintelligible, there are yet others, upon the Account of the Doctrine of Rarefaction employed in the explicating of it. For the Doctrine of Rarefaction made use of by our Author, supposing a Body not only to fill up a larger Space, when rarified, but likewise so to fill it, as not to leave the least Vacuities betwixt its Parts; it will be very hard to conceive, How a Hundred Parts of Matter, which are circumscribed by so many Spaces of the same Extension with themselves, should be capable of filling up more Space adaequately than they are circumscribed by, without the Addition of other Matter; and it seems strange, That without the immediate Act of Omnipotence, Matter should be so extended as without any Addition to alter its Dimensions. And tho' our Author takes two Ways to explicate his Notion, either upon a Supposition of the Parts of Matter being indivisible or divisible in infinitum; yet, since he explicates it neither of those ways so clearly, as to make it intelligible, I must confess, I cannot acquiesce in them; nor are the Difficulties at all made less by asserting, That Matter may be virtually so extended as to possess more Space than is circumscribed by it; since a virtual Extension is as unintelligible as Extension without the Term virtually joined with it; for since he seems to allow the Parts of Matter to be indivisible, it rather prejudices the Doctrine of Rarefaction as taught by Aristotle, than explains it; since it is inconsistent to think, That a Body, whose Parts are circumscribed by a certain Space, should fill a larger Space, without being divided and removed out of the former. Nor does it at all explain or render the Aristotelian Doctrine of Rarefaction, to say, That Matter may, by Omnipotence, be so ordered, as to possess adaequately double the Space it did before; since in Natural Philosophy it is not disputed what GOD can do, but what he hath done. But besides the Difficulties in our Author's Doctrine of Rarefaction, there are no less in the Condensation which his Funiculus supposes; for since he allows of no Vacuities in it, it is impossible the Parts of it should be brought nearer than to touch one another, without a Penetration of Dimensions, which is wholly disallowed of, and by no means to be admitted in Nature; for were that allowed, two or three Thousand Bodies might be contained in a Space, which every one of them by itself would fill; which is altogether unintelligible. CHAP. XVIII. A Consideration concerning some Trials of the Torrecellian and other Experiments ' at the Tops and Feet of a Hill. The Height of Mercury suspended at the Top of a Hill. FOr a further Proof against Our Adversaries Doctrine, and for a Confirmation of ours, I shall add the following Experiments. And First: The Famous Pecquet mentions an Experiment, made by Monsieur Pascal, at the Foot of a Mountain 3000 Foot high; where when he ascended, 150 Fathom, the Mercury in the Cylinder was not buoyed up so high, as at the Bottom, by two Inches and a Quarter; and at the Top of the Hill, it wanted 3 Inches of that Station, which it was suspended at, at the Foot of the Hill; which is a strong Argument against our Adversary; the Difference plainly appearing to depend on the different Length of the Atmospherical Cylinder, which was abler to weigh up the Mercury at the Bottom, than the Top of the Hill. And Gassendus, Tom. 1. P. 211. relates, that the like was observed 5 times on the Hills at Auvergne. And a very Noted Virtuoso, Mr. J. Ball, as well as that Ingenious Gentleman Mr. Townley, have observed the like in England. And it was by the last named, likewise observed, that the Mercury included in the Top of the Cylinder, was not able to depress the Mercury, near so much at the Bottom, as at the Top of the Hill. But to discover the weight of the Air, and its Spring, without going up to the Top of such high Mountains, we made use of the following Wether Glass, suspending Water in the Pipe, instead of Mercury. The Instrument was a Glass with a broad Foot, and a narrow Neck (A B), and a slender Pipe of Glass (C D), which was open at both Ends; and so placed, that the lower End was not far from the Bottom (A B), and was so closely cemented at the Neck (A), See Fig. the First, Plate the Second. as to prevent the Internal Air (I I) from communicating with External (K K), unless it were through the Pipe (C D). And having conveiged Water (H H) into the Glass (AB), which was pretty large, and having blown so much Air into the Bottle, as to raise the Water in the Tube above the Vessel, upon the Leads of Westminster Abby. When the Air was thought to be equally Cold and Condensed within the Bottle, as without; we marked the Station of the Water (F), and letting it down by a String to the Ground, the Water subsided an Inch, where its Station (E), being marked, and the Vessel drawn up again, the Water was raised to the Mark (F) again. Which Experiment being again tried, had the like success. And afterwards the Top of the Tube being broke, we let it down within the Church, the Surface of the Water in the Pipe being at (G) an Inch above the Water in the Glass; where I observed, that the Air so depressed it, when it came to the Bottom, as to force the Water out of the Pipe into the Glass, several Bubbles breaking through into the Capacity of the Glass, and this Glass being drawn up to the Top of the Church again, the Water was manifestly raised in the Tube again; from whence it appears, that the Atmosphere gravitates more; Caeteris paribus, the nearer the Surface of the Earth; for the Experiment being repeated, we found that as the Height, at which it was tried, varied; so the Elevation or Depression did. Another Particular which may be a further Confirmation of our Hypothesis, is, That which is mentioned by Monsieur Paschal, viz. That a Football being weakly blown, and carried to the Top of a Hill, swelled more and more, as it was carried higher; and as gradually grew lank, when it was carried down the Hill again: From whence it appears, That as the Atmosphere is longer or shorter, it makes a greater Gravitation and Pressure upon the Bladder. To this I shall add an Experiment, sent to Dr. Croon, by a Learned Professor of Gresham College, See Fig. the Sec. Plate the Second. which is the following: Having Observed that in the Weatherglass (A B), represented by the Second Figure, which was about two Foot long; the Water was suspended in the Pipe, about thirteen Inches above the Superficies of the External Water, at the Bottom of Hallifax Hill; but being carried to the Top of the Hill, it subsided an Inch and a Quarter, to the Point (D). The Internal Air (A C), which was taken in at the Bottom, dilating itself at the Top further by (C D). In which Experiment, the Descent being much more considerable than what it ought to be in such a small Ascent, by the bare Pressure of the Atmosphere diminished, the Reason appears to be, the Expansion of that Air included in the Top of the Weatherglass; as well as the Shortening of the Atmospherical Cylinder. CHAP. XIX. Experiments concerning the Measure of the Force of the Spring of Air, compressed and dilated. TO make it evident, That the Spring of the Air is able to do much more, than we have attributed to it, upon the Account of its Spring and Weight, we tried the following Experiments. The Air's Condensation measured. Having poured Mercury into a Glass-Tube, which consisted of a Long Leg, and a Short One, which were so bend as to lie Parallel almost to each other; we pasted Papers upon each, which were divided by Marks into Inches, and each of those Inches into eight Parts; and upon pouring Mercury into the Longer Tube, we observed, That the Air contained in the Shorter, which was Hermetically sealed at the Top, by twenty nine Inches of Mercury, was condensed into half the Space it possessed before; from whence it appears, that if it were able in so compressed a State, by Virtue of its Spring, to resist a Cylinder of Mercury of 29 Inches, besides the Atmospherical Cylinder incumbent upon that, it follows, that its Compression in the open Air, being but half as much, it must have but half that weight from the Atmosphere, that lies upon it, in that Compressed State. But to be more exact, See Fig. 4. Plate 2. we took a Tube represented by the Fourth Figure, pasting upon the Shorter Leg a Paper, divided into twelve Inches, and each of those into Quarters; and another upon the Longer Leg, which made up several Feet, which were likewise divided into Inches, and those subdivided again into Quarters. The Tube being thus Marked, the Lower End was placed in a Wooden Box, that the Mercury might run into it, if the Pipe chanced to break: And one being assigned to pour in Mercury at the Top of the Tube, another was placed to observe, when the Mercury in the small Tube, risen up to each of the Divisions, ; and to take notice likewise, how high it stood in the Long Tube, at the same time, where the several Observations were set down, and are contained in the following Table. A Table of the Condensation of the Air. A A B C D E 48 12 00 Added to 29 ⅛, makes 29 2/16 29 2/16 46 11 ½ 01 7/16 30 9/16 30 6/16 44 11 02 13/16 31 15/16 31 12/16 42 10 ½ 04 6/16 33 8/16 33 1/7 40 10 06 3/16 35 5/16 35— 38 9 ½ 07 14/16 37— 36 15/19 36 9 10 2/16 39 3/16 38 ⅞ 34 8 ½ 12 8/16 41 10/16 41 2/17 32 8 15 1/16 44 3/16 43 11/16 30 7 ½ 17 15/16 47 1/16 46 ⅗ 28 7 21 3/16 50 5/16 50— 26 6 ½ 25 3/16 54 5/16 53 10/13 24 6 29 11/16 58 13/16 58 2/8 22 5 ½ 34 15/16 64 1/16 63 6/11 21 5 ¼ 37 15/16 67 1/16 66 4/7 20 5 41 9/16 70 11/16 70— 19 4 ¾ 45— 74 2/16 73 11/19 18 4 ½ 48 12/16 77 14/16 77 ⅔ 17 4 ¼ 53 11/16 82 12/16 82 4/17 16 4 58 2/16 87 14/16 87 ⅜ 15 3 ¾ 63 15/16 93 1/16 93 1/● 14 3 ½ 71 5/16 100 7/16 99 6/7 13 3 ¼ 78 11/16 107 13/16 107 7/13 12 3 88 7/16 117 4/16 116 4/8 A, A, The Number of Equal Spaces in the Shorter Leg, which contained the same Parcel of Air differently Expanded. B, The Height of the Mercury in the Long Tube, by whose weight the Air in the Short one, was compressed. C, The Height of the Mercury, which counterpoised the weight of the Incumbent Atmospere. D, The Aggregate of the Columns B and C, showing what Pressure was sustained by the Included Air. E, What that Pressure should be, allowing the Pressures, and Expansions, to be Reciprocal Porportions. But in Trying this Experiment, whoever pours in the Mercury, he must do it by degrees, and according to the Directions of the other, that takes notice of the Ascent of the Mercury below; for if it be poured in without Caution, it may rise up above the Marks placed on the Outsides, before due Observations can be made. Having, by the weight of so vast a Cylinder of Mercury, compressed the Air into a Quarter of the Space it possessed before, we observed, tho' it could not be sensibly condensed further by Cold, yet the Flame of a Candle brought near it, gave us reason to think, that a greater degree of Heat would have expanded it; but fearing the Cracking of the Tube, we durst not try it. From the Experiment it appears, That as the Air is more or less compressed, so it is able to counterpoise a Heavier or Lighter Cylinder of Mercury. And that the Mercury was born up by the Spring of that condensed Air, appeared by sucking up the Air out of the Tube, when the Mercury was 100 Inches high in the Pipe; for the Pressure of the incumbent Pillar of the Atmosphere, being by that means taken off, the Mercury was raised in the Long Tube, by the Expansion of the Air in the Short Leg: And not by any Funiculus, since the Objector confesses, that cannot raise more than a Cylinder of 30 Inches. The Air's Rarefaction considered. But, together with what hath been said, it may not a little illustrate our Doctrine of the Spring of the Air to observe, how much its Spring is weakened, accordingly as it is differently Expanded, and Rarified. A Table of the Air's Rarefaction. A B C D E 1 00 0/9 Substracted from 29 ¾, leaves 29 ¾ 29 ¾ 1 ½ 10 ⅝ 19 ⅛ 19 ⅚ 2 15 ⅜ 14 ⅜ 14 ⅞ 3 20 2/8 9 4/8 9 15/12 4 22 ⅝ 7 ⅛ 7 7/16 5 24 ⅛ 5 ⅝ 5 19/20 6 24 ⅞ 4 ⅞ 4 23/24 7 25 4/8 4 2/8 4 ¼ 8 26 0/0 3 0/8 3 23/32 9 26 ⅜ 3 3/0 3 11/36 10 26 6/3 3 0/0 2 39/40 12 27 ⅛ 2 ⅝ 2 23/48 14 27 4/8 2 2/8 2 ⅛ 16 27 ●/8 2 0/0 1 55/64 18 27 ⅞ 1 ⅞ 1 47/72 20 28— 1 6/8 1 9/80 24 28 ⅛ 1 4/8 1 22/96 28 28 ⅜ 1 ⅜ 1 1/16 32 28 4/8 1 2/8 0 110/128 A, The Number of Equal Spaces at the Top of the Tube, which the same Parcel of Air was contained in. B, The Height of the Mercury, which together with the Included Air, counterpoised the Pressure of the Atmosphere. C, The Pressure of the Atmosphere. D, The Aggregate of B to C, representing the Pressure counterpoised by the Included Air. E, What that Pressure should be, according to the Hypothesis. In which Experiment it is to be Noted, First, That we made use of a Glass-Tube, about 6 Foot long, sealed at one End. Secondly, We had in Readiness a Glass-Pipe, about the Diameter of a Swan's Quill, which was marked with a Paper stuck upon it, divided into Inches, and half Quarters; which being immersed in the other Cylinder of Mercury, and open at both Ends, that the Mercury might rise in it, it helped to fill the other up. And about an Inch of its standing above the Mercury, the Orifice was sealed up; so that an Inch of Air was contained in the Tube, which, by lifting up the Tube, was gradually expanded to several Inches: It being noted, in the mean time, how much the Mercury in the small Tube, was, by the Expanded Air, in several Stations, permitted to rise above the Surface of the Mercury in the other Tube: By which Method, the former Observations being made, we inverted the Large Tube, and found by trying the Torrecellian Experiment, That that Day the Air sustained the Mercury at 29 ¾ Inches; where it was observed, That in making the foregoing Observations, the Difference betwixt the Account which answers our Hypothesis and the other, probably proceeded from a new Access of Air, to that included Inch; and indeed, by immerging the Tube, when the Observations were made, we found, that it had gained about half an Eighth; which we judged might arise from some Bubbles lodged in the Pores of the Mercury. From which Experiment it appeared, that the Inch of Air expanded to double its Dimensions, was able with a Cylinder of Mercury abvot 15 Inches, to counterpoise the Pressure of the Atmosphere, which would raise the Mercury eight and twenty Inches, when the Spring of that Air was lost, by a further Expansion: So that the Atmosphere here below, must consequently be as much compressed, as if twenty eight Inches of Mercury gravitated upon it. CHAP. XX. Objections against Particular Phaenomena answered. The reason why Air condensed by Cold, does not raise Mercury equally, as when condensed by Pressure. WHAT our Author says in the Vindication of Particular Experiments, being only a Repetition of what he had said before against the Objector's Funicular Hypothesis, there is no need now to make a Repetition; since the Funicular Hypothesis, being already confuted, it consequently follows, that the Explications are Erroneous. I shall therefore only take Notice of what hath not yet been delivered, or not so fully explained. And First, The Reason why the Air condensed in Winter, by Cold, does not buoy up the Mercury equally, as when the Air is condensed in a Vessel, is because that condensed Air adds no greater a Weight to it; but as a pound of Feathers, it is as heavy when compressed, as before that Compressure; but when expanded Air is condensed in a Vessel, it acts more Powerfully by Virtue of its Spring. Mr. Boyl hath taken a great deal of Pains in his Explications, to show several Absurdities in the Objections; but those being neither Useful, nor Instructive, especially considering the Objector's Hypothesis is wholly laid aside, and our Author's Received, it will be needless to take notice of what will be of no Use in Explicating the Phaenomena before delivered. CHAP. XXI. An Explication of Rarefaction. IT being objected by the Author of a Book, De Corporum Inseparabilitate, that the Spring of the Air cannot be made out, whether we allow a Vacuum, or a Plenum. Waving the Forms which he lays his Objections down in, and a particular Answer to his Ways of Arguing, I shall take the following Method, to explain the Air's Spring. For supposing the Particles of the Air to consist of Matter, extended into thin Laminae, and those wound and folded up, like the Spring of a Watch; and that these Parts of Matter so wound up, are in a Continual Circular Motion, it will follow, that the Laminae in this Motion will endeavour to extend themselves, and to recede from the Axis or Centre of their Motion, till hindered by the Opposition of each other, or some adjacent Bodies: and this Expansive Endeavour will be proportionably increased, as the Circular Motion of those Particles is quickened. And these Springy Corpuscles thus shaped, and thus Mechanically moved, are sufficient to account for all that we ascribe to the Spring of the Air. For supposing the Diameter of those Parts of Matter next the Surface of the Earth, compressed by the whole Weight of the Incumbent Atmosphere, to be 1/1000000000000 of an Inch, See Plate the Second. and to be represented by the Third Figure A B C D; it will Naturally follow, that Part of the Incumbent Weight of the Atmosphere, being taken off, they will expand themselves so as to be 10/1000000000000 of an Inch in Diameter, as represented by E F G H. so that these Zones whirling round, will take up a space 1000 times bigger than before. And as from hence the Rarefaction of the Air is naturally accounted for; so the swelling of a carps Bladder, upon taking off the Pressure of the Atmosphere, is explained by the same Reason. And as the spontaneous Rarefaction of the Air is hence naturally explained, so it's Forced Rarefaction by Heat, is; for if the Particles of Heat penetrating the Interstices of these Airy Particles be in a violent rapid Motion, by increasing the Motion of the former Particles, they increase the Motion of the latter, and consequently strengthen their expansive Virtue; And if these Rarified Parts of Matter, by expanding themselves, leave larger Interstices betwixt their Laminae, they must consequently be more pervious to the Rays of Light. So that granting this innate Motion in the Parts of Matter, and such a Configuration as I have mentioned, it naturally follows, that all the Phaenomena belonging to Rarefaction and Condensation, may easily be explained by it. Rarefaction according to the Doctrine of the Plenists. Nor will it be impossible to explain the Rarefaction and Condensation, admitting of a Plenum, if we suppose with Cartesius, That the Air consists of Parts which are long, slender and flexible; for supposing with him, that these are whirled round by the Rapid Motion of the Globuli Coelestes, those that lie next the Surface of the Earth, must needs be compressed and hindered from that expansive Motion, more than those that have less Weight upon them; and consequently, when that Compression is taken off, the expansive Force being increased by it, they will consequently be expanded more Powfully; and by whirling round, acquire longer Vortices: And for the like Reason the Air contained in the carps Bladder, will extend itself when the Pressure of the External Atmosphere is taken off; and consequently, when the External Pressure is again admitted, those springy Parts being again compressed are less able to maintain their new Vortices, but being wound up together again become more condensed, that Pressure resisting the Force of their Spring. And as for the Reason why Water flows into the Receiver again in the Magdeburg Experiment, so impetuously; it hence evidently appears to proceed, from the Weakness of the Spring of the included Air, not being able to resist the more violent Pressure of the External; and for the same Reason likewise, the carps Bladder upon a reingress of that Air, is presently compressed into its former Inconspicuousness. Elasticity explained by the Cartesian Hypothesis. Nor will it be a less Piece of difficulty to explain the Aptness of Explosion in Gunpowder, by the Cartesian Hypothesis; for the Parts of that Combustible Matter of which it is made being shattered and broke into Pieces, consequently become more apt to be whirled about by the Materia Subtilis, and justling against each other, take up 1000 times as much space as before; and these Parts being thus agitated whatever Gunpowder they fall upon, they presently shatter its Parts so as to put it in a Capacity to be agitated by the Materia Subtilis: and consequently, the Globuli secundi Elementi, being expelled out of the Place which contained the Gunpowder, and the Parts of it being impetuously moved in that, they not only burst the Vessel they are contained in, but drive every thing out of its Place which stands in their way, and is not able to resist them. CHAP. XXII. An Explication of the Rota Aristotelica. NOT to mention all those Absurdities which Mr. boil hath showed in the Author's Explanation of the Rota Aristotelica, See Plate the second Fig. 5. I shall pass on to lay down what Explanation Mr. Boil himself gives of it; for Mr. boil conceiving no such Difficulties in it, as our Author would represent, says, that it is so far from containing any Obscurities in it, that it is plain and easy. For if the Wheel A B C D. be moved in a direct Motion from A I C. to K L M. each of the Points A E I G C. will either on a Plain, or in the Medium it passes through, form so many parallel Lines to I L. But if instead of that direct Progressive Motion, it have a Circulation, each Point in one Revolution, whilst moved from G to L. will form a Cyclorid. Besides, each Point of the Circle acquires various Degrees of Celerity in its Progression by this complex Motion, according to its various Position to a Point, which is always to be found in some part of the Line, drawn from the Centre of the circular Motion Perpendicular to the Progressive; for as the Circumference to the Radius, so is the Line of the Progressive Motion to the distance of the Point from the Centre; because the Line of Progression is equal to the Circle, described on that distance as Radius; and therefore, each Point of the smaller Circle, when it touches the Perpendicular, will in respect of its Progressive Motion stand still: This Point therefore, will be the Centre of the complex Motion. Our Author's Explication of the Rota Aristotelica. But since it may sufficiently explain the Rota Aristotelica, if we only consider those Points which pass across the Perpendicular, we shall suppose in our Example that A is the Centre or Point; and then the Circumference A B C D will be equal to I L or A K by our Hypothesis. And since the Point I hath only one motion, viz. that of Lation, the Point C which hath two Motions, must have double the Velocity of I, and the Point F having the same Degree of Lation with I, and put half the Distance of C from the Centre I, it must have one Degree of Motion and a half. And further, the Point E having the same Progressive Motion with I, and being moved backwards with half the Velocity, loses half the Progressive Motion forwards. And the Point A being by its Progression moved forwards, with an equal Velocity with I, and by its Rotation (the Circle A B C D being equal to the Line I L) being carried back with equal Celerity, must necessarily stand still as to the Progressive Motion. Now from hence it appearing, that the Point A, (being at Rest, by reason of its two opposite Motions) only touch a Point of the Line A K, without being in the least moved upon it, and that the Point E, (moving forwards as fast again as it is carried backwards by its Rotation, and consequently moved half as fast as the Point I) not only touches the Line E K, but is moved upon it with a progressive Motion, half as quick as that of I, it will consequently follow, that each Point in E must make a small Line, which is a Part of the whole E C; so that the Contact of the former, and the Contact and the Progression of the latter, being performed by an infinite Succession of Points, in an infinite Succession of Instants, the Difficulties represented by our Author's Explaining it, are taken off, all that he says coming to no more, than that in such a determinate Moment or minute's Space of time, such a determirate minute's Corpuscle, will successively pass over such a determinate Space or Length. CHAP. XXIII. An Abstract of what is further contained relating to the Weight and Spring of the Air in the Examen of Mr. Hobbs his Dialogus Physicus. IN this Chapter I shall not take notice of what Absurdities the Author hath showed Mr. Hobbs guilty of, but shall only extract what may tend to a further Illustration of the Doctrine of the Air's Weight and Spring. And first, from what hath been before delivered concerning the Weight and Spring of the Air, it appears, that the Reason why the Water in a watering Pot, is prevented from descending through the Holes of the Bottom, by stopping the upper Orifice, is no other than the Pressure of the Atmosphere; which making a stronger Resistance than a Cylinder of Water of such a Length is able to resist, it must consequently be suspended in the watering Pot: and that this is the true Reason, appears from what hath been delivered in the nineteenth Experiment; where it was made evident, that if the Pressure of the Air was weakened by extracting the Air out of the Receiver, as soon as the Water in the Tube was able to outbalance the Spring of the included Air, it began to subside. CHAP XXIV. The Weight and Spring of the Air asserted. THE Author having proved the Weight of the Air, by weighing it in an exhausted Receiver in a Lamb's Bladder, and a Glass Bubble, and likewise in an AEolipile: And the Air's gravity being further confirmed, by weighing the Receiver before and after it had been exhausted in the Magdeburg Experiments: All that Mr. Hobbs objects, relating to the Bladder weighed in the Receiver, only intimates, that the Air being blown into the Bladder, the Weight proceeds from Atoms which swim in that Air, or the Haltius which pass into the Cavity of the Bladder along with the Air: But since this denies not the Weight of the Air, but rather questions the Cause; we think it sufficient to account for what we aimed at, to prove, that Air does gravitate, tho' the Cause of Gravitations be not known. The Spring of the Air proved. As to the Spring of the Air, waving what trivial Objections Mr. Hobbs makes, I shall add the following Experiments to evince it. The first, is, That if a Cylinder of Mercury be suspended at the usual Height, in the Torrecellian Experiment, by stopping the upper Orifice of the Tube, and lifting the lower End above the Basis it rested on before; we may observe, that the Finger can discern no Gravitation of the Mercury in the Tube; but if it be inverted, and the External Air let in, the Mercury which before did not gravitate upon the Finger, will be so depressed by the Spring of that Air, as to cause it to weigh considerably upon it; and if the lower Orifice be unstopped in the restagnant Mercury, the included Air will depress that in the Tube, below its former Stations: And if the Experiment be made in a Tube not so long, and both Ends be stopped with one's Finger, upon the removing of the uppermost, the lower will perceive the Weight of the Incumbent Pillar of the Atmosphere, which before depressed the Pulp of the Finger into the Cylindrical Cavity of the Tube; so that this Experiment proves both the Spring and Gravity of the Air. The other Experiment is the Fourth in the Epistle, where it was evident, that a Bladder suspended in the Receiver, subsided or swelled as the Air was let in, or drawn out: And tho' Mr. Hobbs teaches, that the swelling of the Bladder is effected by the Air, per vim incussus, which getting into the Bladder, presses against the Internal Superficies of it in their circular Motions; yet, since from several Experiments it appears, that Bladders are impervious to Air, to deny that the Ingress of it, is a sufficient Answer to his Explanation: But further, were the Bladder so pervious to Air, it might as readily get out of the Bladder, as in, without breaking it. And whereas Mr. Hobbs endeavours to explicate all the Phaenomena afforded by our Engine and Windguns, by the Motion of the Airy Parts, which Motion they acquire by the Force of the Engine; yet, that the Air hath parallel Effects where it acquires no such Motion, appears from the Experiments formerly mentioned made in the open Air, at the Top and Bottom of Hills; the Mercury being not near suspended so high at the Top, as at the Bottom of those Hills. And tho' he endeavours to Explain the difference, by supposing the Motion of the Air brisker at the Bottom than the Top of the Hill; yet, since it can only keep the Mercury from subsiding, by virtue of its Pressure, that Pressure must either proceed from its Spring or Weight; and since it is highly improbable, that the Pressure of so few Parts of the Air, as are contiguous to the Mercury, should be able to keep it from subsiding, it must do it by virtue of the whole Atmosphere which is equiponderant to it. But to evince the Spring and Pressure of the Air further, I shall add, that a Thermoscope being carried to the Top of a Hill, the Air contained in it not finding so strong a Pressure from the Water, which there receives a less Impression from the Atmosphere, visibly expands itself by virtue of its Spring. CHAP. XXV. Mr. Hobb's Principal Explications of the Phaenomena of the Engine Examined BEfore Mr. Hobbs sets about an Explication of the Phaenomena exhibited by our Engine, he lays down an Hypothesis, which he endeavours to explain them by; supposing that a great many earthy Particles are interspersed in the Air, which have a congenite circular Motion of their own; and that there is a greater Quantity of them nearer, than further from the Earth: But besides that it may be questioned, how such Particles can move in so exact an Order, without knocking against, and disturbing each others Motion: It is as unintelligible how Matter should have its Motion congenite: But to leave Mr. Hobbs to dispute these things with other Adversaries, I shall proceed to his Explications. The exhausted Receiver void of Air. And first, to prove that there is no Vacuum in our Receiver, he says, that the Air being removed by the Pressure of the Sucker outward, it gets into the Receiver again betwixt the Convex and Concave Surfaces of the Sucker and the Cylinder, which if. true, it would follow, that there was a Vacuum for some time, viz. till the Air had time to get into the Receiver again. But that the Air is in a great Measure drawn out, and that the Receiver is, in respect of Air, empty, not only appears by those Bubbles of Water which pass through the Water, when the Receiver is encompassed with it; but it further appears, by weighing the Receiver when exhausted, which is considerably lighter than before. As also, by observing, that if the Receiver be ill shaped, so as not to be able to resist the Pressure of the outward Air, it breaks inward upon the Action of the Pump. But a further Argument is, that the Receiver being exhausted, and the Cocks turned when the Receiver is encompassed with Water, several Gallons will be impelled into it, which could not be without a Penetration of Dimensions, except the Receiver was empty. And even in the Common Experiment its evident, that the Air, upon turning of the Stop-Cock, rushes in with a considerable Noise. But if Mr. Hobbs should say, that the Purer Air only flows into the Receiver; I shall demand, how it is possible for that to flow in, when the Receiver is exhausted in Water; where we might expect, that it should as well raise Bubbles in its Passage through it, as that such Bubbles rise in the Water in the exhausted Receiver. And tho' Mr. Hobbs affirms, That this Air getting into the Receiver moves up and down violently I know not how; to prove that it does not I shall intimate, That were it so, the Smoke as well as the Bladder contained in the Receiver in the forementioned Experiments, would be disturbed by that Motion; since upon the Admission of the Air into the Receiver, it appears, That it puts them both into a very violent Agitation. And, That in the Torrecellian Experiment, the Tube above the Mercury is void of Air, may be evinced, by reciprocally inverting the Tube; for by that Means, the Mercury will move backwards with a much greater degree of Swiftness and Force, than if Air be let into that Part of the Cylinder which is not filled with Mercury. And indeed, were it not allowed, That the Air is drawn out of the Receiver, for any thing that Mr. Hobbs hath offered, the Reason of the Ascent or Descent of the Mercury, as the external Air is let in or drawn out, would be difficulty understood, if not altogether unexplained, without admitting the Weight and Spring of the Air. The next Phaenomenon Mr. Hobbs offers to explain is, why the Sucker rises up when the Receiver is exhausted, tho' a hundred Pound Weight be suspended at it; the Reason of which he attributes to the swift and violent Repercussion of the Air, which was thrust out, which finding not room enough in the World, must conseuqently press the Sucker before it into the Space which contained it before; but if the Air be so swiftly repelled, I cannot understand, why it should not resist the Egress of Air, or raise the Sucker when a greater Weight is hung at it. But further, that the return of this Air does not depend on the swift Repercussion of the external Air is hence manifest; since if the Sucker be held down till the Air about it seems to be settled, and as calm as before; it will nevertheless rise when the superfluous Weight is taken away. And as for an Internal Conatus of the Included Air, were such allowed, as Mr. Hobbs contends for, it would rather hinder than promote the Rising of the Sucker; for were that Included Air forced out so violently, as he supposes, and were it strong enough to cause a violent Repercussion in the Air, the Internal Force counterpoizing the External, the Rising of the Sucker would not thereby in the least be promoted: But since from our Experiments it appears, That the Receiver is, for the greatest Part, void of Air, and that such an Impetus would be of no Force, in causing the Phaenomenon he endeavours to explain by it, it is more Natural to belive, that the External Pressure of the Atmosphere raised it. CHAP. XXVI. Several scattered Explications, and Passages in his Dialogue, considered. WHEREAS we have in the XXXXVth Experimenti, mentioned an Experiment, wherein the Water Risen up into a long slender Tube, which was placed in a Perpendicular Line; the Water in the Tube, being above the Surface of the Water, without the Tube; Mr. Hobbs endeavours to explain this, by the Impulse of the Particles of Matter, swiftly agitated in the Air; but since the same Agitation of Parts within the Tube, might also depress that to an equal Surface, with the External, the Account he gives of it, is the less satisfactory. The Reason which he assigns for the Difficulty in drawing up the Stopple, when the Receiver is exhausted, is, a Violent Conatus, proceeding from the Motion of the Particles within; but were the Impetus so great, as to cause so great a Repercussion, as Mr. Hobbs before supposed able to repel the Sucker, it should rather raise the Stopple; and if that Motion contributed to the fastening of it, it would continue upon a Readmission of the Air; since the Air in the Cavity runs about, and is in Motion for a good while: Nor could the Plenitude he supposes, cause the Phaenomenon, because he supposes the World to be equally, and at all times full. But that the close Connexion of the Stopple to the Socket, depended on the Pressure of the External Air, appeared by closing the Hole in the Cover with Cement, instead of that Stopple; for when the Air was drawn out of the Receiver, the External Air was drawn out of the Receiver, the External Air would press so violently upon it, as to make the upper Superficies Concave, and sometimes to force it down into the Receiver with a Noise, and great Violence. He further assigns the Boiling of Water in our Receiver, to the Motion of the Air included; but since I have made it appear, That there is no such Motion, our Explanation is the more probable; since the Parts of the Liquor being agitated by Heat, will be apt to to expand more powerfully upon a Removal of that Pressure. And tho' he says the Parts of the Water could not be moved, except à Movente contiguo, A Contiguous Body in Motion; yet since he allows, that the Motion of his Earthy Parts, which swim in the Air is innate, and consequently depends not on any Contiguous Body, I shall leave that to answer what he here delivers; and shall only intimate, That the Parts of the Water being agitated, when put into the Receiver, is enough to account for the Phaenomenon, when the Pressure of the Air is taken off. Why Animals die in the Exhausted Receiver. The sudden Death of Animals, which I ascribe doubtingly, tho' not without Probability, to the Exsuction of the Air in the Receiver, he attributes to the Circular Motion of the included Air, and its Tenacity; but since I have already made it appear, that there is no such Motion, that is a Sufficient Answer. And as for the Air, being thicker in the Exhausted Receiver, than before, the contrary appears in the Magdeburg Experiment; where the Exhausted Receiver weighed much less than before; but from the Breaking of Bubbles outwards it further appears, that it is not a thicker, but a lighter and more yielding Body: And tho' Mr. Hobbs from his supposition of the Air's Thickness, endeavours to Account for the sudden Extinction of Flame in our Receiver; yet thinking it a Matter of Difficulty to explain, the true Cause of the Extinction of Flame, it may suffice, that I have made it appear, that the Air is not thick as he supposes. CHAP. XXVII: Several other Passages in Mr. Hobbs' Dialogue, examined. IN this Chapter Mr. Hobbs objects against what our Author delivers, concerning the Cause of the Coliesion of two Marbles; but all that is contained in what he here offers, being obviated by what hath been delivered under the Title of Fluidity, and Firmness; For a further Confirmation of the Doctrine there delivered, I shall add the following Experiments: And, The Pressure of the Air upon Bodies contained in it, proved. First, If an Aeolipile freed from Air, be, whilst hot, stopped with Wax, upon a Perforation of that Wax, the Air will be pressed in to the Cool Aeolipile, whether the Orifice be held down, or Horizontally; which shows, that the Air on each side may press upon the Lower Superficies of the Marble, as well as the Subjacent Pillar of Air, and that the Air is not impelled against it only in a Pyramidal Figure, as he would urge, viz. because Lines drawn from the Circumference and Borders of the Stones, to the Centre of the Earth, must form Pyramids. To which it might be added, That Part of the Air being drawn out of a large Glass, and a Book clapped upon the Orifice, the Pressure of the Subjacent Atmosphere, kept it suspended there. And the Author of the Magdeburg Experiment says, That two Plates of Copper, whose Diameter was about half an Ell, stuck so close to each other, that six Men could not pull them asund. * See Fig. 6. Plate second And it appears from an Experiment made in a Glass Viol., anon to be described, that if the Tube be so immersed, that it's Lower Orifice just touch the Water, the obliqne Pressure of the Atmosphere, will raise the Water in the Tube, a considerable Height, as the Air is sucked out of the Tube. Mr. Hobbs objects against the Author's Explications of the Rising of: Water in Glass Fountains; and says, That it cannot be accounted for by the Expansion of the Air, since the Parts of the Air expanded, take up no more room after they are expanded, than before; but since he means so as adequately to fill more Space; and we only mean such an Expansion, as is before explained, by instancing compressed Wool; it appears, that in our Sense it will take up more Space, so as to keep the gross Parts of Water from getting betwixt them. There are other Objections mentioned in this Chapter, as well as some other Particulars, relating to the Royal Society; but since the Author finds no weight in them against any thing he hath taught; I shall only further take Notice of what Mr. Hobbs and Gassendus teach, concerning the Rise of Water in Syphons; viz. That it is performed by Suction. But not now to mention what hath elsewhere been delivered to prove the contrary, I shall only add the following Experiment: Having taken a Glass Vessel, which was large enough to contain about a Pound of Water, I caused a Glass Pipe to be fixed in the Neck of it; so that the Air within was kept from having any Intercourse with that without, the Lower End reaching almost to the Bottom of the Vessel: The Pipe being thus fixed, we conveyed Water into the Bottle, till it risen something above the Bottom of the Pipe, and then having inclined the Bottle to give a due Intercourse betwixt the Internal and External Air, I sucked the Air out of the Tube, till the Water risen into my Mouth, and till the Spring of the Included Air, was able no longer to lift up the Water; which would not have done, been were the Common Notion of Suction allowed, viz. That it is effected by the Pressure of the Air, thrust away by the dilated Chest of him that sucks, and thereby drawing the Water into the Pipe at which he sucks. But besides the Preceding use made of this Experiment, I poured out the Water, till the lower End of the Pipe was but just immersed in it; and upon Suction, it risen almost to the Top of the Pipe; but the Spring of the Air being too much weakened to raise it higher, several Bubbles of Air broke through the Water; but as soon as I left off sucking, the Pressure of the External Air so compressed the Rarified Air within, as to bring it to its wont Station, several Particles breaking into the Bottle through the Water, till that Internal Air was equally pressed with the External. CHAP. XXVIII. What Mr. Hobbs teaches concerning Fluidity and Firmness, examined. Motion the Chief Qualification in order to Fluidity. THE First Particular examined in this Chapter, is a Mistake of Mr. Hobbs, concerning the Author's Opinion of Fluidity; the Objector making the Author's Notion of Fluidity to consist in the Size of the Parts of Liquid Bodies; whereas our Author assigns Motion, as the Chief and Principal Qualification; since a Coagulum of pure Spirits of Urine and Wine, may by bare Digestion, be turned into a Permanent Liquor; and Quicksilver, tho' fluid, may be turned into a Permanent Powder, by stopping the Motion of its Parts. And tho' Mr. Hobbs further asserts, That Fluid Bodies consist of Parts Divisible into Fluids, as Quantity into Quantity; yet, since I have made it appear, That Fluidity depends on the Shape, Size, Texture, and Motion; and Firmness, on a Rest amongst the Parts of Solids; and likewise, that Fluids' are not divisible into Fluid Parts, as Quantity into Quantity, it is needless to repeat what is there delivered. As for the Explication of Fluidity and Firmness, which Mr. Hobbs Substitutes, it teaches, That the Parts of Fluids' may move whilst the whole is in Motion, and that Solids may have their Parts in Motion, tho' the whole lies still: As also he says, That the Parts of a Fluid may be rendered less fluid, by being compressed; but since he hath asserted these things, and not proved them; and since the Hypothesis he goes upon, is sufficiently invalidated before, the Author thinks these require no Particular Answer: And tho' he further makes an Objection against the Size of the Parts of Matter contributing to Fluidity and Firmness; yet since our Author makes Motion or Rest the Chief and Principal Requisites, what hath been delivered in the History of Fluidity and Firmness, may suffice for an Answer: For that there is Motion in the Parts of Fluids', appears, if a Lump of Salt be put into Water, the Parts of which will be presently dissolved, and carried up to the Top of the Liquor, which could not be without Motion; and that Rest contributes to Solidity, is evident, since Water froze, becomes Ice; and on the contrary, that, as well as Metals, by having their Parts put into a violent Motion by Heat, become Fluid. CHAP. XXIX. An Explanation of the Engine made Use of in the following Experiments. See Plate the Third and Fourth. THE Structure of our Engine being such, as not to admit of an Alphabetical Explanation, so as to make it intelligible, to those that are unacquainted with Mechanical Structures; and it being easily enough understood by those, especially that are acquainted by our First Engine, we thought it sufficient in our Plate, to represent the Engine just ready to be set on Work; and in the Fourth the Parts, which it is made up of. Only there are two things, which may deserve to be explained: First the Sucker being always covered with Water; and the Perforation (p q), which goes through it in a Perpendicular Line, and together with the Stick (r s), supplies the Place of a Valve, being to be stopped at the Bottom of the Cylinder (n oh), when filled with Water, it was necessary the Stick (rp) should be of a considerable Length. Secondly, The Pipe (A B) lies in a Gutter, made purposely in the Board (c d e f), which Board is laid over with Cement, and a piece of Iron laid upon that, to keep it from warping: In which Iron-plate is fixed a Lip, which rises up about the End of the Pipe (B), which is bend up, to prevent the Water which comes from the Receiver from being Spilt; and notwithstanding the Stop-cock (G H I K), might be inserted into the Cylinder (L M N O), at (I) with Soder; yet it is much more convenient to have the Branch (I) made like a Screw; so that being screwed into the Barrel, it may more easily be mended, when any thing is amiss; Whether it be that the Air gets in betwixt the Plate and the Wood, or the Cement be drawn into the Pipe, where the inverted End is united to the Receiver; and lest the inward Orifice of the Pipe should be stopped with any thing, contained in the Receiver drawn to it, there is fixed at some Distance from it a Tin Plate, so contrived as to give free Passage to the Air. The Wooden Part represented in the Plate, and which contains the Cylinder, is always so full of Water as able to overtop the Cylinder, and to make the Sucker soft and plump, by which means it is more exactly fitted to the Cylindrical Cavity. And as for the Iron Plate , it hath this Conveniency, that it excludes the Air, better than if the Receiver had a Stop-cock, in most Experiments, tho' in some it is less servirceable. But most of the following Experiments may be tried in our First Engine, if the following Alterations be made. And First, If a square Board, and a suitable Iron Plate, such as is made use of in this Engine, be fastened opposite to the Iron Rack, to the Upper Part of the great Cylinder, and a Glass Tube, like that just now described, be fixed to the Lower Branch of the Stop-cock, with a Cement, made with near an equal Proportion of Wax and Turpentine, in Winter, and three Parts of Wax to two of Turpentine in Summer; for the Ingress of Air being thus prevented, upon drawing down the Sucker, the Air, by Virtue of its own Spring, will force itself out of the Receiver. CHAP. XXX. A Continuation of New Experiments concerning the Spring and Weight of the Air and their Effects, by way of Letter to the Right Honourable the Lord Clifford and Dungarvan. My Dear Lord, HAving already given your Lordship an Account of the Design and Scope of our Mechanical Experiments, without any further Preface, being encouraged by your Acceptance of my last, I shall proceed to a Continuation. EXPERIMENT I. Concerning the Raising of Mercury a great Height in an open Tube, by the Spring of a small Quantity of included Air. IN order to make an Estimate of the Force of the Air's Spring, in its several Degrees of Expansion; We filled the fourth part of a Viol with Quicksilver, the Neck of which was none of the largest, in which we fixed a Glass Tube with hard Wax, the lower End reaching almost to the Bottom of the Quicksilver, and the upper almost a Yard above the Viol, which being conveyed into a Receiver (See Plate 5. Fif. 1.) which was pretty Tall, See Plate 5. Fig. 1. upon an Exsuction of the Air in the Receiver, that in the Viol expanding itself, raised the Mercury 27 Inches in the Tube; yet when the Air was again admitted into the Receiver, it subsided so far as to be almost; if not quite equal with the Surface of the Mercury in the Viol: And this Experiment was tried before the Famous Savilian Geometer Dr. Wallis, tho' it does not constantly succeed alike, it sometimes rising higher than at others. In which Experiment the following Observations were to be made. First, That so much Air being blown into the Viol, to try whether it was staunch, as was able to raise the Mercury three Inches in the Pipe, upon the Exsuction of the External Air in the Receiver, the Mercury risen 30 Inches above that in the Viol. Secondly, When the Mercury is taken out of the Receiver, it does not suddenly subside as low as before its Ascent, the Air being a little more Expanded by the Heat of the Cement when melted with an Iron. Thirdly, Whilst the Air included in the Viol retains any considerable Springiness, after each Exsuction the Mercury will be raised by the Force of its Expansion, a considerable Height above what that Air is able to suspend it at, and makes several Vibrations before it settles. Fourthly, Upon the first Exsuction the Mercury rises near ⅔ of the whole Weight that the Expansion of the included Air is able to raise it, and continues every subsequent Exsuction to rise less and less as the weight of the suspended Mercury increases, and the Spring of the Internal Air grows weaker, and as the Mercury rises less every Exsuction than it did before, so are the Vibrations less considerable. Lastly, Having observed the Weight of the Air in a good Barometer, when it was but light, the Mercury was raised to 29 and ⅜ tho' soon after the Trial it was but 29 Inches high. To make an Estimate of the Quantity of Air which raised the Mercury to the usual height, we counterpoised the Viol, and then filling it full of Water, we found it to weigh about 5 Ounces 2 Drachms, and about 20 Grains; but so much being poured off, that the remaining Water only filled the Space which the Mercury was before contained in, it weighed 1 Ounce 2 Drachms 14 Grains, so that the Air which by its Expansion elevated the Mercury, filled the Space of no more than 4 Ounces and a few Grains: The Diameter of the Pipe employed in this Experiment was no more than the ⅛ of an Inch. An Argument against a Fuga vacui. But besides the Spring of the Air, from this Experiment we may learn, what is to be thought of what some Learned Men teach concerning the Suspension of Quicksilver by a Funiculus, and, it's rising to avoid a Vacuum; for were the first true, it might be demanded, why that Funiculus raises it not above 27 Inches; and as for the latter it's objected, that the Mercury being unable adequately to fill up more Space by rising, than if it risen not, the Reason must be invalid. EXPERIMENT II. A good Quantity of Air raised the Mercury in an open Tube, no higher than the Weight of the Atmosphere does in a Baroscope. HAving put a sufficient Quantity of Mercury into a large Bottle, capable of containing about ssij, we immersed the one End of a long slender Tube, below the Surface of the Mercury; and having closed the Neck of the Viol with Cement, it was conveyed into a Receiver different from the former in nothing but Size; where we observed, that the Quantity of Air being greater in this Viol, than that made use of in the former Experiment, it was capable of expanding further, and of raising the Mercury to about 29 Inches and about ⅞ out of which half an Inch being deducted, for the height it was elevated to by Air injected to try the Stanchness of the Bottle, the Spring of the Air included in the Bottle, raised it to 29 Inches and about ⅜; The Weight of the Air in a Baroscope at the same time, elevating the Mercury 29 Inches and ½, which was ⅛ higher than the elevated Mercury in the Receiver. But having continued to ply the Pump still longer, we learned, that the Spring of the included Air was incapable of raising it higher, than the Weight of the Atmosphere did in the Baroscope. This Experiment was several times repeated with the like Success, but once, the Pump being plied more than usually, the Air contained in a Green Glass expanded so violently, that tho' it could not raise the Mercury higher, it broke the Glass with such violence, that the Piece which flew off cracked the Receiver. EXPERIMENT III. The Spring of the included Air, will elevate Mercury almost to an equal Height in Tubes of a different Boar. IN order to try, whether the same Quantity of Air would by its Expansion raise the Mercury to the same Height in a narrow, as in a Cylinder of a larger Diameter, we repeated the former Trial with a Pipe of the same Diameter, but much longer; in which the Spring of the Air raised the Mercury to 28 Inches and ⅛, the Mercury in the Borometer, being 29 Inches and ¼ high at the same time. So that the Air was able by its Spring, to raise the Quicksilver within an Inch as high in a large Tube, as in a smaller: And when the Spring of that Air was no further able to expand itself, the Parts of it being put into Motion by Heat, the Spring of it was so much increased, as to raise the Mercury ⅝ of an Inch higher. EXPERIMENT IU. A new Hydraulo-Pneumatical Fountain made by the Spring of uncompressed Air. HAVING put a Quantity of Water into a Bottle, and immersed the End of a Glass Tube a little below the Surface of it, which was about 3 Foot long, the Interstices betwixt the Neck of the Bottle and the Pipe were filled with Cement (see Plate 6. Fig. 2.) and the whole was conveyed into a Receiver. See Plat. 6 Fig. 2. And because the Pipe was too long to be contained in the Receiver, another made of White Glass was Cemented upon the former, to the middle of whose Cavity, the upper End of the Pipe extended, so that the Motions of the rising Water had more Space to move in, when the Pump was set on work; where it was observable, that upon the first Exsuction the Pressure of the external Air being taken off, that contained in the Bottle, expanded itself so powerfully, as to raise the Water in the Tube with such Force, that it flew violently against the Top of the Receiver; but as the Air in the Bottle was leisurely expanded, and came nearer to an Aequilibrium with that in the Receiver, the Spring of that in the Bottle, being less powerful, the Water in the Tube gradually ceased in its Ascent, unless the Pressure of the external Air was taken off by a fresh Exsuction In which Experiment, the following Particulars were to be noted; First, that as the upper Orifice of the Tube was narrower, the Water would rise slower, and the Experiment would be longer continued. Secondly, If a Pipe be Cemented upon the Top of the Tube, and branched out into several small ones, with Pin-holes in the Ends of them, the Water will fly out, as out of Artificial Fountains in Grottoes. Thirdly, If the Bottle to whose Neck the Tube was Cemented, was larger, the Water would rise so much the longer; and the Experiment might be reiterated by first letting in the Air again, and then exhausting the Receiver by pumping it out afresh. From the Phaenomena exhibited by this Expement, it appears, that the Spring of the Air was able to raise the Water in the Tube to a much greater Height than the Pipe we made use of. Secondly, From hence it appears, that Water contained betwixt two Parcels of Air, may be put into Motion by its Spring, without the Concurrence of adventitious Heat. Thirdly, we observed, That when the Air was in a great Measure exhausted, the upper Receiver being taken off, the external Air pressed the Water quite down to the Bottom of the Tube, and several Bubbles getting through the Water, joined themselves with the Air in the Bottle: But what was more strange was, that when the Receiver had been taken off a considerable time, several Bubbles of Air continued to make their way through the Water, as if the Spring of the Included Air, being before expanded, could not be brought again to its former State of Compression; but like a Balance put in Motion, continued several successive Vibrations, resisting each Impress of the Atmosphere. But the Chief Remark in this Experiment was, that the Salient Water in the Receiver, formed several large Lines, some of which were Parabolical, when the Receiver was pretty well exhausted. EXPERIMENT V About the Production of Heat by Attraction in the exhausted Receiver. IT being the Opinion of some Learned Men, that the Incalescence of solid Bodies depends on the Attrition, or violent Agitation of the intercepted Air; To try how far this might be true, I caused a strong Spring of Iron or Steel (See Plate the Sixth, See Plate 6. Fig. 3. Fig. 3.) Figured much like the Lathe of a Cross-bow, to be fixed to a staple Trencher: On the upper Part of the Spring was fixed a Concave Piece of Brass, like a Burning-Glass, about 2 Inches Diameter, and moderately slender; to the Concave Superficies of which, was fixed a Convex Piece of the same Metal; which had a square Handle on the upper Part, to which was fixed a square piece of Wood, the other End being fixed to the Basis of a Wooden Pillar, made use instead of our Vertical Cylinder; and the upper End of this Pillar was fixed to the Turn-Key, being of such a Size, that when the Stopple was depressed into the Socket made in the Brass Cover, the Concave and Convex Superficies of the two Pieces of Brass, contained betwixt the Wooden Pillar and the Spring, were squeezed together, and the Spring in some measure expanded. All things being thus provided, and a Mercurial Gange conveyed into the Receiver, a Wimble was fixed to the Top of the Stopple, which being turned round for some time, and the Air being exhausted out of the Receiver, we presently took off the Cover; and perceived, that the contiguous Superficies of the Pieces of Brass, betwixt which we had laid some powdered Amel to make them move more easily one upon another, were sensibly warm. And the Experiment being repeated a second time, and the Air so far exhausted, that the Mercury was no further depressed, they grew so hot, that I could scarce endure to touch them; and a considerable Degree of Warmth succeeded, when the Experiment was tried with two Pieces of Wood, the one of Oak and the other of Beech. From which Experiment it appears, that Attrition of Solids may cause a considerable Warmth, when the Air betwixt their Superficies is exhausted. EXPERIMENT VI About the disjoining of two Marbles (not otherwise to be separated without a considerable Weight) upon a Removal of the Pressure of the Air in the Receiver. HAVING several times suspended two flat Polished Marbles, whose contiguous Superficies were moistened with Oil, to keep the Air from getting in betwixt them, upon a considerable Exsuction of the Air, they would sometimes fall asunder in the Receiver, at the eighteenth Suction, and sometimes at the eighth; tho' a Pound Weight was only suspended at the lower; yet in the open Air, where they were compressed by the ambient Atmosphere, they were able to sustain 80 Pound without separating. But having provided a Receiver with a Brass Conver (See Plate 6. Fig. 4.) and suspended two Contiguous Marbles in it, See Plate 6. Fig. 4. with a Weight of a few Ounces at the Bottom of the lowest, the String which suspended them being fixed to the Bottom of the Brass Stopple in the middle of the Cover by turning the Stopple, and by that means shortening the String, the Marbles were raised up in the Receiver, but upon drawing out the Air, they presently fell asunder; yet having so contrived the Matter, that the lower should not fall too far, the other was let down to it, and upon the Readmission of the Air, they were so closely compressed together again, that they could not be separated as easily as before: Yet if by turning the Stopple, the uppermost was raised before the Air was let in, it would leave the lowermost behind it. EXPERIMENT VII. A way to break Flat Glass speedily, by the Weight of the Atmosphere. TO make it appear, that the round Figure of a Body enables it to resist a more violent Pressure from the Atmosphere, than Bodies otherwise shaped; We made use of a Brass Hoop, about 3 Inches high, and 3 Inches and 2/10 in Diameter, and Cementing a round Piece of Glass upon the one Orifice, the other was joined to the Receiver with Cement; and upon drawing out the Air, the Atmosphere pressed so strongly upon the Glass, as to burst it asunder with a considerable Noise, like that of a Pistol. How far this may contribute to account for the Noise which accompanies the Explosion of Gunpowder in Pistols, we leave others to consider. EXPERIMENT VIII. The breaking of the Glass Plates in the foregoing Experiment may be accounted for without a Fuga Vacui. THAT the breaking of the Glass Plates did not depend on Nature's Abhorrency of a Vacuum, appears hence; for if instead of the former Brass Hoop, we make use of a Vessel Figured like a Conus Truncatus, or a Sugar-Loaf, the Cone being cut off; if the lower Orifice be large, and the upper not above an Inch Diameter, the Glass Plate Cemented to the larger Orifice, will break when the Receiver is exhausted; but if the smaller Orifice be upwards, the Glass Cemented to it will be whole; whereas did Nature's Abhorrency of a Vacuum cause the former, it would have the same Effect in the latter: Wherefore I rather think the Reason why the latter did not break as the former, was because a small Basis of the Atmosphere presses upon it, which it is. abler to resist than a larger Plate of Glass. EXPERIMENT IX. A Bladder burst by the Spring of the Included Air. NOT to mention, of what Advantage it might be, to have a Good Method to break Bladders filled with Air, in our exhausted Receiver, by supplying it with Air speedily, and without danger of letting in too much from without; I shall intimate, That if a blown Bladder be contained in an exhausted Receiver, the Internal Air will be so powerfully expanded, as to distend the Bladder, and stretch its Fibers, which when taken out again, and the Bladder at the Neck, being tied something nearer than before, the Bladder so distended with Air, and not liable to give way a second time to the Spring of the Included Air, the next time it is put into the Receiver, it is apt to burst. EXPERIMENT X. A Considerable Weight raised by the Spring of the Air included in a Bladder. TO show that the Force of the Air's Expansion is so great, that ¼ of a Bladder, being filled with it, is able to distend it so powerfully, as to swell it up, tho' a considerable Weight be tied to the Bottom of it, to keep it from Rising; we filled the fourth Part of a Bladder with Air, and tying the Upper Part of it to the Stopple, it was suspended in our Receiver, with a Weight suspended by a String, which was tied to the Bottom of it; where we observed, That upon the Exsuction of the Air, the Included Air expanded itself, and distending the Bladder shortened it so, as to raise 15 pound weight. And another Bladder, having both Ends tied to the Stopple, and a Weight suspended at the Middle, of no less than 28 pounds, the expanding Air raised that an Inch from the Bottom of the Receiver; but when the Air was again admitted into the Receiver, it fell down again. EXPERIMENT XI. Bubbles Hermetically sealed, broke by the Air included. HAving closed a Glass Bubble Hermetically sealed, in our Receiver, and pumped out the Air more than usually in such Experiments, about four Minutes after the Pump ceased to work, the Bubble unexpectly flew into so many pieces, and with such force, as to be broke against the sides of the Receiver, into a Powder as small as Sand: But this sort of Glass being capable of stretching a little before it breaks, may be a Reason why the Experiment does not always succeed, the Spring of the Air contained in it being weakened by that Expansion of the Bubble. EXPERIMENT XII. Trials representing the Force of the Spring of Vncompressed Air upon Staple Bodies. The I. TRIAL. HAving cemented a Glass Plate upon the Brass Hoop, mentioned in the Seventh Experiment, and joined the other Orifice of the Hoop with Cement to the Pump, upon that, a Large Receiver was fixed: So that the Hoop supplied the place of a Receiver, and the Receiver kept the Atmosphere from pressing upon it; yet, upon an Exsuction of the Air out of the Hoop, the Spring of that contained in the Receiver, broke the Glass Plate into an hundred pieces. The II. TRIAL. AND a Receiver shaped like a Tumbler, which was capable of containing only a sixth part of what the Large Receiver did, being made use of, the Spring of so small a Quantity of Air, presently shattered the Glass Plate in pieces. The III. TRIAL. The Force of the Air's Spring. BUT a Large square Glass capable of holding a Pound, being made use of instead of the Hoop and the Glass Plate, upon the Exsuction of the Air, it was broke in pieces, both when the Large Receiver was whelmed over it; and likewise, when a Receiver not much higher than itself was made use of. In which Experiments we observed, That the Air making a greater Pressure on the Sides of the Bottles, than the Top, first broke them. And it was further observed, in the last Experiments, that the Glasses did not fly in pieces, till some time after the last Exsuction. But lest it should be questioned, Whether the Glasses were broke by the Pressure of the Air in the Receiver, we repeated one of the former Trials, with the Brass Hoop, leaving a communication betwixt the Receiver, and the Cavity of the Hoop, a small Tube, whose Cavity was no wider than the Diameter of a Hair, being lodged in Part of the Cement; and upon plying the Pump, we found, that the Air, having a free tho' a small Vent out of the Receiver, did not break the Plate as before. Yet notwithstanding, if the Air be sucked out of the Hoop too fast, that in the Receiver, not finding quick Vent, will break the Glass Plate, the Pressure of the Air in the Receiver, being too strong to be balanced, by the Resistance of the Air in the Hoop: And for a like Reason a slender Pipe, blown at the Flame of a Candle, upon its first Removal into the Cold, hath its sides, if thin, squeezed nearer together, the Pressure of the Outward Air being greater than the Resistance of the Internal. EXPERIMENT XIII. Suction is able to raise Mercury no highier in Pipes than the Weight of the Atmosphere impels it. HAving fitted one End (see Plate 5. Fig. 2.) of a Brass bend Pipe to a Stop-cock, See Plate the 5. Fig. the 2. and the other End to the Top of a Cylindrical Glass Pipe, near 50 Inches long, the lower End of it was immersed in a Glass of stagnant Mercury: And tho' the Pump was set on work, yet was it not able to raise the Mercury above thirty Inches, by frequent and reiterated Suctions. But Water being substituted instead of Mercury, it risen, at the first Exsuction, to the Top of the Pipe; and when the Stop-cock was opened, it would run down through the Exhausting Brass Syphon. From whence it appears, that the Rise of Mercury depends not on Suction, or a Fuga vacui, whatever some Learned Men teach; but is raised by the weight of the Atmosphere; since a Baroscope consulted at the same time, made it appear, that the Atmosphere was able to suspend it at such a Height. And as this is an Argument against those that dispute for a Fuga Vacui; so it is against those that hold, that it depends upon the Attraction of a Rarified Substance in the Top of the Pipe; for tho' we could rarify the Air further, by continuing the Action of the Pump; yet the Mercury would not rise one jot higher. ANNOTATION. BUT the Syphon, here mentioned, being elsewhere made use of, it may be requisite to Observe: First, The Pipe which bends so much, is made of Metal, to make it less subject to break: Secondly, The End of it, which is joined to the Stop-cock, must be a little wider than any other Part, to admit the Shank of the Stop-cock: Thirdly, The Cement which joins the Brass Pipe and the Stop-cock, being apt to be lose; I rather make choice of one, to which a Stop-cock is fixed, together with a Glass Syphon, about 10 Inches high, (see Plate 5. Fig. 2. where the whole is represented). And tho' this Additional Glass makes the Experiment longer, and more tedious, yet it is more useful and secure. EXPERIMENT XIV. The different Heights to which the Liquors may be elevated by Suction, accordingly as their Specific Gravity varies. See Plate the Fifth, Fig. the Third. FROM Experiments already laid down, it appearing to what Height Mercury may be raised in a Tube; we may guests at what Height Water might be suspended, by considering that it is 14 times lighter than the former. But to be further satisfied, I caused a small Pipe, which branched itself into two (see Plate the 5th Fig. the 3d) So that a Cylinder being fixed to each Branch, the Liquors contained in the Vessels, in which the lower End of the Pipe was immersed, would rise proportionably as their Specific Gravity enabled them to resist the Pressure of the Atmosphere; which being done, and the Pump set on work, Water rose in one of the Cylinders to 42 Inches, and the Mercury in the other Tube not above 3 Inches; so that the Water was fourteen times higher than the Mercury. And to make the Experiment more satisfactory, we let Air into the Receiver, till the Water subsided to fourteen Inches, and at the same time the Mercury was sunk to about an Inch; for in this Experiment it was observed, That the Proportion was not so exact as 1 to 14 precisely Specifies, but thereabouts. From this Experiment, we may draw Arguments, not only against what is taught concerning Nature's Abhorrency of a Vacuum; but it may likewise more nicely inform us of the Specific Gravity of Liquors: For having put into one of the Vessels, under the Glass Tubes, Fresh Water, and into the other Salt Water; when the Fresh Water risen to 42 Inches, the Salt Water was but 40 Inches high. But having made use of a Brine, made of Sea-salt, melted in the Air, instead of Salt Water, when the Fresh Water was raised to 42 Inches, the Brine did not exceed seven. I likewise put into one of the Vessels, when this Experiment was over, a Solution of Pot-ashes, and Common Water into the other, and when the Water risen to 42 Inches, the Solution was raised but to 30. EXPERIMENT XV. To what Heights Water and Mercury may be raised proportionably to their Specific Gravities. HAving put Mercury into a Bottle, and poured Water into the Bottle upon the Mercury, we immersed one Pipe so low, as to have its End in the Mercury; and another Pipe was likewise immersed in the Water only; which being fixed by the help of a Cement in the Neck of the Bottle, the whole was conveyed into the Engine, and the Pipes being each divided into Inches, by hard Wax, with which they were marked, we observed, that the Water risen 15 times as high as the Quicksilver. EXPERIMENT XVI. The Former Experiment Illustrated. HAving put Mercury into a short Tube, and Water into one that was longer; both of them being Hermetically sealed at one End, we inverted them both, the End of each resting in a Distinct Vessel; which being conveyed into the Receiver, the Water in the Cylinder did not in the least subside, till by Pumping out the Air, the Mercury subsided within 3 Inches of the Bottom, which was sooner than it ought, according to Statical Rules, which we conceived to proceed from some Airy Parts, lodged in the Pores of the Water, which rising to the Top of the Cylinder depressed it by their Spring; yet the Water, when the Mercury subsided to the Height of an Inch, was near as high as before. EXPERIMENT XVII. The greatest Height to which Water may be raised by Suction, etc. TO try how high Water might be raised by Suction in a Pump, I provided a long Tube, about thirty Foot long, being made of several Tin Pipes, closely joined together with Soder, and covered over with a Black Cement; which, to keep it from sticking to our Hands, we covered with Plaster of Paris: To the upper End of this Pipe, was fixed a Glass Tube, about three Foot long; and to the Top of that was fixed another Pipe, consisting of two pieces, which made a right Angle with each other, part of which was Parallel to the Horizon, See Plate the Seventh. Fig. 1. and the other Perpendicular; the lower End being fixed to the Engine, which was placed upon a Flat-roofed House: And a Vessel filled with Water, being put under the End of the Pipe below, the Pump was set on work; and the Water, after a few Exsuctions, was raised to the middle of the Glass Tube, emitting several Bubbles, which proceeded from the Air, formerly lodged in the Pores of the Water. But the chief Aim of our Experiment, being only to try to what Height the Water could be raised, I caused the Pump to be nimbly plied, till the Water could rise no higher; which being done, and the Height of the Water measured by a String, we found it to be 33 Foot, and about six Inches; Quicksilver in a Baroscope, at the same time, standing at 29 Inches, and about 3 eights of an Inch; so that the Water was near fourteen times as high as the Mercury. In which Experiment, that the upper part of the Tube was sufficiently exhausted, appeared from several Circumstances; as First, If any Air got in at Crannies in the Pipe, it would rise in Bubbles, easily to be distinguished, from those which risen from the Pores of the Water; and tho' the Quantity of those Bubbles was considerable, yet more Air being thrown out by the Pump, than could get in, it must needs be empty enough. But, In this Experiment, it was to be noted, That when first the Water appeared in the Glass Tube, they would be very numerous, and form a Froth; yet, when the Pumping was further continued, they grew less and less: Secondly, we observed, that the Water made several Vibrations in its Rise; which, tho' near a Foot at the first, grew less and less. Thirdly, it may be observed, that the Baroscope, consulted before, some time after, was noted to have risen considerably; so that had the Experiment been repeated again, the Water would have been buoyed up a good deal higher. Now from this Experiment it appears, how improbable it is, what some Men teach concerning the Rise of Water, in Spiral Pipes, up to the Top of high Mountains; since it is evident, that it cannot be drawn higher than 36 Foot, by a Sucking Pump: EXPERIMENT XVIII. About the Bending of a Springy Body, in the Exhausted Receiver. TO be satisfied how much the Elasticity of Bodies depends on the Influence of the Air, I fixed one End of a Whale-bone in a Trencher, and tied a Weight to the other, by which it was bend, so low, as almost to touch the Plane under it. This being conveyed into our Receiver, upon the Exhausting of the Receiver, I could not perceive any Alteration. EXPERIMENT XIX. Concerning the making of Mercurial Gauges, whereby to estimate how much the Receiver is exhausted. SEveral Gauges have been made use of to discover, when the Receiver is well exhausted, as by suspending a Bladder, which is almost empty of Air, or by inverting a small Tube in which Spirit of Wine was contained; but the former taking up too much Room in the Receiver, and the latter not discovering whether the Receiver was exhausted, or not, till the Air contained was too much Rarefied, for any Considerable Observations; Therefore, to enable me to make more Observations in the several Degrees of the Receiver's Exsuction, I took a slender Pipe of Glass, about 10 Inches long, and as small as a Goose Quill, and having melted it at a flame, so as to soften it, and make it apt to be bend; I caused it to be put into the Form represented by (Plate 5. Fig. 4.) so that about an Inch of the lower Leg being filled with Air, See Plate 5● Fig. 4. and the rest of that, as well as the greatest Part of the short one, being filled with Quicksilver, the Expansion of that Air might easily be perceived, by pasting a Piece of Paper upon that Tube, divided into several exact Parts; for as the Receiver is more or less expanded, the Air in the longer Leg of the Gage, will be extended to some of those Marks; and if when the Air is so expanded, the Experimenter desires to know, at each of those Marks, how much the Receiver is exhausted, it will appear by letting in as much Water as the Capacity of the Receiver is able at that time to hold; so that if when the Air is at any determinate Mark, the Water be let in, and it appears, that the Air in the Receiver was so far Evacuated, by observing how much Water will be admitted, when the Air is expanded to each Mark; the Gage, for the future, will not only inform us, how much the Air is exhausted; but by the help of the small Gage, a larger may be made, by putting both into an exhausted Receiver at once, for by observing, when the Air is expanded to each Mark in the little one, how far it is expanded in the large one; we may learn, how much the Receiver is exhausted, for the future, by taking notice of the Expansion of the Air in the Leg of that larger Gage. And, This Gage is much more useful than some others: First, because the Mercury being a heavy Body, the Air, by expanding itself, is less apt to make it run over, or to make its way in the Form of Bubbles through the Mercurial Cylinder, as it would if other Fluids were made use of instead of it. Secondly, The longer Leg of the Gage is to be marked, by sticking Wax or Knobs of Glass to the Pipe, every Tenth being of a different Colour from the rest, at equal Distances from each other, which Divisions will be less subject to be rubbed off than Papers, which are also subject, in some Experiments, to be wet. Thirdly, The Leg of the Syphon in which the Air is included, may be either sealed up, before it is divided by the aforementioned Marks, or after, by drawing out the End of the Tube into a small Apex; and when about an Inch of the Pipe is filled with Air, it may be sealed up by blowing a Lamp Horizontally upon the Apex. Fourthly, Where very Nice Observations are to be made, and the Receiver admits of a longer Gage, instead of Mercury we may make use of a Tincture of Roses, or of Spirit of Wine with Cocheneel; in which, the Exsuction of the Air will be more nicely represented. Fifthly, We may vary the Mercurial Gage, by ordering the shorter Leg, so that it may have a Bubble about half an Inch Diameter, at an Inch distance from the Basis of that Leg, which Bubble must have a Pipe upon the upper Part of it to give way to the Air; which Bubble hath this Advantage above the other, that less Air may be contained in the Top of the longer Leg; since the Mercury not being capable of being raised so high, the Rarefaction of the included Air will be rendered more apt to be estimated by the Eye. Sixthly, This Gage is much more useful than those mentioned by other Authors, because it gives us an Account of the several Degrees of the Air's Rarefaction. EXPERIMENT XX. An easy way to make the Pressure of the Air sensible to the Touch. The Pressure of the Air sensible to the Touch. THE Pressure of the Air will be made sensible to the Touch, if a Tapering Tube of Brass, whose Cavity at one end is an Inch, and the other two Inches and an half wide, be fixed to the Pump instead of a Receiver; for if when the larger Orifice is Cemented on the Pump, one presses the Palm of ones Hand upon the smaller Orifice, and the Pump be set on Work, it will be a difficult Matter to take off ones Hand, and not a little painful; but the Pressure of the Incumbent Atmosphere will have a much more sensible Effect, if the larger Orifice be upwards instead of the smaller. EXPERIMENT XXI, About the subsiding of Mercury in the Tube of the Torrecellian Experiment, to the Level with the Superficies of the Stagnant Mercury. THE lower Part of the Ball of a Bolt-head being circularly cut off, we made use of it for a Receiver, including a Baroscope in it, and upon the first Exsuction, the Mercury subsided from 29 Inches to 9 or 10, and by three Exsuctions more, would be brought to a Level with the Stagnant Mercury, but would rise to its first Station again, as the Air was admitted in flower or faster. In which Experiment it is to be noted; First, that upon the first Exsuction, the Mercury was brought within an Inch of the Bottom, and continued several successive Vibrations before it settled at 10 Inches high. Secondly. If instead of drawing any out, Air be forced into the Receiver, it will raise the Mercury higher than it's former Station: Thirdly, The Receiver was so far exhausted, as to make the Mercury subside to a Level. EXPERIMENT XXII. In Tubes' open at both Ends, when Nature's Abhorrency of a Vacuum cannot be pretended, the Weight of Water will impel Quicksilver no higher in slender than in larger Pipes. The suspension of Quicksilver equal in small and wide Pipes. TO prove that the Weight of the Atmosphere, may buoy up Mercury equal in large as in smaller Tubes, I shall add the following Trials. The I. TRIAL. Having put as much Mercury into a Glass Tube, about two Foot and a half long, as reached 3 or 4 Fingers, the one End being sealed Hermetically; we hung two Tubes by Strings to the Top of the former, so that the lower Ends of them were immersed in the Mercury; which being done, we poured Water upon the Mercury, and observed the Mercury to be equally raised in the great Pipe, as in the little one, and the Water being sucked out, it proportionably subsided in each. The II. TRIAL. Having poured a Convenient Quantity of Quicksilver into a Tube of Glass, near a Foot long, and filled two Pipes of Mercury of an unequal Boar, the one End of each being Hermetically sealed, we immersed them in the large Tube, contriving to open the lower Orifice, when below the Stagnant Mercury; and I observed, that they not only both of them subsided to an equal Station; but Water being poured upon the Stagnant Mercury, the Weight of it buoyed them up both alike in the Tube, and the Water being successively sucked out, and put in again, the the Mercury in the Tube, proportionably fell and risen equally in both; no difference proceeding from the Wideness of their Diameters, in the Height of the Mercurial Cylinders. EXPERIMENT XXIII. At what Height Mercury Amalgamated with Tin, as well as pure Mercury, will be suspended. HAVING filled a Glass Tube with Mercury Amalgamated with Tin, and inverted it, it did not fall below 31 Inches. In trying this Experiment, the following Particulars are to be noted: First, That if the Amalgama be too thick, it will be apt to stick to the Tube, and will likewise hinder several Aerial Corpuscles from flying away. Secondly, From hence it may be observed, that as the Aequilibrium of Mercury, and the Atmosphere varies; so does its Ascent in such Tubes. Thirdly, It would not be amiss here to consider, whether these two Metals penetrate each others Dimensions, as I have observed Copper and Tin to do; and by forming a new Metalline Substance to render the Composition heavier than the Weight of the two single Ingredients. EXPERIMENT XXIV. A Method of making Barometers, which may be carried to distant Countries. TO make a Portable Barometer, we took a Cylinder about 4 or 5 Foot long, and having bend one End at the Flame of a Lamp, so as to make the shorter Leg about a fourth Part as long as the other, sealing up the End of the longer Leg, we injected Mercury into the shorter Leg by a Tunnel, till it was raised about 3 Inches in both Legs; which being done, and the Orifice of the shorter Leg being stopped with the Finger, we inclined the longer Leg, and so by successively filling the short Leg, and inclining it so as to make it run into the longer, we filled the longer Leg quite full of Mercury, and by inclining it several times afterward, and permitting the Bubble of Air, which usually lies at the Top of the sealed Head, to run through the Mercurial Cylinder backwards and forwards, we freed it from those Bubbles, which are usually in its Pores. But besides this way of filling the Pipe, we have, with less Trouble, done it by making use of a Tunnel; which, when the Pipe is a little inclined, reaching a little above the Flexure of the Syphon, will fill the Tube without much trouble: And the Pipe thus filled with Mercury may, by often erecting of it, and shaking the Pipe so erected, be freed from those Airy Particles which commonly lodge in the Pores of the Mercury. See the whole Barometer, Plat. 7. Fig. ig. 2. The Barometer being thus ordered, we contrived a Frame to carry it in, which was made of a Piece of Wood, in which a Gutter was cut for the Pipe to lie in; the lower End of the Frame being likewise so contrived, as to contain the short Leg of this Tube: The Pipe being lodged in this Gutter, we fixed a Cover to one side of the Frame, with little Highes; the other, when occasion required, being fastened with Hasps. And because the Motion the Mercury would be put into, would be apt to break the Pipe, were there too much Liberty given it to move in, or were there any Interstices betwixt the Pipe, and the Gutter it is lodged in; we took Care to lay Cotton both betwixt the Pipe and the Concave of the Frame, and betwixt the Cover and it; and that the empty Space which is usually above the Surface of the Mercury in Barometers, might not be prejudicial, we took Care to invert the Tube, and to fill the remaining Space unpossess'd with Mercury either with an Addition of Mercury or with Water, sealing up the Orifice of the shorter Tube Hermetically, till it came to be used again; and then, the Superflous Mercury, may be taken away by immersing a small Pipe in it; which, if the upper Orifice be stopped with one's Finger, will take away so much as the Cavity of the immersed Tube had received into it: But if Water be made use of, instead of Mercury, it may be licked up with a Sponge. And if by shaking of this Barometer in long Journeys any Particles should get out of the short Leg into the larger, by successively inverting the Tube, and permitting the Bubble of Air to pass backwards and forwards, the Mercury in the long Tube may easily be freed from Bubbles. Of what Use this Barometer may be, in discovering the Weight of the Atmosphere in long Journeys, both at Sea and at Land, I shall leave to others to consider; only I shall annex this Advertisement, that sometime after I made this Barometer, having carried it about 33 Miles I observed, that it did not rise by ¼ of an Inch as high as it did before; but whether it might be imputed to the narrowness of the Pipe, or any other Accident, I cannot yet determine. EXPERIMENT XXV. What Height the Mercury in Barometers will be suspended at, at the Top of Hills. Some Observations of the Height of Mountains, especially, the Picinino of Teneriff. HAVING observed the Height at which Mercury was suspended at the Bottom of a Hill, and compared it with a Barometer made the ordinary ways; it was observed, that the Height it was suspended at, at the Top of the Hill, was ¼ part of an Inch below the Mark it reached at the Latter; and as the Barometer was brought lower, the Mercury in the Pipe risen higher and higher: But if such Observations could be made at the Top and Bottom of the Mountain Teneriff, the Experiment would afford further Proof of our Hypothesis concerning the Air's Spring and Weight. An Appendix about the Height of Mountains. The Height of Mountains. NOtwithstanding some Ingenious Men have taught, that the Height of the Atmosphere is of stupendious, and others confine it to narrower Dimensions; yet, I shall add some Observations, which may confirm what we have taught concerning it; and tho', as Ricciolus takes notice, the Jesuit Rector Melensius says, that of all the Clouds, whose Height he measured, they did not exceed 5000 Paces, yet if we allow Meteors and Comets to arise from Terrene Exhalations, and that the Height of Clouds varies according to the different Degrees of the Air's Rarefaction, it will follow, that the Height of most of them exceeds what Carden and Kepler allow. But to proceed to what I have to relate concerning the Height of Mountains; I shall relate, what I have learned by Information. And first, the Ingenious Mr. Sydenham told me, that the Mountain Teneriff is so high, that the Top of it may be seen 60 Leagues off, and that he himself had discovered it at 40 Leagues distance like a blue Pyramid above the Clouds; and he likewise told me, that the Island of Madera might be seen from it, tho' 70 Leagues distant; and that the Great Canary seemed so near it, that one would think it possible to leap down upon it: And indeed, Ric●iolus observes, that it might be seen 4 Degrees distance; and Snellius also allows the Height of it to be Ten Miles; tho' I believe, that the way he takes to calculate the Height of it, may be none of the truest; he likewise by Refraction, judging the Mountain Caucasus to be 51 Bolonian Miles high, which is not believed probable; since the Mountain Teneriff hath been observed, by one who took its Height in a Ship at Sea, not to be above 7 Miles high in a Perpendicular Line, yet it is esteemed the highest Mountain in the World; tho' if what Aristotle and others report of Mount Caucasus, be true, there may be others much higher than those. For tho', if measured from the Foot, or Levelly of that piece of Ground, which they stand on, they may be lower, yet considering that the Ground they stand on, may be much more protuberant, from the Level Superficies of the whole Globe, they may be much higher upon that Account. EXPERIMENT XXVI. The Pressure of the Atmosphere may be able to keep up the Mercury in the Torrecellian Experiment, tho' the Air presses upon it, at a very small Orifice. IT being observed by several Learned Men, That Mercury is suspended at an equal height in a close Room, as in the open Atmosphere; to prove, that the Air having a Communication with the External, even at small Crannies, may have an equal Force, as if the Mercurial Cylinder was immediately subject to the whole Atmosphere; I shall add, That if the Tube, just before mentioned, for a Portable Barometer, be so drawn out at the Flame of a Lamp, that the Orifice is but about a tenth Part as big as before, the Mercury will be suspended at the usual Height; and the like will succeed, if instead of drawing the End of the Pipe out so, a Cork be put into the End of the Tube, leaving but a small part of the Orifice open to the Outward Air. EXPERIMENT XXVII. An Obliqne Pressure of the Atmosphere may be sufficient to keep up the Mercury at the usual Height, in the Torrecellain Experiment, and the Spring of a small quantity of Air may do the same. IF the the Shorter Leg of a Syphon, See Plate the 7th. Fig. the 3d. being bend, as represented by Fig. 3d. Plate the VIIth the Mercury be suspended at its usual Height, it appears that the Pressure of the Atmosphere hath as strong Effects, if the End of the Tube, through which it is conveyed, only admits of the Pressure of the Air, which it receives downwards. But if instead of being so bend, See Plate the 7th. Fig. the 4th. the End of the Shorter Leg be Hermetically sealed, as represented Fig. iv Plate the VII. the Mercury is sustained at its usual Height, it will appear, that the Spring of a small quantity of Air is able to bear up a Cylinder of Mercury. N. B. If the Tube thus Hermetically sealed, be shaken, the Mercury will form some Vibrations upon the Included Air; the Spring of it being compressed, and expanded again successively for a while. But the former of these Trials may be made in a Pipe, conveniently shapen before the Longer Leg is filled with Mercury, and the latter by stopping the Orifice with a Cork, and Close Cement, which may be pierced with a Wire, when this is used as a Baroscope; which way may be taken with a Travelling Baroscope. EXPERIMENT XXVIII. A Baroscope of use but at some times. TO show that the Suspension of Mercury in a Glass Tube, less than 30 Inches long, does not proceed from a Fuga Vacui, I caused one to be Hermetically sealed at one End, the Length of it being about two Foot and a half; and filled it with Mercury, a small quantity of Water being left upon it; and when the Atmosphere was much lighter, I found that the Mercury subsided, and that there appeared a small Bubble of Air in the Water, which being no bigger than a Pin's Head, was so far compressed before, as not to appear. EXPERIMENT XXIX. The Ascension of Liquors in very slender Pipes, in an Exhausted Receiver. HAving tinged Spirit of Wine with Cocheneel, which bubbled in the Exhausted Receiver, for some time, several slender Pipes being put into it, it risen highest in those whose Boar was narrowest; but when the Air was let in again, the Liquor in both subsided to a Level: But two Pipes of different Boars, being let down into that Liquor a second time, tho' it answered the former Trials in the Ascent; yet, the Surface in the slenderer Pipe, remained something above the other, when the Air was let in again. But what was more Remarkable, was, that tho' the Liquor in the Vessel, in this Trial, emitted no Bubbles, yet that in the Ends of the Tubes did; which were supposed to be caused by the sides of the Glass, they were contained in. EXPERIMENT XXX. When the Pressure of the External Air is taken off, it is very easy to draw up the Sucker of a Syringe, tho' the Hole at which the Water should succeed, be stopped. FOR a further Illustration of the Doctrine of the Spring and Weight of the Air, we made the following Trials. The I. TRIAL. We took a Syringe of Brass (see Plate 8th. Fig. 1st.) whose Barrel was about six Inches long, See Plate the 8th. Fig. 1st. and its Diameter about one Inch ⅜, and having fitted the Sucker to the Barrel of the Syringe, we stopped the lower Orifice of the Syringe, and tied a good Weight to it; which being done, we let it down into the Receiver, tying a String to the Sucker, and another End of that String to the Turning-Key in the Cover of the Receiver; where we observed, That tho' when the Receiver was exhausted, we could, by turning the Key, draw up the Sucker easily; yet, when the Air was admitted into the Receiver again, it could not be lifted up with a less Force, than what was sufficient to overpower the Pressure of the Atmosphere, or the Air contained in Receiver; but the Air being once let in, when the Sucker was raised to the Top of the Barrel, the Pressure of it was so violent, as, by forcing the Sucker down into the Barrel of the Syringe, to break the String, which was tied to the Turning-Key. The II. TRIAL. Being a Variation of the former. We took the former Syringe, and having tied a Weight, which weighed about two Pound and two Ounces, to the Sucker, we suspended it in our Receiver, the Orifice of the Barrel being first stopped with a Cork; and we observed, that after a few Exsuctions, the Weight drew down the Barrel of the Syringe; and when the Air was again let in, the Pressure of it raised it up much faster than it fell. But in this Experiment, it is to be noted, that if Air gets into the Barrel of the Sucker, whilst it is drawn down, it will not be raised quite so high again as before. And likewise, the Reason why it is requisite, that so large a Weight should be tied to draw it down, is because it must not only overpower the Pressure of the Air, but also the Straitness which requires a Force to make the Sucker move in the Barrel. Secondly, it is observed, that as the Weight did not overpower the Pressure of the Air, till a good deal was exhausted; so neither did it rise again, till a sufficient Quantity of Air was let in again. EXPERIMENT XXXI. About the opening of a Syringe, whose Pipe was stopped in the exhausted Receiver, and by the help of it, making the Pressure of the Air lift up a considerable Weight. HAving closed up the Hole at the Bottom of the Syringe, See Plate 8th. Fig. 2d. with good Cement, we tied a hollow piece of Iron to the Barrel, into which several Weights being put, we tied the Rammer to the Turn-Key; and tho', when the Receiver was exhausted, we could draw up the Rammer without the Syringe; yet, upon a Reingress of Air, the Syringe and the Weights would be raised swiftly up: So that so small a Cylinder of Air as equalled the Barrel of the Pipe, was able to lift up the Weight of sixteen Pounds. EXPERIMENT XXXII. The Sticking of Cupping Glasses depends on the Pressure of the Air. TO make it evident, See Plate 8th. Fig. 3d. that the Sticking of Cupping Glasses, and the Pain which they cause, proceeds from the Pressure of the Air, we provided a Receiver, and a Large Glass, such as Plate the 8th. Fig. 3d. delineates; I caused the Cupping Glass to be applied to a Young Man's Hand; which being done, and his Hand applied to the Top of the Receiver, instead of a Cover, the Lower Orifice of the Receiver, having first been cemented on the Pump, upon the first Exsuction of the Air, the Cupping Glass fell off his Hand, for want of the Pressure of the External Air, to press against it. EXPERIMENT XXXIII. TO illustrate the former Experiment, we took a Brass Hoop, mentioned in the Fifth Experiment, and stretching a Bladder upon the upper Orifice of it, as upon the Head of a Drum, we tied it up in the Middle of the lower Orifice, See Plate the 8th. Fig 4. and placing it upon a piece of Wood, which had a hole in the Middle for the Neck of the Bladder to hang through, we made several holes on the Lower Side of that Bladder; which being done, we suspended a Blind-head at the Turn-Key of our Receiver, and when the Receiver was exhausted, we let it down to the Bladder, and found, that when the Air was again admitted into the Receiver, the Pressure of it so pressed upon the Bladder, as to fix it fast to the Blind-head. But repeating the Experiment, and exhausting the Receiver more perfectly, we took out the Bladder thus fixed to the Blind-head, and having tied the Glass to the Hook of a good Statera, and likewise a large Scale to the Neck of the Bladder, and put in Weights into it, till they amounted to 35 Pound weight; then the Weight, over-poising the Pressure of the External Air, the Bladder fell off: But in this Experiment it was observed, See Plate the 8th. Fig. the 5th. that as the Weights in the Scales grew heavier and heavier, the Bladder seemed to be sucked more and more into the Receiver. EXPERIMENT XXXIV. Bellows whose Nose is very well stopped, will open of their own accord, when the Pressure of the External Air is taken off. AS an Argument of the great Force of the Air's Weight, it is observed, that when the Nose of a Pair of Bellows is stopped, it requires a Force able to overpower the Pressure of so large a Pillar of Air, as lies upon them, to open them; but when that Weight of the Atmosphere is taken off, the Spring of the Included Air is so strong, as to be able to raise and expand the Bellows of its own accord. To make this Evident, See Plate the 8th. Fig. the 6th. we caused a Pair of Bellows to be made, whose Board's were circular, and near 6 Inches Diameter, without a Valve, the Nose of them being about an Inch long, and the Leather limber: Which Bellows, when full of Air, seemed to be a Cylinder of about 18 Inches high. The Nose of these Bellows being stopped, when they were emptied of Air, we conveyed them into our Receiver, and observed, that when the Air was exhausted out of the Receiver, the Air contained in the Folds of the Bellows, and betwixt the two Bases lifted up the Higher a considerable Height. EXPERIMENT XXXV. An Attempt to examine the Motions and Sensibility of the Cartesian Materia Subtilis, or the Aether, with a Pair of Bellows, which were made of a Bladder, in the exhausted Receiver. IN order to try, whether there be any finer Substance than Air, in the exhausted Receiver, we contrived to make a Pair of Bellows of a Bladder, whose Bases were Paste-board, See Fig. the 7th. Plate the 8th. the upper being covered with a Plate of Pewter, to which was fixed a Leaden weight to press it down: Besides, over against the Nose of the Bellows, in which the Neck of the Bladder terminated, it was contrived, that the End of a Feather was fixed so, that if any Subtle Matter were forced out of the Bellows, it should discover itself by moving that Feather. The Bellows being thus provided, and the Pillars, to which the Feather is fastened, being joined to the upper Basis of the Bellows, with Cement, we fixed a Weight to the Lower Basis, and conveyed it into the Receiver; See Fig. the Eighth. where we observed, upon the exhausting of the Receiver, that the Air in the Bellows raised up the upper Basis, together with its Weight; and the Air rising out at the Vent, manifestly moved the Feather: But when the Receiver was quite exhausted, and the Weight upon the Upper Basis depressed it violently, we could not perceive that the Feather was in the least moved, and the like was observed upon repeating the Experiment. EXPERIMENT XXXVI. The great and seeming Spontaneous Ascent of Water, in a Pipe filled with a Compact Body, whose Particles are thought incapable of imbibing it. WE took a slender Pipe, and having tied a Linen-cloth to the jower Orifice, we filled it with Minium; and immerging it in Water in a Wide-mouthed Glass about an Inch, the Water ascended about 30 Inches; and the Experiment being again repeated in another, it risen 40 Inches. In which kind of Experiments, the following Particulars were to be observed: First, That other Powders being made use of instead of this, the Experiment did not succeed so well; nor was the Success much better, when we made use of Ink instead of Water. Secondly, Our Experiment succeeded the better, the finer and closer the Minium was: But if the Pipe be too small, the Event will not always be successful. Thirdly, We observed, That the Water ascends not to it's utmost, under 30 Hours, and sometimes longer. Fourthly, From hence it appears, That the Water in our Tube risen, without any swelling of the sides of the Tube, which some Learned Men ascribe the Cause of Water's Rising in Filtres to. Fifthly, From hence it may be urged, as probable, That the Sap in Trees may rise after the like manner, being promoted by Heat, and a due Texture of Parts. EXPERIMENT XXXVII. Of the seeming spontaneous Ascent of Salts, along the sides of Glasses, with a Conjecture at the Cause of it. I Have several times observed, that the watery Part of a Solution of Sea-Salt or Vitriol, being evaporated, the coagulated Salts would creep up the sides of wide-mouthed Glasses, in which the Solution was contained; and not only so, but if the Experiment were longer continued, they would rise over the sides of the Glass, and cover the external Superficies with a Crust of Salt. As for the Cause of so strange a Phaenomenon, tho' I will not be positive in it; yet, it may not improbably depend on the like Cause, as the Ascent of Water in the Tube, mentioned in the foregoing Experiment. For we may observe, that the Edges of Water are not only above the Superficies of the rest of the Water; but Sea-Salt as well as several others, crystallise at the Top of the Liquor they swim in, and near the sides of the Glass, their Coagulation being promoted by the Coldness of it; which Salts, when once the sides of the Glass is beset with them, the Water may rise to the Top, for the same Reason that it does in the slender Pipe before mentioned, and Salts carried up to the Top of those, and coagulating there, still lay a further Bottom for their Ascent; and so successively, till they rise to the Top of the Viol: And that there are Passages betwixt these saline Parts, for the Water to ascend through, appears; since they may be broke off in Flakes, separate from each other: And if it should be thought, that the Water in such an Ascent, would dissolve the Salt; it may be answered, that the Water being so much impregnated with Salt already, can imbibe no more; and consequently, for that Reason, when it runs down the outsides of the Vessels, coagulates by the way, being too thick and full of Salts to continue long fluid. EXPERIMENT XXXVIII. An Attempt to measure the Gravity of Cylinders of the Atmosphere, so that it may be known and expressed by common Weights. The Weight of a Pillar of Air of a determinate size. BEING desirous to know what was the Weight of an Atmospherical Cylinder of Air, of a determinate Diameter, I caused a Pipe to be made of Brass, whose Diameter was an Inch, and its Length three; one End of which being closed up with a Plate of Brass, I counterpoised it in a nice pair of Scales; and found, that it was able to contain about 137 Drachms 45 Grains of Mercury; which being multiplied by Ten, a Cylinder of Mercury of 30 Inches, and consequently an Atmospherical Cylinder able to counterpoise it, must amount to 12 Ounces and about 6 Drachms. And by weighing Water in this Tube, before the Mercury was put into it, the Water weighing 10 Drachms 15 Grains, the Proportion of Water to Mercury seemed as 13 18/41 to 1. But in estimating the Weight of a Cylindrical Pillar of Air, it may be here requisite to advertise, that I made use of a Brass Cylinder, because the Cavities of a Glass Tube are unfit for such an Experiment; since it is a hard thing to know, whether the Boar of such Tubes be equal throughout their Diameter. The Weight of a Cylinder of Mercury being thus found, it will not be very difficult to know, the Weight of a Cylinder of a different Diameter, by the Assistance of the Doctrine of Proportions and the 14th Proposition of the 12th Book of Euclids Elements. For since according to that, Cylinders of equal Bases, are to one another as to their Heights; and since, by the second Proposition of the same Element, such Circles as the Bases of Cylinders, are to one another as the Squares of their Diameters; and since Mercurial Cylinders will bear the same Proportion in Weights as they do in Bulk; The Rule will be, That as the Square of the Diameter of the Standard Cylinder, is to the Square of the Diameter of the Cylinder proposed, so will the Bulk of the former be to that of the latter; and the Weight of that to the Weight of this; so that the Square of one Inch being 1, and the Square of 2 being four, the Weight of the latter will be four times the Weight of the former. EXPERIMENT XXXIX. The Attractive Virtue of a Loadstone in the Exhausted Receiver. TO try how far the Account given of the Attraction of a Loadstone, depended on what some Modern Philosophers teach, viz. That the Effluvia of a Loadstone pressing away the Air betwixt the Body attracted, that Air helps the Attraction, by pressing against the opsite side of the Stone; We placed a vigorous Loadstone in our Receiver, having adapted a Cap of Steel to it, to the lower side of which, a Scale with 6 Ounces of Troy Weight was fixed, which being all the Loadstone, besides the Steel and the Scale was able to keep up (all which being suspended at a Button, which was on purpose on the inside of the Cover of the Receiver) we observed, that tho' the Receiver was exhausted as much again as in common Experiments; yet, the Loadstone sustained its Weight almost as firmly as before the Pump was plied; and the Reason why it was not altogether, was, the thinness of the Medium; since the Weight suspended must be heavier, when the Air which was nearer proportioned to their Weight was exhausted. FINIS. ADVERTISEMENT. THE Number of Sheets contained in this Volume, amounting to what the Booksellers think fit to answer the Price put upon it; And also, to make the succeeding Volume Proportionable, the next Volume gins with a Continuation of what our Author further delivers concerning the Air. The TABLE. A. ACCIDENTS no distinct Entities Pag. 3. Secondary Affections of Matter, what Pag. 8. The Effects of Natural Agents, how diversified Pag. 10,21. Considerations in order to the Doctrine of Alteration Pag. 13, 14. Alteration what Pag. 15, 16. Products of Art the Effects of Nature Pag. 59 An Acid may be turned into an Alkaly Pag. 90. The Air's Spring and Weight proved Pag. 166, 167, 311, 317. from thence to the End of this Volume. Objections, raised by Franciscus Linus, answered Pag. 393. The Actions of some Bodies depend on the Catholic Laws of the Universe 241. and the Established Laws of Nature Pag. 242. The Temper of the Air in Subterraneal Groves Pag. 256. The Air enclosed in the Receiver acts by Virtue of its Spring Pag. 315. What Weight is requisite to draw the Sucker down Ibid. The Air's Expansion in a Lamb's Bladder Pag. 317. — The Force of it Pag. 318, 371, 451. — It's Expansion measured Pag. 319, 320, 409. Whether Air be a Primogeneal Body Pag. 341. The Air's Gravity and Expansion under Water Pag. 351. The weight of the Atmosphere considered Pag. 360. Why Air is indisposed to pass through Pores, which Water will Pag. 370. Proportion betwixt the weight of the Air and Water Pag. 372. — beewixt it and Mercury Pag. 374. The Height of the Atmosphere considered Pag. 372. The Tunicular Hypothesis examined Pag. 398. A Table of the Air's Condensation Pag. 411. — of its Rarefaction Pag. 413. Why Air condensed by Cold does not raise Mercury equally, as when condensed by Pressure Pag. 415. Why Animals die in the Exhausted Receiver Pag. 430. The Air's Pressure on Bodies contained in it Pag. 431. The weight of a Pillar of Air of a Determinate Size Pag. 480. The Air's Pressure sensible to the Touch Pag. 461. B. A Bitter Substance may become sour Pag. 96. The Expansive Force of steeped Beans Pag. 243, 244. A Bubble broke in the exhausted Receiver Pag. 450. A Bladder broke by the Air's Expansion Pag. 449. A Portable Barometer Pag. 465 C. Colours no Inherent Qualities Pag. 9 Considerations in order to the Doctrine of Corruption Pag. 13, 14. Corruption what Pag. 15. Similar Colours not Arguments of Similar Substances adequately Pag. 24, 25. The Chemist's Doctrine refuted Pag. 100, 112. Motion in the Parts of Consistent Bodies Pag. 144. Colours exhibited by Reflection Pag. 151, 153. Camphire dissolved in Oil of Vitriol Pag. 188. A Concrete the Result of a Mixture of Spirit of Wine, and a Solution of Coral Pag. 196, 197. The different Temper of Climates Pag. 252. Observations concerning Coral Pag. 272. Of the Flame of a Candle in the Exhausted Receiver Pag. 323. Concerning Live Coals, etc. Ibid. Corrosives, their Effects Pag. 390. Cupping Glasses, how they operate Pag. 474. D. Motion in the Parts of Diamonds Pag. 205, 206. E. Eggs how Hatched Pag. 73. A strange sort of Earth Pag. 196. The Temperature of the Regions of the Earth Pag. 256. — of the First Pag. 257. — of the Second Pag. 259. — of the Third Pag. 261. Why the Middle Region is coldest Pag. 259. The Pneumatick Engine described Pag. 307. — The Method of managing it Pag. 310. Elasticity explained Pag. 418. The Pneumatick Engine made use of in the First continuation described Pag. 435. F. Forms what Pag. 11. — Their Effects whence Pag. 12. The Doctrine of Substantial Forms considered Pag. 29. Forms not reduced out of the Power of Matter Pag. 30. The Aristotelian Doctrine of Forms contrary to Reason Pag. 31. Their Arguments considered Pag. 32, 33. Substantial Forms no Causes of Adhesion Pag. 34, 35. A Compound Form what Pag. 36, 41. The Doctrine of Subordinate Forms considered Pag. 37. Subordinate Forms proved. Pag. 38. A Compound Form what Pag. 39 Specific Forms considered Pag. 40. 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, hard to be distinguished amongst the Forms of Natural Bodies Pag. 41, 50. How distinguished Pag. 51, 55. Subordinate Forms act, how Pag. 42, 43. Subordinate Forms in Inanimate Bodies Pag. 49, 52. A Superadded Form its Effects Pag. 53. Concurrent and Subordinate Forms how distinguished Pag. 56. Subordinate Forms not necessary to Discriminate Bodies Pag. 67. Fluidity, it's Definition Pag. 115. What is requisite to render Bodies Fluid Pag. 116, 119, 120, 121, 193, 434. All Bodies not equally inclined to Fluidity Pag. 117, 118. What the Motion of the Parts of Fluids' depends on Pag. 124. The Superficial Figures of Fluids' Pag. 142. — of a Nitrous Liquor Pag. 146. — of Water Ibid. — of Oil of Turpentine Pag. 147, 151. — of a Solution of Tartar Ibid. — of Oil of Cloves Ibid. — of Quicksilver Pag. 148. — of a Nitrous Liquor, and Spirit of Wine Pag. 150. — of Oil of Aniseeds Pag. 153. — of Water included in Oil Pag. 155. — of Oil of Turpentine upon Cloves Ibid. — of Oil of Aniseeds coagulated Pag. 155. — of several other Mixtures Pag. 156, 157. A Fluid turned Solid Pag. 180. Fluids not divisible into Fluid Parts, as Quantity into Quantity Pag. 183. Subterraneal Fires, their Effects Pag. 262. Filtration, it's Cause Pag. 365. G. Considerations in order to the Doctrine of Generation Pag. 13, 14. Generation what Pag. 15. Gunpowder its Ingredients Pag. 67 Phaenomena afforded by a Gummy Substance, in Vacuo Boyliano Pag. 154. Solidity of Glass depends on a Juxta-position of Parts Pag. 162. The Parts of Glass in Motion Pag. 207, 208, 209. What Figured Glasses best resist the Pressure of the Air Pag. 320, 321. Gunpowder exploded in Vacuo Boyliano, etc. Pag. 328. Glass Plates broke in the Exhausted Receiver Pag. 448. Flat Glasses broke in the Exhausted Receiver Pag. 447. H. Heat no Inherent Quality Pag. 9 Heat what Ibid. Humidity a Relative Quality Pag. 125. Heat unusual in Mines whence Pag. 263. Heat produced by Attrition Pag. 445. I. Juxta-position of Parts not the only cause of Cohesion Pag. 160. Juxta-position of Parts promoted by the Air's Spring Pag. 161. — proved by the Cohesion of Polished Glasses Pag. 163. — by the Cohesion of Polished Marbles Pag. 164, 165, 166. The Interposition of Minute Parts may turn a Liquor into a Solid Pag. 178. Observations of Indurated Bodies. Pag. 191. — of the Bone of a Deer's Hart Pag. 192. The Effects of a Bar of Iron held to a Mariner's Compass, in a Perpendicular posture Pag. 202. Iron, how it acquires Magnetical Virtues Pag. 246. L. The Motion of the Parts of Liquids' variously determined Pag. 126, 127, 128, 140. — proved by a Solution of Sugar in Water Pag. 126. — by a Solution of Salt of Tartar Pag. 127. — by Lead raised in the Form of Vapours Pag. 128. — by drooping Oil of Turpentine upon Spirit of Wine Pag. 139. — by opening the Body of Copper with Sal Armoniac, and applying it to a Candle Pag. 141. Liquids', why sometimes unapt to mix with each other Ibid. A Diaphanous and Opacous Body afforded by a Liquid Pag. 143. The Superficies of Liquors, in Vacuo Boyliano Pag. 148. A Liquor may become consistent, by the mixture of a Powder Pag. 179. The Effects of a Loadstone upon Filings of Iron Pag. 293. M. Matter defined Pag. 2. Motion, a Catholic Agent Ibid. — Guided by God in the Creation Ibid. Mechanical Affections, their result Pag. 7. Mixture and Texture, how different Pag. 22. The Effects of Motion various Pag. 23. Modification, twofold Pag. 44, 45. — In what Respects Pag. 47, 48. Medicines Chemical, laid aside too rashly Pag. 113, 114. The Effects of languid and unheeded Motion, from Pag. 210 to 238. Motion, may be propagated through different Me diums Pag. 223. An Observation concerning Manna Pag. 253. Concerning a Match, burning in the Receiver Pag. 325. Why Mercury is not always suspended at the same Height Pag. 334. Marbles disjoined in the exhausted Receiver Pag. 446. Mountains, their Height Pag. 468. N. Nature, may not be always exact in her Laws Pag. 255. Natural and Preternatural States of Bodies not rightly stated Pag. 302. The natural Sat of the Air, a forced State Pag. 304. O. Odours, no inherent Quality Pag. 9 Odours, what Ibid. Observations about Lignum Vitae Pag. 103. Observations made in Quarries Pag. 104. P. Primary Affections of Matter Pag. 3. Putrefaction, what Pag. 16. Corpuscularian Principles very fertile Pag. 21, 22. Minuteness of Pores no Arguments of their Nonexistence Pag. 125. A Plastic Power inherent in Bodies Pag. 189. Plastic Power, what Pag. 190. Petrification, how effected Pag. 194, 195. Q. Qualities, no distinct Entities Pag. 3. Qualities, the Result of Modification Pag. 5. — Proved Pag. 6. Qualities, act how Pag. 11. Complexion of Qualities no real Qualities Pag. 17. Whether Qualities depend on substantial Forms Pag. 18. Qualities of a Compound, different from the Ingredients Pag. 19 Some Qualities, the Result of mixture Ibid. Qualities, how altered Pag. 20, 182. Different Qualities in Homogeneous Bodies Pag. 26. — Exhibited by Venice Turpentine Pag. 27. — By putrified Urine Pag. 27. New Qualities added upon a Dissolution of the Specific Form Pag. 46. Qualities, the Result of Motion, etc. Pag. 73, 74, 76, 77. Various Qualities produced, by a Change of Texture, in Camphire Pag. 78, 79, 80. — In Copper and Silver Pag. 81, 82, 83, 84, 85. — In preparing of Luna Cornea Pag. 86, 87. — In preparing of a Peculiar Salt Pag. 88 — By digesting Spirit of Nitre with Sea-Salt Pag. 89, 90. — By distilling Oil of Vitriol with Nitre Pag. 91, 92. — By digesting Spirit of Wine and Oil of Vitriol together Pag. 102, 103. — By a Redintegration of Salt Petre Pag. 108, 109. R. Redintegrations of Bodies considered Pag. 69. — Of Amber Pag. 70. — Of Roch Allom Ibid. — Of Vitriol Pag. 71, 72. — Of Antimony and Oil of Vitriol Ibid. — Of Salt Petre Pag. 105, 106, 107. The Signification of the Word Rest, limited Pag. 198. Of Respiration Pag. 382. The Aristotelian Rarefaction examined Pag. 404. Rarefaction explained Pag. 416. — According to the Doctrine of the Plenists Pag. 417. The Rota Aristotelica explained Pag. 419, 420. S. Sounds, no Inherent Qualities Pag. 9 Sounds, what Ibid. Species of Bodies, how distinguished Pag. 57, 58. Salts, their Figures how accounted for Pag. 62. Salts obtained from an Alkaly Pag. 63. — From Oil of Vitriol and a Solution of Sea-Salt Ibid. — From a mixture of Spirit of Wine and Nitre Ib. — From a Solution of Copper Pag. 64. — From Gold Pag. 65. — Venetian Borax Ibid. — Spirit of Urine and Nitre Pag. 66. — Soot and Sal Armoniac Ibid. — Spirit of Nitre and Pot-Ashes Pag. 68 Salt Petre obtained from Pot-Ashes Pag. 107. — Aqua Fortis and Salt of Tartar Ibid. Solidity refined Pag. 158. What is requisite to Solidity or Firmness Pag. 158, 159, 160, 161, 168, 169, 170, 171, 172, 173, 174, 176, 177, 178, 179, 181, 184, 185, 186, 187. A Solid turned Fluid Pag. 180. Motion in the Parts of Solids Pag. 200, 201. Cosmical Suspicions, from Pag. 249, to 256. The Temper of Submarine Regions Pag. 266. — Of the uppermost Ibid. — Of the lower Pag. 267, 268. The Bottom of the Sea unequal Pag. 279. — Undisturbed in Storms Pag. 271. — Almost stagnates Ibid. The Proportion of Salt in the Sea to the Water Pag. 275, 282, 283, 284. Springs in the Bottom of the Sea Ibid. The Reason of the Saltness of the Sea Pag. 278, 279. — It's Bitterness, whence Pag. 280. Concerning the Propagation of Sounds Pag. 353. A Spring bend in the exhausted Receiver Pag. 458. To what Height Water will be raised by Suction Pag. 452, 454, 456. T. Transmutation of Metals not impossible Pag. 94, 95. The Texture of their Liquids contributes to their Mixture Pag. 175. The Texture of Bodies enables them to work on each other Pag. 247. Trees under Water Pag. 273. V Union, the Cause of the Effects of Compounds Pag. 44, 51. Vitriol, Natural and Artificial agree in Qualities Pag. 60, 61. Vitriol turned into Allom Pag. 68 Vortices, beyond the Concave Surface of the Firmament Pag. 256. Of a Vacuum Pag. 331, 362, 440. Vapours and Fumes, why they ascend Pag. 356. W. Water acquires new Qualities by an Alteration of its Form Pag. 76. Water Convertible into Earth Pag. 98, 99 — How it becomes Solid Powder Pag. 99 An insipid Water drawn from Spirit of Vinegar and Salt of Tartar Pag. 188. Water its Gravitation Pag. 270. Agitation requisite to keep Water from stinking Pag. 281. Memoirs for the Natural History of Mineral Waters Pag. 286. The different Weight of Mineral Waters Pag. 291. — Observations requisite in trying them Pag. 295. Whether they have Arsenic in them Pag. 296. What Proportion of Salt they afford Pag. 299. Of the Elater of Water Pag. 337. It depends on the Elater of the Air contained in the Pores of it Pag. 339. Water hot, its spontaneous Ebullition Pag. 391. The END ADVERTISEMENT. THis Volume containing an Epitome of several of the Author's Works; I think it necessary to advertise, that to avoid a Repetition of all the Titles prefixed to the Tracts Printed severally; I have digested each of those Books into such a Method as they would have been probably Printed in, had they been all writ by our Author at one time; each Book being contained in Chapters, the Titles of which, will acquaint the Reader what Tracts they belong to: And that the Reader may be more clearly satisfied, I intent at the End of the next Volume, to add such a Table of the Author's Works, as shall readily direct what Chapters each Book is abridged in, by referring to them. IMPRIMATUR Liber Cui Titulus, THE WORKS Of the HONOURABLE ROBERT BOIL Esq EPITOMISED By RICHARD BOULTON. JOHN HOSKYNS, V P. R. S. Vicesimo Septimo Martii, 1699, THE WORKS OF THE HONOURABLE Robert Boil, Esq EPITOMISED. VOL. II. BY RICHARD BOULTON, of Brazen-Nose College in Oxford. Illustrated with COPPER PLATES. LONDON: Printed for J. Phillip's at the King's- Arms, and J. Taylor at the Ship in St. Paul's Churchyard, MDCC. To His Excellency The Most Illustrious PRINCE, CHARLES Duke of BOLTON, Marquis of Winchester, Earl of Wiltshire, and Baron St. John of Basin; the Premier Marquis of England; one of the Lords Justices of the Kingdom of Ireland; Lord Lieutenant and Custos Rotulorum for the Counties of Dorset and Southampton, the Town of Southampton and County of the same; Vice-Admiral of Southampton and the Isle of Wight; Lord Warden of the New Forest in Hantshire, and one of the Lords of His Majesty's most Honourable Privy-Council. May it please Your Excellency, SInce nothing contributes more to the Advancement of Natural Knowledge, than the Encouragement of great and eminent Persons; not only Custom but Interest hath generally inclined those, who employ their time in the pursuit of it, to shelter the Fruits of their Labours under the Protection of noble Patrons: For as there can be no greater Motives to Virtue and Morality, than the Favour of an Omnipotent Power; so in the Affairs of this World, we are most inclined to pursue, whatever may deserve the Esteem of great Men, or lead us into their Favour. And if the Tree of Knowledge flourishes most under the favourable Patronage of Princes, the Interest of, Learning will, at the same time, be a good Plea to extenuate my Presumption, and a great Argument why I should lay this at your Excellency's Feet. For, Illustrious SIR, whilst amongst the happy Number of His Majesties Favourites, we behold Your Excellency dignified with Titles of Honour, at the same time we are surprised to see, that no Titles can be so great but Your Excellency's Character adds a Lustre to, and increases the Dignity of them: A character! which, could I convey it down to future Ages, I must be able to represent, in the most lively Colours, All the Virtues of a good and pious Christian; the meek and liberal Temper of a Puissant and Noble Prince; the Wisdom of a Counsellor, and the Qualifications of one, to whose Judgement and Sagacity the Administration of the Government of a Kingdom hath been, in a great measure, committed, by the most Judicious and Sagacious of Kings. But, Illustrious SIR, since the draught of so Noble a Character as Your Excellency's is too hard a Task for a Pen better qualified than mine, I have sufficient reason to decline it; and shall rather reflect on the Happiness of this Kingdom, whilst so Great a King hath made choice of so Wise a Counsellor; and the great Felicity of the Commonwealth of Learning, whilst under the Patronage of so Illustrious a Prince as the Duke of BOLTON; and particularly on my own Happiness under Your Excellency's Protection, which is the more augmented by this opportunity of professing myself, Most Illustrious SIR, Your Excellency's Most Humble and Devoted Servant, Richard Boulton. THE PREFACE TO THE READER. THE candid Acceptance of the former Volume, and the favourable Approbation of the Learned, having given the Booksellers sufficient Encouragement to proceed in Printing the two subsequent Volumes; there is no need that I should, on their part, enlarge on the Subject of the Preface annexed to the first Volume, to show the Usefulness of the Design; since the general Consent of the Learned hath already put that beyond Doubt. Therefore, having laid down the Reasons why I proceeded in such a Method as I have placed the Subjects in, in the first Volume, in the latter end of that Preface, I shall, without increasing the bulk of this Volume with a long Preface, briefly subjoin the Rationale of this; And, First, The first Volume ending with an Epitome of the Honourable Author's first Continuation of Physicomechanical Experiments, I have begun this with some Experiments belonging to that first Continuation, and to them I have subjoined his second Continuation; to which, by reason of some affinity betwixt particular Experiments that Treatise and another, delivered in another Tract, I have added a Chapter of Observations on Animals included in Vacuo; and another relating to the same Subject, out of the Philosophical Transactions: And because these Observations engage our Thoughts in several things relating to the precedent Phaenomena of the Vacuum Boylianum, and may remind us of what he bathe delivered of the Spring and Weight of the Air, I have in the next place laid down his Animadversions on Mr. Hobbes Problemata de Vacuo, his Discourse of Attraction by Suction, and what he hath delivered concerning the Barometer in the Philosophical Transactions. And forasmuch as in all his Physicomechanical, and other Experiments already delivered, and tried in Vacuo Boyliano, we have several instances of the Rarefaction and Condensation of the Air, etc. hoping it would help some to a seasonable Reflection on what was before delivered; I have added what he hath taught concerning the admirable Rarefaction of the Air, and the Duration of its Spring; as also concerning its Condensation and admirable different Extension, when rarified and compressed: And since these Subjects renew our Considerations concerning the Spring of the Air, I have added further, a Chapter of the Weakened Spring of the Air, out of the Philosophical Transactions. And because the Spring and weight of the Air and their Effects, are not the only Qualities and Considerations to be taken notice of in the Atmosphere, from those I proceed to deliver what he hath Taught concerning Hygroscopes and their Utilities; as also what he hath writ of the Efficacy of the Airs Moisture: And because there are several Qualities in the Air which not only affect our outward Senses, but have a manifest Influence on the Mass of Humours which circulate in our Bodies, and on whose Tempers the Preservation or Distempers of a human Body depends, I have added what he hath delivered concerning the Salubrity and Insalubrity of the Air, whose variations in Temperature, altar the Constitution of the Humours of our Bodies. And since we are not only affected by manifest Qualities of the Air, but also by occult ones, I have laid down what our Author hath said on that Subject: and since Magnetical and Electrical Qualities are generally accounted Occult ones, I have added his Tracts on those Subjects. And to conclude the Third Book, I have added his General History of the Air, which I have therefore placed the last relating to that Element, because it consists of several Fragments which belong to several of the preceding Subjects, or bear a relation to some others which follow, concerning Colours, Tastes, and Odours. And having thus ended the Third Book, the Fourth contains those Subjects which have a more immediate Relation to the Outward Senses, and are considered as their Objects; which I therefore for distinction sake place together: Of which what our Author hath delivered concerning the Mechanical Production of Tastes, Odours, and Colours, I have laid down in this Volume, and shall proceed to the remaining Objects of our Senses, in the Third Volume; where I shall give a short Account of the Method I take in that, and in the mean time subscribe myself the candid Readers Very humble Servant, R. Boulton. London, Octob. 13. 1699. Vol. II. Plate. 1 Fig: 1. pag. 4. Fig: 3. pag. 5. Fig: 4. pag 6. Fig: 2. pag. 2. Vol. II. Plate. 2. Fig: 4. p: 14 Fig: 1. p: 8. Fig: 5 p: 17. Fig: 3. Fig: 2. p: 14. Vol. II. Plate. 3. Fig: 2. p: 22. Fig: 1 p: 21. Vol. II. Plate .4. Fig: 3. p: 27. & .29. Fig: 4. p: 29: p: 23. Fig: 1. Fig: 2. p: 25. Plate .5. Vol. II. Fig: 1. p: 32. Fig: 5. p: 485. Fig: 3. p: 32. Fig: 2. p: 32. Fig: 4. p: 33. Plate .6. Vol: II. Fig: 1 p: 33. Fig: 3. p: 35. Fig: 5. p: 366. Fig: 2 p: 34. Fig: 4. p: 365. Plate .7. Vol: II. Fig: 1. p: 35. Fig: 2. p: 37. Fig: 4 p: 374 Fig: p: 334 THE WORKS Of the HONOURABLE ROBERT BOIL Esq EPITOMISED. BOOK III. CHAP. I. Experiments touching the Spring and Weight of the Air, etc. THE Bulk of the former Volume, forbidding that I should add any more of the Experiments concerning the Air's Spring and Weight, I shall now proceed to lay down what our Author hath further delivered in his first Continuation of Experiments relating to that Subject. EXPERIMENT I. The Cause of the Ascension of Liquors in Syringes is to be derived from the Pressure of the Air. AS in the Experiments recited in the former Volume, it appeared, that the Pressure of the External Air, occasions the Difficulty of drawing up the Sucker of a Syringe; so I shall now show, that the Pressure of the External Air, upon the Surface of the Water, in which the Syringe is immersed, causes it to ascend, when the Sucker is drawn up. TRIAL I. Having cemented a Glass Pipe to the lower End of a Syringe, and immersed the lower End of that Pipe in a Viol which contained Mercury, we tied the Sucker of the Syringe to the Stopple which is in the Cover of the Receiver, and having conveyed it into such a Receiver as Fig. 2. Plate 1. Represents; See Plate 1. Fig. 2. we observed, that upon drawing up the Sucker, the Mercury did not in the least ascend, till the Air was let into it, and then it ascended up to the Top of the Glass Tube: And this Experiment being varied, by drawing the Sucker up an Inch before the Receiver was exhausted, the Mercury risen to the Top of the Glass Tube, tho' it did not in the least rise when the Sucker was drawn up as high again, after the Receiver was exhausted. And in trying this Experiment it was further to be noted, that when the Receiver was exhausted, it was as difficult to raise the Sucker, as when the End of the Syringe was stopped, the remaining Air which was able to keep the Sucker from rising, being unable to raise the Mercury. TRIAL II. Being a Prosecution of the former. The former Trial being again repeated, besides what we observed in that Experiment, we further noted, that a considerable Weight being tied to the Syringe to keep it steady and firm, the Mercury did not rise till we permitted the Air to return again into the Receiver, tho' the Sucker was raised two Inches. But lest the Phaenomena exhibited by these Experiments, should be influenced by the Air contained in the Glass Pipe; I caused the Pipe to be filled with Spirit of Wine, and immersed it in a Viol which contained the same Liquor tinged with Cocheneel; and observed, that though, when the Receiver was exhausted, the Liquor afforded Bubbles plentifully, and at the Top seemed to boil, yet it did not ascend in the least, notwithstanding the Sucker was raised two Inches and a half: But when the Air was let into the Receiver again, it ascended into the Body of the Syringe, which appeared, by the small Quantity of Spirit remaining in the Bottle, in which the Glass Tube was immersed. EXPERIMENT II. An Attempt to discover the Motion of Aether in the Exhausted Receiver. HAving instead of the Glass Tube mentioned in the former Experiment, provided a crooked one of Brass, See Plate 1. Fig. 1. such as the first Figure represents, and joined a Glass Tube to the shorter Leg with Cement, we caused Weights to be fixed to the Top of the Sucker to depress it speedily when occasion required: This Syringe was fixed to a Pedestal to keep it firm, and to hinder it from tottering; and a Feather was likewise fixed with Cement to the lower End of the Syringe, so that the small End was placed above the Orifice of the crooked Tube. All which being conveyed into a Receiver, and the Pump set on Work, we observed, that, the Sucker by the help of the Turning-Key being often elevated and permitted to fall again, the Feather was gradually less shaken, with what was forced out of the Syringe, as the Receiver was more and more exhausted, till at the last the Feather did not seem in the least to be moved, before Air was again let in, and then it was blown up as before: In which Experiment we observed, that as the Cavity of the Receiver was more or less exhausted, the Descent of the Sucker was accordingly quickened, so that had there been a Substance finer than Air in the Receiver, the Blast would have been greater as the Descent of the Sucker was swifter. We tried the same Experiment a second time, contriving to draw up the Sucker higher than we did before, but the Event was no more satisfactory than the former. But that I might be informed, what Quantity of Air was drawn out every Exsuction, as well as when the Feather was more or less shaken by the Wind thrown out of the Syringe, I made use of a Glass Tube, such as Figure the Third represents, See Plate 1. Fig. 3. instead of the former Brazen One; and the one End being immersed in a Jar, and placed in the Receiver, as the Air was pumped out, several Bubbles broke through the Water out of the Pipe, but External Air getting in at a Leak, the Water was pressed up into the Pipe again; nevertheless, upon an Exsuction of that Air it again subsided; yet yielded so many Bubbles, that we could not conveniently make any further Observations, till the Receiver having stood still for some time, the Water was freed from Air; and then, tho' the Pump was set on Work, till the Gage discovered the Receiver to be very well exhausted; yet we could not discern, that any Bubbles were forced through the Water in the Bottom of the Tube by frequently elevating and depressing the Sucker; for tho' there appeared a few in the Top of the Water, yet we judged that those rather proceeded from some airy Particles lodging in the Pores of the Water. But what was most Remarkable in this Experiment was, that after some time the Water rising about an Inch in the Tube, above the Surface of the Water without it, we several times raised the Sucker 2 or 3 Inches, and suffered it to fall again, without perceiving, that the Water in the Tube was in the least Affected; which is an Argument either of a Vacuum, or that the Parts of that Aether are so fine, that they exceed the Rarefaction of the Air so far, as not to be able to effect what a Particle of Air does which is not above 1/500 part of the Quantity of a Pin's head; a Particle of Air, before Expansion, of that Minuteness being able, when the Receiver is exhausted, to displace much more Water upon their Expansion than this Aether. By which Experiment, as well as what we have taken notice of, the Reason I formerly assigned for the rising of Water in Syphons seems to be confirmed; the Water in the Pipe made use of in these Experiments, not being able to rise when the Air was exhausted, tho' the Sucker was drawn up, till Air was permitted to enter into the Receiver again. EXPERIMENT III. Concerning the falling of a light Body in the Exhausted Receiver, the Figure of it disposing its Motion to be visibly altered by a small Resistance of the Air. TO discover whether so light Bodies as Feathers would be affected in their descent in the exhausted Receiver by any subtle Matter contained in it, we fixed a small pair of Tobacco-Tongs in such a Receiver as Fig. the Fourth Represents, See Plate 1. Fig. 4. which was 22 Inches high, and having joined four Feathers together with Cement, so as to lie across each other, we fixed a small piece of Paper to them, which being held in the Tongues, the Feathers hung in an horizontal Posture; And upon an Exsuction of the Air out of the Receiver, till by a Mercurial Gage it seemed void of Air, we opened the Tongues, by turning the Stopple in the Cover of the Receiver, (a short String, the one End of which was fixed to the Stopple, and the other to the Tongues, being by that means shortened) upon which we observed, that tho' these Feathers turned several times in the unexhausted Receiver, yet the Experiment being often repeated, we could not perceive them in the least to turn in the exhausted Receiver, but to fall like a dead Weight; and what was further to be observed was, that the Descent of the Feathers was much quicker in the exhausted Receiver, than when it was full of Air. Yet in this Experiment it was observed, that the Phaenomena were less convincing than the former, because we took notice that the Feathers fell without in the least turning when the Receiver was but half exhausted. And we further noted in this Experiment, that, the Receiver being lengthened with a Cylinder of Laton, covered over with Cement, and kept from being pressed too much inward by the outward Air, by a Case made of Iron Bars, when the Air was let in again into the exhausted Receiver, it made a considerable crackling Noise, the sides of the Metalline Receiver which before were in some measure compressed being again extended. EXPERIMENT iv Of the Propagation of Sounds in the Exhausted Receiver. HAVING caused a Cylinder of Box to be turned, See Plate 2. Fig. 1. with an Axletree at each End, into the Cavity of the uppermost was received the Bottom of the Stopple; and the Axletree at the Bottom was adapted to a Hoop of Brass fixed in the middle of a Trencher, which was about 5 Inches broad, and 3 thick, and which had a piece of Led fixed to the Bottom to keep it steady; which being done, a Wire was fixed in the upper part of the Trencher, and at the End, which bent downwards, was fixed a Bell, and at another place of the same Trencher was fixed a Steel Spring, to the upper part of which a piece of Steel was joined, at such a convenient Distance, that when it was bend back by two Pegs placed at right Angles in the Cylinder (which had several Holes made in it on purpose) and the Spring on a sudden ceased to be pressed upon, it would fly forcibly upon the Bell, and give it a smart Stroak. Things being thus ordered, I caused the Receiver to be exhausted, and tho' the Sound (which was caused by turning the Cylinder fixed to the Stop-Cock, so as to make the piece of Steel strike upon the Bell) was scarce discernible, yet as Air was gradually let in, it became louder and more audible. And the like Experiment being tried by suspending a Watch which had an Alarm belonging to it, by a piece of Thread, which was tied to a Glass Button purposely blown in the inside of a Receiver which was made of one entire piece, so that it was less subject to break; we ordered the Watch so, that the Alarm should begin to go by the time that we were ready to make our Observations, at which time one that held his Ear near enough to the Top of the Receiver, perceived, that when the Air was wholly exhausted, the Sound of the Alarm was scarce at all discernible, but became much louder as the Air was gradually let in. EXPERIMENT V About the breaking of a Glass Drop in the Exhausted Receiver. TO know the Reason, why upon the Breaking of a Part of the solid Case of the Stem of a Glass Drop, which upon its first Formation falling into Water, was kept full of Rarified Air; I say, to know the Reason, why such a Bottle flies in pieces when part of the Stem is broken off upon a sudden Ingress of External Air; I caused the lower End of a Glass Drop to be fastened to a staple Body, the Stem being tied to one End of a String, and the other End being fastened to the Turn-Key; which being done, and the Receiver exhausted, the Stem was broke off by shortening the String, whereupon the Bubble flew into a Thousand Pieces, the Air enclosed expanding violently, and endeavouring to rush out at that small Vent. EXPERIMENT VI About the Production of Light in the Exhausted Receiver. TO try whether Light might be produced in the Exhausted Receiver without an Access of Air, we made use of a Virtical Cylinder, the lower Basis of which was fixed in a Staple Trencher; and having fixed two pieces of Steel in the lower End of that Cylinder, so as to rub forcibly against a Lump of Loaf-Sugar, I observed, that the Vitriol Cylinder being forcibly turned by the help of the Turning Key, the Steel made Impressions strong enough upon the Sugar, to cause it to afford, not only several Flashes, but little Sparks of fire. EXPERIMENT VII. The Production of a kind of Halo, and several Colours in the Exhausted Receiver. WE made use of a large inverted Cucurbite for a Receiver, which being exhausted, and a large Candle held on the Opposite side, when the Stop-cock was turned, to give way for the Air, to pass out of the Receiver into the Cylinder, the Cavity of the Cylinder seemed to be filled with Fumes; so that the Candle whose Flame was visible, though it appeared to be encompassed with a kind of Halo, whose Colour was between Blue and Green; and after a few Exsuctions, would be of a Reddish or Orange Colour, very vivid: Which Meteor I supposed to arise, from some Particles of the Turpentine, which extricating themselves upon the Application of a hot Iron to the Cement, caused an Explosion in the Receiver, when the Parts of the Air were put in Motion and disposed to Expansion; and the variety of Colours, I conceive to proceed from the various Positions of those Particles of Matter which fill up the Receiver and variously reflect the Rays of Light. To confirm which Opinion I observed several Steams to rise up from the Cement upon turning of the Stop-cock; and if we continued to exhaust the Receiver, it would become clearer and clearer, and the Colours more dilute, till the Cement was enabled to emit more Steams, by re-applying a hot Iron to it: And as for the Reason, why these Steams do not so plentifully rise, when the Receiver is evacuated, it appears to be, because the Particles of the Turpentine are less agitated as the Heat declines; and further, because they want Air to support them. To confirm what I have intimated, as the Causes of the aforementioned Phaenomena, I conveyed some of the Cement Melted in a Crucible into a Receiver; and observed, that upon opening of the Stop-cock to let out the Air, the Steams would for some time plentifully fly about, but after a little time would subside again. But in the aforementioned Phaenomena, the several Colours seemed to depend on the different Degrees of Heat which the Cement acquired; as also, on the different Size and Figure of the Receiver; as also, on the Nature of the Cement and the Quantity of Air which was left unpumped out. EXPERIMENT VIII. About the slacking of Quicklime in the Exhausted Receiver. HAving conveyed an Evaporating Glass, with a sufficient Quantity of Water in it into the Receiver, when the Air was drawn out, we let down a piece of unslacked Lime into it, by the Assistance of the Turning-Key; and observed, that in about ¼ part of an Hour, the Lime began to slack violently, and at each Exsuction afforded very large Bubbles, which continued as long as we plied the Pump; so that in a little time the whole inside of the Receiver was covered over with Lime Water, a great part of the Mixture boiling over into the Capacity of the Receiver; in which Experiment the Outside of the Vessel was considerably hot, and the Mixture continued its Heat near ¼ part of an Hour after the Receiver was removed: The Lime made use of in this Experiment was very strong. EXPERIMENT IX. An attempt to measure the force of the Spring of included Air, and examine a Conjecture about the difference of its strength in unequally broad-mouthed Glasses. TO measure the force of the Air's Expansion, we fixed a Syringe in a Frame, that it might be kept firm and erect; which being done, we provided a Leaden Hoop, which was suspended at the Top of the Sucker, and hung so far below the Bottom of the Syringe, that it might have Space enough to rise in upon the Expansion of the Air in the Cavity of the Syringe, when the Receiver should be exhausted; the Weight in the mean time being prevented from compressing the Air beyond its natural State by a String, the one end of which was tied to the Top of the Sucker, and the other to the Turning Key; which being done, and the Pump set on Work, we found, that the Expanding Air was able to raise about 7 or 8 pound Weight, and had the Rammer had a free Passage it probably would have raised a much greater Weight; but the Experiment was less satisfactory in determining the force of the Air's Expansion, in elevating a determinate Weight; because the Air made its way too easily betwixt the convex Superficies of the Sucker, and the concave Surface of the Cylinder. Therefore to be more exact, I caused two Cylinders to be made different both in Length and Breadth, the Diameter of the one being an Inch, and of the other two Inches; In the former, I put a Lamb's Bladder, which contained a sufficient Quantity of Air, and having ordered the Receiver to be exhausted, I found, that a Cylinder of Air of an Inch Diameter, was able to raise a Weight of 10 Pound Averdupoiz Weights; but tho' the Bladder for a long time kept the Air from flying away, yet when it was loaded with the utmost Weight it was able to bear, some Air getting out of the Bladder rendered our Trial less satisfactory. Wherefore we made use of a Cylinder 4 Inches Deep and two in Diameter, which having a broad Basis to stand upon, we put a Lamb's Bladder into it well blown and tied; See Plate 2. Fig. the 2 and 4. and putting a Wooden Plug upon that, we loaded the Plugs with Weights amounting to 35 Pound, the uppermost of which was fastened to the Turning-Key, to prevent it from falling, and then the Plug being marked at the brim of the Cylinder, we set the Pump on Work, and observed that the Expansive force of the Air in the Bladder was so great that it lifted up the Plug considerably; yet when the Air was again let into the Receiver the Plug was so far depressed that the Mark was below the Edges of the Receiver; yet the Air being again a second time exhausted, the Bladder raised the Plug so high, that ⅜ parts of the whole Plug was lifted up above the Edges of the Cylinder. And by repeating the Trial we found, that the Air in the Bladder, when the Receiver was exhausted, was able to bear up 7 pound Weight more, by which Weight the Mark upon the Plug, was not depressed below the top of the Cylinder. But in trying these Experiments the following Particulars are to be Noted. 1. That the Plug must be so adapted to the Cylinder as to move up and down easily; also it must be of a convenient length, not exceeding an Inch and a half; and it will be likewise requisite that the Plug should have a strong Ledge upon the upper part of the Cylindrical Surface, that it may rest upon the Edges of the Cylinder and sustain the Weights laid upon it more firmly. 2. When the Bladder was put into the hollow Cylinder, we took care to adapt it by easy and frequent Compressions to the Cavity it was placed in, making a Mark in the inside of the Cylinder where the Air in its Natural State was Compressed to, that we might learn what Weight the Expansion of the Air was able to sustain above that Mark; for the Air being preternaturally compressed, upon the Account of that accidental pressure may be able to raise a greater Weight than Air uncompressed, so that the Weight it raises above that Mark is alone to be taken for what Air condensed is able to lift up more than the Air in its Natural State. 3. When the Bladder was taken out of the Cylinder, the Figure of it was proportionable to the Cavity, which it was contained in, being 2 Inches Diameter, and 2 Inches and ½ long. 4. From the Experiments now mentioned it appears, that the Air is able at its first Expansion, to raise a Weight proportionably larger according to the different Boars of the Cylinders made use of; but when it hath been a little more Expanded the Proportion is not so exact, because a small Quantity of Air being to fill up ¼ or ½ part of an Inch more, the smaller Quantity of Air must be much more rarified and consequently lose of its expansive Force. But comparing the expansive Force of Air in different Boars at its first Expansion, some may think the Proportion not exact; since the small Bladder being able to raise no more but 10 Pound, and the Weight which the larger raises being 42, it is more than a Duplicate Proportionof what our Hypothesis requires; but if we consider that comparing the Diameter of each Cylinder, the Bladder in the less, proportion ably takes up more Room than in the larger; it may be sufficient to account for the Difference. 5. Considering that the Bladders in which Air is Included, may straiten the Cavities of the Cylinders, the expansive Force of the Air might be more exactly determined, could Cylinders be contrived staunch enough without such helps. 6. And it will not a little contribute to render the Force of the Air's Spring difficult to be determined, that the Air itself at different times varies, in its degrees of Pressure: Yet from what hath been said it seems probable, that were it possible to contrive an exact Cylinder very tight one, of an Inch Bore would be able to raise above 10 pound Weight. EXPERIMENT X. An easy way of making a small Quantity of Included Air raise 50 or 60 Pound or a greater Weight in the Exhausted Receiver. TO demonstrate more obviously the Air's Spring, we took a * See Plate the second Fig. 4. Brass Cylinder whose Depth was 4 Inches and its Diameter 4 Inches and ¾, to which we adapted a † See Plate short Plug, to whose upper Basis was fixed a broad Rim for Weights to stand on more firmly; which being done we pressed a Bladder into the Cylinder, that it might adapt itself to the Cavity of it; and then, observing, how much the Plug was above the surface of the Cylinder, we laid the Weights upon it (see Plate the 2d Figure the 5th) and observed that the Air in a Cylinder about 4 Inches broad lifted up 75 pound at the 5 Exsuction so high that one might discern the Mark; See Plate 2. Fig. 5. and at 2 Exsuctions more it was elevated 3/10 above the Top of the Cylinder, and at the same time, in a Mercurial Gage the Mercury that usually stood at ⅛ above the highest Glass Mark subsided to ⅛ below the Second. When the Air was let into the Receiver again, after some time the Bladder subsided again, and being taken out exactly answered the Cavity of the Cylinder. The Receiver being again exhausted at the 24th Exsuction the Mercury in the Gage was depressed to the lowest Mark, and at the 35th to ⅛ below it. And the former Experiment being tried in a small Receiver in which we heaped flat Weights one upon another, the Air raised 100 pound Weight, and would probably have raised much more, had it not been, that the Bladder was so much strained as to give way for some Air to get out at a Leak. And here it may not be improper to advertise, that the Orifices of such Receivers must not be very wide, for if they be they will be subject to be cracked by the violent external Pressure of the Atmosphere. EXPERIMENT XI. TO Compare the Gravity of Air and Water, I weighed a Glass Bubble in the Receiver, which I found to weigh above half a Grain more in the exhausted Receiver than before the Air was drawn out; and this Bubble being weighed in the open Air counterpoised 68 Grains and an half; upon which the Bubble being immersed in Water, we found that the Air in it had been so far rarified by the Heat employed in sealing it up, that the Nip being broke off, it sucked in 125 Grains of Water, the Glass together with the Water sucked into it weighing 193 ½ Grains: The whole Cavity of the Bubble being large enough to contain 739 Grains of Water, it weighing 807 ½ Grains, so that the Proportion betwixt the Weight of the Air and Water did not quite amount to 1228 to 1. Having weighed a Glass Bubble in the Receiver, whose Weight was 60 Grains, the Air contained in it in Vacuo weigh 27/92 of a Grain, and the Weight of such a Quantity of Water as it would contain, weighed 720 ¼ Grains. In which Experiment the Proportion of Air to Water in Weight was as 857 17/27 to one. But Galileo says, Water is but 400 times heavier than Water, tho' Ricciolus is as much mistaken on the other side, who says it is 10000 times heavier. To inform myself further of the Weight of the Air, I took the following Measures; having exhausted a Receiver, and when it was void of Air counterballanced it, upon turning the Stop-Cock and a Reingress of Air, it weighed 36 Grains more than before, which succeeded when tried a second time, and likewise a third. And then the Receiver being exhausted was immersed in Water, and the Stop-Cock turned to give way to an Ingress of Water, and when as much Water as was able to enter into the Receiver had succeeded in the Place of the exhausted Air, we turned the Cock again to keep that Water in, and the Receiver being again weighed, the Water weighed 47 Ounces, 3 Drachms and 6 Grains, so that the Water was heavier than its bulk of Air, near 650 Grains, the Mercury in a Baroscope at the same time being boyed up to 29 Inches ¾, so that the Weight and condensed state of the Atmosphere being greater than than usually, was the Reason why the Disproportion was not as great as at other times; tho' we may reasonably suspect, that the Quantity of Air contained in the Pores of the Water, joining with that in the Receiver, might hinder so much Water from getting in as was requisite to fill the Space deserted by the Exhausted Air; besides several Particles of Air might probably get in at the Stop-Cock, whilst the Experiment was trying, which joining with the Air remaining in the Receiver might contribute to prevent a sufficient Ingress of Water. From all which Experiments it appears, that tho' the Weight of the Atmosphere is so various, that it is impossible to know exactly the Proportion betwixt it and Water, yet it is evident that Water is to Air some Number betwixt 600 and 1100 to 1, being greater or less as the Atmosphere is more or less condensed. But these Trials are only of use in England, for the Weight of Water as well as Air, is so different in most Countries, that it is requisite to make frequent Experiments in each, to determine the Proportion of the Weight of Air in such Places. CHAP. II. A second Continuation of Physicomechanical Experiments. PLATE III. A Description of the Engine with a double Tube to exhaust the Air. A. A. TWO Brazen Pumps. B. B. Two hollow Plugs, the lower Part of whose Cylindrical Cavity is open. See Plate 3. Fig. 1. C. C. Two smaller Orifices in the upper Basis of the Plugs, furnished with Valves, which open outward, so that the Air may get out, but cannot return into the Cavity of the Plugs again. D. D. D. D. Iron Rods, fixed to the Gnomon, F. F. and designed to move the Plugs. E. E. Two Iron Stirrups fixed to the Tops of the Rods D. D. D. D. designed for the Operator to stand in, to set the Engine a going. G. G. G. A Rope which lies upon the Poultry H. each End being tied to the Stirrups E. E. L. L. Two Valves placed at the Bottom of the Pumps, so that by opening inward, they may admit the Air out of the Tube M. M. M. M. A Tube which rising from both Pumps, ends in the Plate O. O. Having first made a Curvature P. P. Q. Q. of a convenient length that the Tube P. Q. Q. may not hinder the Operator from standing in the Stirrups E. E. O. O. A Plate perforated in the Middle to afford an Intercourse betwixt the Tube P. Q. Q. and the Receiver R. To render this Engine fit for use, See Plate 3. Fig. 2. it must be supported in a Wooden Frame, (See Fig. the second;) and then a Quantity of Water being thrown into the Tube P. Q. Q. sufficient to fill the Pumps and something more, the Operator standing in the Stirrups, must weight them up and down successively, one after another, which being done, as the Plug in each Pump is raised up, the Air contained in the Receiver R. and the Tube Q. Q. will by its Spring and Expansion, lift up the Valves L. L. and make its way into the Space deserted by the Plugs in the Pumps; but as soon as the Plugs begin to be pressed down again, the Air contained in the Pumps will be hindered from passing into the Receiver by the Valves K. L. and consequently the whole Cavity of the Plugs being full of Water, the Air, as they are forced down, will lift up the Valve C. and so the Air contained in the Receiver will be successively drawn out as the Plugs move up and down alternately. The Reasons why this double Engine is preferable to a single one, is because it evacuates the Receiver more speedily, and also with less trouble; for whereas in a single one the Pillar of Air which presses against the descending Sucker is to be resisted by force, as well to depress the Sucker as to keep it from rising up again, in this double one the Weight of the Atmosphere depresses one Plug proportionably as it resists the Rising of the other, and the Motion of the Plugs up and down is rendered much more easy, when the Receiver is in some measure exhausted, because the Atmosphere which lies upon the descending Sucker helps the Operator to weigh it down, the Spring of the included Air being so far weakened as not to resist the Weight of the Atmospherical Pillar that lies upon it. PLATE IU. A description of the Mercurial Gage made use of in the following Experiment. The Gage A. B. C. D. E. is made up of three Glass Tubes cemented together, See Plate 4 Fig. 1. so that their Cavities make a continued Passage, being open to each other; The Tube B. C. D. is designedly crooked, that the lower Orifice of the Tube E. D. as well as the Orifice of Tube A. B. may be cemented to it; which being done, the crooked Tube, whose Diameter is larger than either of the other two, is to be filled with Mercury, and then the Orifice E. of the smaller Tube is to be hermetically Sealed up; but the Orifice A. of the Tube A. B. whose Diameter is larger than that of E. D. is to be left open. This Gage being put in a Receiver when it is exhausted, the Air contained in the Tube E. D. will expand so powerfully as to descend into the crooked one to C. forcing the Mercury to rise into the Tube B. A. almost to the Top, before the included Air hath lost its Spring. To discover then the Quantity of Air included in a Receiver, we may make use of the Receiver F. G. E. which being placed on the Plate L. M. we must try the Torrecellian Experiment, by inverting the Tube H. filled with Mercury into the Glass I. and then the Top of the Receiver F. being closed with Cement, and the Tube A. B. and E. D. being marked with Papers, as the Mercury in the Receiver is suspended at 30, 29, or 28 Inches or less, accordingly as the Receiver is exhausted, the same Marks, viz. 30, 29, etc. being placed upon the Papers, pasted on the Tubes of the Mercurial Gage, at each distinct Surface of the expanded Air and the rising Mercury, for the future, when the Air and Mercury descend and ascend to those Marks, in the exhausted Receiver, it will denote, that the Receiver is so far exhausted, that the remaining Air is only able to bare up a Cylinder of Mercury in the Torrecellian Experiment, so many Inches as the Mark to which the lower Surface of the Air, and the upper Surface of the Mercury rest at, is more or less in Numbers. But if the Air contained in the Receiver, be more than naturally compressed, it will likewise compress the Air contained in the Tube E. D. by squeezing the Mercury somewhat into the lower part of the Tube. How much taller a Cylinder of Mercury Air so compressed will bear up, than when it is but naturally condensed, we may learn by the following Computation. For supposing a determinate Quantity of Air to be contained in the Space A. when the Force that compresses it is F. if the Pressure F. be increased by the Pressure G. it will compress the Air contained in A. into half the space it took up before; See Fig. 2. so that the remaining Space B. will be ½ a part of the Whole: And if to the Pressure F. G. we add H. the Air which possessed the Space A. when it was only pressed by F. will be squeezed into a fourth Part of the Space A. viz. C. And consequently the Air compressed will possess a Space proportionable to the Whole, as the first Pressure is to a total Pressure. The Remaining Space: the Total Space. The First Pressure: the Total Pressure. So that three of those Quantities being known, the Rule of Proportion will teach us the fourth. For if the Atmosphere as usually condensed in England, possesses the Tube E. D. and the Atmosphere is then able to raise a Mercurial Tube of 30 Inches; When that Air is compressed into the Space N. E. to know the Quantity of its Pressure, I exactly measure the Space N. E. which if 6 Inches, I constitute that the first Term or Quantity of Pressure; so that the second Term will be the whole Space D. E. suppose 12 Inches; the third Term will be the Height of 30 Inches of Mercury, which was the first Pressure; and so the fourth Term or total Pressure will be found to be 60 Inches of Mercury; From whence I conclude, the Air so condensed in the Receiver, to be able to bear up a Mercurial Cylinder 60 Inches tall. And by the same Principle before laid down, it will be no difficult matter to judge, what the Proportion betwixt the size of the Tube A. B. and E. D. ought to be; for that depending on the Length of the Legs, the higher they are, the more able they are to restrain the Air, when it is but a little dilated in the sealed Part. For supposing the Length of A. B. to be 10 Inches, which Height of the Mercury is ⅓ of the usual Pressure; the Tube A. B. will be large enough if it be as big again as E. D. for when the Mercury hath ascended to A. the expanded Air in the other Leg possessing the Space which it forced the Mercury out of, will take up three times as much more as it did before; and consequently, ⅓ of its first Pressure will be able to curb its Spring: But if the Legs were not altogether so long, than the Mercury being but partly expelled out of the crooked Tube, the Diameter of the Tube A. B. aught to be proportionably larger in respect of E. D. That the ascending Mercury leaving it more space to expand in, it's Spring may be so far spent, that the Mercury by its Weight may seasonably resist it's further Expansion: And it would always answer, if the Height of the Gage be in the same proportion to 30 Inches, as the Space first possessed by the Air is to the Whole, which that Air would possess in Vacuo, according to the Principle above delivered. The Tube is more useful when longer, than shorter, because the expanding Air being more able to drive the Mercury into the Tube A. B. more Degrees of its Rarefaction will be discovered, tho' less sensibly. But The D. C. aught to hold Mercury enough to fill the Tube A. B. before the Air in the Tube E. D. can make its way out; But how much larger, or of what Figure it is, is not so material. A Description of the Engine made to compress Air. A. A. A Glass Vessel, See Plate 4. Fig. 3. whose Orifice is exactly covered by a Brazen Plate B. B. C. C. A Brass Tube penetrating that Plate in the middle, to which it is fixed. E. A small Valve, which opens inward, and covers the Orifice of the Tube C. E. A Spring which presses it down. G. G. G. A Gnomon fixed to the Plate B. B. to hold down the Spring F. I. I. A square Lath which the Plate B. B. lies upon, which is bored through in the Middle for the Tube C. to pass through. L. L. L. L. L. L. Two Iron Wires which being fixed in the Lath, and encompassing the Iron Plate K. K. keep it from rising too high. In the Middle of the Plate K. K. is a Screw M. M. which joins the Receiver and the Plate B. B. close together. And that the Receiver may neither be damaged by the Screw, nor the Glass by the Iron Plate, a piece of Wood and Leather is put betwixt the former, and as well to prevent damage as to render the Receiver closer, a piece of Leather is to be put upon the Plate. N. N. A Pump fixed to the Tube C. below the Plate B. B. O. O. The Sucker. P. A small Orifice at which the Air enters in, when the Sucker is brought to the Bottom of the Pump. When we have a mind to compress any thing in the Air, we convey it into the Receiver thus prepared; and drawing down the Sucker, that the Air may enter in at the Orifice P. and fill the upper part of the Cylinder, we raise the Value, by which means the Air lifts up the Sucker, and makes its way into the Receiver, till the Sucker being drawn down again, the Valve closes up the Orifice of the Pipe C. and so successively keeps the Air in the Receiver as it is forced in, the State of the pressed Air being made evident by the Mercu●…l Gage. If the Pump be fixed to the Pipe C. by a Screw, when one Receiver is full, it may be removed to another. The Mercurial Gage described in the first Figure will not so evidently show the different Degrees of the Air's Condensation as the Gage T. for the whole Tube being full of Air, except one Inch, the Condensation of so great a Quantity will be more evident. But here it will be requisite to note in very accurate Experiments, that tho' the Figure of this Gage makes it fit for short Receivers, yet if the Mercury be, when the Air is compressed, squeezed down or upwards, it's Gravity causes some difference in the Degrees of Pressure, which is not to be slighted. PLATE IU. How Mixtures may be made in compressed Air. See Fig. 3. A. A. The Receiver in which they are to be made. Q. Q. R. R. Two Tubes, the one End of each of which is sealed, and the other open. R. R. S. A Brazen Vessel laid upon the Orifice of each. The Substances to be mixed must be each put into a distinct Tube Q. Q. R. R. The Vessel of R. Q.S. being inverted, and laid upon their Orifices, and being thus conveyed into the Receiver, when the Gage T. T. shows that by the help of the Pump, the Air is sufficiently compressed, by inverting the Engine, the Substances contained in the Tubes, will be mixed together in the Vessel which was inverted on the Tops of the Tubes, when placed first in the Receiver. PLATE IU. A Description of a Wind-Gun. A. A. A hollow Copper Globe. See Fig. 4 B. B. A Tube fixed to it. F. A Valve opening internally, and shutting the Tube B. B. G. A Spring to depress that Valve. H. A Gnomon so placed as to keep the Spring-fast. C. C. An Iron Tube fixed to the Tube B. B. and the Globe A. A. D. D. A Plug adapted to the Cylindrical Cavity of that Tube. E. E. E. Another adapted to the Tube B. B. with a Wire which almost reaches to the Valve F. R. The Protuberance of the Tube C. C. whose upper Part is designedly hollow, to receive the End of the Iron L. L. L. L. A crooked Iron, whose End R. being movable, helps to lift up the Plug E. E. E. O. P. O. A crooked piece of Iron, fixed in M. that the Shoulder might be set against it when any Mark is aimed at, and that the Thumb being set against the bending P. in pressing up the Plug E. E. E. the Fingers might more vigorously draw up the Leaver L. T. T. A Rectangle of Iron, compassing the Leaver L. L. and the Iron O. P. O. to keep it in such a Posture, that the Plug may not fly out, whilst the Air is compressed into the Globe A. A. I. I. An Elliptic Hole which is shut with a Valve that opens inward; the Design of it is, that what is amiss in the Globe, may be seen and mended. S. S. A Plate of Metal perforated with a Screw V which sustains the Valve, and keeps the Hole V shut. Q. A Hole for the Air, which is to be pressed into the Globe to enter in at, when the Sucker D. is pulled down to the lower End of the Tube C. C. The Method to press Air into this Globe is this; I set my Foot upon the crooked End of the Sucker D. and then pulling up the Globe, as soon as the Tube C. C. is full of Air, I depress the Globe, by which means the Air in the Tube is forced into it through the Valve F. and this Method being taken as long as the Air's Spring would permit us to compress it any further, the Air may be discharged, if, when the Plug D. is drawn out, and a Bullet is put into the Tube instead of it, the Plug E. E. E. be raised so that the End of the Iron Wire may open the Valve B. for the Air violently rushing out, will drive the Bullet away with great Violence. The Globe will be sooner filled with Air, if half an Ounce of Water be put into the Tube C. C. before the Sucker D. for the Top of the Tube being filled with Water, the Air will be forced clearly out of the Tube into the Globe. And this Wind-Gun hath these Advantages above any other yet mentioned; First, that it is not so subject to be spoiled, as those that have two Valves; Secondly, it is easily mended, what is amiss being taken out at the Elliptic Hole. Thirdly, it is much more staunch, the Crannies being stopped with Silver Soder, which damages not the Leather on the Valve, because it is put in after the Soder is cooled, at the Elliptic Hole. Fourthly, several Bodies may be conveyed into it at the Elliptic Hole, whereby we may be enabled to try several Experiments. PLATE V How Factitious Air may pass out of one Receiver into another. A.A. A Metalline Plate perforated in the Middle. B. B. To which a Stop-Cock is fixed, the lower Orifice being made into a Male Screw. D. C. Which is received by the Female Screw D. of the Copper Funnel D. C. See Fig. 2. E. E. A hollow Tube, both of whose Ends are form into a Female Screw, to receive the Male Screw of the Stop-Cock B.B. See Fig. 1. F. F. The Receiver laid on the Plate A. A. and exactly fitted to it. The Matter of which factitious Air is to be made, is to be put into the Receiver F. F. and the Orifice of the Tunnel C. being placed on the Receiver, and the Stop-Cock B. being opened, the Air is to be drawn out of the Receiver, which being done, the Stop-Cock is to be shut again, and the Male Screw being taken out of the Female Screw in the Brass Tunnel, the Receiver is to be immersed in Water to keep External Air out; As for the Degrees of Compression of the factitious Air, they may be discovered by the Mercurial Gage before mentioned. To transmit this Air into another Receiver F. F. we make use of the small Tube E. E. Fig. the Second, into each End of which the Stop-Cocks of two Receivers being screwed, and the Crannies stopped with Cement, by turning the Stop-Cocks, the Air may be let out of one into the other. To discover the Rarefaction of the Air contained in which Receivers, because they must be inverted, we contrived the following Gage. See Fig. 4. A. A. A Viol filled with Mercury up to the Superficies D. D. B. B. A Tube cemented in the Neck of it. C. C. Another which passing through the Tube B. B. leaves room for a due intercourse betwixt the External and Internal Air, the upper End of which must be sealed, and the other End open. If this Gage be put into a Receiver when it is inverted, both the Tubes will have the Air contained in them exhausted, and will be ready to receive factitious Air, as soon as the Stop-Cocks are turned to give an Intercourse betwixt them; and then the Gage being inverted, and the Mercury which lay below the Orifice of the Tube B. B. falling about the Pipe C. C. by rising up into it, will show the Degrees of the Compression of that factitious Air. PLATE VI An Instrument by which Air may be filtrated through Water. See Fig. 1. A. A. A Glass Receiver whose Orifice is adapted to the Plate B. B. which is perforated in the Middle by the Tubes C. C. D. D. which are cemented to it. E. E. E. E. A Stop-Cock into which the lower Ends of the Tubes C. C. D. D. are inserted. F. F. The Key of the Stop-Cock in which is made the Chink G. G. without any Perforation. H. H. The Receiver to which the Stop-Cock is fixed, preventing an Ingress of outward Air, and having a due Intercourse with the Pump I I L. L. A Glass Vessel. M. The Stopple in the Top of the Receiver fastened with a Screw. See Fig. 2. A Stop-Cock cut transverse, so that the Insertions of the Tubes C. C. D. D. into the Stop-Cocks may be perceived. The Use of this Instrument is as follows, To try how much Air may acquire new Qualities in respect of a Body included with it, we convey that Body into the Vessel, and then pouring a sufficient Quantity of Water at the Orifice M. until the Receiver A. A. be half full, and the Vessel L. L. swim up to the Top of it, the Orifice M. is stopped up, which being done, and the Key so placed, that the Tube C. C. may communicate with the Chink G. G. upon drawing down the Sucker, the Air in the Receiver A. A. will pass through the Pipes C. C. and the Chink G. G. into the Receiver H. H. and from thence into the Pump: Upon which, the Chink in the Stop-Cock being turned so as to communicate with the Insertions of the Tube D. D. and then the Sucker being raised to the Top of the Cylinder, the Air will be impelled into the Tube D. D. and emerging through the Water, will rise into the Top of the Receiver A. A. and by this Method we could strain it through Water as often as we had a mind to be informed, what new Qualities it acquired in reference to the Bodies about it. FIGURE III. How the same Numerical Air may be sometimes condensed, and sometimes rarified. The Receiver A. A. being fixed upon the Plate B. B. and the Stop-Cock C. C. being fixed to the Perforation of the Plate B. B. The Pump D. D. is joined by a Screw to the Stop-Cock C. E. A Vessel which fluctuates in the Receiver, in which an Animal being put, and the Pump filled with Water, and joined to the Stop-Cock by a Screw, the Water contained in the Pump will, by lifting up the Sucker, be forced into the Receiver, and by that means condense the Air, without an addition of new, and by drawing the Sucker down again, the same parcel of Air will be again expanded; so that Observations may be made, how much the thickness or thinness of Air contributes to the preservation of the life or health of Animals. PLATE VII. An Instrument to distil in Vacuo, See Fig A. A. A Brazen Vessel, the lower part of which is shut, and the upper open. B. B. A piece of Tin tightly adapted to the Tube, so as to prevent the External Air from entering in, being adapted to the Edges of it A. A. D. D. C. C. A Tube fixed in the middle of the Tin Plate B. B. D. D. A Brazen Vessel, whose Orifice is contiguous to B. B. E. E. A Stop-Cock fixed to the Perforation in the Plate B. B. F. F. A Tube-reaching from the Stop-Cock to the Pneumatick Engin. G. G. A metalline Vessel enclosing the Junctures of the Vessels with the Diaphragma, and also the Stop-Cock, that by keeping them immersed in Water, they may be free from External Air; this is cemented to the Vessel A. with Soder. The manner of using this Engine is the following, viz. The Tin Plate being removed, and the Ingredients to be boiled, being put into the Vessel A. A. then re-applying the Tin Plate A. A. and the Vessel D. D. and the Tube F. F. being applied to the Pneumatick Engine, and the Air pumped out, the Vessel G. G. having been first filled with Water, we shut the Stop-Cock, and remove the Tube F. F. and then the exhausted Vessel being placed on the Fire, Vapours will ascend through the Tube C. C. which will be condensed in the upper Vessel; and what Quantity of Air is there generated, will appear by the Mercurial Gage H. in the Top of the Vessel. But here it is to be noted, that round pieces of perforated Paper being laid upon the Orifices of the Vessels A. A. D. D. they will be more exactly joined with the Tin Plate. The Junctures of the Tube F. F. both with the Pneumatick Engine and Stop-Cock are to be guarded with Cement, and the Stop-Cock must be so contrived, as to stand so far without the Vessel G. that it may be conveniently turned: When any thing is to be conveyed into the Vessel, the Tin Plate E. E. and the Stop-Cock may be laid aside: Which may be done without any great Dissiculty; for the Key being made up of two parts, the one of which M. is turned in the Stop-Cock, by a Chink, into which the End of the other part O. O. which fills the Pipe N. N. fixed to the Vessel G. G. is received, so that one End being prominent outwardly, whilst it is turned, it may communicate Motion to the other Part M. But whilst the Tin Plate B. B. is is to be taken out of the Vessel G. G. it must be drawn outward. Fig. 2. Another Instrument for the same Use with the former. B. B. A small Tube, both Ends of which are polished, that it may be exactly adapted to the Orifices of the Vessels A. and D. A. A. D. D. Two Vessels made of Glass, so joined by the Tube B. B. that Vapours may pass from one to the other. E. E. F. F. G. G. I. Are of the same Use with the first Figure, and the Instrument is to be evacuated by the same Method; only the Glass Vessel must be placed in Balneo Mariae, or on Sand, and the Vapours so raised will condense in the Vessel D. D. CHAP. III. ARTICLE. I. Several Ways to help the Production of the Air. EXPERIMENT I. Air produced from Bread. TO try whether a piece of Bread, which was moist, and a little kneaded, would yield Air; I included it in Vacuo with a Mercurial Gage, July 12th 76. but it yielded none: On the 12th. some broke in the Receiver, and raised Mercury 3 Inches high; and at Night it was raised an Inch higher, tho' no external Air got in. July 13th. it ascended higher. On the 26th Day it expanded itself so powerfully, as to separate the Receiver and its Cover, the Smell of it being acid. So that Air may be drawn out of Bread by such a Menstruum as Water. EXPERIMENT II. JVly the 11th. Bread being burnt by a Burning-Glass in Vacuo, yielded Air, which came from it with an Explosion; whence we may guests, that could Air be separated more easily from it, it would produce very considerable Effects. EXPERIMENT III. Septemb. 22. I Enclosed in a Receiver, From Grapes. Eight Ounces of dried Grapes, bruised in 7 Ounces of Water, the Receiver being large enough to contain 22 Ounces. Septemb. 23. Tho' the Receiver was covered with Water all Night, the Mercury was raised two Inches. Septemb. 30. In seven Days it was raised thirteen Inches. Octob. 5. In five Days more it was 25 Inches high. Octob. 18. The Mercury ascended slowly, some Air making its way out of the Receiver. Grapes without Water did not yield Air so plentifully. See Art. IX. Exp. I. EXPERIMENT IU. July 12. I Shut up 10 Ounces of Raisins of the Sun bruised, From Raisins. in as much Water as was sufficient to make them ferment. July 14. In 48 Hours raised the Mercury ten Inches; at Night the Mercury was 5 Inches higher; the next Day it was almost as high as when buoyed up by the Atmosphere. July 16. In the Morning the Receiver and its Cover were separated by Air, which got through the Water which the Receiver was covered with. The same Raisins were shut up in Vacuo again. July 18. In the Morning the Air broke out. July 19 They were enclosed in the empty Receiver. July 21. The Receiver was so full of Air, that some of it forced its way out; and they were enclosed in the exhausted Receiver again. July 22. The Receiver was almost full: The 23d in the Morning it forced itself out. When the Parts of the Water have worked upon Grapes 5 or 6 days, they yield. Air very fast, tho' at the first they do not. EXPERIMENT V. August 13. 1677. PLums were shut up in one Receiver, From Plums. and Pears in two others. August 16. They were all full of Air, and one which contained Pears, and lay open to the Sunbeams, raised the Cover in 24 hours. EXPERIMENT VI. Octob. 16. 77. From bsed Grs. I Enclosed two Ounces of bruised Grapes in a Receiver large enough to hold 20 Ounces of Water .. Octob. 17. The Mercury was raised half an Inch. Octob. 18. The Mercurial Cylinder was raised half an Inch more. The 20th it increased 2 Inches. The 22d 4 Inches. The 27th near 6 Inches. Jan. 2. 78. It was not quite 10 Inches high. Octob. 16. 77. Three Ounces of bruised Grapes being included in an exhausted Receiver, large enough to contain 30 Ounces of Water, with half an Ounce of Spirit of Wine. Octob. 17. The Mercury did not ascend much. Octob. 18. It was not an Inch high. Jan. 2. 18. The Receiver was quite full, and some of the Liquor as it was poured out, produced Bubbles in some Turpentine about the Orifice, which broke outwardly. Tho' Spirit of Wine promotes the Generation of Air in Vacuo, yet in the open Air it hinders it. See the II. VIII. and XIV. Exp. Art. II. EXPERIMENT VII. July 19 78. MU expressed; From Must. bruised Grapes were put into a Receiver, when it was 10 Months old. The 21. The Mercury was no higher. 23. It was raised 3 Inches. 24. Raised 5 Inches. 25. In the Morning it was 104, in the Evening 137 and the Must made its way out. 26. More Must got out. The Air was further expanded, but the Mercury was suspended at the same height. 27. The Screw being left open, half the Must got out: From thence it appears, that by keeping Grapes for some time, their Fermentative Virtue becomes more powerful. EXPERIMENT VIII. Jan. 30. BOiled Apples being put into Receivers, From boiled Apples. with, and without Sugar, they both presently filled them full of Air. Jan. 31. Raw Apples being shut up in Receivers, in one of which was put a third part of Sugar, and the other without. Feb. 10. The former had yielded some Air. Feb. 14. The raw Apples and Sugar raised the Mercury 30 Inches: Those which were boiled raised it two Inches: In the other Receivers we had no Air generated, Feb. 18. In the Receiver in which the raw Apples and Sugar were enclosed, the Mercury was raised 56 Inches. The Boiled Apples and Sugar raised it 3. The raw Apples had yielded little; but in that which was almost full, the Apples were very little Fermented, but of a very pleasant Taste. Feb. 21. The Cover was broke, and the Apples and Sugar had lost some of their Juice, but they were not Rotten. March 1. In the great Receiver in which raw Apples were shut up, the Mercury was raised 25 Inches: In the little One not above 7. Where Boiled Apples and Sugar were contained it was raised 9 Inches. March 8. In the large one it was 29. In the less 22 ½. That where the Boiled Apples were, stayed at 9 Inches. March 17. Some Juice got out of the large Receiver: In the less the Mercury stood at 67 Inches; and the boiled Apples and Sugar raised it 15 Inches. From whence it appears, that the Sugar, and the largeness of the Receiver as well as the Crudity of the Fruit contributed to the Production of Air. ARTICLE II. Several ways to hinder the Production of Air. EXPERIMENT I. Decemb. 20. 78. DOugh made without Leaven; From Dough. but with the same Meal with Breadcorn, being enclosed in a Receiver, where the Heat of a Fire kept it warmer than at Midsummer, in 10 hours it yielded no Air: So that if Doughty be once too cold it hinders its Fermentation for the future, which I the rather believe, because Doughty being shut up in the Summer presently generated Air. EXPERIMENT II. May 23. THree Ounce of Doughty Leavened being enclosed in a Receiver large enough to hold 50 Ounces of Water; I put Spirit of Wine to it. May 24. The Mercury was Three Inches high. May 26. The change was small. May 27. None at all. May 29. None at all. June 2. It ascended a little. June 14. Not at all. Decemb. 14. Being taken out it smelled subacid: And being put into an Empty Receiver it swelled so much as to take up twice as much space as before with a gentle Ebullition. May 23. The same Quantity being of Doughty shut up without Spirit of Wine. May 24. The Mercury was 19 ½ Inches high. May 26. It's Height was 38. May 27. No alteration. Decemb. 14. It continued at the same Height; and the Dough smelled subacid: From whence it appears, that Spirit of Wine prevented the Generation of it in the last Experiment. EXPERIMENT III. August 29. PEars, From Pears. and a Mercurial Gage being closed up in a Receiver filled with Water, such a Quantity of Air was pressed in as was able to raise the Mercury 26 Inches higher than it used to be. In a little time they were all made like a Pultis for Consistence. Aug. 30. In 24 hours the Mercury was depressed an Inch and an half. Aug. 31. It remained at the same Height. Sept. 1. They began to yield Air, the Mercury being raised to 27 Inches. Sept. 2. In 24 hours it was raised 8 Inches higher. Sept. 3. The Height of the Mercury was 17 Digits higher, the height being 52 Inches. Sept. 4. The Mercury was buoyed up 7 Inches further, rested at 59 Inches. Sept. 5. The height of the Mercurial Tube was 64 Inches: And a Pear broken in the Receiver was turned Black. Sept. 6. It was raised 3 Digits and ¼ higher than what is usual. Sept. 7. It was 3 Digits lower, and rested again at 64 Inches. Sept. 8. This day the Mercury subsided to 58 Inches. Sept. 9 It was raised up 3 Digits higher again, and was suspended at 67 Digits. Sept. 10. In 24 hours it was raised 1 ½ higher, being suspended at 69 Inches. Sept. 11. It descended to 67 Digits again, the Night being very cold. Sept. 12. No Alteration happened at all. Sept. 13. It subsided further to 64 Digits, the Cold was sharper. Sept. 14. It was 70 Digits high. Sept. 16. It subsided to 69. Sept. 19 It stood at the same height. Sept. 20. It was raised again to 71. Sept. 23. It subsided to 69. Octob. 1. It was buoyed up again to 75 Digits. Octob. 3. On the 2 there was no alteration: To Day it stood at 70, the Wether being exceeding cold. Octob. Yesterday the Mercury remained at the same height; but this Day being Rainy it risen again to 75. Octob. 7. The Wether being the same, the Mercury was at a stand. Octob. 10. This Day it subsided to 69 Inches, the Rainy Weather continuing. Octob. 12. To Day it was Depressed to 65 Inches: Cold Wether coming on again. Octob. 13. It was 64 Inches high. Octob. 14 It was 69 Digits high. Octob. 15 It was 74 Digits high. Octob. 24 It was 68 Inches. The Season being cold Nou. 2. It was 64. The Cold more violent. Nou. 5. The Mercury was 80 ½ Inches high. The Cold more moderate. Nou. 2. It was 65 Inches high: It was sharp frosty Wether. Nou. 27. It was 68 Inches high. A Thaw coming on. Dec. 6. It was 61 Inches high. The Wether being very Frosty. From the former Experiment, it appears, that Fruits yield not Air plentifully when violently compressed, in the Air: The Air afforded, when they are compressed not being ⅛ of what they yield in the Empty Receiver. But that the Cold might concur to hinder the Generation of Air will be evident from the following Experiment. EXPERIMENT IU. Feb. 22. 77. TEN Ounces of Paste being included in a Receiver which was large enough to hold 22 Ounces of Water, From Paste. I impressed Air enough into it to sustain 73 Inches of Mercury above the length of a Cylinder which the Weight of the Atmosphere is able to bear up. In two hours there was no sensible Alteration. Feb. 23. In 18 hours the Mercury was raised 7 Inches. And in 6 hours more it ascended 8 Inches higher, being buoyed up to 83 Inches. Feb. 24 It was 90 Inches high. Feb. 25 It was 97 Inches high. Feb. 26 It was 101 Inches high. Feb. 27 It was 105 Inches high. Feb. 28 It was 107 ½ Inches high. March. 1 It was 112 Inches high. Water seemed to be expressed out of the Paste. March. 2 It was raised to 120 Inches. March. 3 It was raised to 121 Inches. March. 4 & 5 It remained at 121 Inches. March 8. Upon a Thaw the Mercury ascended 4 Inches and rested at 125 Digits. March 10. It risen 6 Digits higher, being suspended at 131 Digits. March 21. The Season being so long Cold, no Air was generated, except that in the three last Days the Mercury was raised 7 Inches, and rested at 138 Digits. April 4. One of the Iron Wires made use of to straiten the Receiver, was broke, and the sides of the Receiver started out of their Places 4 or 5 Foot. From whence it appears that Cold and Compression hinder the Generation of Air. EXPERIMENT V. March 1. 77. TWO Raisins of the Sun being bruised were shut up in an exhausted Receiver with Six Ounces of Vinegar: It afforded Bubbles plentifully. March 2. It still yielded Bubbles; but the Mercury was not raised half an Inch. March 25. The Vinegar seemed to contain Bubbles; but the Mercury was not raised an Inch. So that Vinegar hinders Fermentation and the Production of Air. EXPERIMENT VI. April 7. HAving put 10 Ounces of Paste into a Receiver able to contain 22 Ounces, Paste included in a Receiver. of Water, as much Air was pressed in as sustained Mercury above its usual height 128 Inches. In Six hours it was raised four Inches, being sustained at 132 Digits. April 8. In 16 hours it ascended 9 Inches higher, but for nine hours after it rested at 141. April 9 Some Air broke out in the Morning; the Mercury subsided to 130 Inches, therefore thrusting in as much Air as raised it to 141 I closed it it up with a Screw. Apr. 10 It was at 151 Digits. Apr. 11 It was at 158 Digits. Apr. 12 It was at 168 Digits. Apr. 13 It was at 176 Digits. April 14 It was at 183 Digits. April 15 It was at 183 Digits. April 16 It was at 187 Digits. April 17 It was at 191 Digits. April 27. Eight Days its Station was unalter'd, but the two last it was raised 7 Inches, being raised to 198 Digits. April 30. So much Air being let out, that the Mercury was raised but 50 Inches above its usual height, to try whether the compressed State of that Air hindered it from expanding, the remaining Air being pinned up presently raised the Mercury sensibly, and 3 hours after the Mercury was raised to 62 Digits from 50. In five hours' space after rose 1 ½. May 1. In 15 hours it raised only an Inch. May 3. On the Second it was at a stand; to Day it was raised 1 ½. May 4. The Mercury ascending no higher, I let the Air go; and the Screw being set again, in five Minutes the Mercury was raised two Inches. May 7. In 3 Days it was raised 2 Inches higher. May 8. In the two last Days it was raised ½ an Inch. And the mass being shut up in Vacuo, in 5 hours the Mercury was buoyed up an Inch. May 21. It had not been raised 3 Inches yet. May 30. It rested at 4 Inches and ½. From whence it appears, that all the Air that Paste will afford, may be obtained from it, tho' it be compressed; yet it is hindered in some Measure, till that Pressure is taken off. And from hence it appears, that Air may be generated by repeated Turns and Reciprocations; and that it is more slowly generated in compressed, than in free Air, it usually yielding all that it will, in two or three Days time. EXPERIMENT VIII. Artificial Air. July 30. 77. HAving included Plums and Apricocks cut asunder in a Receiver, Plums and Apricocks. I pressed so much Artificial Air of Cherries into them, as raised 64 Digits of Mercury. August 1. They yielded no Air, but became Yellow, as if too ripe. August 3. The Mercury was raised a little higher, and a whole Apricock, appeared full of Drops of Water. August 7. The whole Apricock grew softer; and the Mercurial Cylinder 59 Inches taller than its usual Length. August 8 It was 61 Digits high. August 9 It was 65 Digits high. August 10 It was 71 Digits high. August 11 It was 74 Digits high. April13 It was 78 Digits high. April14 It was 80 Digits high. April15 It was 80 Digits high. April16 And till the 22 th' it rested at the same height. The 24th it was 77 Inches high. On the 29th I opened the Receiver, and found that the Fruit was well Coloured and smelled Sub-acid, the Flesh being Spongeous; It emitted several Bubbles when first it was freed from the ambient Pressure. Common Air. July 30. 77. The same Fruit being conveyed into a Receiver with Common Air, some being cut and others whole. July 31. The Mercury was raised 8 Inches high. August 1. At six a Clock in the Evening the Mercury was raised 20 Inches. August 3. The Fruit was much more firm, than those Included with Artificial Air. The Mercury was raised to 35 Inches. August 4. The Mercurial Cylinder was raised to 42 Inches. August 6. The Apricock appeared unalter'd: The Mercury stood at 57 Inches. Aug. 7 It was 81 Digits high. Aug. 8 It was 95 Digits high. Aug. 9 It was 113 Digits high. Aug. 10 It was 124 Digits high. The Apricock began to turn Yellow: But did not in the least appear Moist. Aug. 11 It was 131 Digits high. Aug. 13 It was 157 Digits high. Aug. 14 It was 163 Digits high. Aug. 15 It was 171 Digits high. Aug. 16 It was 171 Digits high. Aug. 17 And for some time after it stood at the same height. Aug. 27 It was 182 Inches high. Aug. 29 The Receiver being opened, the Apricocks were more Acid and less grateful to the Taste, than those in factitious Air: The Pulp was well Coloured, but Spongy; they yielded Bubbles as the others did. From this Experiment, we may be induced to think that the Artificial Air, hindered the Apricock enclosed with them, from yielding Air; yet it enriches their Colour and Firmness; and is good to preserve their Taste. EXPERIMENT VIII. Grapes without Spirit of Wine. AN Ounce and an half of unripe Grapes bruised being enclosed in a Receiver, capable of holding 10 Ounces of Water. Oct. 11 The Ascent of the Mercury was small Oct. 12 The Ascent of the Mercury was small Oct. 13 It was ½ an Inch. Oct. 17 It was 1 Inch. Oct. 18 It was 1 ½. Oct. 19 Near 4 Inches. Oct. 20 The same, but their surfaces seemed mouldy. Oct. 21 It was 4 ½. Oct. 22 The same, the surface seemed more mouldy. Oct. 23 The same, the surface seemed more mouldy. Oct. 24 The same, the surface seemed more mouldy. Octob. 26 It was 5 ½ Inches high. Octob. 27 It was 6 Inches high. Octob. 28 It was 6 ½ Inches high. No. 2 It was 7 ½ Inches high. No. 6 It was 9 Inches high. No. 8 It was 10 Inches high. No. 9 It was 13 Inches high. No. 12 It was 15 Inches high. No. 14 It was 17 Inches high. No. 18 It was 23 Inches high. No. 21 It was 26 Inches high. Dec. 8 It was 36 ½ Inches high. Dec. 12 It was 39 Inches high. Dec. 27 It was 39 Inches high. Jan. 6 It was 36 Inches high. The Air made its way out. Octob. 10. 677. Grapes with Spirit of Wine. The Experiment being made with another Receiver into which was put 2 Drachms of Spirit of Wine along with the Grapes. Oct. 11 The Mercury unalter'd. Oct. 12 The Mercury unalter'd. Oct. 13 The Mercury unalter'd. Oct. 17 The Ascent was small. Oct. 18 Not ¼ of an Inch. Oct. 19 It risen but little. Jan. 6. The Grapes all this time afforded no Air: So that Spirit of Wine hindered their Fermentation. EXPERIMENT IX. HAving conveyed a Peach into a small Receiver, and so much Spirit of Wine as was just able to afford Vapours to rise about it. March 28. 78. It had the same Colour but was the less Firm: It had almost wholly contracted the Taste of the Spirit of Wine, but yielded not Air. EXPERIMENT X. Air with Spirit of Wine. I Conveyed 5 Peaches into a Receiver with as much Spirit of Wine as was sufficient to raise Vapours about them. Octob. 18 The Mercury ascended not. Octob. 20 It was 3 ½ Inches. Octob. 21 It was 5 ½ Inches high. Octob. 22 It was 7 ½ Inches high. Octob. 23 It was 9 Inches high. Octob. 26 It was 9 ½ Inches high. Nou. 2 It was 12 Inches high. Nou. 6 It was 14 Digits. Nou. 12 It was 16 Digits. Nou. 14 The same. Nou. 16 The same. Dec. 8 It was 18. Dec. 16 It was 19 ½. Dec. 27 It was 20 ½. Jan. 6 It was 23. March. 8 It was 31 ½. Air without Spirit of Wine. Octob. 17. Five Peaches being shut up in a Common Receiver without Spirit of Wine; Octob. 18 it ascended not. Octob. the 20th The Mercury was 5 Digits. Octob. 21 It was 8 Octob. 22 It was 10 Octob. 23 It was 10 Octob. 26 It was 12 Nou. 2 It was 15 Nou. 6 It was 17 ½ Nou. 12 It was 20 Digits high. Nou. 14 It was 20 Digits high. Nou. 16 It was 21 Digits high. Dec. 8 It was 26 Digits high. Dec. 16 It was 26 ½ Digits high. Dec. 27 It was 28 ½ Digits high. Jan. 6. 78 It was 32 Inches high. March 28 It was 33 ½. April 15. Liquor broke out, and the Air after it: From this Experiment it appears that the Vapours do not hinder Fermentation so much as Spirit of Wine itself. EXPERIMENT XI. Paste with Leaven. HAving closed an Ounce and a half of leavened Dough in a Receiver with so much Air as was able to bear up 23 Ounces ½ of Water. April 28. The Mercury in the Gage was 2 ½ of an Inch high. April 3. It was 3 ¼ of an Inch high. May 4. The Mercury subsided, and the Paste was Mouldy, It was raised 2 ½ high. May 6 It was 2 ¾ May 8 It was 3 May 10 It was 3 ½ May 14 It was 4 May 17 It was 4 ½ May 20 It was 5 May 24 It was 6 May 28 It was 8 June 2 It was 9 June 6 It was 10 June 41 It was 11 ½ July 5 It was 13 ½ July 19 It was 15 Paste without Leaven. April 27. 78. An Ounce and a half of Paste without Leaven being contained in a Receiver large enough to hold 23 Ounces ½ of Water. Without Leaven. April 29. In the Afternoon it ascended ¼ of an Inch. April 30. There was no Alteration. May 4. It ascended slowly and the Paste turned Mouldy. May 6. It was about 4 Inches high. May 8 It was 5 ½ May 10 It was 7 ½ May 14 It was 10 ½ May 17 It was 12 ½ May 20 It was 13 ½ May 24 It was 16 ½ May 28 It was 18 ½ June 2 It was 20 ½ June 6 It was 21 ½ June 14 It was 25 ½ From whence it appears, that Leaven hinders Fermentation and the Production of Air. EXPERIMENT XII. May 23. Paste with Spirit of Wine. AN Ounce and a half of Paste, on which Spirit of Wine was poured, being shut up in a Receiver. May 24th The Height of the Mercury was 1 Inch. May 26 It was near 2. May 27 It was near 2 ½. May 31 No Alteration. June 1 It was 3 ½ Digits high. June 6 It was 4 Digits high. June 10 It was 4 ½ Digits high. July 19 No Variation. Decemb. 14. The Receiver being opened, the Paste smelled subacid. Paste without Spirit of Wine. May 23. Without it. An Ounce and a half of Paste being put into a Receiver large enough to contain 25 Ounces of Water, without an Addition of Spirit of Wine. May 24. The Mercury did not ascend. May 26 It was 3 Digits high. May 27 It was 4 ½ Digits high. May 28 It was 5 ½ Digits high. May 29 It was 7 Digits high. May 31 It was 9 ½ Digits high. June 2 It was 12 Digits high. June 6 It was 17 Digits high. June 10 It was 22 Digits high. July 4 It was 30 Digits high. July 19 It was about the height of 30 Digits. The Air broke out. Decemb. 14. The Mercury was raised 15 Digits again; The Receiver being opened, the Paste was very acid. From these Experiments it appears, that Spirit of Wine prejudices the Production of Air; And it likewise hence is evident, that Paste which is made without Ferment, will in time yield as much Air, as that prepared with it. EXPERIMENT XIII. Octob. 11. New Ale enclosed in a Receiver. NEW Ale was put into one Receiver, so that the whole Cavity was taken up with it, and another Receiver was likewise filled with the same Liquor, except a small Part of its Cavity which contained Air. Octob. 12. In the Receiver exactly filled, the Mercury was raised a little; the other had its Cover burst, and the Ale was conveyed into another large enough for the Purpose. Octob. 13. In that wholly filled, the Mercury was 12 Digits high; In the other it was raised 13 Digits. Octob. 14. The Mercury in the full Receiver was 13 Inches, and the other 18. In the Evening the height of the Mercury in the full Receiver was 22 Inches, and in the other 20. Octob. 15. The Height of the Mercury in the full Receiver was 42 Inches: In the other 26. The Bubbles which before appeared in the full Receiver disappeared; And the Air in the Gage possessed a larger Space than before. In the full Receiver the Height of the Mercury was Octob. 16 60 Inches. Octob. 18 90 Inches. Octob. 22 90 Inches. Octob. 23 108 Inches. Octob. 26 108 Inches. Octob. 28 138 Inches. In the other. Octob. 16 30 Inches. Octob. 18 40 Inches. Octob. 22 42 Inches. Octob. 23 50 Inches. Octob. 26 60 Inches. Octob. 28 63 Inches. The Bubbles appeared again. Nevemb. 8. When the Receiver was opened the Ale seemed ready to fly into Froth, except the Orifice was presently stopped again; It's Taste was very Pungent: As the Hole in the Gage is opened or shut, the Mercury will descend or ascend. Novemb. 9 Almost the same Phaenomena were taken notice of when the other Receiver was opened. From this Experiment it appeared, that tho' the Ale sooner ferments when Air is permitted to be with it, than when it is not; yet the Ale in such Receivers, at the last expands more violently. EXPERIMENT XIV. June 27. Pease with Spirit of Wine. GReen Pease and Spirit of Wine being put into the Receiver, by some Air that got in accidentally, the Mercury was raised 18 Inches: to prevent which a second time, the Receiver was cemented, and made firm with Turpentine. June 30. The Height of the Mercury did not vary. July 7. No Air was generated in the highest Degree of Heat. Pease without Spirit of Wine. The same Quantity of Pease being put into the Receiver, as in the last Experiment, without Spirit of Wine. June 28. At night the Height of the Mercury was 5 Inches. Jun. 29 It was 10 Digits high. Jun. 30 It was 16 Digits high. July 1 It was 19 Digits high. July 5 It was 26 Digits high. July 7 It was 30 Digits high. July 8. The Air got out of the Receiver, it being too much filled. From which it appears, that Spirit of Wine hinders the Generation of Air in Pease. ARTICLE III. The Effects of Artificial Air, are different from the Effects of common Air. EXPERIMENT I. June 19 77. Cherries in: closed in a Receiver. CHERRIES being shut up in an evacuated Receiver; the Mercury was raised in 6 hours 5 Inches ½. June 20. The Mercury was raised 3 ½. At night it was 2. June 21 It was raised 1 ½ June 22 It was raised 1 ½ June 23 It was raised 2 June 24 It was raised 1 ½ June 25 It was raised 1 ½ June 26 It was 3 June 27 It was 3 June 28 It was 5 June 30 It was 1 ½ July 1 It was raised 3 July 2 It was raised 4 July 3 It was raised 2 July 4 It was raised 2 ½ July 5 It was raised 3 It was 45 Inches high, but the Air being conveyed into another Receiver, It subsided to 25 Inches. July 6 It risen 4 July 7 It risen 5 ½ July 8 It risen 5 July 9 It risen 5 July 10 It risen 6 July 11 It risen 12 July 13 It risen 7. July 13. The Mercury being raised 3 Inches, was suspended at 92 Inches, and the Air being conveyed into another Receiver, was 50 Inches high. July 14 It was raised 14 July 15 It was raised 11 July 16 It was raised 13 July 17 It was raised 5 July 18 It was raised 9 The 19 It was subsided from 102 to 92 Inches; Part of it being conveyed into another Receiver. The 20 It ascended 15. The 22 Air getting out, it subsided to 63 Inches ½ The 23 It ascended to 12 ½. The 24 It ascended 4, the height of the Cylinder being 79 But the Air being removed into another Receiver it stood at 62. July 25 It risen 8 July 26 It risen 9 July 27 It risen 4 July 28 It risen 5 July 30 It ascended ten Inch. the Length of the suspended Cylinder being 98 Inches. And part of the Air being conveyed into another Receiver, it stood at 64. July 31 It risen 6 Inc. August 1 It risen 9 Inc. August 2 It risen 4 Inc. August 3 It being removed into another Receiver was 68 Inches high. August 4 It being removed, subsided to 54 Inches. August 6 It risen 7 In. August 7 It risen 4 In. August 8 It risen 0 In. August 9 It risen 3 In. The Receiver being opened; the Cherries were almost insipid, being of a whitish Colour, and the Pulp spongy. From this Experiment it appears, that, tho' Cherries are capable of yielding Air, yet the Production of it is not very regular. EXPERIMENT II. July 13th 67. Cherries enclosed in a Receiver. CHerries being enclosed in a Receiver, together with as much Air, obtained from Cherries put up in another Receiver, as was able to sustain a mercurial Cylinder 50 Inches. July 15. It was raised two Inches higher, tho' the day before there was no Variation in its Height. July 16 It was raised 1 ½ July 17 It was raised 1 ½ July 26 It was raised 18 Some Air got out. July 27 It was raised 2 Some Air got out. July 30 It was raised 7 July 31 It was raised 9 Inches. August 1st. It stopped at the height of 61 Inches, some Air making its way out. Aug. 27. The Air being wholly vanished; I took out the Cherries, which retained their Colour without Putrefaction: Their Taste was acid, and the Pulp was full of Cavities like fermented Paste. From this and the foregoing Experiment compared, it appears that Fruits yield less in artificial than common Air, and consequently, their natural State is longer preserved. EXPERIMENT III. Septemb. 10th 77. Common Air. Grapes enclosed in a Receiver. SIX Ounces of unripe Grapes being shut up in a Receiver, which was large enough to hold 25 Ounces of Water, with common Air, I shut up the Receiver firmly with a Screw. Septemb. 11 The Mercury risen not in the least. Septemb. 12 It was about an Inch high. Septemb. 13 It was raised to 3 ½ Septemb. 14 It was raised to 7 Septemb. 15 It was raised to 10 Septemb. 16 It was raised to 12 ½ Septemb. 17 It was raised to 14 Sept. 18 It was raised to 16 Sept. 19 It was raised to 18 Sept. 20 It was raised to 20 Sept. 21 It was raised to 22 Sept. 22 It was raised to 23 ½ Septemb. 23 It was raised to 27 Inches, no Alteration being observed in the Grapes. Septemb. 24 It was 30 Inches high. Septemb. 25 It was 31. The Colour of the Grapes being turned yellow. Septemb. 26 It was raised to 32 ½ Septemb. 27 It was raised to 34 Sept. 29 It was raised to 35 Sept. 30 It was raised to 35 Octob. 1 The Mercury was 35 Inches high. Octob. 2 It was 36 Octob. 0 It was 36 Octob. 6 It was 36 Octob. 10 It was 35 Octob. 13 It was 32 ½ None of the Air made its way out; but the Cold increased. Novemb. 9 The Mercury had neither ascended nor descended. Decem. 19 The Air was lost. Decem. 20 The Grapes took out of the Receiver were firmer than before, their Taste and Smell discovering them to be mouldy. Factitious Air. Septemb. 10. 77. Having included 2 Ounces of unripe Grapes in a Receiver which was large enough to contain 8 Ounces of Water, and as much of factitious Air of Pears as sustained a mercurial Cylinder of 10 Digits. Sept. 11. The Mercury subsided to 8 Digits. Sept. 12. It ascended 3 Inches. Sept. 13 It risen to 16 Sept. 14 It risen to 20 Sept. 15 It risen to 23 Sept. 16 It risen to 24 Sept 17. It was sustained at 28 Inches; the Colour of the Grapes being turned Yellow. Sept. 18 It was 29 Sept. 19 It was 30 Sept. 20 It was 31 Sept. 21 It was 33 Sept. 23 It was 35 Sept. 24 It was 20 Some Air got out. The Grapes were Yellow. Sept. 24 It was 21 Sept. 25 It was 22 Sept. 26 little Variation. Sept. 27 It was 22 Sept. 29 It was 27 Sept. 30 It was 28 Oct. 1 & 2 It was 28 Oct. 5 It was 30 Oct. 6 It was 31 Oct. 10 It was 31 ½ Oct. 13 It was 31 Nou. 9 It was 13. Some Air made its way out. Nou. 19 It was 29 Inches high. Dec. 20. The Grapes had acquired a greater degree of Firmness, The Taste and Smell being not less grateful than before. In which Experiment the firmness seems to be effected by an exhalation of the Spirits; and it hence likewise appears, that Factitious Air may preserve the Taste, tho' it causes a change in Colour. EXPERIMENT IU. July 18. HAving enclosed two Pieces of Oranges, Artificial Air from Oranges. the one with Common Air, and added as much Factitious Air of Cherries as was sufficient to bear up 12 Inches of Quicksilver, and the other without any addition to the Air contained in the Receiver. July 20. The latter seemed Mouldy; the other not appearing to have undergone any Change. July 23. The Orange contained in the Factitious Air was unalter'd, the Mouldiness of the other being increased. July 26. That in the Common Air seemed Putrid; as likewise the other did, but without Mouldiness. August 1. No farther Alterations appearing in the Oranges, I opened the Receivers, and observed that in the Artificial Air, which held the Mercury 26 Inches high, was well Tasted and Firm; only the Top of the Rind had lost a little Juice; that in the other Reciver seemed Rotten, except the Rind. It may be here observed, that Factitious Air of the Cherries, hath different Effects on several Fruits. EXPERIMENT V. Factitious Air. July 20. 76. Artificial Air from Beef. HAving compressed Air made of Cherries in a Receiver with a Piece of Beef, so that it bore up a Cylinder of Mercury 27 Inches high. July 21 There was no considerable Change in the Height of it. July 22 There was no considerable Change in the Height of it. July 23 There was no considerable Change in the Height of it. July 25 There was no considerable Change in the Height of it. July 26 The Receiver and Cover were separated; the Flesh Stunk. Common Air. July 20. 76. Beef being shut up with Common Air: The Mercury was raised. July 21 0 July 22 1 Inch. July 23 5 ½ July 25 9 ½ July 26 14 ½ towards Night 18. July 27 21 ½ towards Night 25. July 28 The Air got out. Hence it appears, that the Artificial Air of Cherries, hindered the Generation of it from Flesh. EXPERIMENT VI. Common Air. March 14. 76. Artificial Air from Onions. TWO Onions being enclosed with Common Air in a Receiver. March 28. The Mercury on the Sixteenth was depressed ¼ of an Inch, but after was buoyed up 2 ¼. And the Air getting out, the length of the Roots was increased. April 28. They were putrified and corrupted. May 9 The Mercury neither ascended nor subsided, but the Roots were putrified. Factitious Air. March 17. 76. Onions b'ing included with Air obtained from Paste. March 28. They took Root just as they usually do in Common Air. April 28. The Extremities of the Roots began to putrify, perhaps because the Artificial Air might be moister: The Mercury Ascended 9 or 10 Inches. May. 18. One of them began to corrupt: From whence it appears, that Vegetation is not hindered by artificial Air; and it likewise appears, that the Quantity of Air is increased. EXPERIMENT VII. Common Air. August 25. Artificial Air from Grapes. Fix Ounces of Grapes being shut up in a Receiver large enough to contain 25 Ounces of Water. Aug. 26 It's Ascent scarce discernible. Aug. 27 1 Inch. Aug. 28 It's Height was 1 ¼ Aug. 29 It's Height was 1 ¼ Aug. 30. The Mercury subsided a little; the Grapes were not equally altered, as in Artificial Air of Pears. Aug. 31. The Grapes being open to the Atmosphere. Septemb. 7. Their pungent Taste was something abated; tho' they retained their Colour. Factitious Air. Aug. 25. Two Ounces of Grapes being shut up in a Receiver, large enough to hold 8 ½ of Water, so much Air of Pears was thrust in, as was able to raise it 15 Inches. Aug. 26. Some Air getting out, a supply was added, which raised the Mercury to 17 Inches high. Aug. 27. The Mercury subsided to less than 16 Inches; towards night it ascended again to 17 Inches. Aug. 28 It risen to 19 Aug. 29 It risen to 21 Aug. 30 It risen to 22 Aug. 31 It risen to 23 ½ Sept. 1 It risen to 24 Sept. 2 It risen to 24 Sept. and 4 they acquired a Yellowness. Sept. 5. Air got out. Sept. 7. The Grapes were insipid, and of an ungrateful Taste. From this Experiment we may argue for the Power of Artificial Air in changing Colours: It promotes the Generation of Air, and preserves Tastes. EXPERIMENT VIII. Factitious Air. Aug. 2.76. Artificial Air from Gillyflowers. A Gillyflower being enclosed with Air of Paste in a Receiver. Aug. 4. It was moist, and altered its Colour. Aug. 9 It was in some measure altered. Aug. 12. Their Moistness increased gradually without Mouldiness. Aug. 31. It was not so fresh as those in Vacuo. Aug. 2. Common Air. Being enclosed with Common Air. Aug. 4. It was unalter'd. Aug. 9 It was wet, and almost Colourless. Aug. 12. It was very Mouldy. Aug. 4. Vacuum. Two Gillyflowers being shut up in Vacuum. Aug. 4. They seemed moist. But in a year after underwent no Alteration. From whence it appears, that factitious Air renders Colours more subject to change. EXPERIMENT IX. Common Air. July 24. Artificial Air from Apricocks and Plums. A Pricocks and Plums being enclosed in a Receiver. July 28. There was no Change in the Fruit, but that one Plum which was cut in pieces, was a little mouldy. Aug. 11. The Colour Taste and Consistence of the Fruit were all very acceptable. July 24. Artificial Air. The same Ingredients being shut up with so much Artificial Air of Cherries, as kept a Cylinder of Mercury up to 22 Inches. July. 25. It subsided 3 Inches, and risen to 22 again-towards Night. July. 26 It risen 28 July. 27 It risen 34 ½ July. 28 It risen 36 July. 29 It risen 40 July 30 It risen 44 Foot high. Those Apricocks which were cut in pieces were moist, and began to dissolve in Water. July. 31 The Height was 51 Aug. 1 The Height was 60 Aug. 2 It was 65 Foot high. The Fruit being taken out, were of a grateful Taste, and as far as they were immersed in Water, very soft. From whence it is evident, that the Air of Cherries hastens Alterations in Colour, and Firmness in Apricocks. EXPERIMENT X. July 30. PLums cut in pieces, being shut up in Vacuo, and likewise with Common Air; and in another Receiver with Common Air of Gooseberries. Aug. 2. In the latter, they were unalter'd: In common Air they grew mouldy: In Vacuo they became soft. Aug. 5. In the Artificial Air, they became red, soft and moist; In Common Air black and mouldy, yet firm: In Vacuo they were near a Dissolution. August 7. They became soft in Common Air. August 8. They became red instead of Black: Artificial Air seems to promote Alteration. EXPERIMENT XI. Sept. 24. Peaches shut up in a Receiver. FIve Peaches being closed in a Receiver, with Artificial Air of Grapes together with Common Air. Sept. 25 The Mercury was 21 Inches high. Sept. 26 It risen to 23 Sept. 27 It risen to 31 Sept. 28 It risen to 39 Sept. 29 It risen to 42 Sept. 30 It risen to 45 Oct. 1 It risen to 48 Oct. 2 It risen to 48 Oct. 3 It risen to 52 ½ Oct. 5 It risen to 52 ½ The Peaches were Wet. Oct. 6 It risen to 58 Oct. 7 It risen to 58 Oct. 8 It risen to 61 Oct. 11 A little higher. Oct. 19 It risen to 95 Oct. 25 It risen to 61 Very Cold. The Cold abating it Ascended. Oct. 27 Oct. 30 It risen to 61 ●/● Nou. 2 It risen to 59 Very Cold. Nou. 6 It risen to 61 A Thaw. Nou. 7 A little higher. Nou. 9 At the same height. Nou. 9 In a Month it gradually ascended to 8 Inches. April 1. It was 96. When the Receiver was open, as the Air broke out, it emitted several Bubbles; their Taste and Colour were good, the consistence of them was as if they had been boiled: And in three hours' time they were Rotten. Bodies corrupt less in a Mixture of Factitious and Common Air, than in the Latter itself. EXPERIMENT XII. August 4. Pears enclosed in a Receiver. FOur Pieces of Pear being closed with Common Air in a Receiver. August 6. The Colour of this Fruit was equally altered as of others: The Mercury ascended not. August 7. The Mercury ascended a little, the Alteration in the Pears being small. August 8. They were very little Altered; the Cylinder of Mercury was 4 Inches. August 9 It was 4 ½. Aug. 10 It risen to 6 Aug. 11 It risen to 10 Aug. 13 It risen to 16 Aug. 4 It risen to 20 The Pears grew softer. Aug. 15 It was 21 Aug. 16 It was 19 Aug. 17 Air got out. Aug. 8 The Air being got out, and the Fruit taken out, it was rotten. August 4. Other Pieces of the same Fruit being shut up with as much Artificial Air of Cherries as sustained 23 Digits of Mercury above its usual height. August 6. The Colour of them was a little altered. August 7. They were almost all Rotten: The Mercury neither subsiding nor ascending. August 8. They were in some Measure altered. August 10. They gradually became softer: The Mercury being raised 40 Digits. Aug. 11 It risen to 51 Aug. 13 It risen to 61 Aug. 14 It risen to 67 Aug. 15 It risen to 73 Aug. 16 It risen to It Descended, tho' no Air made its way out. August 17. The Mercury was 67 Digits high: No Air got out. August 18. The Mercury subsided not: The Taste of the Fruit was Acid, and their substance very soft; the Air contained in the Receiver likewise, smelling very sharp. August 4. 77. Pieces of the same Fruit being enclosed in a Receiver. August 6. They altered their Colour. August 7. A piece of a Pear became soft: and another in Artificial Air was putrid the Day before. August 8. They were all soft; and one was Mouldy. August 9 Their Rottenness gradually increased. August 11. They were altogether Rotten and Mucid. From this Experiment and the former it appears, that Rottenness is equally promoted, in included and open Air, tho' much faster carried on in the Latter. August 4. 77. Several Pieces of Pears being shut up in Vacuo. August 6 The height of the Mercurial Cylinder was 5 Digits. Aug. 7 It risen to 8 Aug. 8 It risen to 10 Aug. 9 It risen to 12 Aug. 10 It risen to 14 Aug. 11 It risen to 16 Aug. 13 It risen to 20 Aug. 14 It risen to 23 Aug. 15 It risen to 25 Aug. 17 It risen to 28 August 20. They were not in the least Changed till to Day; when being soft, the Mercury was at a stand. August 26. All things Remained as before. From which Experiments it appears, how apt Artificial Air is to soften Fruit. EXPERIMENT XIII. August 21. 77. Apricocks shut up in a Receiver. SIX Apricocks being divided into Quarters, one Piece of each was enclosed in a Receiver. August 22. They seemed Riper. August 23. One piece which touched the Water, acquired Mouldiness, the other beginning to putrify. The Mercury ascended a little. August 24. Those next the Water were not only Mouldy, but all Rotten. August 25. Putrefaction gradually became greater: The height of the Mercury was 7 Inches. Aug. 26 It risen to 15 Aug. 28 It risen to 30 Aug. 29 It risen to 30 The Fruit was almost dissolved. Aug. 30 It risen to 33 Aug. 31 It risen to 38 Sept. 1 It risen to 38 Sept. 2 It risen to 38 Sept. 3 It risen to 38 † A little. Sept. 4 It risen to 41 Sept. 5 It risen to 43 Sept. 7 It risen to 45 Sept. 8 It risen to 46 Sept. 9 It risen to 46 Sept. 22. The Mercurial Cylinder varied little: The Fruit was almost dissolved. Octob. 1. The Taste of the Fruit which remained undissolved was subacid and grateful: The Mercury then standing about 46 Inches high. August 21. 77. A Quarter of each of the same Fruit being placed in a Receiver, which was not sufficiently guarded from the outward Air, August 22. They became as flaccid as if they were withered. August 23. Many were Rotten and Mouldy. August 24. They were wholly putrified. August 21. A Quarter of each of the Apricocks being shut up in a Receiver, and a sufficient Quantity of Artificial Air from Pears added, as raised the Mercury 20 Inches. August 22. The Mercury stood still, but became Riper than those in open Air. August 23. The Alteration was not so great as in Common Air. August 24. They were unalter'd. August 25. They began to yield Air; but the Quantity was not discernible. August 26. They underwent no considerable Change. August 28. They began to be a little moist: Yet the Alteration they underwent was not so considerable as of those in Common Air. August 30. The Mercury Rose 30 Inches above its usual Height. Aug. 31 It risen to 40 Sept. 1 It risen to 40 Sept. 2 It risen to 40 Sept. 3 It risen to 45 Sept. 8 It risen to 49 † A little. Sept. 9 The height was 40 Sept. 11 The height was 38 Sept. 12 The height was less Sept. 13 The height was 33 Sept. 14. The Mercury subsided so far as to disappear. Sep. 22. It risen again to 33 Inches: The Fruit was covered with a Mucor. Octob. 1. The Apricocks were well coloured: But spongy and soft, and of a subacid Taste. August 21. A quarter of each of the aforesaid Fruit, being enclosed with as much Common Air as was able to raise the Mercury 90 Inches above its usual height. August 22. The Receiver bursting with the Elasticity of that Air, the Fruit was enclosed with as much Air as raised the Mercury 60 Inches. August 25. New Air was added, the Fruit was not Mouldy. August 26. They were altogether Rotten and Mouldy. From whence it appears that Corruption is quicker in Artificial, though greater in Common Air. ARTICLE IU. The Effects of Air compressed, different from the Effects of Common Air. EXPERIMENT I, March 21. 77. Onions shut up in a Receiver, TWO Onions being shut up with as much common Air, as was able to sustain 60 Inches of Mercury. March 28. They took Root like others in the Air, no more compressed than that of the Atmosphere. April 28. Onions shut up 8 Days ago, were mouldy: The Extremities of the Roots of those in compressed Air, began to rot: And new Air being put in raised the Mercury 69 Digits. April 29. Those in the compressed Air were mouldy. From this Experiment it appears, that Compression hinders not Vegetation; and tho' Compression seemed to hinder Corruption at the first, yet upon an Intrusion of fresh Air, it was by that promoted. EXPERIMENT II. May 9 HAVING enclosed an equal Proportion of Tulips and Lark-Spurs together in two Receivers; Tulips and Lark-Spurs enclosed in a Receiver. as much Air was squeezed into one as was able to raise Mercury 70 Digits. May 11. Two Tulips in the common Air uncompressed, were mouldy. May 12. Another in the uncompressed Air became mouldy. May 14. All the Tulips and one Lark-Spur became mucid; One Tulip in the compressed Air being likewise mucid. May 17. Three in the compressed Air acquired a Mucidness, yet not so much as those in the Air uncompressed: Two of the Lark-Spurs in uncompressed Air were finewed, but those in the compressed Air, were not. May 21. The Flowers shut up in uncompressed Air were rotten, those in the compressed Air being unalter'd, except that the Mouldiness was rather diminished. May 30. The Flowers being dissolved and taken out, those in the compressed Air were subacid; From these Trials it appears, that Compression hinders Putrefaction. EXPERIMENT III. May 21. 77. HALF an Orange being enclosed in a Receiver, Orange's shut up in a Receiver. and as much in another; to which, so much Air was added, as raised the Mercury 100 Inches above its usual height. May 25. That in the uncompressed Air was more mucid than the former. May 26. The compressed Air getting out, it was supplied by a new Addition. May 30. The Air being daily added as it got out, the Orange in the compressed Air was more mucid than the other. June 1. The Oranges being taken out of the Receivers, that in the compressed Air was much more corrupted than the other, so that, tho' Compression hinders Corruption, yet 'tis promoted as the Quantity of Air is removed. EXPERIMENT IU. May 31. 77. AN equal Quantity of Roses being put into two Receivers, Roses shut up in a Receiver. so much Air was pressed into one of them, as was able to raise the Mercury 90 Inches above the Height it is suspended at, by uncompressed Air. June 11. Those in the uncompressed Air had lost a little of their Colour; but those in the other Receiver had contracted a Yellowness, as if exposed to dry in the open Air, neither were they mucid. June 18. Those in the uncompressed Air were very little altered, but those in the compressed Air, grew yellower and yellower: They were neither dry nor flaccid, nor was there any considerable Alteration in their Smell. But both being exposed to open Air, those were sooner altered which were in the uncompressed Receiver. From whence it appears, that sometimes compressed Air is more disposed to alter Colours, than uncompressed; and it may not be amiss to observe, that the Roses after this manner shut up, did not acquire the least Mucidness, but only a yellow Colour: But when the Experiment was tried with Tulips and Lark-Spurs, the Success was different. See Exper. II. EXPERIMENT V. June 1. I Put one half of an Orange in one Receiver, Orange's shut up in a Receiver. and the other half in another, adding to one, as much Air as was able to raise the Mercury, an hundred Inches above the Height it was sustained at in the other. June 6. Both of them became mucid, but especially that which was kept in the compressed Air: In this Experiment it was to be noted, that the Air which was compressed in the one Receiver, daily got out, and was as often renewed. June 11. The Orange in the uncompressed Air acquired no further Mucidness, though the other did. June 18. The Mucidness of the Orange in the uncompressed Air decreased; And tho' the other Orange ceased to increase its Mucidness, as long as it was not supplied with fresh Air, yet so much fresh Air being shut up with it, as was able to raise the Mercury 80 Digits, June 20. It became much more mucid in two days time. Whence it appears, that as the Quantity of Air is more or less, so the Body enclosed in it, is more or less mucid. EXPERIMENT VI. June 17. 77. HAVING shut up two Shrew-mices, Shrew Mice shut up in a Receiver. and each of them in a distinct Receiver, we added so much Air to one of them, as raised the Mercury 30 Digits: But the Mouse in the uncompressed Air, was shut up, about 5 and 52 1, 6 1 after the other. The Mouse in the compressed Air seemed to lose its Strength a great deal sooner than the other, the Motion of its Breast being not near so quick; nevertheless, about 6 and 18 1, that in the common Air died Convulsive, yet that in the compressed Air, continued to be as well as it was an hour and half ago. About 11 of the Clock that in the compressed Air continued Respiration; but about 4 in the Morning it was found dead, in the same Posture it was 7 hours before in; whence we may guests, that it was free from Convulsive Fits. The Mouse in the common Air had consumed, so much of it, that the Mercury in the Gage, which stood at 29 Inches, was raised to 30 when the Receiver was opened. From whence it appears, that compressed Air contributes to the prolonging of Life. EXPERIMENT VII. June 13. 77. I Enclosed 4 Flies in a Receiver, Flies shut up in a Receiver. with as much Air as raised the Mercury 60 Digits above its usual Height; 3 others at the same time being shut up with common Air. July 14. In the Morning they were all well. In the Afternoon 2 of those in the compressed Air were dead. About 5 all in the compressed Air were dead but one, and the 3 in the common Air were alive. July 15. In the Morning, those in the common Air were dead; but that in the compressed Air being taken out, flew speedily away. From hence it appears, that they died rather for want of Nourishment, than Air; since that which survived in the compressed Air, and had the Bodies of the other to feed upon, was not distempered. EXPERIMENT VIII. June 15. EIGHT Flies being included in two distinct Receivers, Flies shut up in a Receiver. and the Air in one compressed more than in the foregoing Experiment. June 16. Two in the common Air, and one in the compressed were dead in the Morning. In the Afternoon all in the common Air seemed dead. June 17. All, except one in the compressed Air, were dead. From this and the foregoing Experiment it appears, that the Compression or Rarefaction of the Air, affects Flies very little, except there be almost a complete Vacuum. EXPERIMENT IX. June 18. TWO Frogs being enclosed in two Receivers, Frogs enclosed in a Receiver. shut up by the help of Screws, the one with common Air, and the other with an Addition of as much as raised the Mercury 70 Digits. June 19 No Alteration was perceived. June 20. The Frogs were alive, and the Air seemed to be increased. June 21. In the Evening, that in the common Air was dead. June 23. In the Morning, that in the compressed Air was dead. Whether the Compression of the Air, or Disposition of the Body of the latter contributed to prolong its Life, must be determined by further Observations. EXPERIMENT X. June 18. 77. Orange's conveyed into a Receiver. TWO halves of an Orange being shut up in two Receivers with Screws, so much Air was added to the one, as sustained the Mercury 90 Digits. June 22. That in the common Air was mouldy: And at 3 a Clock Afternoon, the other had contracted a Mucor. June 23. That in the common Air was more mucid than the other. June 24. That in the compressed Air was all over mouldy. June 28. That in the common Air had lost its Mouldiness: The other was unalter'd. June 30. Being taken out, that in the common Air was half rotten; the other, wholly putrified, and mucid. From hence it appears, that as the Quantity of Air is greater, so is the Body contained more mucid. The Mouldiness in the compressed, increased more intensely, tho' it began not so soon. EXPERIMENT XI. June 29. 77. Roses enclosed in a Receiver. TWO Receivers stopped with Screws containing Roses, so much Air was squeezed into one, as raised the Mercury 90 Digits. July 14. The Roses in the common Air were altered. But the others began to whither and look yellow about 4 days ago. July 17. Being taken out, those in the compressed Air were much corrupted, and of an ungrateful Smell; The others had undergone very little Alteration. From hence it further appears, that the Quantity of Corruption depends on the Quantity of Air. EXPERIMENT XII. July 4. A Limon being divided, and shut up in two Receivers with Screws, so much Air was added to one, as sustained the Mercury 90 Digits. July 7. Both pieces seemed to acquire a Mouldiness at the same time. July 17. That in the compressed Air, was much more hoary and putrid than the other. This Experiment does not only confirm what was inferred in the foregoing, but also that a Triple Compression of the Air in Respect of a Limon, is too weak sensibly to retard the Production of Mouldiness or Finew. EXPERIMENT XIII. July 18. 77. Gillyflowers enclosed in a Receiver. ONE parcel of Gillyflowers being enclosed in a Receiver with common Air, and an equal parcel in another, with as much compressed Air, as sustained the Mercury 100 Digits above its wont Pressure. July 23. Those in the compressed Air were covered with a Mouldiness: but the others were only moist: The Air was subsided 30 Inches. July 25. Those in the compressed Air were more compressed than the others, and had lost their Colour. July 26. Those in the compressed Air were wholly putrified, and covered with a hoary Finew; the others were only moist in some places. August 1. Those in the compressed Air being taken out, were rotten and stunk; the others were moist, retained their Colour, and smelled not at all offensive. This Experiment confirms, That the Quantity of Air doth increase Corruption; and also that Mouldiness is not produced, but in compressed Air. EXPERIMENT XIV. July 21. 77. A Shrew Mouse in common Air. TO try whether a Shrew-Mouse would consume or produce Air, I shut it up in a Recipient with common Air. After 2 hours some was consumed; but the Mouse died. July 24. Toward Evening, the Mercury seemed a little higher. July 25. A great deal of Air was produced de novo. July 26. It increased considerably. From whence it appears, that living Animals consume, and dead ones produce Air. EXPERIMENT XV. August 31. Pears enclosed in a Receiver. AS much Air was pressed into a Receiver which contained Pears, as sustained the Mercury 30 Digits above the usual height. Sept. 1. The Mercury was depressed. Sept. 2. It sunk to 25 Inches. Sept. 3. It was raised to 26. Sept 4. It was 28 Digits high. Sept. 8. The Receiver being opened, 5 of the Pears had lost their Firmness, but 2 retained. August 31. The same sort of Pears being shut up with common Air. Sept. 1. The Mercury was depressed a little; I suppose by the Cold. Sept. 2. It was not changed. Sept. 3. It was raised a Digit. Sept. 4 The height of it was 4 Sept. 5 The height of it was 6 ¾ Sept. 6 The height of it was 6 ½ Sept. 7 The height of it was 12 Sept. 8 The height of it was 20 Being taken out, they retained their Taste and Firmness, much better than in Vacuo. Aug. 31. The same sort of Pears being shut up in Vacuo, so much External Air broke in, as sustained the Mercury an Inch. Sept. 1 The Height of it was 4 Sept. 2 The Height of it was 8 Sept. 3 The Height of it was 12 Sept. 4 The Height of it was 16 Sept. 5 The Height of it was 19 Sept. 6 The Height of it was 23 Sept. 7 The Height of it was 27 Sept. 8 The Height of it was 30 Being taken out, they had lost their Taste in a great measure, but reserved their Firmness. From these Experiments it appears, that as the Compression is greater, the less Air is produced. EXPERIMENT XVI. Decemb. 7. A small Bird. A Small Bird being shut up in a Receiver, which was large enough to contain 20 Ounces of Water, began to be ill, before I had set the Screw; but as much Air being pressed in, as raised the Mercury 30 Digits, she seemed to recover; but after a little time, she began to be ill again: yet so much Air being thrust in, as raised the Mercury to 45 Digits, she recovered a second time; But some time after she began to gasp again; nevertheless, 28 Minutes after the Receiver was opened, she got out, and was very well. EXPERIMENT VII. Jan. 20. 1678. A Shrew-Mouse in a Wind-Gun. A Shrew-Mouse being shut up in my Wind-Gun, and the Air so far condensed, that it reduced it to a twentieth Part of the Space it possessed before, upon a Discharge of that Air, the Elliptic Hole being opened, the Mouse was taken out dead. Another Mouse being put in, and the Air compressed to a third Part of its Space, it was taken out well. The Experiment was repeated, and the Air 7 or 8 times condensed, by which the Mouse seemed not the least prejudiced; The same Experiment being repeated, the Air being 7 times compressed, when the Mouse had been shut up 24 Minutes, upon a Discharge of the Air, after repeated Groans, died. From whence it appears, that compressed Air is noxious, yea, mortiferous. EXPERIMENT XVIII. Jan. 28. 78. A Shrew-Mouse in compressed Air. I Put a Shrew-Mouse into a Glass, to whose Neck I tied a Bladder, stopping the Orifice, which being shut up in a Receiver, when the Mouse began to be sick, by pressing new Air into the Receiver, the Bladder was straitened, and tho' new Air could not penetrate into the Mouse; yet the Air it was shut up in being compressed, it was much better, and being taken out, in a short time recovered. Another Mouse being shut up after the same manner, till it could scarce breathe; when the Air was compressed, its Respiration seemed abated; upon which, the Receiver being opened, and the Mouse exposed to the Air, it could not breath much more freely; yet when Air was blown upon it with a pair of Bellows, it seemed relieved; but being again shut up with compressed Air, it breathed less frequently, and died. March 25. A Mouse being shut up in an Instrument before described, when I perceived the Mouse sick, I intruded Water into the Receiver, so that the Air was reduced into half the Space it possessed before; upon which, the Mouse breathed more rarely; but the Air being successively compressed and left to its liberty again, the sick Mouse seemed to breathe more lively in the common Air, than in the compressed. Whence I conjectured, that the Air is to Animals as Food, which ought to bear some proportion to the Strength of the Animal. In Confirmation of which Conjecture, I shut up a Mouse in my Pneumatick Engine, and rarified the Air so much, that it possessed three times the Space it did before; upon which, the Mouse seemed better, but presently began to be sick, yet underwent no sensible Alteration upon an intromission of Air: The like success happened three times successively, tho' at the last the Mouse died. ARTICLE V The Effects of Artificial Air upon Animals. EXPERIMENT I. May 5. 77. A Bee, A Bee in Artificial Air. together with distilled Vinegar, and Powder of Coral, being conveyed into a Receiver; I so contrived the matter, that when the Receiver was exhaustod, the Coral fell into the Vinegar: But the Air produced, had no Effect on the Bee; yet when it had been a little exposed to the Air, it began to move: Whence we may gather, that Artificial Air is not fit for Animals to live in. EXPERIMENT II. August 12. 76. TWO Flies being contained in a Receiver, Flies in Artificial Air. with as much Artificial Air of Goosberries as sustained 26 Inches of Mercury: And two others being shut up in Vacuo, adding common Air enough to sustain 23 Digits of Mercury, upon which, in a quarter of an hour the latter began to fly, but those in the Artificial Air lay without motion. Aug. 13. Those in the Artificial Air seemed dead; the others were well; nor did the former recover, tho' exposed to common Air a whole day. Aug. 18. The same Experiment was repeated with the like Success. This Experiment is a further Confirmation, that Artificial Air is noxious to Respiration. EXPERIMENT III. June 22. 77. PASTE being contained in 3 exhausted Receivers. Paste included in 3 Receivers. June 23. Into one I put a perfumed Cone kindled, which was extinguished in a Minute, as soon as the Receiver was stopped; yet in common Air, it burned bright for some time after the Receiver was stopped. Another Experiment being tried with a Fly, I observed, that tho' when it was shut up in Artificial Air for some time, it seemed dead, till revived in the Sunbeams; yet another shut up in common Air, received no damage: The like Success followed, when we tried the Experiment a second time, save that the Fee being taken out of the Artificial Air, was something longer before she recovered. From hence it appears, that Artificial Air is prejudicial to Fire as well as to the Life of Animals. EXPERIMENT IU. Jun. 25. 77. HAving enclosed Paste in four Receivers, two of which were exhausted, and the other two but half evacuated. June 26. Those which were half full of common Air, being filled with Artificial, I put two Flies into one of them, which were deprived of Motion, as soon as they came to the Bottom; A Third, and then a fourth, successively being put in, they continued to live longer; yet after some Convulsions, lay unmoved and supine; But being removed into common Air, in a little time they came to themselves: Those Flies that were put into Receivers, which only contained common Air, were well sooner. June 27. One of the Receivers which had been wholly exhausted of common Air, being casually thrown down, gave way to an Ingress of external Air; A Frog being being put in, was not much disaffected. June 30. The fourth Receiver being forced away from its Cover, I put a Frog into it, which after five minutes high Convulsions, lay without Motion four minutes; and then being taken out of the Receiver, continued so 46 minutes; but in five minutes more grew very well. From hence it appears, that if Artificial Air be mixed with common Air, it is so much the less prejadicial to Animals. EXPERIMENT V. June 28. I Enclosed Paste in four Receivers, A Frog in Artificiab Air. 3 of which were wholly exhausted of common Air, but the fourth was left half full. June 29. One of the Receivers being full of Artificial Air, and a Frog put into it, after it had been violently Convulsive for 4 or 5 Minutes, and lay void of Motion for about a Minute, being taken out of the Receiver, in about 5 Minutes, began to move, and was well again in a little time. A Frog being put into another Receiver with Artificial Air, was Convulsive for about 7 Minutes, and then lay void of Motion for about a Minute; yet when it was taken out of the Receiver, it began to struggle and move, after which Motions, which seemed to be the Relics of its Convulsions, it lay for about half an hour void of Motion again; yet, at the last, it recovered a second time. A Frog being cast into that Receiver, which was but half exhausted, for ten Minutes seemed Convulsive; and then, lying still for about a Minute, the Receiver being opened, within half an hour recovered power to move again: But in the Experiment it was to be noted, that the Quantity of Artificial Air, was so much increased before the Frog was cast in, that part of it, and consequently some of the common Air made its way out. A Frog being shut up in a Receiver with common Air. July 1. In the Morning it was alive, in the Afternoon dead; It lived near 48 hours. June 30. A Frog being shut up with Artificial Air wholly, after 7 Minutes Convulsions died; nor did it recover, tho' taken out 2 Minutes after. July 1. It did not recover: Hence it appears further, that Artificial Air is most detrimental, when least common Air is mixed with it. EXPERIMENT VI. June 30. Paste included in a Receiver. PASTE being shut up in two exhausted Receivers. July 4. Some little Air having got into one Receiver, I put a Shrew-Mouse into it, who after vehement Convulsions, died in a Minute. A Snail being put into the other Receiver, continued to move vehemently for a quarter of an hour, after which time, its Motion gradually declining, in a quarter of an hour it seemed dead, but in a short time grew well again. Flies being shut up in another Receiver, were not at all prejudiced, too much External Air having got in. From hence it appears, That Artificial Air is prejudicial, upon the Account of some venomous Quality; and not only by defect of Common Air; since Snails lived a longer time in Vacuo. See Art. VI Exp. III. EXPERIMENT VII. July 5. 77. A Frog in Artificial and Common Air. HAving transmitted Artificial Air of Cherries out of One Receiver into another, full of Common Air, in which a Frog was contained; so much Water flowed out, as was sufficient to give way to the Ingress of the Artificial Air. Upon which the Frog being Convulsive for about a Quarter of an hour, lay still; yet soon recovered again, when exposed to the Air. This Experiment seems to prove, that Artificial Air of Cherries is less pernicious than that of Paste; See Exp. V. EXPERIMENT VIII. July 9 77. Goosberries enclosed in Vacuo. GOosberries were shut up in three empty Receivers. July 20. So much Air was produced, as separated the Cover from the Receiver: Two Flies being cast successively in, presently Died; a third seemed Convulsive; a fourth in less than a quarter of a Minute lay without Motion: The Receiver being cleared of the Artificial Air it, grew well. July 24. A Shrew-Mouse being shut with Air from Goosberries, Died in half a Minute. Hence it may be inferred, that Air produced from Fruit is less prejudicial than Air obtained from Minerals; for July 20 a Mouse being shut up with Air produced from Gunpowder, Died in a Quarter of a Minute. EXPERIMENT IX. July 5. 77. Paste in Vacuo. Passed being contained in four exhausted Receivers. July 6. One was forced from its Cover: Some Common Air got in before it could be stopped. A Shrew-Mouse being put in, was Convulsive a Minute and ½ and then remained moveless: Being taken out, after some Convulsive Motions, Died. July 7. A Bird shut up as the Mouse was, in a quarter of a Minute Died: A Bird of the same kind being shut 4 Minutes with common Air, was very well. July 9 The same Bird which continued well in the Common Air, Died when enclosed with Artificial Air, in a quarter of a Minute. An Adder being shut up with Artificial Air, in 2 Minutes began to be ill; and in 24 Minutes was deprived of Motion, and tho' 6 Minutes after it was exposed to the Air, yet it recovered not. July 10. There was no hopes of Recovery. EXPERIMENT X. July 12. 78. A Bird in Artificial Air. A Bird shut up with Air from Raisins Died in ¼ of a Minute. July 18. A Shrew-Mouse being shut up with the same sort of Air, after 2 Minutes seemed ill and void of Motion; yet in 2 or 3 Minutes was well again. EXPERIMENT XI. Octob. 1. 78 A Shrew-Mouse in a Receiver. A Shrew-Mouse being shut up an hour in Common Air could scarce Breath. Another being cast into the same Receiver, before the Stopple was clapped on again, some fresh Air broke in, by which the first Mouse was refreshed; yet about an hour after both died. About 4 after Noon, another Mouse being clapped in very cautiously, died in 3 Minutes. Whence it appears, that the same Air is not long fit for Respiration. EXPERIMENT XII. April 28. A Snail in Artificial Air. A Snail being enclosed with Air from Paste, froathed, and contracted and expanded successively, till in 4 Minutes it became void of Motion; At a quarter of an hours end, being taken out, it was void of Motion: Yet being pricked with a Pin, a quarter of an hour after moved a little. A Snail being shut up when that Air was blown out, was not ill at all: whence it appears, that Artificial Air is more prejudicial to Animals, than a Vacuum. EXPERIMENT XIII. Jun. 22. 78. Green Pease in a Receiver. IN a Day's time green Pease yielded Air enough to sustain 10 Digits of Mercury. Jun. 23. The Mercury was 30 Digits high. Jun. 24. It risen no higher. The Cover and the Receiver stuck not together, yet no Air got out. Jun. 26. The same Pease being shut up in the same Empty Receiver. Jun. 29. A Snail being thrown in, and the Receiver being full of Factitious Air, it frothed, and frequently contracted and expanded; but after six Minutes, lay still 2 or 3. Being taken out it moved a little. Whence we gather, that Factitious Air of Pease is not so prejudicial to Snails as that of Paste. See Experiment XII, XI. The Factitious Air being blown out, a Snail did very well in the Receiver. In this Experiment it is observable, that Pease sooner yield Air in Vacuo, than in Compressed Air. ARTICLE VI Animals in Vacuo. EXPERIMENT I. Jun. 22. 76. A Butterfly in Vacuo. A Butterfly moved 3 hours in Vacuo, and recovered its Motion when lost, upon an ingress of Air. Being hung by a thread, tied to one of her horns, it was moved from one side of the Receiver to the other by the Motion of its Wing, but when the Air was drawn out, we could not move the Thread from a perpendicular Posture. EXPERIMENT II. July 12. 76. Two Flies in Vacuo. TWo Flies being shut up with as much Air as sustained 10 Inches of Mercury, the biggest seemed presently Dead, tho' the other lived 24 hours. When both Flies lay as Dead, so much Air was let in as raised the Mercury to 15 Inches; upon which the less Fly began to move. Infects may breath in rarified Air sooner than in Artificial. EXPERIMENT III. May 1. Two Snails in Vacuo. TWo Snails seemed well for the space of an hour in Vacuo and crept up to the Top of the Receiver; but in two hours fell down void of Motion: 4 hours after, being exposed to the open Air they began to move. Whilst they were shut up they helped to produce Air enough to raise the Mercury ¼ of an Inch. They lived longer in Vacuo, than others in artificial, Art. V Exp. VI. EXPERIMENT IU. August 12. 76. Fly-Blowings in a Receiver. FLy-blowings were put into an empty Receiver. August 14. Worms were formed: So much Air got in as was sufficient to sustain Mercury 15 Digits. Whence it is evident, Infects may be produced and live in very rarified Air. See Exp. VI and VIII. EXPERIMENT V. March 17. 77. Frogspawn being divided into two equal Parts, Fog-Spawn. and each of those included in a distinct Receiver, the Spawn being first put into glass Vessels; one of the Receivers was exposed to the Sun, being totally exhausted; the other was left full of Air. That in Vacuo swelled into Bubbles. May 2. The Bubbles remained in Vacuo. No Frogs were produced in either. 3 Days since the Bubbles disapeared; and the Spawn turned into a green Liquor. July 2. The Spawn in Vacuo, and the Water contained in the Vessel being raised in Vapours, stuck to the sides of the Receiver, and there condensed: The Spawn and Water in the Common Air retained their own Form. EXPERIMENT VI. August 16. 77. I Enclosed Flies Eggs in an empty Receiver. Flies-Eggs. August 29. No Worms being produced, I let the Air into the Receiver. Sept. 4. They produced nothing: This Experiment compared with the IV, seems to show, that tho' Infects may be produced and live in Air highly rarified, yet they cannot in Vacuo. EXPERIMENT VII. June 15. A Frog in Vacuo. A Frog enclosed 14 hours in an exhausted Receiver, Died. June 16. The Experiment being repeated; in 2 hours the dead Frog afforded some Air. June 18. The Frog in Vacuo was swelled; but the Air being let in, it was more lank than before. Artificial Air is more prejudicial than a Vacuum to the Life of such Animals. See Exp. IV, and VII, of Art. V. EXPERIMENT VIII. August 3.78. FLie-Blowings sticking to Flesh being shut up in Vacuo. August 12. No Worms generated. August 15. There being no Alteration in the Eggs; Air was let into the Receiver. Sept. 15. They produced nothing. This is a confirmation of the Inference drawn from Exp. IU. EXPERIMENT IX. April 22.78. VInegar full of small Eels, Vinegar with Eels in Vacuo. or Vinegar Worms was shut up in Vacuo. August 29. The Worms still moved, the Number being fewer than before. Sept. 6. Yesterday they moved: To day they were all dead. Those left in the open Air were as lively as before. Whence it is evident, that the Air influences even those diminutive Animals. ARTICLE VII. Fire in Compressed Air. EXPERIMENT I. May 14. I Enclosed such a Cone in a Receiver, Perfumed Cones in Vacuo. as is usually wholly consumed in the open Air before extinguished, and then intruding as much Air as raised the Mercury 120 Digits high above its usual height, I kindled the Cone with a burning Glass; when ⅞ parts of an Inch were consumed and the Receiver filled with Smoak, I took it out, and found that the outside was only burnt, the inner Parts being left untouched. Another Cone being shut up with uncompressed Air, in a Receiver something larger, much less of it was consumed, than of the former. EXPERIMENT II. May II. A Perfumed Cone being enclosed in a Receiver, and kind'ld in uncompressed Air, being weighed when the Fumes were condensed, it had lost a Grain. Another being shut up with as much Air as elevated the Mercury 90 Inches, lost 4 Grains more than the former. So that the more Air is contained in the Receiver the greater is the Consumption of the Matter burning in it. EXPERIMENT III. May 17.77. A Presumed Cone being shut up with a Screw in a Receiver, with as much Air as sustained 60 Inches of Mercury above its usual height, being set on Fire with a Burning-Glass, it lost 3 Grains and a half. The Experiment being repeated in Air compressed so much as to sustain 120 Inches, lost 7 ¾ Grains. May 17. The Experiment being tried, when the Mercury was at 97 Inches, it lost 6 Grains. This Experiment confirms the Inference drawn from the foregoing, and shows that the Consumption bears a greater Proportion to the Compression, than the Compression to the Consumption. May 18.77. A perfumed Cone being shut up in a Receiver, 7 times as big as before, lost 3 ¼ of its Weight; which Air, had it been compressed into a 5th part of that Space, the Cone would have lost 10 Grains. Whence it appears, that the Condensation of the Air promotes the Consumption of the Matter contained in it. EXPERIMENT IU. May 19.77. THE same Experiment being repeated in a Receiver closely stopped with a Screw, the Cone lost a Grain and a quarter. May 21. The same Experiment being repeated, and the Cone set on fire, it lost 4 Grains. May 23. It was twice repeated, but the Cone not being well fired; In one it lost ¼ of a Grain; in the other, a whole one. May 24. The Cone lost 1 Grain and ¼ The Cone being taken out, and cleansed of the Soot, it lost in a Receiver, 6 Grains ½. In an uncleansed Receiver it lost 3 Grains in Weight. May 25. In a cleansed Receiver it lost 6 Grains ½. In one well cleansed after it lost 7 Grains ½. In a Receiver unwashed, the Cone would scarce be kindled. May 26. In a Receiver unwashed, in the middle of a Sunshine Day, the Burning-Glass being long applied, it was 8 Grains lighter. Whence it appears, that tho' the Consumption of the Matter be not always the same in the Quantity of Air, yet it is greater, according to the Degrees of Compression. EXPERIMENT V. May 22. HAving enclosed a perfumed Cone with so much Air as raised the Mercury 30 Digits above its usual height; it lost 1 ¾ of a Grain. May 23. The same Experiment was tried with the same Success. The same Experiment being tried again, the Receiver broke into 100 pieces. See Exper. 3. yea in Exp. VI of Art. II. tho' it resisted Air compressed enough to sustain 198 Digits, yet another time it was broke with a sixth part of that Pressure: Therefore a Man aught, in trying such Experiments, to guard his Head, lest a Receiver accidentally breaking, should fly in pieces and wound him. ARTICLE VIII. Fire used to produce Air. EXPERIMENT I. June 4. 76. Paper besmeared with Sulphur. PAper besmeared with Sulphur, and burnt in Vacuo, yielded Air, which lasted 2 Days without Diminution. EXPERIMENT II. June 15. Hartshorn in Vacuo. Hartshorn burnt in Vacuo, yielded some Air. June 17. Air produced by Hartshorn was soon destroyed; but if it lasted an hour undiminish'd, it usually continued a considerable time. June 19 Hartshorn taken out of the Receiver yielded a fetid Oil, but no Volatile Spirit. EXPERIMENT III. June 21. Amber in Vacuo. AMber being burnt in a Receiver, ascended in Fumes up to the Top, and thence reflected downwards; but burnt in Vacuo, they risen not above a Digit at the first; but afterwards it risen almost to the Top: The Mercury in the Gage was not altered in its height. June 22. Water, in which the Receiver was immersed, got into the Receiver. July 8. No more Water got in: Nor did the Amber produce the least Air. EXPERIMENT IU. Jan. 18. 77 Camphire included in a Receiver. TWO Drachms of Camphire being put in an empty Receiver upon a Digesting Furnace. Jan. 19 It was sublimed into Flowers; no Air was produced. EXPERIMENT V. May 24. 76. Sulphur Viu. melted in a Receiver. SULPHUR Viu. being melted in an exhausted Receiver by the help of a Burning-glass, yielded not Air. EXPERIMENT VI. July 19 PASTE included in a Receiver and burnt, afforded so much Air, that the Cover which before could not be moved without difficulty, easily parted from the Receiver. ARTICLE IX. Concerning the Production of Air in Vacuo. EXPERIMENT I. Sept. 9 76. Dried Grapes in Vacuo. AN Exhausted Receiver being half full of dried Grapes. Sept. 10 It ascended ½ Sept. 12 It ascended ½ Sept. 14 It ascended ⅜ Sept. 17 It ascended ⅜ Sept. 22 The Ascent was ⅝ Sept. 27 The Ascent was ⅝ The Height was 3 Digits. Octob. 11. The Mercury was 6 Digits high. Sept. 9 76. A Receiver being half full of dried Figs, the Air was drawn out till it stood at 3 Inches. Sept. 10. No Air produced. Sept. 17. No Air. Whence it appears, that there is no Regularity in the Production of Air from dried Fruits. EXPERIMENT II. August 5. 76. Pears and Apricocks. PEARS and Apricocks were shut up in Vacuo. Aug. 6. In 18 Hours the Mercury was raised 2 Inches; In ten Hours more the Height of it was 3 Digits. Aug. 7 The height was 5 Aug. 8 The height was 6 ½ Aug. 9 In 14 hours it was 7 ¼ Inc. hig. Aug. 10 The height was 8 ¾ Aug. 11 The height was 10 ¾ Aug. 12 The height was 12 ¼ Aug. 13 The height was 14 ¼ Aug. 14 The height was 16 Aug. 15 The height was 18 Aug. 16 The height was 20 Aug. 18 The height was 25 Aug. 19 The height was 29 Aug. 20 The height was 31 ½ Aug. 21 The height was 32 ½ Aug. 22 The height was 34 Aug. 23 The height was 35 Aug. 26 The height was 38 ½ Aug. 29 The height was 41 Sept. 1 The height was 42 ½ Sept. 4 The height was 44 Sept. 7. The three last Days being hot, it was raised to 46 ¼ Sept. 10 The height was 47 ½ Sept. 13 The height was 44 Sept. 23 The height was 48 Sept. 27 The height was 50 ½ Nou. 5 The height was 52 ⅓ Nou. 28. The Apricocks were reduced to Water; the Skin being severed from the Pulp, no more Air was produced. Jan. 10. 77. It was a hard Frost, at which time the Mercury came to 57 Inches. Upon a Thaw, it was depressed to 23. March 3. The Apricocks were putrified and had lost their Colour. Hence it is evident, that Apricocks afford Air almost as fast in their wont Pressure as in Vacuo. EXPERIMENT III. June 20. 76. Sour Cherries. Sour Cherries whole, being put into one Receiver, and others cut into another; The whole ones raised the Mercury in two hours, 10 Lines; the dissected ones, 20. June 21. The whole ones raised the Mercury to 3 Inehes; the other Gage was spoiled. June 26. The whole ones raised the Mercury 15 Digits; The other Receiver was full of Air. July 9 The Receiver being removed from its Cover, I eat a Cherry, which was well tasted: The rest being included in Vacuo, and some of them broke, in an hour raised the Mercury 2 Digit. July 10. The Mercury ascended not, because the Gage was spoiled. July 15. The Cover was severed from its Receiver. Whence it appears, that dissected Fruits produce Air sooner than whole ones. EXPERIMENT IU. June 9 77. Cherries in Vacuo. CHerries being put into a Receiver, raised ¼ of a Digit of Mercury, in an hour. Jun. 10. The Mercury was raised in 18 hours to the height of 11 Digits. June 11 It risen to 15 June 12 It risen to 15 † June 13 It risen to 22 June 16 It risen to 30 June 18 the Receiver was opened. Fruits of the same kind in France filled their Receiver in 2 Days; and probably there may be the like difference in other Fruits, in several Countries. EXPERIMENT V. June 12. 76. Cabbages in Vacuo CAbbages being included in a Receiver, in an hours time raised the Mercury a Line. June 13. It was raised to 10 Digits. June 17. It was raised almost to the Top of the Gage; the Cabbages being very little altered. June 19 Having been 2 days exposed to the Air, were corrupted and blackish; being shut up in Vacuo, they raised the Mercury ½ an Inch. June 22. It was raised to the height of 1 ½. June 23. No more Air being produced, the Cabbage was taken out: It stunk much: So that I suspected, that Bodies have afforded as much Air as they can before they putrify. EXPERIMENT VI. May 29. 76. Oranges in Vacuo. HAving shut up two pieces of Orange, which weighed 4 Ounces, in 2 exhausted Receivers, large enough to hold 10 Ounces of Water. June 10. They removed the Receiver from its Cover; upon which, I shut them up in an exhausted Receiver, capable of containing 8 Ounces of Water; upon which the Mercury ascended ½ of a Digit. June 13. It was almost 2 Digits high. June 16. It ascended about 3 Lines. June 21 It ascended not one Line. July 18. The Mercury was no higher, but some Mouldiness appeared. EXPERIMENT VII. April 27. 76 A Tulip in Vacuo. A Tulip being shut up in a Receiver, with as much Air as raised the Mercury 2 Digits. May 2. That which before was stripped, put on a dark Red, and became moist: It afforded but little Air. EXPERIMENT VIII. April 22. 76. A Limon in Vacuo A Limon shut up with a Mercurial Gage 3 Digits long. April 24 It was 1 ½ Digits high. April 25 It was 2 Digits high. April 26 It was 4 lines higher. Apr. 27 It risen 1 Line Apr. 28 It risen 1 Line Apr. 29 May 3. In four Days it ascended a little above a Line. May 3. 77. The Limon was a little altered; The Mercury was raised to the Top of the Gage. Jan. 1. 17. The Limon had contracted a Yellowness and Moisture. EXPERIMENT IX. March 16. 67. An Apple in Vacuo. AN Apple which began to putrify, was put into one Receiver, and a bruised one into another. May 15. The bruised Apple appeared wholly rotten; and the Receiver was forced from its Cover. The other Apple was unalter'd. Aug. 20. That which before began to putrify, was yet unalter'd; It tasted grateful, but subacid; The Pulp was of a mealy Consistence. This Confirms the Inference from the 5th Exp. of this Article. EXPERIMENT VII. May 17. 76. Milk in Vacuo. AN equal Quantity of Milk being shut up in common Air, and in Vacuo. May 18. That in the common Air was covered with Cream; the other, with Bubbles. May 19 The Bubbles swelled more and more, the Mercury was raised a little. May 20 The Bubbles swelled more and more, and the Milk seemed curdled: The Mercury in the Gage being raised to the Top. The Milk in the free Air was evidently curdled. May 22. The Milk in Vacuo being curdled, yielded more Air yet, almost all the Bubbles being broke: From this Experiment it appears, that Milk is sooner coagulated in open Air than in Vacuo. June 20. The Milk in the free Air stunk, and was full of Worms; and emitted several large Bubbles when the Air was drawn out; the Worms moved vehemently, and all lived four hours. All the Bubbles on the Milk in Vacuo, were broke, and it continued coagulated. May 19 77. Some Whey in Vacuo, was poured out of a Vessel into a Receiver about 4 days ago, it seemed limpid like Water: The Whey remaining in the Vessel, was sufficient to separate the Butyrous from the Caseous Part. To day the Milk stagnant in the Receiver, seemed to be got out; the Cover being forced from the Receiver. Towards night, the Milk being taken out of the Receiver, was found acid, both in Smell and Taste: After a little time, the limpid Whey disappeared, being mixed with the Caseous and Butyrous Part. May 24. The Butyrous Part vanished, and the Milk began to smell amiss. June 1. The Milk had not very bad Smell, nor had it produced Worms, but grew dry, and then the Mice eat it up. In this Experiment the following Particulars were remarkable. First, That the Coagulation was slower when the Air was drawn out. Secondly, The Weight of Butter, Whey or Cheese, is not the same in the Air, as in Vacuo, because one swims on the Top of the other. Thirdly, The Putrefaction of Milk is retarded, by drawing out the Air. Fourthly, Milk by being kept in Vacuo, is not unfit to generate Worms, when exposed to common Air. EXPERIMENT XI. Sept. 5. 77. Urine in Vacuo. HAving enclosed 3 Ounces and 3 Drachms of Urine in a Receiver, capable of holding 10 Ounces. Sept. 7. The Mercury was raised 2 Digits. Sept 8. It was somewhat higher. Decemb. 5. The Mercury ascended to the height of 3 Inches. The Urine was unalter'd. Decemb. 6. Urine was set under a Receiver, being left open to the common Air. Decemb. 16. The Urine in Vacuo was not changed. The other in 10 days time seemed Turbid, and its Superficies mouldy. From this and the foregoing Experiment we may infer, that Urine contains less Air than Milk. Besides, the Efficacy of Air corrupting Urine is worth Notice. EXPERIMENT XII. May. 19 Diluted Paste. A Vessel half full of diluted Paste, which was without Leaven, being conveyed into a Receiver, before the Receiver was quite exhausted, the Paste was swollen quite to the Top of the Vessel. May 20. It swelled more, several Cavities being interspersed through it. May 22. It yielded more Air, and was much more tumid. May 23. The Receiver was separated from the Cover by the Air produced in the Receiver. The swelling of the Paste was something abated, and it was much more so in the Afternoon: It did not Taste Acid. EXPERIMENT XIII. July 20. 76. Beef in Vacuo. A Quantity of Beef being put into one exhausted Receiver; and a like Quantity into another, which was in some Measure exposed to the Air. July 21. The exhausted Receiver was filled with Air: But suspecting that some Air had got in, I shut the Beef up in another Receiver. July 22. The Mercury in 14 hours was raised 15 Inches. July 25. The Receiver was not half full of Air. July 26. The Receiver was severed from its Cover; and the Beef being again ncluded in Vacuo, sustained 10 Digits of Mercury in an hours time. July 28. The Receiver was full, and when re-exhausted, the Beef yielded a great deal of Air again in a short time. July 30. The Receiver was again filled, and being exhaust'd, the Beef yielded so much Air in an hour as was able to sustain 10 Digits of Mercury. August 1. The Receiver being again full, and the Beef Stinking, we threw it away. Hence it appears, that, Flesh yields more Air whilst it Putrifies than before, but it is otherwise with Fruits. See Exp. IX of this Article. EXPERIMENT XIV. July 18. 78. Goosberries in Vacuo. GOosberries being shut up in Vacuo; In half an hour the Mercury was raised a Digit: In an hour and half it was raised another. July 19 The Receiver was almost filled. July 20. The Receiver and its Cover being parted, a good deal of Juice ran out. July 29. The Goosberries were again included in Vacuo. July 30. In 16 hours the Mercury raised an Inch and ½. July 30. 77. They did not wholly fill the Receiver: Some time since they lost their red Colour, and inclined to a White one. It seems from hence to follow, that since after they had yielded all their Air, they underwent no change, that Air was the Cause of Corruption. EXPERIMENT XV. Aug. 23. Pears in Vacuo. PEars being included in a Receiver, with as much Air as raised the Mercury an Inch and ½. In two hours it was almost 6 Inches high. Aug. 24 It was 12 Aug. 25 It was 16 Aug. 26 It was 18 Aug. 27 It was 21 Aug. 28 It was 23 Aug. 31 It was 30 Sept. 1 It was 32 Inches high. Sept. 2 It was 35 Inches high. Sept. 3 It was 38 ⅓ Inches high. Sept. 4 It was 44 Inches high. Sept. 5 It was 45 Inches high. Sept. 6 It was 50 Inches high. Sept. 7 The height was the same; some Air getting out. Sept. 9 It was 53 ½ Inches high. Sept. 8 It was 54 ½ Inches high. Sept. 10 It was 58 Inches high. Sept. 12. Yesterday there was no Alteration: To day, as I suspected, some Air getting out, it was 53 ½. Sept. 13. Being transmited into another Receiver it was 32 ½. Sept. 16. The Receiver being opened the Pears were Rotten. EXPERIMENT XVI. From Sept. 17 to 22. Plums in Vacuo. PLums dried being enclosed in a Receiver yielded very little Air. Nou. 8. The Receiver was opened, no more Air being produced. EXPERIMENT XVII. Sept. 28. Nut-Kernels. NUt-kernels being enclosed in a Receiver. Sept. 26 It risen A little Sept. 30 It risen 2 Inches Oct. 6 It risen By degrees to 6 Inches. Oct. 15 It was 10 Digits high. Oct. 22 It was 15 Digits high. Nou. 28. It was 20 Digits high. The Kernels had neither lost their Colour nor Taste: So that Air may be procured from Fruit of an hard Consistence, without Putrefaction. ARTICLE X. Concerning the Production of Air above its wont Pressure. EXPERIMENT I. Jun. 22. Pease with a Glass full of Raisin. NEw Pease were shut up in a Receiver with a Glass full of Raisins of the Sun bruised and mixed with Water. Towards Evening the Raisins yielded Air enough to raise the Mercury 12 Digits. Jun. 23 It was 49 Digits high. Jun. 24 It was 75 Digits high. Jun. 25 It was 90 Digits high. Jun. 26 It was 90 Digits high. Jun. 28 It was 100 Digits high. The Pease turned Yellow and seemed to Sweat. Jun. 30 It was 110 July 1 It was 110 July 4 It was 124 July 7 It was 140 July 16. It remained at the same height; but the Liquor which came from the Pease got out. July 12. New Liquor was produced; The Mercury neither rose nor fell. July 13. The Liquor got out, and some Air; But the Cover being better adapted, new Liquor was produced. July. 25. The Receiver was broke in Pieces. The Pease kept their Taste, and parted from their Husks as if they had begun to boil. EXPERIMENT II. Sept. 15.76. Unripe Plums in Compressed Air. UNripe Plums being shut up with as much Air as sustained an Inch of Mercury. Sept. 16 It risen to 6 Sept. 17 It risen to 8 Sept. 18 It risen to 10 Sept. 19 It risen to 12 Sept. 20 It risen to 14 Sept. 22 It risen to 18 Sept. 23 It risen to 18 Sept. 24 It risen to 19 Sept. 26 It risen to 23 Sept. 28 It risen to 26 Octob. 1 It was 30 Octob. 4 It was 31 It was somewhat Cold. Octob. 5 It risen to 32 Octob. 7 It risen to 33 Octob. 9 It risen to 33 ½ Octob. 11 Octob. 14 It risen to 27 Octob. 15 The Cold abated. Octob. 17 It risen to 38 Octob. 19 It risen to 39 ½ Octob. 22 It risen to 41 Octob. 26 It risen to 43 Octob. 29 It risen to 45 Nou. 2 It risen to 46 Nou. 5 It risen to 47 Nou. 20 It risen to 53 The Production of Air is, in this Experiment, sometimes regular and sometime irregular. EXPERIMENT III. July 6. 76. Goosberries in Compressed Air. GOosberries included in a Receiver with as much Air as raised Mercury ½ of an Inch; in half an hour it was raised half an Inch more; in 7 hours it was raised to 5 Inches. July 7 It risen 5 July 8 It risen 3 ½ July 9 It risen 3 ¾ July 10 It risen 4 ¾ Digits high. July 11 It risen 4 Digits high. July 12 It risen 4 Digits high. July 13. The Cover was broke; and another substituted in its Place. July 14, 15, 16, 17, 18. There was no Change: The Fruit being taken out, Part was shut up in Vacuo; the rest with common Air. In four hours the Ascent of the Mercury was 4 Digits. July 19 The Mercury ascended ½ in 14 hours; but because I suspected that some Air got out, I set the Screw, and in 9 hours the Mercury risen 11 Inches. The Cover broke and the Air was lost. Hence it appears, that unfermented Goosberries contain much Air, which they more readily afforded, when the Pressure of the Air, is taken off; though when fermented they yield a great deal more in Compressed Air. EXPERIMENT IU. July 8. 76. Paste in Compressed Air. SWollen Paste being included with as much Air as raised Mercury, by the Pressure of that, lost a third Part of its humidity. Soon after it swelled again, and in half an hour raised the Mercury two Digits. The Paste continued to swell, and the Mercury in an hour was raised 2 ½. In an hour more it was raised 3 ½ and in another 4 ½. It stayed at 16 Digits. July 9 In 14 hours it was raised 21 Inches high, and stood at 37. the Screw being set to prevent Air from getting out, the Cover broke, and upon an Ingress of Air, the Paste subsided 2 Digits, tho' the Compression was less than before. In 5 hours' Space the Mercury ascended 13 Digits. But the Screw being set, the Cover broke again, so that the Air got in, and depressed the Paste again. In 4 hours the Mercury ascended 10 Digits, and the Paste risen as before; But being willing to make use of another Screw, I permitted a little Air to get out. July 10. The Paste risen again this Night, but yielded not Air. In 7 hours' time the Mercury ascended 4 Inches. July 13 A little Air was produced. July 17. The Paste being taken out, was subacid in Smell. Hence it appears, that Paste may yield Air in Compressed Air, as well as in Vacuo. The rising of the Paste seemed to depend on the Expansion of the Air in the Paste, which was depressed and overpowered by the External Air, when it was let in. EXPERIMENT V. July 13. 76. Beans shut up in a Receiver. BEANS, such as Horses eat, being shut up with Water in Vacuo, those that were bruised, seemed to swell; those which were whole, seemed unalter'd. The Mercury, July 14 rose 7 July 15 rose 5 July 16 rose 3 July 17 rose 6 July 18 rose 9 July 19 rose 1 July 20 rose 3 ½ July 21 It risen 5 ½ It risen 2 July 22 It risen 78 July 23 It risen 5 i e. 35 July 24 It risen Above the wont Pressure. July 25 The Receiver was not able to bear a greater Pressure. The Beans were very fetid, like putrified Flesh. Beans yield Air in a moderate Pressure, as well as in Vacuo, sometimes sooner, and sometimes slower. EXPERIMENT VI. July 23. Goosberries in Vacuo. GOosberries shut up in Vacuo; and in 2 hours the Mercury ascended 1 Inch. July 24 It ascended to 7 ½ July 25 It ascended to 12 July 26 It ascended to 17 July 27 It ascended to 20 July 28 It ascended to 24 ½ July 29 It ascended to 30 July 30 It ascended to 31 almost Some Air, being transmitted out of this into another Receiver, it stood at 26. July 31 The height was 35. August 1. Some Air got out, and whilst I endeavoured to stop the Receiver close, the Mercury that was raised to 39 Inches, subsided to 30 Inches. Aug. 2 The height of the Mercury was 39 Some Air being transmitted, it stood at 31. Aug. 3 The height of the Mercury was 39 Aug. 4 The height of the Mercury was 41 Aug. 5 The height of the Mercury was 43. Air transmitted it stood at 30 Aug. 6 The height of the Mercury was 43 Aug. 7 The height of the Mercury was 47 Aug. 8 The height of the Mercury was 48. Air being transmitted, it sunk to 36. Aug. 9 The height of it was 41. Aug. 10 The height of it was 47. Air being transmitmitted, it stood at 35. Aug. 11 The height of it was 38 ½ Aug. 12 The height of it was 42 The Air was drawn out, and the Mercury was 26 Inches high. Aug. 13 The height of it was 33 Aug. 14 The height of it was 36 Aug. 15 The height of it was 39 Aug. 16 The height of it was 41 ½ Aug. 17 The height was 44 Aug. 11 The height was 47 Aug. 19 The height was 50 The Air being transmitted, and the Goosberries taken out, they had lost their Colour, and almost all their Acidity. They produced Air very regularly, except a little faster, when some part had been drawn out. EXPERIMENT VII. Sept. 12. Crude Grapes. CRUDE Grapes were put into a Receiver, with as much Air as raised Mercury 3 Digits. Sept. 13 The height was 5 Sept. 14 The height was 10 Sept. 16 The height was 17 Sept. 17 The height was 19 Sept. 19 The height was 23 Sept. 20 The height was 25 Sept. 22 The height was 30 It was stopped with a Screw Sept. 23 The height was 3 ½ Sept. 24 The height was 32 Sept. 26 The height was 34 ½ Sept. 27 The height was 36 ¼ Sept. 28 The height was 36 ¼ Sept. 29 The height was 37 ¼ Sept. 30 The height was 37 ¼ Oct. 2 The height was 39 ½ Oct. 4 The height was 39 ½ Oct. 5 The height was 40 ½ Oct. 7 The height was 41 ½ Oct. 8 The height was 42 ½ Oct. 15 The height was 46 Nou. 2 The height was 54 Nou. 5 The height was 58 Jan. 10 The height was 70 There was no sensible alteration in the Gage when the Frost was most severe, tho' the Grapes and their Juice was Froze. Sept. 21. The Grapes being little altered, and the Mercury not much higher, the Receiver was opened, and the Grapes tho' more pungent, had not lost their Taste, but their Juice preserved its red Colour. Hence it appears, that Grapes yield not all their Air in a little time. EXPERIMENT VIII. August 10. 77. Pears in Vacuo. PEars cut in two being included in a Vacuum, about Evening the Mercury was raised 10 Digits. Aug. 11 It risen to 20 Aug. 13 It risen to 38 Aug. 14 It risen to 48 Aug. 15 It risen to 55 Aug. 16 It risen to 60 Aug. 17 It risen to 68 Air being Transmitted it subsided to 53 ½. Aug. 18 The height was 61 Aug. 19 The height was 64 Aug. 20 The height was 70 Aug. 21 The height was 72 Air being transmitted it stood at 61. Aug. 22 The height was 68 Aug. 23 The height was 74 Aug. 24 The height was 79 Aug. 25 The height was 81 Air being transmitted it sunk to 61. Aug. 26 The height was 56 Soem got out; being transmitted it sunk to 52. Aug. 27 The height was 60 Aug. 28 The height was 68 Aug. 29 The height was 75 Aug. 30 The height was 83 Aug. 31 The height was 88 Sept. 1 The height was 93 Sept. 2 The height was 100 Sept. 3 The height was 89 Some Air got out. Sept. 4 The height was 100 Sept. 5 The height was 100 Sept. 7 The height was 100 No Air got out. Sept. 9 The height was 107 Sept. 10 The height was 107 Air being Transmitted it sunk to 99 Sept. 11 Sept. 13 The height was 105 Oct. 8 Air got out. Pears yielded their Air by fits. ARTICLE XI. Various Experiments. EXPERIMENT I. March 16. Melted Led in a Receiver. LEad being melted in a Brass Vessel, an Inch and ½ in Diameter, it was conveyed into a Receiver, and the Air pumped out, before the Led cooled; when it was cool the Surface was concave, especially in the Middle; tho' when it cools in open Air, the Surface is generally convex, except in the Middle. The same success happened when the Experiment was made with Tin. Neither of the Metals afforded Bubbles. EXPERIMENT II. Sept. 2. A Solution of Salt in Water. A Solution of Salt in Water being conveyed into a Receiver. Sept. 15. The Salt was not Christalized. EXPERIMENT III. August 8. 76. Artificial Air. ARtificial Air from Goosberries was included in a Receiver. March 1. 7 6/ 7. No Alteration in the height of the Mercury. EXPERIMENT IU. August 8. Air weighed. A Phial which was large enough to hold 7 Ounces 5 Drachms and 3 Grains of Water, having the Air exhausted, was poised to an Aequilibrium with another weight. Upon which a Piece of a Bladder which covered it, was pierced with a Needle, and the Air getting into it, weighed 4 Grains & ½, which Weight is to the former, as 1 to 814; so that Water is 800 times heavier than Air of the same Bulk. EXPERIMENT V. Jan. 16. 77. Aqua fortis and fixed Nitre. AQua fortis and fixed Nitre, being mixed in a Receiver together, yielded much Air. March 5. The Air was not destroyed, nor the height of the Mercury altered. But Nitre was produced in Vacuo from the Mixture. EXPERIMENT VI. May 12. 76. Several Bodies in Vacuo. A Phial which had a long Neck, being so far filled with Oil, that it wrought up to the middle of its Neck, was conveyed into a Receiver; and so much Air Compressed into it, as raised the Mercury 120 Inches above the usual height. The Surface of the Oil subsided ¾ of an Inch, being condensed by Cold; which was evident, since the compressed Air being let out, the Surface risen not again. August 5. The same Experiment being made with Water, there was no sensible Alteration in the height of its Surface, though the heat might have given reason to expect some change. Jan. 14. 78. A Glass Phial being filled with Spirit of Wine, till it risen within 3 Inches of the Top of its Neck, was by the heat of my Hands, caused to rife to the top of the Vessel: Which being then Inverted into a Vessel full of Mercury, and my Hands removed, the Cold Spirit admitted 3 Inches of Mercury into its Neck; yet being conveyed into a Receiver, and so much Air compressed into it, as raised 90 Digits of Mercury, the Spirit was not in the least condensed by compression, though Cold had such a considerable effect on it. When the Receiver was opened there was no appearance of Bubbles in the Spirit of Wine. It would be worth while to consider, why Cold should have such a considerable Effect in condensing Spirit; and why it cannot be condensed by Compression. EXPERIMENT VII. May 12. 76. Spirit of Wine and Oil of Turpentine. SOme Spirit of Wine contained in a Glass Vessel, with some drops of Oil of Turpentine upon it, were briskly moved about, till the Receiver being exhausted, they stuck to several Bubbles which risen out of the Spirit of Wine, and were by them carried to the sides of the Vessel; where they were kept, except 2 Drops, which the Bubbles left behind upon the Surface of the Spirit; which, whilst the Receiver was exhausting, continued their Motion, but in a little time after, were wholly at rest. Yet upon a Re-ingress of Air, they for a little while renewed their Motion again. The same Experiment being repeated with Spirit of Wine and Oil of Turpentine, wholly freed from Air; there was neither any Ebullition, nor an appearance of Bubbles; yet the Drops of Oil moved in Vacuo after the same Manner as in open Air. Hence it appears, that the Motion of the Parts of Oil, depend not in a Dissolution in Vacuo; since all Dissolutions are companyed with a production of Bubbles. EXPERIMENT VIII. May 19 76. Radishes in a Receiver with Claret. HAving cut two Radishes transversly, and suspended them all Night in Vacuo, over a Vessel of Claret, the small End of one being downwards, and the other in a contrary Posture; all being freed of their Air, the next Day I freed two other Radishes from their thick Skin, and cutting them transversly, suspended them over the Wine, as the others, in Vacuo; upon which, immersing them all in the Wine, they emitted Bubbles considerably; especially, those that had been longest in the Receiver. From this Experiment we may urge, that Bubbles are formed of Particles of Air contained in Water; and the Reason why those Radishes yielded most Air; whose Skins were not pulled off, is, because those Skins are full of Canals and Pores, to contain Air, in for the forming of Bubbles. The Liquor ascended equally in all the Radishes, notwithstanding their Postures. EXPERIMENT IX. May. 4. A small Tube immersed in Water. A Small Glass Tube open at both Ends, being immersed in Water, the Water in Vacuo, ascended as high as it usually does in common Air; but in a little time it was raised higher, by Bubbles of Water, which divided and intercepted the Cylinder of Water in 3 several places; besides, several Bubbles of Water passed out at that End of the Tube which was immersed. One End of this Tube being Hermetically sealed up, the Experiment succeeded after the same manner, as when it was open; but in the open Air, the Water ascended not. One thing in this Experiment was very Remarkable, viz. That the Water suspended in the Tube, yielded no Bubbles, but only at the Bottom of the Tube; nor did the Cylinder of Water even at the Bottom yield Bubbles, when it was raised above the Surface of the Water which it was before immersed in. May. 5. The Experiment was repeated; but before the End of the Tube was immersed in Water, a Drop, which ran over the Superior Aperture of the Receiver, fell down to the open End of the Tube, and was raised two Lines in the Cavity of the Pipe: No Bubbles were formed in half an hour, till the Tube was immersed in Water, and then successively they risen one after another. In trying this Experiment, several times I observed, that though, whilst the Tube was immersed, several Bubbles appeared about the End of it, yet when it was raised above the Surface of the Water, none were to be seen. May 6. The Experiment was tried with an Infusion of Nephritick Wood; in which the Success was alike, except that in the Infusion, when the Bubbles were small, they ascended to the Top of the Liquor, which is an Argument of its Thinness, and that it hath no Viscocity. May 10. I repeated the same Experiment, with a Mixture of Spirit of Wine, and an Oil made per Deliquium; In which nothing was to be observed different from the former, but that the Liquor ascended not so high. From these Experiments it may probably be inferred, That the Formation of Bubbles in the Extremity of the Tube, depends on aerial Particles, which swim in the Water, and meeting with some Impediment at their End, are kept there, till new ones joining with them, form Bubbles. EXPERIMENT X. July 18. 76. Beans with Water in an Iron Tube. BEANS, such as Horses eat, being shut up with Water in an Iron Tube 2 days ago, to day seemed unalter'd; but the Stopple of the Tube being pulled back, Air and Water broke out; which Eruption was succeeded by a bubbling Noise, which continued above an hour. July 25. The Iron Tube was opened a second time, and a bubbling Noise succeeded as before. Whence it appears, that Beans contain Air, which cannot discharge itself in a Compression, till that Compression is removed. EXPERIMENT XI. March 4. 77. Spirit of Sal Armoniac and Copper. A Glass half full of Spirit of Sal Armoniac, being included in Vacuo, with Filings of Copper in it, in 15 Minutes it was tinged with a diluted Blue, which, upon an Ingress of Air, in 3 Minutes became vivid and thick. April 4. The Liquor having been enclosed in Vacuo, had almost lost its Colour, which it regained when the Air was let in again. EXPERIMENT XII. May 8. Oil per Deliquium with Spirit of Wine. OIL made per Deliquium, being shut up in a Receiver, with Spirit of Wine swimming upon it; when the Air began to be exhausted, great Bubbles risen from the Spirit, and small ones from the Oil; but in an hour, the Oil afforded Bubbles large enough to fill the whole Diameter of the Pipe in their Ascent, and an hour after that, they broke out so violently, as to strike against the Top of the Receiver. May 9 The Experiment being repeated in a Vessel, which was longer and narrower, I observed, that the Bubbles which risen from the Oil, were not very large, till ¼ of an Inch above the Surface of it, and then they were suddenly expanded. EXPERIMENT XIII. May 3. 76. Aq. Fort. and Spirit of Wine. A Mixture of Aqua Fortis and Spirit of Wine, being divided into three Parts, and each of those included in a distinct Vessel with a piece of Iron, one of them was included in Vacuo; upon which, several considerable Ebullitions succeeded. The Liquor when taken out, was black and Turbid; tho' in the other two, it was not altered in Colour, but only a black Powder was settled in the Bottom. Wherefore one of those being included in Vacuo, after Ebullitions, less violent than those in the Vessel first included, the Liquor in a quarter of an hours time, being taken out, was almost as black and turbid, as that first put into the Receiver: That in the open Air, was not much altered. May 4. The Liquors shut up in the Receivers, appeared clear and green; But that in the open Air, bubbled more than the day before, and was of a red Colour: And all three being shut up in Vacuo, the red Liquor afforded larger Bubbles. Hence it appears, that Spirit of Wine promotes Ebullition in Vacuo. EXPERIMENT XIV. Jan. 21. 78. Spirit of Sal Armoniac with Filings of Copper. A Glass half full of Spir. Sal Armon. with Filings of Copper, stopped with a Leather Stopple, was put into a Receiver, with unfermented Paste. Jan. 22. The Air yielded by the Paste, penetrated the Leather, which is impervious to common Air, which appeared by the Tincture it gave the Liquor. Jan. 25. The Liquor had almost lost its Colour; so that the Particles of Artificial Air are so minute, as to penetrate Pores which common Air cannot. Feb. 2. The Glass being shut up in a Receiver, which admitted Air so gradually, as to be filled in 24 hours, the Liquor still remained Colourless. Feb. 15. The Glass being again shut up in Vacuo, with Paste, the Air afforded by it, did not as before, penetrate the Leather; nor was the Liquor in the least tinged by it. EXPERIMENT XV. April 2. 78. HAving put a Shrew-Mouse into the Engine described, A Shrew-Mouse in Vacuo. for the Filtration of Air through Water; when the Pump was stirred, and the Air began to penetrate the Water, it was a little better; but could not recover. Apr. 12. The Experiment was repeated with a weakly Mouse, that had been kept fasting a long time; the Success was the same as in the last Experiment; for the Mouse being taken out before it was dead, could not recover in the free Air. EXPERIMENT XVI. May 2. 78. SIX Weeks ago, Spawn of Frogs in Vacuo, etc. Spawn of Frogs being included in common Air, in Vacuo, and in another Receiver with compressed Air, which sustained 60 Digits above the ordinary height. The Mercury in Vacuo, in 15 days was raised 1 Inch. The Spawn in common Air, was corrupt and blackish; that in the compressed Air remained unalter'd. A Month after, the Spawn in Vacuo was turned into Water, except the black Spots; but had not altered its Colour. That in the common Air was very black; That in the compressed Air began to be reddish; which Colour sensibly increased. May 22. That in the common Air had lost its Colour. June 23. That in the compressed Air had acquired a Greenness. Octob. 15. That in Vacuo was exhaled out of its Vessel, and remained in the Receiver in the Form of Water: That in the common Air was void of Colour; and that in the compressed Air was still red. EXPERIMENT XVII. May 9 78. AN Orange having been divided, Oranges in Vacuo. and included in two Receivers, in which was left an equal Vacuity; the Capacity of the larger being so far filled with Water, as it was bigger than the Cavity of the other, I observed, that that which was shut up with Water, was four times more mouldy than the other. The same Experiment was repeated, the third part of the Cavity of one Receiver being filled with Water, yet the Orange was not touched by it. June 15. Neither of the Pieces of the Orange was mouldy, and the same Experiment being again repeated, neither Piece was mouldy in a Month's time. The Difference seems to be the Effect of some Disposition in the Air. EXPERIMENT XVIII. June 1. 78. A Small Glass Tube, Venice Turpentine in a Wind-Gun. half full of Venice Turpentine, being put into the Wind-Gun, as soon as the Air was compressed into a tenth Part of the Space it possessed before; The Leather which covered the Elliptic Hole was driven out. The Tube being taken out, I perceived several Bubbles in the Top of the Turpentine, which I supposed, had been pressed into it when the Cavity of the Gun had Air compressed in it; Therefore placing the Tube again in the Gun, I caused the Air to be condensed to 15 times as little compass. June 3. The Turpentine being taken out, was free from Bubbles, but by degrees, a great many were formed in it. June 4. Having freed Turpentine from its Air, and poured Water upon it, I shut up all in the Wind-Gun. June 8. At the first sight, both the Water and Turpentine were free from Bubbles; but soon after they appeared and ascended in the Turpentine, almost from the Bottom: So that the Air that formed these Bubbles penetrated the Water and most of the Turpentine. EXPERIMENT XIX. Aug. 11. 78. WHEN Spirit of Sal Armoniac was cleared of its Bubbles, Filings of Copper and Sp. Sal Armon. in Vacuo. I mixed Filings of Copper with it in Vacuo; upon which, it yielded several Bubbles; they did not yield Air, but destroyed what was contained there before; The Liquor was green and turbid. Decemb. 5. The Spirit was for the greatest part got out of the Vessel, and condensed in the Receiver; that which continued in the Vessel, was as clear as Water. The Mercury was wholly driven out of the Gage; whence it was reasonable to suppose, that the Air was gradually consumed in the Receiver. EXPERIMENT XX. Septemb. 2. 78. A Cylinder of Tin, and another of Lead, Mercury raised in a Tube in Vacuo, etc. being immersed in Vacuo in Mercury, and two others in Mercury exposed to common Air. Sept. 6. The Mercury in the Tin Cylinder in Vacuo, was raised 4 Inches and a half. The Pipe being cut transversly, half of that Space above the Mercury it was immersed in, and in another place an Inch above the Surface of the Mercury, the Amalgama had penetrated into the Metal half a Line above, and a whole one below. The Mercury in the Lead Pipe had not sensibly penetrated into that Metal, except where it was immersed: It was raised in it 2 ½. Sept. 7. The Mercury had ascended 5 Digits in the Tin Pipe, which was exposed to the Air. Sept. 10. The same Cylinder continuing in the Mercury, was besmeared up to the very Top, 6 Inches above the Surface of the stagnant Mercury, which had penetrated the Tube the deeper, by how much the nearer the stagnant Mercury, so that near the Surface it had penetrated 3 Lines deep. The Mercury was not raised above 3 Digits and a half in the Lead Pipe, nor had it made any sensible Penetration: So that the Pressure of the Air contributes little to the Ascent of Mercury into Metals. EXPERIMENT XXI. Decemb. 12. 78. THE Head of a Whiting being cut off, A Whiting in Vacuo. and divided into 5 parts, one of them was shut up in Vacuo; another in common Air, another in compressed Air, which sustained 50 Digits above the usual height. The fourth was included with Air from Paste, the last piece was exposed to open Air. Decemb. 15. That in the open Air, in the Morning began to shine; and in the Evening, yielded a Light more vivid. Decemb. 16. It gave over shining till Evening. Dec. 17. It shined a little. Dec. 18. at Night it shone a little. Dec. 20. It continued to shine. Dec. 22. It ceased. Dec. 23. That included in common Air, began to shine. The 24. It did not. Jan. 26. 79. None of them shined. ARTICLE XII. Artificial Air destroyed. EXPERIMENT I. August 3. 77. ARtificial Air of Cherries being transmitted into a Receiver full of common Air, Artificial Air of Cherries destroyed. till the Mercury was raised 25 Inches above its usual height. Aug. 4 It sunk to 23 Aug. 6 It sunk to 20 Aug. 7 Aug. 8 a little Aug. 10 to 19 ½ EXPERIMENT II. May 26. 76. Artificial Air generated and destroyed. SIX Grains of Sal Armon. being let fall into a sufficient Quantity of Oil of Vitriol in Vacuo; there followed a great Ebullition, so that the Mercury risen to it's usual height, but presently subsided again. May 27. The same Experiment being tried, with this difference, viz. that the Salt was kept 10 hours in Vacuo, before it was dropped into the Oil; the Success was, that it was 7 or 8 hours before the Air generated by the Ebullition, was destroyed. May 29. The Salt being not mixed till after 24 hours, the Ebullition and Quantity of Air generated, were less, and more slowly produced; and it was observable, before the Ingredients were mixed, that the Mercury rather subsided in the Gage, as if some Air had been drawn out. July 8. Oil of Vitriol being included with a fifth Part of common Air, raised the Mercury a little, and kept it up 24 hours. From whence it appears, that Artificial Air may be destroyed. ARTICLE XIII. Experiments concerning the different Celerity of Air produced in Vacuo, or in Common Air. EXPERIMENT I. Common Air. July 1.0 77. Air from sour Paste. SOwrish Paste being included in a Receiver, In an hour the Mercury was raised an Inch; in 7 hours 6 Digits. July 11 The height was 11 July 12 The height was 24 July 13 The height was 30 July 14 The height was Sensibly greater. July 15 It ascended a little. and was 38 Inches high. July 19 It yielded no more Air. Vacuum. July 10. 76. A less Quantity being enclosed in Vacuo, in an hour the Mercury ascended 2 Inches, In 7, it was raised to the Top of a short Gage. July 19 The Cover was not separated from its Receiver; but the Paste being fired by a Burning-Glass, it's Superficies was tinged yellow by the Fumes, which after their Ascent fell upon it, so much Air was produced, that the Cover was easily removed from the Receiver. EXPERIMENT II. Common Air. August 20. 76. From Paste 24 hours old. PASTE 24 hours old, being included with as much Air as raised Mercury 4 Digits and ½ above its usual height. In 6 hours, it was raised to 8 Inches. Aug. 21 It risen 4 ½ Aug. 22 It risen 1 Aug. 23 It risen ½ Aug. 26 It risen ½ Aug. 27 It ascended not. Aug. 29 It smelled subacid. Vacuum. Aug. 20. Paste being enclosed in Vacuo, the Mercury was presently raised 2 Inches. Aug. 21 It risen 5 Aug. 22 It risen 3 Aug. 23 It risen 1 Aug. 26 It risen 2 in 3 days. Aug. 27 It risen 0 Aug. 28 The Paste was taken out. Hence it appears, that sometimes Air is more easily produced in Vacuo, than common Air. EXPERIMENT III. Vacuum. Septemb. 4. 77. From filbert Kernels. filbert Kernels were enclosed in common Air. Sept. 5 The height was 5 Sept. 6 The height was 10 Sept. 7 The height was 10 Sept. 8 The height was 12 Sept. 9 The height was 15 Sept. 11 The height was 18 Sept. 12 It was 23 Sept. 13 It was 27 Sept. 14 It was 29 Sept. 15 It was a little more. Sept. 17 It was 30 Sept. 18. Some Air got out; several Bubbles appearing in the Turpentine, which guarded the Joints of the Receiver. Common Air. Sept. 4. In the Afternoon the Air seemed to be diminished. Sept. 5 It was almost ½ Sept. 6 It was the same Sept. 7 It was 1 Inch. Sept. 8 No Alteration. Sept. 18 No Alteration. EXPERIMENT IU. Septemb. 15. 77. EIGHT Ounces of Raisins of the Sun, bruised and diluted with Water, being included in a Receiver, large enough to hold 22 Ounces of Water. Sept. 16 The height was 6 Sept. 17 The height was 10 Sept. 18 The height was 15 Sept. 19 Sept. 20 It was 29 Sept. 21 The Receiver forced from the Cover. Sept. 24. Some Raisins being taken out, the rest were shut up in Vacuo. Sept. 25. The Receiver was severed from its Cover. Sept. 15. 77. The same Ingredients being shut up in common Air. Sept. 16 The height was ½ Sept. 17 The height was 1 ½ Sept. 18 The height was 3 Sept. 19 The height was 5 Sept. 20 The height was 7 Sept. 21 The height was 9 Sept. 22 The height was 11 Sept. 23 The height was 12 Sept. 24 The height was 15 When the Air broke out, several Bubbles risen from the Raisins: Hence it appears, that Air is more easily generated sometimes in Vacuo, than in common Air. EXPERIMENT V. Vacuum. Feb. 17.77. Onions in Vacuo. THREE Onions being enclosed in Vacuo. Feb. 19 The Ascent was 1 Feb. 21 The Ascent was 1 Feb. 25 The Ascent was 9 May 4 They were not altered. May 18 They were not altered. Jun. 19 The onions rotten. Rarified Air. Feb. 17. Three Onions were enclosed in Air, so far rarified, that it sustained only 10 Digits of Mercury. Feb. 19 The Mercury ascended not. 21. They had acquired a Mouldiness. 25. The Mercury ascended 7 Digits. May 4. No Alteration in the Onions. 18. No Alteration in the Onions, but the Receiver was forced from the Cover. Common Air. Feb. 17. Three Onions were included in a Receiver, not exactly shut. Feb. 21. They were not mouldy; but budded. 25. They shot forth their Roots. May 4. They began to be Mouldy. This Experiment shows, that some Bodies yield Air as well in rarified Air as in Vacuo. As also that Vegetation is promoted by Air. It is here likewise worth our Notice, that whilst the Onions shot forth, they did not grow Mouldy ARTICLE XIV. EXPERIMENT I. Bruised Fruits. August 23. 77. Bruised Pears in Vacuo. Bruised Pears being included in an exhausted Receiver. Aug. 25 The height was 5 Aug. 26 The height was 10 Aug. 27 The height was 14 Aug. 28 The height was 18 Aug. 29 The height was 21 Aug. 30 The height was 25 Aug. 31 The height was 28 Sept. 1 The height was 30 Sept. 2. Receiver was separated from the Cover. Whole Fruit. August 23. Whole Fruit. The same Quantity of Pears being proportionably included in a Receiver. Aug. 25 The height was 11 Aug. 26 The height was 17 Aug. 27 The height was 25 Aug. 28 It was 28 Aug. 29 It was 33 Aug. 30 The Receiver was forced from its Cover. Hence it seems, that entire Fruit yielded Air sooner than Bruised ones. EXPERIMENT II. August 24. Whole Apples in Vacuo. WHole Apples being included in a Receiver exhausted. Aug. 25 It was 5 Aug. 26 It was 9 Aug. 27 It was 12 Aug. 28 It was 15 Aug. 29 It was 19 Aug. 30 It was 25 Aug. 31 It was 28 Sept. 1 It was 29 Sept. 2 It was 30 Sept. 3 The Receiver severed from the Cover. August 24. An equal Quantity of bruised Fruit being put into a Receiver. Aug. 25 It was 1 Aug. 26 It was 3 Aug. 27 It was 4 Sept. 3 The same. Sept. 25 The same. This Experiment is a Confirmation of the Inference drawn from the last. EXPERIMENT III. August 25. 77. Bruised Grapes were shut up in Vacuo. Bruised Grapes in Vacuo. Aug. 36 It was 1 Aug. 27 It was 2 Aug. 28 It was 2 ½ Aug. 29 2 ½ Sept. 15 2 ½ August 25. 77. Unripe Grapes whole were shut up in a Receiver. Aug. 26 It was 3 Aug. 27 It was 5 Aug. 28 It was 7 Aug. 29 It was 10 Aug. 30 It was 12 Aug. 31 It was 13 Sept. 1 It was 15 Sept. 2 It was 16 Sept. 3 It was 18 Sept. 4 It was 18 Sept. 5. They began to be Yellow. Sept. 7 They grew Yellow; the Mercury was 18 Inches. Sept. 15 it was 20. This is a further Confirmation of the former Experiment. EXPERIMENT IU. Sept. 10. 77. TWO Ounces of ripe Grapes being included in a Receiver capable of holding 10 Ounces. Ripes Grapes. Sept. 11 It was 6 Sept. 12 It was 9 Sept. 13 It was 12 Sept. 14 It was 15 Sept. 15 It was 20 Sept. 16 It was 25 Sept. 17 It was 28 Sept. 18 It was 30 The Grapes unalter'd. Sept. 19 It was 30 Sept. 20 Grapes a little riper. Sept. 21 The Receiver was forced from the Cover. Sept. 22 The Grapes beginning to Rot, were shut up in another Receiver. Sept. 23 It was 5 Sept. 24 It was 9 Sept. 25 It was 14 Sept. 26 It was 17 Sept. 27 It was 20 Sept. 29 It was 27 Sept. 30 It was 28 Oct. 10 The Receiver forced from the Cover. The Grapes seemed rotten; but preserved their Firmness Sept. 10. 77. The same Quantity of bruised Grapes being included in a Receiver of the same Size. Sept. 11 It was 4 Sept. 12 It was 7 Sept. 13 It was 10 Sept. 14 It was 12 Sept. 15 It was 15 Sept. 16 It was 18 Sept. 17 It was 20 Sept. 18 It was 25 Sept. 19 A good Quantity of the Juice was Spilt, the Receiver being severed from the Cover. Sept. 20. The same Grapes were shut up with as much Air as raised the Mercury 3 Inches. Sept. 21. The Receiver was separated from the Cover; and the Grapes enclosed in another Receiver with common Air. Sept. 22. The Mercury was 11 Inches high. Sept. 23 It was 19 Sept. 24 It was 19 Sept. 30 It was 20 Oct. 3 Being taken out they were bitter. Ripe Grapes yield more Air when bruised, than unbruised. EXPERIMENT V. Nou. 19 78. A Sound and a bruised Apple, Sound and bruised Apples in Receivers. being each put into a distinct Vessel; Another bruised one was put into a third; which was so adapted to it, that when the Receiver was exhausted, the Air formed in the bruised Apple expanding itself, squeezed out the Juice. Nou. 22. In the first Receiver the Mercury was 5: In the second 3: In the third 0. Nou. 23. In the 1st 7 Inches: In the others no Alteration. Decemb. 7. In the 1st 11: No Alteration in the others. Jan. 23. The first separated from the Cover. May 20. 79. The third separated from the Cover: In the second no Air produced. The Reason why bruised Fruits yield most Air in Vacuo, seems to be, because they there have more Liberty to expand their Parts. ARTICLE XV. Air is sometimes found unfit to produce Mouldiness. EXPERIMENT I. July 12. 78. ROses being included in two Receivers, Roses in Common and Compressed Air. and as much Air with one of them as sustained 60 Digits of Mercury. August 2. Those in Common Air turned Yellow, the others retained their Colour. Feb. 10. 79. Those in the Compressed Air were unalter'd. This compared with Exp. IU. Art. iv shows, that several times the Air is so different, as sometimes to hinder and sometimes to promote Corruption. EXPERIMENT II. May 22. Tulips and Lark-Spurs. TUlips and Larks-spurs being shut up in two Receivers, and as much Air compressed in One as sustained 60 Inches of Mercury 15 Days ago. In five days some of the Tulips in the Common Air that were cut, seemed Mouldy. To day the other part seemed Mouldy. The Flowers seemed as fresh as when first put in; but those in Compressed Air were more moist. June 22. No more Mouldy: This Experiment compared with the same made the Year before, confirms the Inference drawn from the foregoing. ARTICLE XVI. Experiments concerning the Change of Weight, made in the Beams of the Sun, even in Vessels sealed Hermetically. EXPERIMENT I. Sept. 4. 78. Minium exposed to the Sun Beams. A Drachm of Minium being exposed to the Sun Beams, concentered by a burning, Glass lost ¼ part of a Grain. EXPERIMENT II. Sept. 6. Calcined Coral exposed to the Sun Beams. Calcined Coral being exposed to the Beams of the Sun in a Glass hermetically sealed, became whiter. Sept. 10. In two hours, the Glass being weighed, it from the first had lost 1/1● of a Grain. EXPERIMENT I. May 23. Calx of Tin in a Glass Hermetically Sealed. CAlx of Tin included in a Glass hermetically Sealed, lost 1/64 part of a Grain, by the Effects of the Sun Beams concentred by a burning Glass. May 29. The Experiment being tried with Minium, it lost 1/32 part of a Grain. May 30. Being about to repeat the Experiment, the Glass flew in Pieces. June 6. The same Experiment being tried with Minium it lost 1/64 part of a Grain. Upon a second trial the Glass broke. July 15. The Sun had no effects on Coals of Wood June 20. The Sulphur Vive tho' it melted and fumed, lost none of its Weight. August 1. The same Experiment being repeated it lost no Weight. ARTICLE XVII. The Preservation of Bodies in Compressed Liquors. EXPERIMENT I. Aug. 3. 78. An Apricock in Water. AN Apricock was shut up in one Receiver full of Raisins of the Sun stoned; Another being conveyed into a Second, so that it neither touched the Water nor Raisins. Sept. 10. The Apricock enclosed in the Water being taken out, bubbled whilst the Air made its way out. The Apricocks had a pleasant Relish, but the Raisins had lost their Taste. Feb. 10. 78. The other Apricock only seemed to have lost its Firmness. Some Fruits may reserve their Taste in an Infusion of Raisins of the Sun, if the Vessel will bear a great Compression of Air. EXPERIMENT II. Sept. 17 78. Peaches included in Artificial Air. PEACHES being included in 2 Receivers, with an Infusion of Raisins. Sept. 11. The Air generated in one Receiver, forced out some of the Air. Sept. 25. More of the Liquor was forced out, so that a fifth part seemed empty; but the Screw being set, it was preserved. Sept. 26. The same Receiver leaked again. Nou. 27. The Receiver being opened, whilst the Air made its way out, the Peaches bubbled: The yellow sort were soft, but preserved their Taste; the other sort reserved its Firmness. The Liquor was very grateful and pleasant. Decemb. 28. The other Receiver being opened, tho' before it seemed unalter'd, yet both the Liquor and Peaches bubbled. One side was soft, the other hard: It's Taste was pleasant, but something sharp. So that Liquors may acquire a Sourness, tho' no Spirits evaporate. EXPERIMENT III. Sept. 20. Peaches and crude Grapes. PEACHES and unripe Grapes, being included in two Receivers, in one of which was Apples bruised to a Pulp; In the other, an Infusion of Raisins of the Sun. Sept. 25. That in which the Raisins were had, forced half its Liquor out, and raised the Mercury 100 Inches, the Receiver being opened, whilst the Air got out, the Peach turned as soft as a Pultis; the Taste of it was pleasant. The other Receiver was unalter'd. Another Peach was shut up with an Infusion of Raisins of the Sun. Sept. 26. The Mercury was 30 Digits higher than usual. Sept. 27. It was 72. Sept. 28. It was 90. Liquor got out. Sept. 30. It was at a stand: the Liquor was all gone. Octob. 1. The Receiver was opened, and the Peach tho' soft, tasted pleasant. Octob. 3. The Receiver in which the Apples were contained being open, all things were much fermented; the Juice of the Apples having got out, the Peach tho' soft, tasted pleasant. Fruit cannot long be preserved in the Pulp of Apples, they yield so much Air. EXPERIMENT IU. Sept. 23. 78. Pears with the Pulp of Apples. PEACHES and crude Grapes being included in one Receiver with the Pulp of Apples, and in another with unripe Grapes bruised. Octob. 1. That which contained the Apples was unalter'd: But the other had lost its wind; one of the Peaches had lost its Firmness, both of them retained a grateful Taste. Feb. 5. 79. That which contained the Apples, seemed unalter'd; the Pulp and Peaches tasted grateful, but a little too pungent; when the Receiver was opened, there happened a very great Ebullition. EXPERIMENT V. Sept. 25. 78. Pears with the Pulp of Apples. TWO Butter Pears were shut up in a Receiver with Pulp of Apples. Sept. 26. The height of the Mercury was unalter'd. Octob. 5 It was 16 Octob. 6 It was 16 † Octob. 12 It was 16 † Octob. 29. It subsided. Octob. 26. The Receiver was cracked One of the Pears began to rot, the rest, as well as the Apples, tasted well. EXPERIMENT VI. Octob. 1. 78. PEACHES being included with Pulp of Apples in one Receiver, and unripe Grapes bruised in another. Octob. 5. Wine got out. The Mercury was 64. Digits high. Octob. 6. Wine ran out. It was 70 Inches high. Oct. 8. All the Wine ran out: It was 86 high. Oct. 12. 86. Oct. 18. 86. The other Receiver which contained Pulp of Apples, for those five Days, had lost some Juice. Decemb. 4 The Receiver which contained the Apples being opened, several Bubbles broke out, with a considerable Noise; The Peach was soft and pungent. Jun. 28. 79. The Mercury in the other Receiver, stayed at the same height. The Peaches emitted several Bubbles, being wrinkled and a little altered in Colour; their Taste was very pungent, and a little acid. EXPERIMENT VII. Octob. 4. 78. Peaches with Wine and Beer. PEACHES being shut in one Receiver with Wine; In another with Beer hopped; and in another with Beer without Hops. Octob. 5. The Mercury in the last was 15 Digits high. In the second, 10. In the first, 9 Octob. 6. In the last. 25 Inches. In the second, 15. In the first, 20. Octob. 8. In the last, 35. Second, 15. First, 20. Octob. 12. In the last, 63. Second, 15. First, 28. Oct. 15. In the last, 81. Second, 15. First, 30. Oct. 16. No Alteration at all. 18. It descended a little in all. 22. The Ascent in the Wine answered the Degrees of Heat and Cold. Octob. 24. In the last, it was 96 Digits high. Second, 15. First, 30. Oct. 30. In the last, 115. Second, 29. First, 30. Nou. 3. In the last, 117. Second, 20, First, 30. Oct. 6. In the last, 120. Second 31. First, 31. Oct. 11. In the last, 105. Second, 31. First, 28. Cold Wether. Nou. 16. The Peach which was lowest in the middle Receiver, risen up to the Top; the others remained at the Bottom. Nou. 25. In the last, 140. The second, 47. First, 32. Nou. 28. In the last, 96. Second, 36. First, 28. very cold Wether. Decemb. 13. In the last, 96. Second, 47. First, 33. In the first, the Peach was firm, and well coloured; it had borrowed a Taste from the Wine; which might be made grateful with Sugar. The Wine was very palatable. Decemb. 30. In the last, 96 Digits. Second, 47. The Peaches in the last when it was opened, risen up to the Top, and bubbled; The Taste, which they had got from the Sugar, was made pleasant with it. Hence it appears, that fermented Liquors may preserve Fruit. EXPERIMENT VIII. Sept. 5. 78. ONE Peach whole, and another cut, was included with old Wine in a Receiver. Nou. 20. Some of the Wine ran out: Nou. 30. A third part was lost. Decemb. 8. The Wine was almost lost, but what remained was pleasant; the Peaches were much fermented, and a grateful Taste. This compared with the first Receiver in former Exp. shows, that Wine hinders Fermentation, if in a sufficient Quantity; but here the Peaches took up too much Room. EXPERIMENT IX. Octob. 11. 78. A Whole Peach, and another cut, was included in hopped and fermented Beer. Octob. 12 It was 3 Octob. 15 It was 15 Octob. 16 It was 15 Octob. 18 It was 12 very cold. Octob. 20 It was 12 Octob. 22 It was 12 x Warmer. Nou. 2 It was 20 Nou. 3 It was Lower, cold. Nou. 6 It was 28 hotter. Nou. 8 It was 33 Nou. 11 It was 40 Nou. 12 It was 40 Beer got out. Nou. 16 It was 46 Nou. 19 It was 43 Beer lost. Nou. 20 Beer lost. Nou. 23 It was almost all lost. The Receiver being opened, the Peaches were soft, yet of a grateful Taste. This Exper. compared with the second Receiver, Exp. VII. show that Beer in a sufficient Quantity, hinders the Generation of Air, and Fermentation of Peaches, but here the Peaches took up too much Room. EXPERIMENT X. Octob. 19 78. RAW Beef being shut up with stolen Beer, Beef with stolen Beer. compressed till the Mercury risen 60 Digits above its usual height. In another it was shut up with Beer uncompressed: And in a third, the Receiver was filled with common Air. Octob. 20. In the first it sunk 40 Digits. In the second, a little. In the third, it ascended a little. Octob. 26. In the first, it ascended and descended irregularly: It ascended slowly in the second. In the third it was at a stand. Oct. 27. A Piece left in the Air, began to smell ill: In the second and third, the Mercury ascended: In the first it descended. Nou. 3. In the second, it was 20; in the third, 10 Digits high. Nou. 5. The two first did not stink, but the Flesh had got a Taste from it; and being boiled in it, was tender. That included with common Air, stunk. But the same piece of Beef being shut up again with Air. Nou. 6. Mercury was raised 3 Digits. Nou. 11. 8. Nou. 25. 20 Digits. The Flesh stunk. Hence it appears, that Beer may preserve Beef, when compressed for some time. EXPERIMENT XI. Nou. 12. BEEF was shut up with Water, Beef with Water and Salt. and a fortieth Part of Salt, in one Receiver; In another with Salt Water, compressed till the Mercury was raised 15 Digits above its usual height. In a third, Flesh and Air was only enclosed. Nou. 13. Mercury descended in all; especially where the compressed Water was. Nou. 18. In that which contained compressed Water, it almost risen to it's former height. A piece of the same Beef exposed to the Air, began to smell ill. Nou. 23. Air was generated in all; The Mercury in the second was 20 Digits, having descended 3. In the other two, it was about 16. In the first the Flesh was not corrupted. Nou. 30. The Flesh included with Salt, did not stink; but when boiled, was tender and pleasant. Decemb. 6. The Mercury in that which contained the compressed Air was 25 Digits: The Flesh was strong scented, but did not stink. That included in Vacuo, bubbled when the Receiver was opened, and in an hours time, yielded Air enough to sustain 3 or 4 Digits of Mercury. The Receiver which contained it, being immersed in hot Water, the Liquor bubbled much, tho' the Water it was immersed in, did not boil; the Receiver was soon full of Air, and then, tho' it was immersed in boiling Water, the Liquor did not bubble. The Flesh was pleasant and tender. So that Water as well as Beer may help to preserve Flesh. EXPERIMENT. XII. Nou. 29. 78. OYsters were shut in one Receiver without their Shells; Oysters. In another they were shut up in their Shells with common Air, and in a Third with Salt-water. These three being closed up with Screws, 3 Oysters in their Shells, and 8 taken out were shut up in Vacuo; where it was observable, that when the Air was exhausted, those which were without their Shells emitted large Bubbles, one of the others opened the Shell. Nou. 30. The Mercury in Vacuo ascended a little, but in those 3 which were stopped with Screws it descended rather. Decemb. 4. The Wether growing warmer, the Mercury in the first Receiver was 7 Digits. In the Second, 0. In the Third, 3. In the Fourth 3. Dec. 5. In the First 20. In the Second, 1. In the Third 3. In the Fourth 5. Dec. 7. In the First the Height of the Mercury was 30. In the Second 1 Digit. In the Third 3. In the Fourth 8. Other Oysters left in the open Air began to Smell ill. Dec. 9 In the First it was 30; In the Fourth 11. In the Rest no Change. Dec. 13. In the Fourth it was 14 Inches High. Dec. 20. In the First it was 46. In the Fourth 24. No alteration in the others. Dec. 21. In the 1st. 52. In the 4 th'. 25. No alteration in the others. Dec. 22. In the 1st. 60. In 4 th'. 27. No alteration in the Rest. Dec. 27. In the 4 th'. 29. No alteration in the Rest. Jan. 7. 79. The Oysters in the Third Receiver had Coloured the Water black. Jan. 25. Some Bubbles were form in the Turpentine, about the Commissure of the Receiver and Cover, of that which was exhausted; the Height of the Mercury was not altered, but the Oysters being taken out Stunk: Those in the other Receivers Stunk, and were turned to a viscous Jelly. From this Experiment it seems to follow, that Fishes yield not so much Air as Flesh; yet they will Corrupt tho' not affected by the outward Air. EXPERIMENT XIII. Nou. 29. 78. A Vessel of fresh Butter. A Glass Vessel filled with fresh Butter, being conveyed into a Receiver with a Mercurial Gage. Nou. 30. The Butter being in the Night condensed by Cold, the Mercury sunk a little. Decemb. 2. The Cold increasing, the Mercury sunk sensibly. Decemb. 5. The Cold growing more remiss, the Mercury ascended almost to its former Height; some of the same Butter having been all the time exposed to the Air, smelled ill. Decemb. 7. The Cold coming on again, the Mercury returned to the Top of the Gage. The Butter in the open Air smelled worse. Decemb. 24. The Butter had yielded no Air, but was all of a grateful Taste, except the Superficies of it, which was contiguous to the Leather. So That Butter may be Preserved a long time, if Preserved from the Contact of Air. EXPERIMENT XIV. Nou. 30. 78. Whiting and Oysters▪ ONE Receiver was filled with Whiting and Wine, another with Whiting and Oysters. When the Screws were Set, the Mercury in the Gage was compressed, but in 3 hours returned to its former Mark. Decemb. 2. The Cold increasing, the Mercury Sunk in both. Decemb. 4. The Cold ceased, and the Mercury ascended in that Receiver which contained the Oysters. Decemb. 5. In that which held the Oysters, the Mercury was Raised 20 Digits. Decemb. 7. It risen to 40 Digits. Dec. 9 No alteration in either; that in which the Wine was contained, remaining still below its first Height. Decemb. 20. The Contents of both stunk. But what was remarkable in this Experiment, was, that there was Corruption without a Generation of Air, in that Receiver which contained the Wine. EXPERIMENT XV. Decemb. 3.78. Raw Beef with Pepper and Cloves. RAw Beef with Pepper and Cloves being put into two Large Receivers, and as much Beer added as filled the Remaining space, in a little time after the Pressure of the Air growing more Remiss, the Mercury came almost to the open ends of the Gage. Decemb. 8. The Mercury ascended not. The Beef being taken out of one to be Boiled, had acquired a sweet smell from the Cloves, and the Liquor smelled like Hippocras. Jan. 2. 79. The other Receiver was opened, no Air being produced. The Flesh was uncorrupted; and being Boiled in Vacuo with an intense Fire, I observed, Air or Spirits broke out at the Stop-cock fastened to the Top of the Receiver. When the Receiver was Cool the next day, it was almost void of Air; The Flesh was Tender, and well Tasted, only it was Boiled a Little too much, having been on the Fire Six Hours. Hence it appears, that Beer impregnated with Aromaticks will preserve Flesh. EXPERIMENT XVI. Decemb. 4.78. Larks with Beef. TWo Larks with some Beef being shut up in a Receiver, with as much Ale as filled up the Space not possessed by them: Another was filled with Beef alone, and a Mixture of Beer and Ale. Decemb. 9 Some Pieces of the Larks which were exposed to the Air, began to smell ill; but those in the Receiver had not yielded Air enough to sustain 5 Digits of Mercury. In the other Receiver no Air was Generated. Decemb. 19 The Cover of the Receiver, which held the Larks being broke, Liquor ran out: The Beef and Larks were uncorrupt, and being Boiled Tasted gratefully, the Taste of the Beef being made pleasant by the Mixture of the Larks and Beer. Decemb. 23. The other Receiver being opened, the Boiled Flesh seemed pleasant. Hence it appears, that Birds may be preserved long in Beer and Ale. EXPERIMENT XVII. Decemb. 14. ONe Receiver was filled with a whole Apple, Apples and Sugar, etc. and a sufficient quantity of Powdered Sugar. A Second was filled with an Apple cut in Pieces, and Sugar. A Third was filled with an Apple cut in Pieces and Water, with a 1/10 part of Sugar. A Fourth had 5 parts of Water, and one of Sugar included with an Apple cut in Pieces. Decemb. 21. In the first the Sugar was not Melted; The Mercury ascended a little. In the Second the Sugar was Melted and the Apples shrivelled; they yielded much Air when First included in the Receiver. In the other Two the Mercury ascended a little. In the Third the pieces of Apple were corrupted very much, for the Skin was taken off. Decemb. 22. Air was produced in all the Receivers, but most in the Second and Third. Decemb. 27. In the 3 First the Mercury was 10 Digits high, in the Fourth 6. Decemb. 31. In the 1st. and 2d. It was 13. In the 3d. 15. In the 4th. 9 Jan, 2. 79. In the 1st. and 2d. almost 14. In the 3d. 17. In the 4th. 11. Jan. 7. In the 2d. It was 16. In the 3d. 36. In the Fourth 15. The Mercury in the First risen no higher; but the Air made its escape, when the Screw was eased. Jan. 9 In the first it was 6 Inches high. In the 2d. 16. In the 3d. 39 In the Fourth 15. Jan. 17. In the 1st. 13. In the 2d. 19 In the 3d. 56. In the 4th. 17. Jan. 30. In the 3d. 76. Digits. The Liquor broke out, and therefore I opened the Receiver. The Fruit had communicated its Taste, which was pleasant, to the Water; The Mercury in the 2d. being raised no higher, I opened it, and found that the first was better Tasted than the former, and having communicated, in a great Measure, it's Taste to the ambient Sugar, It was in the form of a good Syrup. Feb. 16. The Mercury in the First Receiver was 22. In the Fourth 33. The Receiver being opened, I found that the Taste of the First being wholly imparted to the Water, had made it very Pleasant. Feb. 27. The Mercury in the First Receiver was 30 Digits high. March 15. The Receiver being opened, I found, that tho' the Colour of the Apple was good; yet the Pulp was Spongy, and had in a great Measure lost its Taste. Hence it appears, that Sugar does not preserve Fruit so well as Fermented Liquors. See EXP. VII. EXPERIMENT XVIII. Decemb. 23. A Glass Vessel being full of Milk, Milk included in a Receiver. and stopped with a Screw, was conveyed into one Receiver, and Milk with a Lark in it into another. Decemb. 24. In the Evening the Caseous and Butyrous Parts were separated both in the Milk in the Receivers, and in some of the same exposed to the Air. Decemb. 27. No Air generated where the Lark was; The other Gage was spoiled. Decemb. 31. The Mercury was raised in that which held the Lark. 3 days since, Milk that had all the while been exposed to the Air, Stunk. Jan. 1. 79. The Mercury was 10 Inches high, where the Lark was contained. Jan. 2. It was 14 ½. The Milk below the Butyrous Part seemed red. Jan. 4. It risen to 19 Digits. White Serum grew together in the Bottom of the Milk. Jan. 9 The Mercury was 29 Digits high. Jan. 25. The Receivers being opened, the Lark Smelled strong, but when Bolled Tasted Pleasant; tho' it had been kept 32 Days. In the other Receiver the Butyrous part was sour, but the Caseous Part Tasted subacid. From hence it appears that Milk may Preserve Flesh. EXPERIMENT XIX. Decemb. 24. 78. A Lark was put into a Small Receiver, A Lark with Melted Butter. and the Remaining space filled up with Melted Butter. Decemb. 27. The Mercury sunk, the Butter grew Yellow below, White in the Middle, and Fluid above. Jan. 5. 79. The Mercury gradually risen. 9 It was a little higher. 28. It was altered but little, the Receiver being opened; the Butter contiguous to the Leather which Lined the Cover, was of an ungrateful Taste and white. The Rest of the Butter was Yellow and Rancid. The Lark being Roasted was Pleasant to the Palate. Hence it appears, that Butter when Melted and hot, does not preserve Flesh so well as otherwise. EXPERIMENT XX. Jan. 4. 79. A Receiver being filled with Boiled Flesh and Broth, whilst the Screw was Set, Boiled Flesh and Broth. they were so Compressed as to Raise the Mercury 6 Digits, but it soon subsided again. Jan. 28. The Mercury had subsided 8 Digits below its usual Height. The Receiver being opened, we found the Flesh Sweet and Pleasant; The Broth Subacid and well Tasted. This Experiment Teaches, that Beef being kept in Receivers as long as Experience shows that it may, and then taken out and Boiled, and included again in Receivers, may be carried to Sea without Salting it, which may be of no small use in helping to preserve Beef Fresh in long Voyages. See. EXP. XII. EXPERIMENT XXI. Jan. 30. 79. Raw Flesh with Pepper and Cloves. RAw Flesh was included with Pepper and Cloves in one Receiver, and in another by itself. Feb. 11. In the First the Mercury was 3 Digits high. In the Second almost 1 ½. Feb. 12. In the First 4 ½. In the Second 1 ½. Feb. 13. In the First 6 ✚. In the Second 3. The Flesh of the First being boiled was Tender and Pleasant. Feb. 14. In the Second 5 19 In the Second 6 20 In the Second 11. The Flesh being Boiled was Tender and good, tho' it was kept in B. Mariae but 5 hours. Some of it before it was boiled was put into a Receiver free from Air. Feb. 28. The Ascent of the Mercury was small. March. 20. The Mercury was 16 Digits high. The Flesh being taken out Tasted Pleasant, but was inclining to corruption. EXPERIMENT XXII. Feb. 10. RAw Beef Seasoned with Pepper and Cloves was put into one Receiver. In another it was enclosed with Salt. In a Third alone. Feb. 19 In the 1st. and 3d. the Mercury ascended. In the 2d. it did not. Feb. 21. In the 1st. it was 4 ½: In the 3d. 10: In the 2d. 0. 25 In the 1st. it was 6: In the 3d. 19: In the 2d ½: 26. No Ascent: The Third being opened, and the Flesh Boiled, it tasted well. In the former Experiment Spices seemed to hinder, but here they promote the Generation of the Air: So that I am inclined to think, that the difference in these two Experiments depends on this, Viz. that in the former the Ingredients were shut up so close that there was no Room for Air to be Generated in. March 9 The Mercury in the 1st. was 8 Digits; In the 2d. None. 12. In the 1st. it was 12; In the 2d. 1. April 3. In the 1st it was 11: In the 2d 1. April 3. In the 1st it was 11: In the 2d 1. The Receiver being opened and the Flesh boiled, it was sweet and tender. From this Experiment we may infer, that Salt hinders the Generation of Air. Less air was generated in the second Receiver, because it was more exactly filled. To preserve Flesh without Salt the Air must be kept out; and likewise there must be a great compression in the Receiver. Of what use these Experiments may be for to help Mariners to transport fresh Meat and Fruits, the Reader may judge. ARTICLE XVIII. Experiments concerning Elixation and Distillation in Vacuo. EXPERIMENT I. Dec. 12. 78. Beef boiled in Vacuo. A Reciver large enough to contain 22 Ounces of Water, having 2 Ounces and 6 Drachms of Beef in it, was immersed 3 hours in boiling Water, and then lest to cool all Night; I found by the help of our Pneumatick Engine that the Air formed in the Receiver, was not able to hold up 3 Digits of Mercury: So that by deducting from the Calculation, one may learn that Flesh, whilst boiling, cannot generate a sufficient Quantity of Air to cause an entire pressure in a Receiver large enough to hold a double Weight of Water: That is, a Pound of Flesh shut up in a Receiver capable of containing 2 Ounces of Water, will not yield Air enough to sever the Receiver from the Cover without the help of heat. EXPERIMENT II. Dec. 23. THree Ounces of Beef being shut up in a Receiver large enough to contain 32 Ounces of Water, when it had boiled long, separated the Receiver from the Cover, so that Vapours got out. The Receiver being close again, it was a good while before the Cover and it were severed a second time: If the Fire be strong enough, sweet Exhalations continually make their way out. Dec. 24. The Receiver being cool, was almost wholly evacuated by the Pneumatick Engine: So that it appears, that the Receiver and its Cover are not separated by Air which is able to continue in that Form; but by violent exhalations, which when resisted, fall back, and condense in the Receiver, so that if the Fire be not too violent, the Avolition of those Steams may easily be prevented. EXPERIMENT III. Jan. 21. 79. Paste without Leaven in Vacuo. Passed without Leaven being shut up in Vacuo and in another Receiver with Common Air: And both of these shut up with a Screw in Balneo Mariae, I left them there 3 hours, and then after they had been exposed to a moderate Fire, I caused them to be opened. The Paste in Vacuo was reddish on its Superficies, the other was not boiled enough, therefore both were shut up in B. M. all Night. Jan. 22. The Paste being taken out, was sufficiently boiled, but had no Crust. That in Vacuo, was full of Cavities and insipid; the other was well Tasted and of a Close Body. Both Receivers were void of Air. EXPERIMENT IU. Feb. 3. 79. When Leavened Paste had filled a Receiver full of Air, it was removed into another, upon which it stunk; yet when it was in a hot Balneo M. 3 hours, Bread was made of it full of holes, but without a Crust. Feb. 5. The same Experiment being repeated without removing the Paste from one Receiver to another and exposing it to the Air, the Bread made of it was much lighter than the Former. EXPERIMENT V. Feb. 12. Rosemary and Water distilled in Vacuo. ROsemary and Water being shut up in the Instrument, contrived to distil in Vacuo, that being placed in Balneo Mariae, it yielded a Water which had a sweet Smell; as also some Drops of essential Oil, well scented and clear from any Empyreuma. But the Stop-cock being opened to let in Air, the Noise which the Air rushing in caused, was soon over, so that I judge the Rosemary had afforded a good deal of Air. Feb. 13. The same Rosemary being again exposed to a more violent Fire, it only yielded a Water less odoriferous than the former. EXPERIMENT VI. Feb. 10. 79. Flesh boiled in Vacuo. A Pound of Flesh was boiled in Vacuo, with 4 pound of Water, and in 3 hours the Mercury, in a Gage which was contained in the upper Part of it, was not raised above 3 Inches. It Tasted ill, as also the Liquor which was made of the condensed Vapours; it was not boiled enough. Feb. 11. The same Experiment was repeated, the Flesh being first sprinkled with Pepper and Cloves, the Mercury ascended 6 Inches, in the same time that before it was raised 3: It Tasted well, and the Liquor formed of the Vapours Tasted strong of Pepper. These Vessels seem proper to distil Bodies that are very thin and Volatile in. ARTICLE XIX. Concerning Elixation in Vessels stopped with Screws, by whose help, Hartshorn and the Bones of Fishes and fourfooted Creatures may be softened. EXPERIMENT I. Jan. 29. Beef boiled in B. M. BEef boiled in Balneo Mariae eight or nine hours, in a Vessel stopped with a Screw, had a very unpleasant Taste: After I boiled Beef seasoned with Pepper and Cloves 3 hours and it Tasted very pleasant: Beef that was not so Seasoned being boiled 3 hours Tasted well. So that I conjectured that the first Flesh was spoiled with over-boiling, when the Flesh was not seasoned, Vapours gathered in the Top of the Vessel, and condensed Tasted unpleasant. EXPERIMENT II. Jan. 29. APples boiled 2 hours, were soft and well Tasted; but some Pieces, impregnated with the condensed Vapours, which were of an ungrateful Smell, had acquired a less acceptable Taste. EXPERIMENT III. Feb. 4. Season Flesh enclosed in a Receiver. FLesh closely compressed and seasoned with Pepper and Cloves, being shut up in a Receiver stopped with a Screw, that was kept hot in Balneo an hour, in which time the Flesh was alittle over boiled: when the Balneum was opened, all the Water broke out. Feb. 5. Some Part of the Water was enclosed in a Receiver shut up with a Screw. March 12. The Flesh was very good. Elixation, by how much the more perfect, contributes the more to the hindrance of Fermentation. See Art. XVIII. Exp. XII, XX. EXPERIMENT IU. Feb. 10. Cow-heel boiled in Vacuo. A Cow-heel being boiled, four hours over a moderate Fire, was so soft, that the Bones might be eat like Cheese. Feb. 12. A Cow-heel being boiled 12 hours, Tasted Empyreumatical, and the Juice would not Coagulate: So that hard Bones and Tendons in Balneo Mariae may become good Nourishment. EXPERIMENT V. Feb. 10. A Fish boiled in B. M. 2 hours Tasted well, and the Bones were very soft. The Juice hardened presently into a Jelly of a firm Consistence. This is a good way to boil Fish that are full of Bones. EXPERIMENT VI. Feb. 5. Hearts-horn boiled in Vacuo. Hartshorn boiled 4 hours, was very soft like Cheese, and the Juice presently hardened into a Jelly. Feb. 17. The Experiment being repeated, the Hartshorn was Boiled 6 hours, and grew very soft: The Juice getting out of it, hardened into a Jelly, and stuck to the outside of it. These Experiments may be of great Use to Mariners, since by them they may learn how to boil their Meat with out consuming fresh Water, which may be kept for other more cogent Occasions. CHAP. IU. New Experiments about the Preservation of Bodies in Vacuo Boyliano. EXPERIMENT I. Several Substances included in Vacuo. A Piece of roasted Rabbit was preserved in Vacuo above two months' unalter'd. EXPERIMENT II. WHite Bread being enclosed in Vacuo from the 11th of March to the 1st of April, was unalter'd, save that the outside of some Crumbs were a little dry; nor was it any further altered in 17 days time more. The inside of the Receiver was not Moist. EXPERIMENT III. MIlk having been shut up in Vacuo three Months, smelled and Tasted sowrish, being turned partly into a Whey, and in Part into a soft Curd. EXPERIMENT IU. VIolet Leaves being shut up a Month and 2 days in Vacuo, had undergone no Alteration, but that they had lost their smell by being crushed down into the Vessel; it being usual for them by crushing to exchange their Fragrancy for an earthy Smell. EXPERIMENT V. SOme Violets being kept 7 Months in Vacuo, some retained their proper Colour, others looked like white Violets. EXPERIMENT VI. Sheep's Blood being shut up in Vacuo, whilst the Receiver was exhausting emitted Bubbles and swelled: Being kept in a heat equal to the heat of a digesting Furnace, for two days, was Florid and Fluid; afterward it inclined to a Blackness: Eighteen days after, external Air rushing in, and the Glass which held the Blood, being in a light Place; we perceived the lower side of it to be covered with a Coagulated substance of a deeper Colour than that which swum upon it; but when, by shaking, it was raised, it seemed of a fair Colour: The Blood being poured out, had no more an offensive Smell than the Blood of a newly killed Dog. EXPERIMENT VII. CReam being shut up in Vacuo near a Year, was like Butter on the top, which by agitation was separated from the Buttermilk it swum in: The Buttermilk was of a grateful Sourness, like other Buttermilk; but the Butter was Sourer. EXPERIMENT VIII. SOme slices of roasted Beef being put into one Vial; White Bread into another; and pieces of Cheese into a third, on the 15 of September; February the 18 we perceived little Alteration; they being free from Putrefaction. EXPERIMENT IX. Jvlyflowers and a Rose being enclosed in a Vial on the 12th of August; February 18 they were a little moist; but retained their Shape and Colour. In these two Experiments no Dew was perceived in the upper Parts of the Receiver. EXPERIMENT X. STrawberries being included in Vacuo, June the 4th: In the beginning of November we found them altered in Colour, but not in Shape. No sign of Corruption appeared. EXPERIMENT XI. ROasted Beef, Cheese and a French Rose being included in three distinct Receivers in Vacuo, May the 2d; were unalter'd September the 5th: Flowers were preserved unalter'd 8 Months and a half. EXPERIMENT XII. A Pint of Beer, which was a Year Old, being shut up in Vacuo, June 17; tho' in August Thunder turned the Drink in our Cellar Sower; yet that in Vacuo appeared unalter'd September 1. EXPERIMENT XIII. ALe being enclosed six Weeks in Vacuo; tho' Thunder happened which turned the Ale in the Cellar Sower, yet this was good as before. EXPERIMENT XIV. BLackberries included in Vacuo September 1st, 70; June 20th 73 were free from an ill Scent, and not in the least Mouldy; some sour Liquor being taken out from under them, they were shut up again. Octob. 11. 74. They were much blacker than before: No other perceivable Alteration. It is not a little strange, that so tender a Fruit should thus be preserved so long. POSSCRIPT. TO show that Liquors, by being Hermetically sealed in Bolt-heads, may be kept from sowering a long time, June 14 we shut up good Ale in one; the 5th of July next Year after, it was not sour: In 13 months' time after it was turned a little Sower. This Ale was preserved much longer from sowering than otherwise it would. June 14. 70. A Pint of French Claret being shut up, July 5, 71 was clear and high Coloured, and had deposited a Sediment. When the Glass was broken, white Streams risen plentifully from the Wine, which presently disappeared again: The Wine was rough, but well Tasted. July 6. It was shut up again. August 5, next Year the Wine Tasted well. June 20, 73, it was still good, and therefore Sealed up again. Octob. 11. 74. It was opened again; and appeared to be well Coloured, but less Spirituous; yet it was not Sour. CHAP. V New Pneumatical Experiments about Respiration, upon Ducks, Vipers, Frogs, etc. communicated in the Philosophical Transactions of August the 8th and September the 12th 1670. contained under the following Titles. TITLE I. Observations made about the lasting of Ducks included in the exhausted Receiver. EXPERIMENT I. Animals shut up in Vacuo. TO try whether Ducks, which continue a good while under Water without Respiration, would bear the absence of Air much longer, than other Animals in Vacuo, we enclosed a Duck in a Receiver, which was third Part filled by her: The Air being exhausted she continued well longer than a Hen would have done; yet in a Minute she was discomposed; and in two, she, after violent Convulsions, hung down her Head as if dead, but presently revived when Air was let in. Being shut up much longer in Common Air, she was not Discomposed. EXPERIMENT II. A Duck. A Callow Duckling being shut up in a Receiver, in a Minute seemed disordered: In less than two Minutes being ready to die and violently Convulsive, we let in Air; upon which she recovered. Being shut up 6 Minutes with Common Air, she seemed well. N. B. The Duckling seemed much bigger when the Air was exhausted, than before. TITLE II. Of the Phenomena afforded by Vipers, included in an exhausted Receiver. EXPERIMENT I. A Viper. TO try what effects Air would have upon Vipers, (Animals constituted differently from other Creatures) January 2, 6 ⅖ A Viper was shut up in a Receiver; as the Air was drawn out she began to swell, and soon after we ceased Pumping, she began to Gape. In 2 ½ hours she did not appear to be quite Dead: Soon after she gaped, the swelling subsided, but presently risen again. EXPERIMENT II. ANother Viper being shut up in Vacuo, after she had moved a little up and down, began to froth at the Mouth; soon after we left pumping, her Body and Neck swelled prodigiously, and a Blister rose on her Back, 1 ½ hour she appeared to be alive, but no longer. Her Neck and a great part of her Throat seemed transparent; Her Mouth was open and distorted; The Epiglottis with the Rimula Laryngis was almost thrust to the end of the Nether Chap. The black Tongue arising from beneath the Epiglottis, reached beyond it, but seemed dead. The Mouth was black within. Upon a Readmission of Air, in 23 hours, the Mouth was shut, tho' it opened again. Scorching or pinching the Tail caused Motion in the Body of it. EXPERIMENT III. A Snake. A Snake, being enclosed 22 hours with a Gage in a Receiver, seemed dead; but when held something near the Fire, put out her forked Tongue. The next day she was dead, her Jaws gaping as if stretched with Violence. TITLE III. Phaenomena afforded by Frogs in an exhaust-Receiver. EXPERIMENT I. Sept. 9 1662. A Large Frog being shut up in Vacuo, Frogs in Vacuo. was but little swelled, and moved her Throat almost as fast as before the Receiver was evacuated. Her Body swelled more, and she continued alive about 2 hours. In a little more than 3 hours she seemed dead; but being left all night upon the Grass; she recovered again. EXPERIMENT II. A Frog being enclosed in a Receiver almost totally exhausted, about 11 a Clock; at the first seemed unalter'd, but in six hours died. EXPERIMENT III. Sept. 6. 62. A Slender and a large Frog being both included in a Receiver; whilst it was exhausting, the Lesser skipped up and down, and some time after; but in a quarter of an hour seemed dead. The Larger Frog swelled a little, and continued alive half an hour; but the Receiver leaking, we pursued the Experiment no further. EXPERIMENT IU. A Small Frog being included in a Receiver, at the first seemed lively; but after, moved up and down as if very uneasy; yet was alive when the Receiver was wholly exhausted for the Space of an hour, but at the latter end of the time, she wanted Respiration, and her Belly and Throat were swelled. In 3 ½ hours time, the Air being let in, the Abdomen and Throat subsided, and instead of a Swelling, there remained a Cavity. EXPERIMENT V. A Large Frog being shut up in a plated Receiver exhausted, in seven hours was dead, being much swelled; but upon an Ingress of Air, was lanker than ever. TITLE iv Of the Phaenomena afforded by a newly kittened Kitling in Vacuo. A Kitling in Vacuo. A Newly kittened Kitling being included in a Receiver, when it began to be exhausted, in a Minute, after Convulsions, lay with the Tongue out as if dead; but when exposed to the Air, in a Trice recovered. Another Kitling of the same Age, being included in the same Receiver, after it had been, by turns, convulsive six Minutes, upon pumping out the Air, seemed dead; and when taken out of the Receiver, lay with its Tongue out, without either Pulse or Respiration; but being pinched, it presently gave signs of Life, and in a quarter of an hour, gaping and straining to fetch Breath, it recovered. A third being put into the same Receiver, after violent Convulsions and want of Breath, in a Minute and half seemed dead, no more Air being drawn out, than what was done at 3 Exsuctions. The Pump being still plied, and the Kitling seeming to swell, some time after gave signs of Life, being violently convulsed. After it had been enclosed 7 Minutes, we let in the Air, and put Aq. Vitae into the Mouth of the Kitling, yet it died in our Hands. These Animals continued perhaps 3 times as long alive in Vacuo, as others would have done. TITLE V Some Trials about the Air, usually harboured in the Pores of Water, etc. Air concealed in the Pores of Water. TO try how much Air is contained in a Quantity of Water, in reference to their Bulk: We filled a Chemical Pipe 36 Inches long, with Water, and inverted it in a Glass Vessel about ¼ of an Inch deep, and 2 Inches Diameter. These being included in a Receiver, the Air was pumped out, and upon a Readmission of it, the Bubble collected at the Top, wanted 8/10 of about 100 part of an Inch. Soon after, a Tube, to be described by and by, was filled with the same Water, and inverted; and when the Receiver, into which it was conveyed, was so far exhausted, that the Water in the Pipe sunk even with the stagnant Water, Air was let in, and rose the Water within a Tenth part and ½ of an Inch to the Top. The Tube was 43 ¼ Inches above the stagnant Water; this Experiment being twice tried, the first time the Space possessed by the Air was ¼ of an Inch, and more; the second it was ½ and 1/15. The first time the Water subsided level with the stagnant Water: In the second Trial, within 4 or 5 Inches of it. In these Experiments it was observable, that tho' the Air possessed so little Room in the Pores of the Water, that the Water seemed not to subside when it was drawn out; yet, the Air in the Cavity of the Tube, possessed a considerable Space. Quare. Whether Water freed once of its Air, will yield Air again? and whether there is not Air enough in the Pores of Water, to be serviceable to Fishes, when sucked through their Gills? To discover more nicely what Quantity of Air is contained in the Pores of Water, we made use of a Pipe, which consisted of a Globous Part 3 ½ Inches Diameter, and a Stem 9 Inches long; an Inch of which, at the Top, was melted and drawn out 2 or 3 Inches, till it was as slender as a Crow Quill: This Glass being filled with Water, was with a Pedestal conveyed into a Receiver, and upon evacuating of it, Bubbles plentifully risen, and made a kind of a Froth or Foam, but breaking at the Top of the slender Pipe, they did not run over. When the Receiver had been pretty well exhausted, we left off pumping till the Water had been pretty well freed from Bubbles; and so we successively pumped and left off again, till the Water seemed quite free from Air; and then, letting in External Air, the Water did not seem a Hairs breadth lower than before. The like Experiment was tried with Claret, which made us think it worth while to try what kind of Substances may be obtained from Aerial and Spirituous Bodies, by handling them thus. TITLE VI Of some Phaenomena, afforded by Shell-fish in an exhausted Receiver. EXPERIMENT I. Oysters in Vacuo. TWO Oysters in their Shells, being shut up in Vacuo; whilst the Receiver was exhausting, several Bubbles got out of the Shell; the Oysters were alive at the End of 24 hours. EXPERIMENT II. A Craw-Fish in Vacuo. A Craw-Fish being included in a Receiver, when the Air was pretty well exhausted, seemed dead, but revived upon a Readmission of the Air; when the Air was again exhausted, it was void of Motion; the Experiment being 3 or 4 times exhausted, and Air let in again, when the Fish was taken out, it seemed not to have suffered much harm. EXPERIMENT III. ANother Oyster being shut up in a Receiver, and immersed in Water, that the Bubbles which might come out of the Shell might be visible, if any; we found that this Fish was so strong, that no Bubbles could get out of the Shell. EXPERIMENT IU. A Craw-Fish stronger than the former, except one small Intermission, continued in Motion whilst the Air was exhausting. TITLE VII. Of the Phaenomena of a Scale Fish, in an exhausted Receiver. A Gudgeon in Vacuo. WE filled the Globous Part of a Receiver, which was shaped like a Bolt-head, and large enough to hold a Pint, half full of Water, and put a Gudgeon 3 Inches long into it, which swum up and down; this being done, we exhausted the Receiver so far, that but one part of twenty of the Air was drawn out, and then we observed the following Particulars. First, The Water, except about the Fish, afforded no Froth, and but few Bubbles. Secondly, The Fish discharged several Bubbles at its Mouth and Gills, and several, after it rested half an hour, stuck to its Fins and Tail, and other Parts; these Bubbles by swimming would be shaken off, but upon a little Rest, they would appear about him again. Thirdly, Except at the latter End, he seemed to take in Air at his Mouth and Gills. Fourthly, After a while, he lay on his Back, and would swim in that Posture. Fifthly, In some time he moved more lively than at first. An hour and half after he was included, he seemed clear of Bubbles, but lay on his Back, and was a little tumid, yet as lively as before. An hour and a ¼ after he was without Motion, and stiff, yet being excited by Motion, he moved a little. Air being let into the Receiver, whilst he was under Water, he sunk to the Bottom, and seemed a little revived, and being conveyed along with the Water into a Basin of fresh Water, he was further recovered; yet could not lie on his Belly, but turned from one side to the other: his Belly seemed much shrunk; he was alive at 24 hours' end, and then was able to lie on his Belly. TITLE VIII. Of two Animals included, with large Wounds in the Abdomen, in the Pneumatical Receiver. EXPERIMENT I. ABird in Vacuo. A Small Bird, whose Abdomen was opened tranversly, in about a Minute after we began to Pump, had Convulsions in its Wings; and being taken out, was past Recovering, tho' there was very little Alteration in its Lungs, and the Auricles of its Heart continued to beat. EXPERIMENT II. A Frog in Vacuo. A Frog, whose Abdomen was so much opened, that two curled Lobes of its Lungs came out at the Incisions, was suspended by the Leg in a small Receiver, which when it was in some Measure exhausted, lay void of Motion, its Abdomen and. Thigh being swelled very much, as if distended with some Airy Vapour. One Lobe, when the Frog was shut up, appeared full, the other shrunk up, and thus they continued, till Air was let into the Receiver again, and then the Body growing less tumid, and the Lobe of the Lungs which was tumid, subsiding, it presently recovered. TITLE IX. Of the Motion of the separated Heart of a cold Animal in the exhausted Receiver. EXPERIMENT I. The Heart of an Eel in Vacuo. THE Heart of an Eel being shut up in a Receiver upon a Tin Plate, beat as in the open Air; and the Receiver being exhausted, grew tumid, emitting several Bubbles out of it; yet it continued to beat as fast, or faster than in the open Air. The like Success we had with another. EXPERIMENT II. THE Heart of another, tho' tumid, beat an hour in Vacuo, and then beginning to fail, I applied Heat to the Glass, upon which, it renewed and continued its Motions another hour; at which time, it's Motion was renewed, by applying of Heat a second time; at the end of the third hour, the Motion, which was but a trembling one, could neither be promoted by the Air, nor Heat. TITLE X. A Comparison of Times, wherein Animals may be killed by drowning, or withdrawing of the Air. EXPERIMENT I. Sept. 10. Animals in an exhausted Receiver A Green-Finch being sunk in Water by a Weight, was dead after it had lain half 0184 0108 V 3 a Minute without Motion. EXPERIMENT II. A Sparrow, which at the first moved very vigorously under Water, being taken up, after it had lain half a Minute without Motion, was past Recovery. EXPERIMENT III. A Mouse being immersed half a Minute, and some Seconds, after some faint signs of Life, though not Convulsive, died. EXPERIMENT IU. A Duck, being immersed by a Weight, after it had lain quiet for a Minute, was a little uneasy; but being quiet at the end of the second Minute, we took it out, and in a little time it recovered; but being immersed again in fresh Water, it emitted several Bubbles at its Beak and Nostrils; and in two Minute's time, began to struggle: At the end of four Minutes ceasing to emit Bubbles, it began to gape, which continued two Minutes, and then its Head hanging carelessly down, it seemed dead; being taken out a Minute after, it was past Recovery. EXPERIMENT V. A Duckling being immersed with its Beak about 2 Inches under Water, emitted Bubbles at its Beak, which likewise arose from some place in its Neck, about as far from its Eyes as from its Ears, after which, several times it endeavoured to dive lower, and having been moderately convulsed, hung its Head down, as if dead at 3 Minute's end; soon after, a trembling Motion appeared in some parts of its Bill, but that ceasing, at the end of the 4th Minute, it was taken out past Recovery. EXPERIMENT VI. A Viper was so long kept in Vacuo, that it seemed dead; but, being kept all night over a digestive Furnace in a Glass Body, was as lively as ever. Then we immersed it in a Glass Body stopped with a Cork, and depressed with a Weight; where it lay a considerable time, with very little Motion; when four hours were almost past, it swum above the Bottom of the Water, and had several times put out its Tongue; when a little more than seven hours were passed, it seemed dead, its Head and Tail hanging down without Motion. N. B. Tho' several of these Animals seem to die a little sooner in Water, than in Vacuo; yet it does not certainly prove, that the former kills them faster, for in Water they are deprived of Air instantly; In a Receiver, by degrees; which is evident from hence, viz. That having provided a Receiver which could be exhausted at one suck, the Animal contained in it would be dead in half a Minute. TITLE XI. Of the Accidents that happened to Animals in Air brought to a Considerable Degree, but not near the utmost one of Rarefaction. EXPERIMENT I. Aug. 18. A Linote being 3 hours in a Receiver, Several Animals in Vacuo. large enough to hold 4 ½ Pints, seemed sick; but being taken out, recovered. EXPERIMENT II. Aug. 18. A Linote being enclosed in a Receiver half exhausted, was not in danger of Death in less than 1 ¼ hour, and then being exposed to the Air, Recovered. EXPERIMENT III. Sept. 9 A Lark being included in a Receiver of the former Magnitude, together with a Gage; when ¾ of the Air was exhausted, in a Minute and half was taken with Convulsions, and at the end of the second Minute, was past Recovery. EXPERIMENT IU. Sept. 9 A Green-Finch being shut up in the same Receiver, half exhausted, in a Minute was sick, and threw Matter, which she vomited, upon the side of the Glass; upon which, she seemed better, and continued so for 3 Minutes, and then being sick, and vomiting as before, she eat part of it up, and seemed again to recover; some Air getting in, though it was pumped out again, for the last Eight Minutes, she seemed better than we expected. At the end of a quarter of an hour, the Bird being not like to die, we took her out. EXPERIMENT V. A Viper, together with a Gage, being included in a Receiver, which held 3 1/● Pints of Water, for 36 hours after it was exhausted, moved up and down nimbly, and put out her Tongue often: At the end of 60 hours she seemed almost dead, and the next day at Noon was quite dead. The Receiver taking in as much Water as the included Air would admit, by measuring it, we found that 5 parts of six of the Air had been drawn out. A Digressive Experiment concerning Respiration on the Tops of High Mountains. Of Respiration on the Tops of Mountains. Upon Enquiry I was told, that the Mountains in Armenia are so high, that they cannot get to the Tops of them for Snow, and that those that go up high, are troubled with a shortness of Breath. And the like difficulty of Breathing hath been observed on a Mountain in the Country of Sevenes, in or near the Province of Languedoc. And one that had been on the Top of Picinino de Midi, one of the highest Pyrenean Mountains, observed the like shortness of Breath: And the Air on the Mount Teneriff, hath so violently affected some, that they were not able to climb to the Top of it. TITLE XII. Of the Observations produced in an Animal in Changes, as to Rarity and Density, made in the same Air. TO try whether an Animal that was almost dead, by being contained in rarified Air, would recover upon a Condensation of that, without admitting any fresh Air to come to it; we took a Lamb's Bladder, whose outside being oiled, to render it more transparent, we cut so much of its Neck off, that way might be made for a Mouse to be put in; which being done, that the Neck of the Bladder might be tied up so, that no Air could get in at the Wrinkles, we covered a Wooden Stopple with Cement, which squeezing into the Crannies, we could utterly exclude the Air. A Bladder thus prepared, being conveyed with a Mouse in it, into a Glass Receiver, we plied the Pump, till the Glass Vessel was so much exhausted, and the Air in the Bladder so far expanded, that the Mouse was like to die. Upon which, the rarified Air in the Bladder being again condensed, by admitting External Air into the Receiver, the Mouse was revived. The Experiment was a second time tried with the like Success. TITLE XIII. Of an unsuccessful Attempt to prevent the Necessity of Respiration, by the Production or Growth of Animals in our Receiver. EXPERIMENT I. Respiration necessary absolutely continue Life. A Good Company of Tadpoles being shut up in a Receiver, upon the first Exsuction, they risen to the Top of the Water; and though they subsided again, yet upon the second, they risen again, and seemed to be discomposed; when the Receiver was exhausted, they swum upon the Top, being not able to dive down; and in an hours time, they became destitute of Motion; when the Air was let in, they sunk to the Bottom, but recovered not. EXPERIMENT II. THE like Experiment being tried with a less number in a less Receiver, tho' they were supplied with Air sooner than the others, yet very few recovered. EXPERIMENT III. THE same Experiment with the first, being tried some Years after in another Receiver, we had the same Success. EXPERIMENT IU. WE included some of those Infects in a Receiver with Water, which first live in Water, and then turn winged Infects; which swimming up and down a few days, put off their exuviae, and were perfect Gnats, which stood upon the Water, and lived a considerable time. A digressive Experiment concerning the Expansion of Blood and other Animal Juices. The Blood and other Humours expanded. Lamb's Blood preserved from Coagulation was conveyed into a Receiver in a wide mouthed Glass: When the Receiver was pretty well exhausted, the more spirituous Parts of the Blood making their way out, raised the more clammy Parts into large Bubbles; and the Expansion of the volatile Parts were so vehement, that it boiled over a Glass, of which it filled but ¼ part. Having included warm Milk in a Cylinder 5 Inches high, the Quantity of it being only 3 Ounces, it boiled so impetuously when the Air was totally exhausted, that several parcels of it flew out of the Vessel. Gall discovered a greater degree of Intumescence. N. The design of these Experiments was to know, whether when the Air is drawn out of a Receiver, Animals may not be prejudiced by an Expansion of the Humours in the Capillary Vessels, as well as by an Absense of Air, since the Parts of them distending the Vessels may, stop Circulation, and cause Pains and Convulsions. I once observed a Bubble to move to and fro in the Humours of one of the Eyes of a Viper in our exhausted Receiver. Another Digressive Experiment. The Liver and Heart of an Eel, together with the Head and Body of another, being conveyed into a Receiver; when the Air was exhausted, the Liver manifestly swelled, and several Bubbles seemed to arise from the Medulla Spinalis, or the Parts adjoining. The Air being let in, the swollen Parts subsided, and the Skin seemed more flaccid than before. TITLE XIV. Of the Power of Custom to enable Animals to hold out in Air too much Rarified for Respiration. EXPERIMENT I. The Prevalency of Custom to enable Animals to continue in Vacuo. A Small Mouse being conveyed into a Viol with a Wide Neck, a Bladder was tied upon it, which had all the Air expressed out of it. This being conveyed into a Receiver with a Gage; a fourth part of the Air was only remaining in it; upon which, the Bladder was half distended with rarified Air, and the Mouse was very uneasy, and ill; but that rarified Air by an Ingress of External Air being condensed, it presently recovered. EXPERIMENT II. THE Experiment being repeated, and the Mouse kept in the rarified Air four Minutes, was very ill, and with much difficulty recovered in the outward Air, trembling for a long time. EXPERIMENT III. THE same Mouse being again shut up, was a quarter of an hour in rarified Air, and when taken out, sooner recovered than before, and with less trembling. EXPERIMENT IU. THE same Mouse being again conveyed into a Receiver, after it had recovered its Strength, the Air was a little further rarified than before: At the first, the Mouse seemed discomposed; but after continued quiet a quarter of an hour. The Air being expanded by three Exsuctions more, it seemed ready to die, but Air being let in again, it presently recovered. TITLE XV. Some Experiments showing, that Air, become unfit for Respiration, may retain its wont Pressure. EXPERIMENT I. Air unfit for Respiration retains its usual Pressure. A Mouse being shut up in an Oval Glass hermetically sealed, and a Gage suspended by a Wire in the Neck, in 2 ½ hours we found it dead; and with much ado recovered, when Air was blown in with a pair of Bellows, the sealed end of the Glass being broken off. The Station of the Mercury in the Receiver was not altered. EXPERIMENT II. THE same Experiment being tried with a small Bird, in half an hour it was sick and drooping, and in 2 ½ hours a difficulty of breathing gradually increasing, it died. The Gage was not sensibly altered. EXPERIMENT III. TO show that it is not a defect of Cold in an exhausted Receiver, that kills Animals included in it. We hermetically sealed a small Bird in a Receiver, large enough to hold 3 Quarts of Water; In a few Minutes it began to be sick and pant, and continued so half an hour: The Viol was immersed 6 Minutes in Water refrigerated with a Solution of Sal Armon. but the Bird was not refreshed; it vomited and purged, when taken out of the Water; and continuing to pant as before, in an hour from her first Imprisonment, died. TITLE VI Of the Use of the Air to elevate Steams of Bodies. The usefulness of Air to raise Steams from Bodies contiguous to it. TO prove that the Air carries off the fuliginous Steams from the Lungs in Respiration; We prepared a Red Liquor, consisting of such Saline and Spirituous Parts, as the Mass of Blood yields: This Liquor well stopped up in a Bottle, tho' it be but half full, emits no Steams; but when the External Air comes to it, it emits white Exhalations, which rise up into the Air. Whence it appears, that the Contact of the Air, may enable Bodies to emit Vapours. In this Liquor there are two things worth our Notice; the First is, that when the Viol hath lain quiet and stopped a competent time, the upper Part will appear void of Fumes, so that the Air will retain but a certain Quantity; which may help to give a Reason, why the same Air which will be clogged with Steams, in a short time becomes unfit for Respiration. The Second is, that in Vacuo for want of Air, tho' the Bottle was unstopped, these Exhalations would not rise; but as soon as it was let into the Receiver, they rising up plentifully, were drawn out along with the Air, a second time exhausted. This Experiment hath some Affinity with that Mentioned in the 29 of the Experiments of the Spring, and the weight of the Air in the first Volume, that being made with Corrosive Ingredients, and this of Medicines good for the Lungs. TITLE XVII. Of the long Continuance of a Slow-worm, and a Leech alive in the Vacuum made by our Engin. EXPERIMENT I. A Slow-worm and a Leech alive in Vacuo. WHite Snails without their Shells, being shut up in Vacuo had store of Bubbles sticking to them; but they put out and drew in their Horns at pleasure; in some Hours they became void of Motion and Tumid; And in the space of Twelve hours seemed like blown Bladders, the substance of their Bodies being consumed; The External Air being let in, they sunk together like two Skins, no signs of Life appearing, EXPERIMENT II. ANEft being included in an Exhausted Receiver 48 hours, it seemed swelled in its Belly; it's under Jaw moved the first Night, but not after. The Receiver being opened under Water and half filled, the Animal was very much revived. EXPERIMENT III. A Leech being included with a little Water in a Receiver, large enough to hold 12 Ounces; when the Air was Pumped out, the Leech keeping under Water, several Bubbles risen from distinct parts of its Body, yet it was not much indisposed. It continuing well five days, by opening the Receiver under Water, I found that it had been all the time well exhausted. TITLE XVIII. Of what happened to some Creeping Infects in our Vacum. EXPERIMENT I. SIX Caterpillars being shut up in Vacuo, two hours after, Creeping Infects in Vacuo. moved up and down: 8 hours after they seemed quite dead; but being exposed to the Air in the Morning were alive. EXPERIMENT II. Caterpillars being Shut up in two Receivers, to one we added the Air which was drawn out of the other Receiver. Those which had Air with them, were alive two days, the others in Vacuo seemed dead in a little time. TITLE XIX. Of the Phaenomena suggested by Winged Infects in our Vacum. EXPERIMENT I. Winged Infects in Vacuo. FLesh-Flies whose head were cut off, being included in a Portable Receiver; furnished with a large Pipe and a Bubble at the end of it; When the Air was drawn out, they lost their Motion; two hours after, Fire not being able to excite Motion in them, I let in the Air, and then they began to move; and were observed to move the next Morning. EXPERIMENT II. SEveral Ordinary Flies and a Bee or Wasp, lay as if dead in the exhausted Receiver, except some, which for a few Minutes were Convulsive; after 48 hours, they neither Recovered when exposed to the open Air, nor the Meridian Sun. EXPERIMENT III. A great Flesh Fly being put into a Portable Receiver was very brisk and lively till the Air was drawn off, but then was taken with Convulsions; the Air being let in again she Recovered, but it being a second time exhausted, she lay as dead till the Glass was stirred, and then she moved a little; the next Night after neither heat nor any thing else would recover her of a long time; but at the last, when she was well, being shut up again 48 hours and placed in a Warm place, she grew so ill as to be past Recovery. EXPERIMENT IU. A Grass-hopper whose Body was an Inch long, being shut up in an oval receiver large enough to hold a Pint; when the Pump was first Plied he was very uneasy, and several Liquid drops came from his Abdomen to the quantity of a quarter of a Spoonful; when the Receiver was pretty well exhausted he fell on his back and lay as dead. But the Receiver being placed in the Sunshine he moved a little, and soon after lay as dead 3 hours. But the Receiver being opened and placed, after he seemed dead half an hour, some time in the Sun beams, in a short time he recovered. EXPERIMENT V. A Rose-Flie being shut up in a receiver, struggled much whilst the Receiver was exhausting, but in 6 hours' time seemed dead; the Receiver being opened Four hours after, the Beetle was lively enough. The Receiver being a Second time exhausted, the Animal in the mean time seemed much disquieted. EXPERIMENT VI. SEveral Butterflies being Shut up in Vacuo, were not able to fly in so thin a Medium, but when the Receiver was inverted, would fall from one end to another rudely enough. TITLE XX. Of the Necessity of Air to the Motion of such small Creatures as Aunts and even Mites themselves. Air requisite to the Life of very Minute Animals. aunts being shut up in Vacuo, in Seven hours' time seemed dead; but the Receiver being opened, about 14 hours after they were most of them Recovered. Cheese, which had a great many Mites in it, was conveyed into Four several Receivers, Three of which were exhausted: The Mites in the unexhausted Receiver were alive a Week. In two of the exhausted Receivers they seemed dead, and continued so Four hours; but Air being permitted to rush in 3 days after, several of them were revived, and continued alive 2 or 3 days longer. In the other Receiver Mites which lay dead 3 days Recovered presently upon a Readmission of the Air. CHAP. VI The most Considerable Animadversions on Mr. Hobbs' Problemata de Vacuo. THe first Passage in Mr. Hobbs' Problemata de Vacuo taken Notice of is this, Viz. He says, Why contiguous Marbles are not easily separated. if a Vacum interspersum, were allowed in the Air, when two Flat Marbles are exactly adapted to each other's Superficies, they might as easily be separated, as moved, when separate in the open Air. To which it is Answered, that tho' there be several Vacuities interspersed betwixt the Particles of an Atmospherical Pillar of Air; yet notwithstanding, since each of those Particles are endued with a Specific gravity, and are incumbent on the surface of the uppermost Marble, whatever separates those two Bodies, must have a force able to sustain the weight of the Pillar of Air which leans on it. But when the Air is contiguous to each side of the Marble, having an equal Pressure on each side from the Ambient Atmosphere, there is required no more force to move it up and down, than is sufficient to surmount the Weight of it, etc. And tho' Mr. Hobbs says, that the Reason why two Marbles cannot be Separated suddenly, is, because the Air cannot instantly fill the space deserted by them; yet from Experiments already laid down; it appears, that they may be pulled asunder, and much more easily, in an exhausted Receiver where there is no Air to succeed the space left betwixt them upon their Auulsion. Where it is evident, that a force able to overcome the hardness of the Stone, is not requisite to draw them asunder, but only so much as is able to raise the Weight of the upper Marble; and in the open Air as much as is sufficient to overpower the incumbent Atmosphere. Another Argument against what Mr. Hobbs lays down in favour of a Plenitude, may be taken from the following Experiment. We took a Glass Bubble about as big as a Nutgmeg, and having Sealed up its Stem, we held it in a Flame, and as soon as it was ready to Melt, removed it into the open Air, where the Bubble, which was dilated in the Flame by the help of the included Air's spring, was pressed in on one side by the Weight of the Ambient Atmosphere, the Rarified Air, being condensed, and not able to resist the Pressure of the External Air; yet when the Bubble was again conveyed into the Flames, the Internal Air expanding plumped up the sides of the Glass, which were again compressed and bruised by the Weight of the open Atmosphere; and this Experiment being tried a Third time, Answered as when First repeated, till at last the one side of the Bubble had a hole made in it, by the violent Pressure of the Atmosphere; from whence it appears, that the same quantity of Air may, by being Rarified, and leaving Vacuities betwixt its Rarified Parts, be able to take up and possess a larger space; and that there must be Vacuities interspersed betwixt the Parts of that Air, is evident, since the Pores of the Glass are too sine, to admit External Air, or when the Bubble was compressed, to give way for an egress of the Air contained in it. A Second Argument Answered. Mr. Hobbs asserting, that the Cavity of a Receiver exhausted, is full of Air, the first Experiment here alleged against him, and which shows, that the Weight and pressure of the Atmosphere is very considerable is this: A Pewter Porringer being cemented down upon an Iron Plate, which was fixed to the Pump, we drew out the Air, upon which the Incumbent Atsmosphere depressed the Convex surface of the Porringer, and rendered it Concave; and in another Trial I took Notice, that the Atmosphere did not exert its Gravity in a perpendicular Line, but collaterally. The Reason of Bubbles in an exhausted Receiver. Mr. Hobbs ascribing the Reason of those Bubbles, which in an exhausted Receiver, appear for some time upon the Surface of Water, to the violent Motion of the Air contained in the Receiver, Mr. boil to disprove him, taketh Notice that when Water is once freed from its Air, let the Pump be Plied never so violently, the violent Motion of Mr. Hobbs' Air will not be able to cause Bubbles; so that the Phaenomenon rather depends on a want of Air to press on the Surface of the Water, and to overpower the Expansive force of that Air, contained in the Pores of it; which for want of such a Pressure makes its way through the Water it's contained in. Mr. Hobbs Explanation of the Torrecellian Experiment Examined. Mr. Hobbs' Explanation of the Torrecellian Experiment having been elsewhere Answered, to what hath been their delivered, I shall add the following Experiment; The Torrecillian Experiment being Tried with a strait Tube, we raised the Pipe a little in the stagnant Mercury; and then conveying a piece of a Bladder under the End of it, and tying it firmly; when the end of the Tube was raised above the stagnant Mercury, I observed, that the Weight of the Mercury upon the Bladder was very slight, and the Equilibrum betwixt the Mercurial and Atmospherical Cylinder was so equal, that if the Tube was but inclined, so that the Weight of the Mercury was not Perpendicular, the Atmosphere would buoy up the Bladder, and form a Concave in the lower end of the Mercury; but when the Tube was Erected again, the Bladder would be depressed, and become Protuberant: And if the Bladder was nimbly applied, when the Mercury was a little below its wont Station, the Mercury being then lighter than the Atmospherical Cylinder, the Bladder would be raised up into the Cavity of the Tube: In which Experiment we may Observe, that tho' upon the Ascent and Descent of the Mercury, the Cavity above it is accordingly varied in its Dimensions; yet no Air can Ascend to fill it, as Mr. Hobbs would suggest, since the Bottom of the Tube is shut up with a Bladder, which as I have elsewhere made it appear, cannot be penetrated by Air. Another Argument against Mr. Hobbs' Explanation of the Torrecellian Experiment, is deduced deduced from an Observation made on the Travelling Baroscope; for it is Observed, that when the shorter Leg is Sealed up with Air included in it, Heat will so Rarisie that Air, that it will elevate the Mercury in the longer Leg, without making its way through the Mercury below, as Mr. Hobbs supposes it does in the Torrecellian Experiment; where one would expect, that if Air condensed could Penetrate Mercury so easily, the rarified Air would rather penetrate than buoy it up. The Reason of Suction. To show, in Opposition to Mr. Hobbs, how much the Atmospherical Air is concerned in Suction, we took a Glass Bubble, whose long Stem, was Cylindrical and very slender, and having, by the help of heat, expelled a good quantity of the Air contained in it, when by immerging it in Water that Rarified Air which remained in it, was condensed; the Water was almost raised to the Top of the Pipe; when this was done, the Air in the Bubble being Rarified, it forced out almost all the Water in the Stem, only a few Drops, which satisfied us that none of the Rarified Air had got out of the Pipe; as the Depression of the Water so low assured us, on the other side, that the included Air was almost as much Expanded, as when the Water began to ascend into the Pipe. When the Air was thus Rarified, we presently removed the Pipe out of the Water into the Stagant Mercury, which ascended into it in a short time. In which Experiment, did the Mercury rise to prevent a Vacuum, or did its Ascent, depend on any internal Principle of Motion, or on the compression and propagated Pulsion of the Air that was expelled, there would be no reason, why the Mercury should not rise as high as the Water. But from our Hypothesis, the Reason is plain; for as soon as the Cylinder of Water or Mercury together with the compressed Air is equiponderant with the Atmosphere incumbent, it rises no higher; So that tho' the Air is less condensed, when the Tube is immersed in Mercury; yet the greater Weight of Mercury making a greater resistance than Water, the external Air is not able to buoy it up any higher to compress the Air enclosed. And this Experiment is confirmed by the following: For having expelled a little Air out of the Bubble by heat, so much Quicksilver ascended into it, as filled a Fourth Part of the Pipe; which being carefully removed, so that no Mercury could run out; we caused the Air in the globous part to be Rarified till almost all the Mercury was expelled, the end of the Pipe being all the while immersed in Water; as soon as the Air included begun to cool, the Water risen up into the Body of the Ball, buoying up the Mercury before it, whereit was observed, that as the Air was more or less Rarified, and the Quicksilver exeplled out of the Stem, the Ascent, of the Water would proportionably vary. So that as the Body to be buoyed up by the External Air varies in Weight, so do the Degrees of its Ascent. Another Observation, which shows that there is no Circulation of Wind, such as Mr. Hobbs supposes to be the Cause of Suction, is, that Smoak will ascend without being in the least blown about. But since Mr. Hobbs will not allow of a Vacuum, but asserts, that the Air makes its Way through the close and solid Bodies, I shall add, that having expelled the Air by Rarefaction, out of a very thin Aeopile, and stopped the Orifice up with Wax, the External Air made such a violent Pressure on it, as to thrust the Sides of it considerably inwards. CHAP. VII. The Cause of Attraction by Suction. Attraction, what. SUction being looked upon to be a sort of Attraction, before I descend to a more particular Consideration of the former, I shall premise something of the latter. And tho' Attraction is generally taken to be a kind of Pulsion, yet both of them to me seem to be but extrinsical Denominations of the same Local Motion; in which, if a Body moved, precede the Movent, or tends to acquire a greater Distance from it, we call it Pulsion; and if upon the Account of Motion, the same Body either follows, or tends towards the Movent, it is termed Attraction; so that the difference is no Physical one, but only Accidental, in respect of the Line of Motion to the Movent. As when a Man draws a Chain after him, tho' he goes before it, yet he hath some Part of his Body behind one Link, which draws the rest after it; and so if that Chain draws any thing after it, tho' the Cause of the Attraction goes before, yet there is a certain Cohesion of Parts, that enables it to drag that Body after it; so that Attraction evidently appears to be a Species of Pulsion, and such an one as is usually termed Trusion, as when a Gardener drives his Wheelbarrow before him without letting go his Hold. But perhaps it may be said, that there are Attractions where it cannot be pretended that the Attrahent comes behind any Part of the Body attracted; as in Magnetical and Electrical Attractions, or as when Water rises by pumping. As for the two first Instances, should we allow with Modern Philosophers, of screwed Particles and other Magnetical Emissions, we might say, that these coming behind either the Body attracted, or it's porous Parts on its Superficies might cause such an Effect; or by procuring some Discussion of the Air, that may make it thrust the movable towards the Attracting Body. But were there none of these, nor any other subtle Agents, that cause this Motion by a real, tho' unperceived Pulsion; I should, to distinguish these from other Attractions, term them Attraction by Invisibles. But as for the last Instance, I suppose it will be easily granted, that the ascending Rammer only makes way for the Water to rise, as it is buoyed up by External Air; for from the Torrecellian Experiment it is evident, that, since the Terraqueous Globe is continually pressed upon by the Atmosphere, if in any part, that Pressure be taken off, the Incumbent Atmospherical Pillar will buoy up as much of that Liquor, as a Pillar of Air of such a Diameter is able to counterpoise: The Truth of which is further confirmed by observing, that, if the Air from about a Syringe be exhausted, the Sucker may be pulled up without elevating the Water, or drawing it up after it. And indeed, supposing two Men, by thrusting equally on each side a Door, to keep it shut, one might as well say, that he that left off thrusting on one side, was the Cause of the Doors opening, as that the Water rises by the drawing up the Rammer, which only gives way to the Water as buoyed up by the External Air. Thus much being said of Attraction, I shall proceed to consider, The Cause of Suction, as laid down by others exanuned. that Species of it called Suction; for which several Philosophers have thought on various Causes. As Nature's Abhorrency of a Vacuum, which, were it true, Water by Suction might be raised to any Height; but we have found by Experience, that it will not be raised above 33 ½ Foot, which Weight the Atmosphere is able to buoy up; as appears from the Torrecellian Experiment. And further from an Experiment elsewhere laid down, where, tho' Water may presently be sucked up to the Top of a Pipe 3 Foot long, yet Mercury being too heavy to be buoyed up so high, it will not be elevated higher than an Atmospherical Cylinder is able to raise it. But those Modern Philosophers who allow not a Fuga Vacui, ascribe the Ascent of such Liquors to an Impulse or Propagation of Motion, by the Dilation of the Thorax; for they think, that the Lungs drawing in the Air, the dilated Thorax propagates the Impulse, till it reaches successively the Body sucked; for such thinking the Universe totally a Plenum, think that such Matter not finding any other Place to move into, does upon that score buoy up the Water or Mercury in the Pipe. But if we consider, how vast the Dimensions of the Air are, and comparatively how inconsiderable an Impulse the Thorax by dilating can make, it will scarce be thought, that so slight a one will compress the whole Air, so much as to make it impel the Body sucked vigorously enough to rise to that height, which Liquors may be raised to by Suction. But the Ascent of such Liquors evidently depends on this, that by Suction the Pressure is taken off the Surface of the Water, within the Pipe, and consequently, it must rise and be buoyed up by the Pressure of the Atmosphere, on the stagnant Water. To countenance my Opinion, and to refute the others I have mentioned, I shall offer the following Experiment, viz. A small Bubble with a Stem being sealed up, when the Air was forced out by Rarefaction, the Stem was broke under Water, upon which the Water rushed into the Cavity of the Bubble, where if it be said to go into the Bubble to prevent a Vacuum, those that say so, allow dari Vacuum, and subvert their own Principles; and as for the Plenists, upon the same Account we may ask them, what became of that Air which was expelled out of the Bubble, and remained so, till the Stem was broke; since were the World an absolute Plenum before, there could be no room for it without, nor could there be such an empty Space within to receive the Water. Besides, if they say the external Air being condensed and compressed by that which is forced out of the Bubble, occasions the Re-ingress of Water when the Stem is broke off, it may justly be wondered, that a cubic Inch of Air should be able to condense the Air so much, that a Mile's distance from the place the Bubble was evacuated in, it should be able to press the Water thus in again. But by our Hypothesis, it is accounted for without these Difficulties; since the Resistance of the rarified Air within the Bubble, being disproportionable to the Pressure of the less rarified Ambient Air, it must consequently yield to it, and give way to the Ingress of Water. Our own Opinion proposed and proved. From what hath been said, it plainly appears what our Hypothesis is, which that I may confirm by the following Experiments I shall briefly intimate: That the Ascent of Liquors by Suction, in a Word, depends on the External Pressure of the Air, when it is taken off the internal Superficies of the Liquor in that Tube; what that Pressure depends on we have elsewhere proved in our Physicomechanical Experiments of the Air's Spring and Weight, and therefore shall proceed to Experiments to confirm what we teach of Suction. We took then a crooked Syphon, whose shorter Leg was parallel to the longer, which being hermetically sealed, and so much Water conveyed into the crooked End, that it was of an equal Height in both Legs, so much Air was contained in the Cavity of the shorter Leg, as possesses an Inch and ½. The Instrument being thus prepared, one was ordered to suck at the Top of the longer Leg, and by all the Force and reiterated Suctions, he was not able to raise the Water higher than the Air in the shorter Leg depressed the Surface of that; for when the Spring of that Air was so far weakened, that it could not depress the Water subjacent; the Water kept at the same Station, being not above four Inches high, which was not two Inches and an half higher than at first. But as soon as the External Pressure of the Atmosphere, was again admitted to the Surface of the Water in the longer Tube, it was presently depressed, and the Air in the shorter Leg condensed, till the Water likewise risen in that to its first Station. For a further Confirmation of our Hypothesis about Suction, I shall subjoin Experiments to prove the following Propositions. Our Hypothesis reduced to Propositions. I. That a Liquor may be raised by Suction, when the Pressure of the Air, neither as it hath Weight, nor Elastacity is the Cause of the Elevation. II. That the Weight of the Atmospherical Air is sufficient to raise up Liquors by Suction. III. That in some Cases Suction will not be made, as, according to the Hypothesis I descent from, it should, although there be a Dilatation of the Suckers Thorax, and no danger of a Vacuum, tho' the Liquor should ascend. The first Propositions proved. To make out the first Proposition, I made the following Experiment, viz. I took an inverted Tube, such as was formerly made use of, for a Travelling Baroscope, but something longer, which being filled with Mercury, it was inverted, and the Mercury in the longer Leg stood above the Mercury in the shorter Leg, as high as it usually does in an ordinary Barometer; and then, one was ordered to suck at the shorter Leg, upon which the Mercury subsided in the longer, and rose in the shorter; the Mercury in the longer by its own Weight depressing the subjacent, and raising that, when the equivalent Weight of the Atmosphere was taken off. The second Proposition proved. As for the second Proposition laid down, viz. That the Weight of the Air is sufficient to raise Liquors in Suction; It may easily be proved by Arguments drawn from our Physicomechanical Experiments, and therefore here I shall only take notice of Phaenomena exhibited by our Travelling Baroscope; for having got a Baroscope, whose shorter Leg was something longer than ordinary, we caused one by Suction to raise the Mercury up to the Top of it, and then hermetically sealing it up, we marked the place to which the Mercury had subsided in the longer; which being done, we unsealed the shorter Leg, and observed, that the Pressure of the Atmosphere elevated the Mercury in the longer Leg 5 Inches. The third confirmed. For a further Confirmation of the Doctrine laid down in this Proposition, I shall subjoun the following Experiment. We made use of a Travelling Baroscope, whose shorter Leg was 2 Inches above the Surface of the stagnant Mercury; and having sealed up the End of the shorter Leg, we opened the End of the longer; upon which, the Weight of the Atmosphere being added to the Pressure made by the Cylinder of Mercury, the Air contained in the shorter Leg was compressed into half the Space it possessed before. This Experiment being tried a second time had the like Success. To make it further appear, how much the Ascent of Liquors depends on Pressure. I took a Glass Syphon like the former, and having hermetically sealed up the shorter Leg, I poured in so much Mercury as compressed the Air in the shorter Leg, into half the Space it possessed before; the Mercury in the longer Leg being at the same time, about 30 Inches higher than in the other; nevertheless, the Mercury could not be raised by Suction above one Inch higher in the longer Leg; whereas, did the Ascent of Liquors depend on Nature's Abhorrency of a Vacuum, it would have rose much higher, there being no danger of leaving a Vacuum in the shorter Leg, since the Air was compressed into half the Space it naturally possesses; so that the Reason according to our Hypothesis evidently appears to be this, viz. that the Pressure of the Cylinder of Mercury, and the compressed Air being in a due Aequilibrium, when, by sucking, the Air is drawn out of the longer, the Air in the shorter expands itself so much, as Pressure is taken off by the Removal of that Air, and when it is expanded so far, the Pillar of Mercury keeps it from expanding any further, so that, there being no other Force to raise and press the Mercury up, it can be elevated no higher, since the Air included in the shorter Leg acts only by Virtue of its Spring, and not as in the open Atmosphere, by Virtue of its Spring and Weight too, so when it hath lost its Spring, it can propel the Mercury no higher. To conclude this Discourse, I shall here explain one Phaenomenon in Vacuo Boyliano, which to some seems an Argument of Nature's Abhorrency of a Vacuum. The Phaenomenon is, That if one's Finger be applied to the Orifice of the Pipe, that conveys Air from the Receiver to the Pump, the Pulp of one Finger, will enter a good way into the Pipe, and be very painful; the Protuberant Part of it seeming to be drawn in by Attraction. To which we give this brief Answer, viz. That when first the Finger is placed there, it receives an equal Pressure from the Air within the Pipe, and from the Atmosphere; but when that Air is drawn away, the External Pressure finding no Resistance, presses the fleshy Part into the Tube, which is accordingly painful, as the External Pressure in reference to the internal Resistance is greater or less. To illustrate this Explication, I shall add, that having closed up one End of a Glass Pipe, whose Diameter was an Inch, with a piece of oiled Bladder, and filled it full of Water; it was immersed in a tall Vessel full of Water, the immersed End of the Tube reaching almost to the Bottom of the Vessel, and the other End emerging, and standing open above the Vessel: This being done, we took Water out of the Tube, till the Surface of it was considerably lower than the Surface of the Water in the Glass Body; upon which, the Bladder being more strongly pressed against by the Water in the Vessel, than that in the Tube, the Bladder was forced so much into the Cavity of the Tube, as to form a Semi-Globe; but if, when the Water in the Tube, and that in the Vessel were equally poised, the uppermost Orifice of the Tube were stopped, tho' the Pipe were so much immersed, that the Quantity of Water, which pressed against the lower side of the Bladder, were greater than that in the Tube; yet would not the Bladder have the least Protuberance; but if the Orifice of the Tube were left open to the Air, the Bladder would suddenly be pressed so much into the Hollow of the Pipe, that it's Convex Superficies would represent a Semicircle. The same Experiment being tried with a Tube, the lower End of which was so bend, as to form a right Angle, the Success was the same: Nor did it vary when tried in the strait Pipe, with Wine instead of Water, save that Wine not being specifically aeque-ponderant with Water, a greater Quantity of Wine was requisite to settle them, at first, in a just Aequilibrium; but when that Aequilibrium was lost, by immerging the Tube into the Water, the Bladder was raised, so as to become protuberant in the Cavity of the Pipe. CHAP. VIII. Some Observations and Directions about the Barometer, communicated by Mr. boil, in the Phil. Transact. of April 1666. Observations concerning Barometers. THE Design of trying Barometrical Experiments in several Parts, being only that by comparing Notes, The Extent of Atmospherical Changes, in Point of Weight, might be the better estimated; I shall lay down the following Directions for those, whose Curiosity leads them that way. First, It will be requisite to note the Day and Hour in which Observations are made. Secondly, The Situation of the Place where the Barometer stands as to Height, since by the Length of the Atmosperical Pillar of Air that presses upon it, the height of the Mercury may vary; tho' not always exactly; for sometimes upon Changes in the Air not otherwise observable, the Mercury will subside more than usually in that which stands furthest from the Centre of the Earth, when at the same time it does not proportionably subside in that which is placed in a lower Situation. And It, perhaps, may be Worth Noting, whether upon excessive Droughts, when the Ground is parched and cracked, some subterraneal Effluvia may not rise, which may add a specific Gravity to the Air. Nor will it be needless, when other Observations are making, at the same time to observe the Wether; as also what Winds blow, and whether violent or more remiss; for sometimes it is observed, that when high Winds blow, the Mercury is the lower, tho' not always. But to favour what hath been intimated, viz. That the Alterations in the Weight of the Air, depend on subterraneal Steams mixed with it; It hath been observed, that after long Droughts, upon a Shower of Rain, so many Steams have been either prevented from rising, or depressed and precipitated, that the Mercury hath subsided within 2/16 of an Inch. CHP. IX. An Account of a new kind of Baroseope which may be called Statical: communicated in the Philosophical Transactions of July 2. 1666. A new Baroscope described. HAving caused a Glass Bubble to be blown, as large and thin as it possibly could be; I counterpoised it in a Pair of Scales, which would turn with the 30th Part of a Grain; which Balance being suspended at a Frame, both the Frame and the Balance were placed by a good Baroscope, from whence the present Weight of the Atmosphere might be learned. By which means I could discern Variations, by which the Altitude of the Mercury was not altered above ¼ of an Inch. And it was not a little pleasant to behold, that sometimes the Bubble would be counterpoised; but when the Atmosphere was very high, it would manifestly preponderate, and upon other Changes the Scales would preponderate on the other side, and in some Days time again regain its Aequilibrium; so that by looking first on the statical Baroscope, one might foretell, whether in the Mercurial Baroscope the Water were higher or lower; but of all the Seasons we made our Observations in, the most frequent Changes were in the Spring. This statical Baroscope having exactly answered upon frequent Observations, I shall add the following Notes concerning the Instrument. And first, as to the Grounds on which I proceeded in making this Baroscope. 1. That the Glass Bubble and its Glass Counterpoise are not of the same Bulk, the Bubble being a hundred times bigger than the Counterpoise. 2. If Bodies of equal Weight and unequal Bulks be weighed in another Medium, the Aequilibrium will be lost; for if the new Medium be heavier, the Body whose Dimensions were larger, will be lighter than before; and Vice versâ, and the Disparity of Weight in the new Medium will be greater, as the Inequality of Bulk betwixt the two Bodies varies. 3. These two things being laid together, I considered, that it would be the same thing in reference to the Effects, what Medium these Bodies were weighed in, provided the difference were considerable; and consequently, since the Baroscope made it evident, that the Weight of the Air varied, the Bubble and its Counterpoise would be differently affected upon those Variations, and would accordingly preponderate, the Bubble being subject to preponderate when the Air was lighter; and Vice versâ. Secondly, The Bubble was about the size of a large Orange, and weiged 1 Drachm and 10 Grains. Thirdly, If I had had, any Opportunities, I would have tried whether the Aequilibrium of these two Bodies would have been altered, by the Dryness or Moisture of the Air. Fourthly, When I could not get one Bubble large enough, I have made use of two less, which tho' they are not altogether so convenient, yet, if the Scales be strong enough to bear the Weight, they will answer the Design of the Experiment. This Instrument may be improved by several Accommodations. As, First, To the Ansa of the Balance, an Arch of a Circle may be fitted, which being divided into 15 or 20 Degrees, will readily tell the Quantity of the Angle, and how much the Position of the Cock declines from a Perpendicular. Secondly, A Counterpoise of Gold may be made use of. Thirdly, The Balance being made of Copper or Brass, will in time vary less in its Exactness, than if it be made of Steel, which is more subject to rust. Fourthly, The Bubble and its Counterpoise may be suspended at the Beam, by which means it will be less burdened with Weight. Fifthly, The whole Instrument will be more free from Dust and irregular Agitations, if placed in a Frame, like a Square Lantern, with Glass Windows and a Hole at the Top to give an Intercourse betwixt External and Internal Air. Sixthly, This Instrument having a light Wheel and an Index fitted to it, such as Dr. Wren used to open Weather-Glasses with, and the Ingenious Mr. Hook, applied to Baroscopes, will discover more minute Variations. Seventhly, The Beam may be improved by being made longer, and its Balance may be more exquisite than those I generally employed. Thus, tho' this statical Baroscope be inferior to the Mercurial one in some Respects, yet in others it is more convenient; For First, It demonstrates to autopsy, that the Ascent and Descent of the Mercury, depends on the varying Weight of the Atmosphere; since here it cannot be pretended, that the Changes depend on a Fuga Vacui. Secondly, It shows that the Air hath Weight, and much more than some Learned Men would allow; since in so small a Quantity of it, we see considerable Variations. Thirdly, It is more easily, provided; and more conveniently removed. Fourthly, We are more easily satisfied of the Goodness of them. Fifthly, The Absolute or Respective Weight of the Air may more easily be discovered; if, when the Weight and Dimensions of the Bubble is Hydrostatically discovered, upon every Alteration of the Mercury's Height in the mercurial Baroscope, the statical Baroscope's Aequilibrium be restored by the Addition of Weights; that Weight in the statical Baroscope answering the Variations in the Ascent or Descent of the Mercury in the other. Sixthly, By this Instrument, we may compare the mercurial Baroscopes of several Places, and be able to make some Estimate of the Gravities of the Air therein; for, if in one place the Bubble weighs a Drachm, when the Mercury is 29 ½ Inches high, and that when the Mercury is risen an 8th, it is requisite to add the sixteenth Part of a Grain to preserve the Aequilibrium; When I come to another Place, and find the same Proportions answer, I may conclude, that there is no sensible Difference in the Weight of the Atmosphere in those Places; but if an additional Weight be required to preserve the Aequilibrium, than the Air is so much heavier, than when the Mercury stood at 92 ½ Inches. But in making these Observations we must take notice, whether the Places in which they are made, are equally distant from the Centre of the Earth; for if one be a Valley, and the other a Hill, there will happen a difference upon that Account. There is yet another use which may be made of this statical Baroscope, which is, to discover the Weight of the Atmosphere at the Top and Bottoms of high Mountains; but whether that may contribute to the discovering the Height of Mountains, or not, I shall leave to be considered with more leisure. CHAP. X. A Discovery of the Admirable Rarefaction of the Air, even without Heat. FROM what hath been delivered amongst our new Physicomechanical Experiments, it appears, that long since I could, by the help of my Engine, rarify the Air to 152 times it's usual Dimensions; and the Virtuosos of the Florentine Academy tell us, that they would rarify it, without the help of my Engine to 173 times it's former Dimensions; Yet for further Satisfaction, I made the following Trials. EXPERIMENT I. Air expanded to above 8000 times it's natural Dimensions. HAving filled a round Glass Egg of clear Metal, and furnished with a Pipe some Inches long, with Water; this, together with a Viol, in which Water was likewise contained, was conveyed into a Receiver; and when the Air was exhausted, we observed, that Bubbles were afforded plentifully in both, so that the Water seemed to boil, and that in the Stem of the Glass Egg ran over. This being done, and the Water in both freed from Air, we took them out, and filling up the Stem of the Glass Egg, with Water out of the Bottle, we inverted it into more of the same; so that the Glass Egg and Stem was wholly full, except that a Bubble of Air was contained in the Top of the Egg, whose Dimensions were a Tenth and less than two Centesms of an Inch. Then the Glasses being placed in the Receiver, we set the Engine on Work; and observed, that the Bubble gradually expanded, till it filled up the whole Capacity of the Egg, except the Stem; and lest the Water should be thought to subside only for want of the Internal Air to bear it up, we continued pumping, till the Bubble in the Egg expanding further, depressed the Surface of the Water in the Stem, below the Surface of the External Water. The Air being thus far rarified, we compared the Diameter of the Bubble with the Diameter of the Glass, and found it to be as 1 to 20; and consequently, according to Euclid, the Proportion betwixt Spheres being triplicate to that of their Diameters, the Diameter of the lesser being one, the Diameter of the other must be 8000. So that the Air expanded, possessed 8000 times the Space it possessed before. The Glass Egg being filled with such Water again, and no Air included in it, tho' the Receiver was in a great measure exhausted, yet the Water did not subside, till a Bubble at the last rose to the Top, whose Diameter was to the Diameter of the Glass as 1 to 14, so that according to Euclid's Rule beforementioned, the Bubble expanded, possessed 2744 times as much Space as before. But Dr. Wallis, observing the great Thinness of the Glass, thought that the expanded Bubble possessed 8232 times it's former Dimensions. N. B. Water being let into the Exhausted Receiver, till it would receive no more; we found, that by reason of some Leaks, the Receiver had not been perfectly exhausted. EXPERIMENT II. June 2.62. Air expanded to 10000 times it's former Bulk. ASmall Bolt-head, which was able to contain 80 Grains of Water, being inverted into a Jar, it was shut up in the Receiver; and when the Air was exhausted, Bubbles which risen out of the Water expanding themselves, presently drove all the Water out of the Bolt-head; but when the Air was let in again, the expanded Air in the Bolt-head formed a Bubble no bigger than a Pin's Head: After this, we filled the Bolt-head with Water cleared of Air, and when the Receiver was pretty well exhaufied, a Bubble ascended to the Top of the Bolt-head, which, when the Air was again let in, was almost invisible; yet the Receiver being again exhausted, it expanded itself so far as almost to drive all the Water out of the Bolt-head; yet when the External Air was again admitted into the Receiver, it shrunk into a Bubble, whose Diameter was 1/22 part of the Diameter of the Bolt-head, so that to fill the whole Cavity it expanded itself 10648 times; but considering the Cavity of the Neck of the Vessel, which it likewise in some measure filled, it was expanded to 13769 times its Bulk. The Diameter of the small Bubble retracted, was 1/27 of an Inch. The Diameter of the outside of the Head of the Glass was 29/36 of an Inch. The Water that filled the Head was 60 ½ Grains. The Water that filled so far of the Neck, as the expanded Bubble possessed was 17 ½ Grains. The Bolt-head weighed 15 Grains. EXPERIMENT III. THE foregoing Experiment being repeated, we found that a Bubble, whose Diameter was 1/16 of an Inch in Diameter, when expanded, possessed the whole Space of the Ball, as well as Neck of the Bolt-head, and depressed the Surface of the Water within the Pipe, below the Surface of the stagnant Water. From these Experiments it appears, that according to the most moderate Estimate, Air expanded will possess 2744 times it's natural Space, and according to our most successful Experiments 13000. So that we may justly admire the Minuteness of those Aerial Instruments, that she employs even about Visible Operations. CHAP. XI. New Observations about the Duration of the Spring of Expanded Air. Observations about the Duration of the Air's Spring. IT having not been as yet attempted to show, whether a Portion of expanded Air, would retain its Elasticity, and its Power of Restitution or not, nor how long; nor whether a Portion of Air enclosed in a Receiver, would have its Spring varied upon Full, or the Change of the Moon; tho' I cannot much boast of the Progress I have made, yet I shall subjoin the following Attempts on that Occasion. A Glass Bubble newly blown, and whilst it contained none but rarified Air, had its Stem immediately clapped into a Flame, and Sealed up; Many Months after it was inverted into a Basin of Water, and the Seal broke off under the Surface of it; and tho' Water was violently impelled into the Cavity of it, yet the included Air had so far retained its Spring, as not to suffer the Cavity to be quite filled with Water. Another Method I took to show the Durableness of the Air's Spring was the following, viz. Leaving a small Portion of Air in the Folds of a Lamb's Bladder, whose Neck was closely tied; it was enclosed in another Vessel, and conveyed into our Pneumatick Engine, and when the Receiver was exhausted, the expanded Air distended the Bladder, so that it filled the whole Cavity of the Vessel, by whose sides, it was guarded from the Pressure of the outward Air, so that the expanded Air kept the Bladder distended two Years. For further Satisfaction, I contrived an Instrument, by which I could learn, whether, and how long Air variously expanded will retain its Spring; by which I could not discover, that the Air lost any thing considerable of its Spring, in ten Weeks time. Another Instrument I made use of, by which I could find, that Air expanded to 1000 times it's usual Dimensions, would be sensibly affected by Heat, and lose the Expansion it gained thereby, upon a Removal of that Heat. March 18. We tried the following Experiment. A Cylindrical Glass having a long Stem at the unsealed End, was filled with Water, and inverted into Water, which lay in the bottom of a large Pipe, sealed at one End, and 3 or 4 Foot long; which being done, the large Pipe was so far exhausted, that the Air the inverted Pipe possessed the whole Cavity of it down to the Stem; upon which the larger Tube being closed up, the expanded Air possessed the same Space 3 Months after, except that betwixt the Pipe and the Stem, upon extreme Cold, the Water risen ⅛ or near ¼. The closed Apex being broke open under Water, it gradually filled the whole Cavity, except a small Space possessed by a little Bubble. The Diameter of the Cylindrical Part of the Pipe was ⅗ of an Inch, and its Length 3 Inches; the Bubble was about 2/10 in Diameter, and 2/100 in Depth; so that the Bubble was, according to Dr Wallis his Computation, to the Space it possessed, when expanded, as 1 to 1350. CHAP. XII. New Experiments touching the Condensation of the Air by mere Cold, and its Compression without Mechanichal Engines. Of the Air 's Condensation by Cold, etc. TO try how far the Air is capable of being condensed by mere Cold, when the Season of the Year hath not pre-affected it; I tried the following Experiment in Autumn. In the middle of September about Noon, on a Sun-shiny Day, we placed a Bolt head in a Frame, so that the Stem was Perpendicular to the Horizon, and the lower End of it immersed in Water. This done, we covered the Ball of the Bolt-head with a Mixture of beaten Ice and Bay-Salt; upon which, the internal Air being condensed, the Water risen up into the Stem, and stood a good while: Then having made a Mark at its highest Station, we filled the Vessel with Water, and found that it yielded ℥ 19 and ʒuj, the Weight of the Water which filled the Stem up to the Mark being ℥ j and ʒiij, by which Number, the former being divided, the Quotient was 14 4/11 Drachms; so that the Proportion of the two Quantities being as, 11 to 158; The Space into which the Air was condensed, was, to it's former Space, as 147 to 158: So that the highest Degree of Condensation it was then capable of, made it lose of its former Extent 11/158. N. B. First, The Stem of the Glass ought to be long, lest the Water, upon the Air's Condensation, should rise into the Ball of it. Secondly, The Cylinder of Water was two Foot, so that it might, by its Weight, in some measure, hinder the Ascent of more, and so keep the Air from condensing to its utmost. Thirdly, When the Water risen as high as it well could, we observed it to rise and fall alternately, for a little time. Fourthly, The Air may thus be further condensed, than by Winter's Cold. But to show that in the foregoing Experiment, the Cold did not compress the Air immediately, but partly, in as much as it, by stuffing up the Pores of the Water, caused it to swell, and so to compress the Air; I took a new Glass Bolt-head with a short Neck, and filled it full of Water; so that when it was hermetically sealed up, the Liquor wrought within 3 Inches of the Top, the sharp End which was made for the Conveniency of sealing being ¼ of an Inch long; This being done, the Bolt-head was placed in a Mixture of Snow and Salt, upon which, the Water ascended and compressed the Air into the Conical Part; upon which, the Glass flew in pieces. In which Experiment, according to Dr. Wallis his Estimate, the Air was compressed into a 40th part of the Space it possessed before. Which is considerable above the utmost Compressure made in Windguns, where it is usually thought not to be compressed into less than a 15th, and (according to Mersennus) into an 8th part of its former Space. CHAP. XI. Of the Admirably differing Extension of the same Quantity of Air rarified and compressed. The admirable different Extensions of the same Quantity of Air. THE first Thing I shall take notice of, concerning the different Degrees of the Air's Rarefaction and Condensation, is, That, in our Climate, tho' Cold will not condense it near into a 20th part of the Space it possessed before, yet it may be expanded to 70 times that Space. Secondly, The Air may be much more condensed and rarified by our Engines, than by Heat or Cold; the Proportion in respect of Expansion being as 1 to 70. But, Thirdly, Perhaps the Proportion betwixt the Degrees of the Air's Condensation and Rarefaction will not be thought so great, as what we have mentioned; if we consider, that the Air we make Experiments with here below, is so much compressed already, by the Incumbent Atmosphere, that for that Reason it is more inclined by its Spring to yield to an Expansive, than a Compressive Force. Fourthly, It may be questioned, how the parts of the Air, which have a specific Gravity, come to be spread so thin in the Cavity of the exhausted Receiver, since there is nothing in it for them to swim in, and to bear them up; Since the Proportion is so great betwixt the Parts of the Air, and the Cavity of the Receiver, they are contained in. Fifthly, It is not a little wonderful, that Air should be so subject to vary its Dimensions; so that if we consider how far it may be expanded without the Assistance of Art, elaborate Engines or Heat, the Top of the Atmosphere must be extremely rare. To conclude; If we compare the utmost Degrees of Condensation and Rarefaction together, the same Portion of Air may possess 520000 times the Space, at one time, that it did at another. CHAP. XII. New Experiments about the weakened Spring, and unheeded Effects of the Air, communicated in the Philos. Transact. of Decemb. 75. TO try whether, as some Corrosions of Bodies in close Vessels increase the Spring of the Air, so others may not weaken it; and likewise to discover whether some Effects of the Air may not depend on some unheeded Qualities, I made the following Experiments, which I shall lay down when I shall have made some Trials. the Changes of Colour in Solutions of Copper, by the Influence of the Air. EXPERIMENT I. Change of Colour in a Solution of Copper. FILINGS of crude Copper being put into a Crystal Glass of a Conical Figure, with as much Spirit of Salt, as stood a Finger's breadth above the Filings; we covered the Vessel with a Stopple exactly adapted to it; upon a Solution of the Copper, the Colour of the Liquor was a dark Brown; but it soon lost that Colour, and was clear again like common Water; but when, by taking out the Stopple, the Liquor was again exposed to the Air, it first acquired a brown Colour upon the Top, and that penetrating deeper into the Liquor by degrees; it, in a quarter of an hour, was wholly tinged with a brown Colour again; and so it successively laid down, and re-acquired that Colour, as it was stopped up, or exposed to the Air, till at the last, being kept up a Month, it kept the brown Colour it had acquired in the Air unalter'd. EXPERIMENT II. A Bottle of the same Liquor with the former, and which was much clearer, being exposed to the open Air, in half an hours time was not in the least altered; but the Vessel being again closed up for two or three hours, it acquired a faint Green; and the Glass being again unstopped 24 hours, the Green was deep enough, but not very transparent. EXPERIMENT III. ABout 3 Spoonful of the brown Tincture of Copper, was shut up in a Receiver, capable of holding ten times as much; It retained its Colour half a Year in Vacuo, and then being exposed to the Air, it acquired a Green in about an hour, without the Precipitation of any muddy Sediment. EXPERIMENT IU. SOme of the aforementioned Tincture being left a considerable time in a Window, lost its Colour, and appeared like common Water; but towards the latter end of December, being exposed to the Air, it acquired a faint and moderately transparent Green. EXPERIMENT V. Filings of Copper and Spirit of Wine. FILINGS of Copper, and as much rectified Spirit of fermented Urine, as risen an Inch above them; being shut up in a Conical Glass with a mercurial Gage, in some hours the Mercury in the sealed Leg was depressed. EXPERIMENT VI. A Gage being shut up in a Receiver, with the same Ingredients as in the former Experiment; In some time the Spirit acquired a very pleasant blue Colour, and two or three Days after, that Colour began to grow fainter and fainter; so that at the end of the fourth Day, it had wholly lost its Colour: But being exposed to the Air, in four or five Minutes the Top of the Liquor began to turn Blue, and at the end of ten Minutes, it diffused itself throughout the Whole, and five Minutes after, grew so strong, as almost to be Opacous. The Liquor shut up again, in two or three days time grew clear. And this Experiment being tried several times, had the like Success. In trying these Experiments, I forbore to shake the Glass, lest the Alterations should be supposed to arise from any Sediment raised and mixed with the Liquor, tho' for the most part, none was to be perceived. EXPERIMENT VII. Filings of Copper with Spirit of Sal Armon. HAving enclosed Filings of Copper with Spirit of Sal Armoniac, enough to cover them an Inch, we shut up, with them, a Gage; In some time, the Spirit had got a blue Colour, and in the mean time, for two or three Days the Mercury in the sealed Leg descended near 1/● of an Inch. The like Success we had, when the Experiment was tried several times after. EXPERIMENT VIII. Coral and Spirit of Vinegar. A Mercurial Gage with Coral and Spirit of Vinegar, being enclosed in a Conical Glass, whilst the Menstruum worked on the Coral, several Bubbles were produced, which breaking in the Cavity of the Vessel, compressed the Air into ⅔ parts of the Space it possessed before; but after the Operation of the Menstruum was ended, the Compression declined, till the compressed Air regained its Extent within a third of what it was dispossessed of by the Compression. Spirit of Vinegar and Minium. Spirit of Vinegar and Minium, being after the like manner enclosed with a Gage in a Conical Glass, tho' the Minium was in a great measure dissolved, yet the Gage, discovered no Alteration in the Air. EXPERIMENT IX. Filing of Copper with Sp. of Sal Armon. ABOUT the 20th of August we put Filings of Copper into a Viol, with as much Spirit of Sal Armon. as covered them an Inch; In three Days it had acquired a deep blue Colour, and almost lost it again: The Viol being opened, in five Minutes it was of a deep Blue; but being shut up again nine Days, it lost its Colour. EXPERIMENT X. THE same Ingredients being shut up in a Viol hermetically sealed, presently acquired a deep Blue, and in twelve Days after lost it again; during which time, the Mercury in the open Leg was impelled up; but, when in the Night the Seal was broken open, there succeeded a Noise, and the Mercury in the shorter Leg was raised briskly near 3/● of an Inch; and tho' the Air had access to the Liquor, at an Orifice no larger than a Pea; yet, in a Minute and a half, the Surface of the Liquor had acquired a lovely fair Colour a quarter of an Inch deep; and in five Minutes, the whole was Blue. CHAP. XIII. A Statical Hygroscope proposed to the Secretary of the Royal Society. COnsidering how much Men's Bodies are influenced, by the Moisture of the Air and its Dryness, I made use of the following Hygroscope to discover the different Degrees of those Qualities, viz. A Sponge; which is a Body that sucks up the Air's Moisture much more commodiously than several other Bodies; for tho' common Sea-Salt or Salt of Tartar will imbibe the Moisture of the Air, yet it is a hard matter to separate it from them again. And tho' Lute-Strings discovered the Degrees of the Air's Moisture by the increase of their Bulk, yet they continued not to answer Expectation long. I likewise made use of a Cup, made of a Light Wood, with a Button on the Bottom of it, to which a Hair being tied, it was, by that, suspended at a Balance; and also, I observed several things, when I made use of Sheep's Leather, which would be a good Hygroscope, being plentifully furnished with Pores to imbibe Moisture, but that it is more subject to Rot than Sponge. A statical Hygroscope. For in the main, I found nothing so convenient as Sponge, which is so plentifully stocked with Pores, that a Drachm, having imbibed as much Water as it could contain without dropping, weighed 2 Ounces and 2 Drachms; And All that is required in using this Hygroscope, is, that the piece of Sponge made use of, be first weighed in Air of a moderate Temperature, with a Nice Balance; for as afterwards it increases or decreases in Weight, so accordinly the Air is moister or drier. In making use of this statical Hygroscope, you may use what Quantity of Sponge you please, so that its Weight be not so great as to injure the Balance. CHAP. XIV. A Brief Account of the Utilities of Hygroscopes, The Usefulness of Hygroscopes. THE Use of a Hygroscope is either General, or Particular; The general Use is, to estimate the Changes of the Air, as to Moisture and Dryness, by ways of measuring them, easy to be known, provided and communicated. This appears from the Description of our statical Hygroscope; by which, we can by the help of small Weights, discover the least sensible Alterations in the Temperature of the Air; nor is it the only Advantage in our Hygroscope, that it is able to discover such Alterations in the Air's Temper, but it is an Additional one, that it is durable and lasting. N. B. It is one great thing wanting in the Preparation of Hygroscopes, that we have not yet found a Standard of Moisture and Dryness to adjust and compare other Hygroscopes by. But having thus briefly intimated the most general Use of Hygroscopes, I shall now proceed to mention their Particular Uses. USE I. To know the differing Variations of Wether in the same Month, Day and Hour. I Have commonly observed, that when the Wether was at a stand, the Sponge grew heavier in the Night, but lost that Moisture the next Day, before Noon; but in frosty Nights, at the latter End of the Winter, this Observation did not hold. Amongst other Observations, it would not be amiss to note, whether there be any Correspondence in the Air's Operation on Hygroscopes and Baroscopes; and if at all, in what kind of Wether. For usually in the Summer, when the Hygroscope is lightest, the Baroscope is higher, tho' strong Winds may make both lighter, such as the North-West with us; whereas South Winds with Rain usually make the Baroscope lighter, and the Sponge heavier. And East Winds, tho' they make the Baroscope heavier in Winter, yet they make the Hygroscope lighter. It would likewise be of use to observe on the Sea-Coast, whether the Ebbing and Flowing of the Sea, causes any sensible Alteration in the Hygroscope, as likewise at what time the Air is moistest; especially at Full and New Moons; by which Observations we may more easily hope to determine, whether the Moon diffuses a Moisture through the Air or not, than by observing the Plumpness of Oysters and Shellfish, or of the Brains or Marrow of Animals, which is a hard thing to be sure of. To these Observations it will be requisite to note, whether upon Spring-Tides in March or September, the Hygroscope receives any sensible Alteration. USE II. To know how much one Year or Season is drier or moister than another. IF the Hygroscope when it continues longest without some sensible Alteration, Use 2 be taken for a Standard; by comparing Observations made at other Seasons of the Year, and in other Years, it will be easy to learn how much one Year is moister than another. How much these Observations may be of Use to Physicians, where Distempers arise from too much Moisture or Dryness, and to Husbandmen and Shepherds in ordering their Corn, and removing their Flocks, from too moist Ground, I shall leave undetermined. But in order to make Predictions, it will be necessary to Register the Number, Bigness and Duration of the more considerable Spots, that appear or are dissipated near the Sun; and what Alterations happen to the Hygroscope at such times. Nor would it be amiss, to observe what Alterations happen upon Eclipses of the Sun and Moon, or great Conjunctions of the Planets. USE III. To discover and compare the Changes of the Temperature of the Air made by Winds strong or weak; frosty, snowy and other Wether. THAT the Sponge in the Wind or Sun loses considerably of its Weight, Use 3 I myself have experienced, a Sponge hanging in the Sun in January, having lost a 24th Part of its Weight, after it had been 3 quarters of an hour exposed to it; and making use of half an Ounce of Sheep's Leather instead of Sponge, this being hung in the Wind, only lost 1/18 of its Weight in an hour. But tho' it be possible thus to make Observations of Particular Winds; yet it requires a great deal of Caution, as well as Skill in Physic and Cosmography, in forming Rules for the observing of the Qualities of other Bodies, since Winds which come from the same Quarters in several Countries have different Qualities; for tho' North Winds in the Winter, are generally attended with Frost, yet at the Famous Port of Archangel a Thaw accompanied it; the Reason of which seems to be no other than, that the Northern Wind coming a long way over the Northern Seas, does not acquire such a Disposition as the South Wind, which passes over a large Tract of Frozen Land. And it is observed in Egypt, that the North Winds which are elsewhere drying, are there moist, which is attested by Mr. Sands in his Travels into Egypt, lib. 6. Cap. 8. Sect. 3. And Monsieur de Serres affirms, that about the Quarters of Tholouze, the South Wind dries, and the North Wind brings Rain; yet from Narbonne to Lions, all over Provence and Dauphinè it is quite otherwise. But, besides that on this account Winds from the same Quarters may differently affect the Hygroscope; It's Operation may be considerably diversified, as it blows vehemently or slowly over the same Country; for though Wind would rather increase the Weight of a Hygroscope if moved slowly, yet by a more vehement Agitation, several moist Particles in the Sponge are dissipated and dispersed. To these Observations I shall add the following, Viz. that frosty Wether hath been observed to make the Hygroscope grow lighter towards Night, and that snowy Wether increased the Weight of it, as likewise misty and foggy Wether. But what is more strange is, that on a Sun-shiny day, the Sponge hath preponderated upon the passing by of a Cloud; but as soon as that was gone, regained its Aequilibrium; and I have observed, that when the Air hath grown heavier, the Hygroscope hath grown lighter, as if those Terrestrial Effluvia which increase the Weight of the Air were unfit to be imbibed into the Pores of the Sponge; wherefore at such times it may not be amiss to take notice; whether any, and if any, what kind of Meteor, as Wind, or Rain or Hail, or in the Winter, Snow or Frost, will commonly be signified or produced. USE iv To compare the Temperature of differing Houses, and differing Rooms in the same House. THIS may be of considerable Service in enabling Men to choose Rooms, Use 4 which may be most consistent with their Health; for the difference in some Rooms hath been observed to be so considerable, that a Drachm of Sponge hath acquired the Additional Weight of 3 Grains and ⅛, and upon a removal into another, hath lost 1 Grain and ⅛, tho' in a rainy Night. And a piece of Sponge that wanted 4 Grains and ¾, being removed into another Room near a Fire, in a short time, wanted but 1 ½ Grain, and the next Evening after this Observation was made, it weighed ʒj 1 Grain and almost a half: The next day it exceeded a Drachm above 2 Grains; but about 4 in the Afternoon the Wether growing frosty, it lost of its Weight; and a Drachm of Sponge that was kept in a dry Room upon foggy Wether, being removed, in a Night's time, gained 11 Grains, and in the Morning being removed into the former, it gained 2 Grains. USE V. TO observe, Use 5 in a Chamber, the Effects of the Presence or Absence of a Fire in a Chimney or Stove; which will sensibly appear by the help of our Hygroscope. USE VI To keep a Chamber at the same Degree, or an assigned Degree of Dryness. THIS may easily be done by observing the Aequilibrium of the Sponge, Use 6 and accordingly increasing or diminishing the Fire. I have observed a notable Difference in the Weight of a Hygroscope, when the Room hath been washed, though a good Fire was kept in it to dry it presently. To these Observations I shall add, that I have sometimes taken notice, that the Hygroscope hath not answered our Expectation, as at other times; whether the Air, at that, abounded with other Effluviums, which rendered the moist Particles of it, more unfit to be imbibed by the Pores of the Sponge, I shall not determine; nor whether in time, Hygroscopes may not help us to discover the Nature of different Effluviums, such as those of Spirit of Wine, Chemical Oils, etc. Nor shall I undertake to determine, whether this Instrument joined with the Baroscope and some others, may not help to give us a foresight of some Constitutions of the Air which precede Diseases, Hurricanes, Earthquakes, or Inundation; especially of those Accidents which depend on the Air's being overcharged with Exhalations and other moist Vapours; as well as it does of a shower of Rain. To conclude this Chapter, I shall intimate, that tho' in these Matters it be perhaps impossible to form Hypotheses, which can in no Points be called in Question, yet the Theory may be as good as can, by a wise Man, be expected, in so mutable a Subject as the Air; and therefore they ought not to be slighted or suddenly laid aside, since several Accidents may intervene in the Air, on which those may depend. As we know, tho' Tides generally Ebb and Flow, so as to answer the Theory given of them, yet by fierce Winds and great Land-Floods, the regular Course of them hath often been altered. CHAP. XVIII. A new Experiment and other Instances of the Efficacy of the Air's Moisture. The Efficacy of the Air's Moisture. THAT the Moisture of the Air hath had considerable Effects on Subjects far less tender and curiously contrived, than Men's Bodies, will appear from what follows; and that the Moisture of the Air hath a considerable Influence,, and usually a bad one, may well be argued from the Effects we have taken notice of on several Parts of Animals; and that the Skins of Animals are sufficiently prepared to receive such Effluviums, appears from what I have before observed, viz. That Sheep's Leather being made use of for a Hygroscope, plentifully imbibed the Moisture of the Air; and even Bladders which by Nature are made impervious to Urine, are so disposed to imbibe the Moisture of the Air, that the membranous Part put into a Pair of Scales, and counterpoised, makes a good Hygroscope; and not only these, but Lute-strings, which are made of the twisted Guts of Animals, and even Bones, the most solid Parts of Human Bodies, will so far imbibe the Moisture of the Air, as to swell considerably. Nor are Animal Bodies alone capable of having their Pores penetrated by the Moisture of the Air; but it insinuates itself into inanimate Bodies, and swells the solid Parts of Wood; and even Polished Marbles are observed to be so plentifully stocked with moist Vapours, as evidently to sweat; nay even the Air itself is not without Vapours and moist Parts, dispersed through it in the Heat of Summer, which will appear from the following Experiment. Having filled a Bottle with Water and four Ounces of Sal Armon. we counterpoised it in a Pair of Scales, and in an Hours time, so many moist Particles in the Air were condensed by this frigorifick Mixture, that, they first appeared in the form of a Dew, on the outside of the Glass, and then ran down the sides of the Vessel, till that Scale preponderated and weighed a Drachm more than the other. But to proceed to Instances, which, show the Force and Efficacy of moist Vapours, when they penetrate solid Bodies. It is no weak Argument of their Efficacy that we observe, that, by the powerful Insinuation of Moisture, the Strings of Musical Instruments are swollen and broken; nor is it in considerable, that Doors and Door-Cases are so swollen in Rainy Wether, as to open and shut with a great deal of uneasiness. Marchasites burst by the Air 's Moisture. Besides which Instances, I have observed a Piece of Wood to increase considerably in its Weight in rainy Wether: And I am told, it is usual for musical Instruments to grow out of Tune, not only the Wooden, but the Metalline Pipes of Organs being apt to swell in wet Wether. And not only by the help of Rain, but the Moisture of the Air, Marchasites have been swollen and burst asunder; which I am apt to believe, because I have observed Vitriolate Efflorescences upon the Surfaces of shining Marchasites, caused by the Action of external Moisture on them; and the Moisture of the Air hath so powerfully penetrated some Marchasitical Substances, that they have burst asunder; whereupon it appeared, that a greater Quantity of Vitriol was generated within their Substances, than without. To conclude what I have to say on this Subject, I shall add the following Experiment to assist a Virtuoso, to make an Estimate in known Measures of the mechanical Force of the Aerial Moisture. I caused a Rope about 22 Yards long, to be fastened at a convenient Height, to an Body; and then having fixed a Poultry to another stable Body, about 18 Yards distant from the former, the Rope lying upon the Poultry, was, betwixt both, almost in an horizontal Posture; but to that End of the Rope, which hung down from the Poultry towards the Ground, was fixed a Weight of 50 Pound, and to the upper Part of that, an Index, which being placed horizontally, pointed to a Board which was divided into Inches and parts of Inches, that we might discover the better, the Ascent and Descent of it upon changes of Wether. When the Weight had stretched the Rope as much as it could; I observed, that in one rainy Night the Weight was raised five Inches; but the next Day proving a dry Day, it was depressed lower than before. But a heavier Weight being made use of instead of the former; June 4th in an hour and quarter, the hundred Weight was raised ¼ of an Inch. The Sky being cloudy, but without Rain. June 6th. In the Night which was cloudy, it was raised about 3 Inches, and an hour after that Observation was made, it risen half an Inch more. From whence it appears, that the Force of the Air's Moisture is considerable, since the Rope that, by its Assistance, raised the Weight, was but about the third Part of an Inch Diameter, being 3/10 and 4 decimal Parts of 1/10. CHAP XIX. Of some unheeded Causes of the Insalubrity and Salubrity of the Air, etc. The Insalubrity and salubrity of the Air depends on subterraneal Vapours▪ AMongst the several Causes, on which the Salubrity and Insalubrity of the Air depend, subterraneal Effluvia are in Effect most considerable; which differ not only according to their respective Natures, but according to Place and Time; according to Place, as they ascend from the superficial or deeper Parts of the Terraqueous Globe; according to Time such as ascend daily, and may be termed ordinary Emissions, or only at distant times; the latter of which may be termed periodical, and sometimes fortuitous or irregular. But notwithstanding the Vapours which rise from the Earth, may be distinguished by these Distinctions; yet since Nature offers her Phaenomena not so distinct, but confusedly and together, I shall sometimes consider the Terraqueous Steams, in the more general Notion, with reference to each of the Members of this Distinction. But that I may deliver what I have to say more distinctly, I shall lay it down in the following Propositions; Proceed under the following Propositions. having first observed, that the Insalubrity of Marish, and the Salubrity of Sandy Grounds, may depend on some Effluvia, which act not merely or principally as they are Moist or Dry. PROPOSITION I. THE first Proposition is, Prop. 1. That it seems probable, that in divers places, the Salubrity or Insalubrity of the Air considered in general, may be in good part due to subterraneal Expirations, especially to those I called ordinary Emissions. Which may contribute to the preserving of Health either by promoting Respiration, or by correcting noxious Particles in the Air, and checking morbific Ferments. And indeed, if we consider what a great variety of Bodies, besides Minerals, the Earth is stocked with, tho' some may emit Effluvia noxious to Men as well as Plants, yet in that Variety there may not be a few, whose Exhalations may be as friendly to him; for Trees and Grass have not only been observed to flourish over Tin Mines in the West of England, but over Veins of another kind of Mineral, which was not far from the Surface of the Earth. And it is observed, that those that Work in Tin Mines, usually live very long. And I have not only been told, that the Fumes that rise from such Mines, tho' often very bituminous, and of an offensive Smell, yet some of them are well scented: And a Friend of mine, who caused himself to be let down in a subterraneal Cavern, which was broken open by digging for a Mine, not only observed, that the Air was very pleasant to breath, but likewise amongst several imperfectly formed Minerals, store of a Mineral Earth very fragrant and pleasant, which Smell it in some measure retained, when it had been exposed to the Air for some time. And I myself have observed in Ireland, a piece of Ground to yield very good, tho' short Grass, in a Country justly esteemed healthful, which I attributed to some sulphureous Exhalations-from Limestone; which have had so considerable Effects in other places, that I am told that a piece of Ground in Derbyshire which lies upon Limestone, is so warmed by the Vapours that rise from it, that Snow is much sooner Thawed upon it, than that which lies near it, on Soil which covers Freestone. To which it may be added, that a Gentleman observed in Hungary, that walking over some Ground which affords that Noble Oar called by the Germans Rot-gulden ertz, the Air was very pleasant, nor was the Air much less pleasant on that Ground which lay upon Veins of Cinnabar; yet over other sorts of Mines the Air was very inoffensive. Nor is it improbable, that subjacent Fossiles should influence the Air, since I have observed Mineral Earth's twenty Foot deep, yield a volatile saline Spirit, like that of Hartshorn. And that several Effluvia may impregnate the Air, which are not to be discerned by any of our Senses, appears from those Magnetical Effluvia of the Earth, discovered by the Ingenious Gilbert and others, which do not only steam through the Air, but as I have observed, act upon Bodies in an Instant, which are contained in Glasses hermetically sealed. But tho' from hence it may appear, that the Salubrity of the Air may be improved by the Effluvia of some Minerals; yet it is beyond doubt, that in general they render the Air Insalubrious, since there are a great many more that emit bad, than good ones: For besides that the Air hath been observed in Hungary to be very offensive and prejudicial to Respiration, that in the Neapolitan Grotta de Cani, suddenly deprives Dogs both of Sense and Motion. To which may be added the Averni in Hungary, which suddenly kill those that draw in the Air infected with them. Besides which, there are a great many noxious Effluvia which rise from Marchasitical Minerals, which we take little notice of, and in places which we little suspect them to be in; nevertheless, they infect the Air, and render it corrosive, by emitting that ill conditioned Sulphur, which they so much abound with, that a pound distilled in an Earthen Vessel with a good Fire, besides an inflammable Sulphur, which was condensed into thin Films on the side of the Receiver, yielded a strong Acid, not much unlike Gas Sulphuris, which was corrosive enough to dissolve Coral in the Cold. And that there is other Marchasitical or Vitriolate Matter in England, besides those Stones, from which the greatest part of Vitriol is obtained, I myself am a Witness, who have obtained a Vitriol from a Vein of Metalline Oar, consisting of a black, heavy Stuff, without any troublesome or artificial Preparation. PROPOSITION II. It is probable, Prop. 2. that in divers Places some Endemical Diseases do chief or partly depend on subterraneal Steams. UNder the Title of Endemick Diseases, I not only comprise those that are solely peculiar to some Places, as the Plica Polonica to Poland, and the Disease in France called lafoy Colique de Poictou, but those that chief appear in particular Countries, as Agues in Kent and Essex Hundreds, Consumptions in England, and Fluxes in Ireland. But before I proceed further under this Topick, it is requisite I should first Advertise, that I deny not but that a great many of such Distempers may depend in a great measure on Excessive Heat or Cold, or some other manifest Qualities of the Air, as also bad Diet, or Intemperance; but the Reasons why I think they generally in a great measure likewise arise from some noxious and contagious subterraneal Effluvia, are the following. 1. Because frequently the Causes are not manifest; and 2. Contagious Effluvia may be emitted. 3. A large Tract of Land may abound with the same kind of Mineral, and another piece of Land with another. 4. As the Effluvia are Saline, Sulphureous, Antimonial, Arsenical, or of another Nature, they may have different Effects; so in Hungary, some cause a difficulty of breathing. But the Effluvia of the Earth, do not only affect the Body by the Mediation of Respiration, but being contiguous to the Skin, get in at the Pores of the Body, and have sensible Effects on the Internal Parts. And that the Pores of the Body are capable of receiving very subtle Effluvia, might be evinced by several Instances; but it may suffice to intimate, that I have so prepared a Mineral Substance, that it would have very sensible Effects on Substances contained in the Bladders of dead Animals, when it had no other way to get to those Substances than through the Pores of the Bladder, which are not near so perspirable as other Parts of the Body, not constituted to hold so subtle and penetrating a LIquor as Urine. Nor need it be a less Wonder, how these subterraneal Effluvia should have so sudden Effects on human Bodies, and in so little time, since we see in moist Wether, how suddenly Lute-strings are broke, and Ropes shortened by the Insinuation of moist Particles into their Pores. And tho' those Effluvia are not so plentifully dispersed in the Air, as to enter the Pores in such Swarms, yet the Mass of Humours may in time be sufficiently impregnated with those noxious Vapours to enable them to produce their Effects, when, sucked into the Capillary Vessels, they gradually deprave the Mass of Blood. And that Effluvia from without, may have considerable Effects on the Mass of Blood, appears from Appensa and Periapta, as also the Effects of Mercurial Plasters and Girdles; and the Effluvia of a Loadstone, which caused a Friend of mine to be troubled with Fits of the Colic, an Argument that Mineral Effluvia may cause particular Diseases. To which we may add, that Arsenical Appensa, extolled by some in the Plague, have produced the Effects of Poison, and in some a Faintness and Dispiritedness, according to the Testimony of several Physicians. And that Mineral Expirations may cause a determinate Distemper, we may learn from an Observation of mine, which was, That a Chemist rubbing very often Red Arsenic in a Mortar, and endeavouring to make an Excellent Medicine of it, first complained to me of a Difficulty of breathing, and sometimes of Pains and Tumours in his Testicles. And it will not be very much doubted, whether Mineral Effluvia penetrate the Pores of the Body or not, by those that shall know, that the Fumes of Sulphur are so penetrating, that at the Picinino of Teneriff, they blacken Silver in the Pockets of those that go up to it. I made a Preparation of Sulphur, which emitted Effluvia so powerful in the Cold, that they penetrated a Leathern Purse, and discoloured Silver contained in it. But besides the forementioned Effects of Vapours on the Picinino of Teneriff, I was told that one that ascended that Mountain, had the Colour of his Hair altered before he came down again; which argues the Power of Mineral Effluvia to penetrate the Pores of the Body. But lest it should be questioned by some, whether such Mineral Effluvia would not be consumed, and cease in less time than Endemical Diseases are continued in one Place; I shall imtimate that I think several subterraneal Bodies may have a power of propagating their Virtue to Matter contiguous to them, by some Seminal Principle, or something Analogous to a Ferment, or by bringing some more Crude Mineral Earth's gradually and successively to a greater Degree of Maturity and Perfection: For it hath been observed, that in Tract of time a Mineral might be obtained from an Earth which at another time it could not be obtained from; which Observation holds as to Nitre, which is one of the most Catholic Fossils', and most plentifully emits Effluvia. Besides, tho' Mineral Effluvia in the Region of the, Earth discoverable by us, should be consumed; I see not why supplies may not be brought from the Bowels of the Earth. Indeed, considering how closely the Matter of Minerals is crowded together, and how long Magnets severed from their Mines, emit Effluvia without a sensible Diminution, the Stock of Mineral Earth from whence they flow cannot be thought suddenly to be exhausted; for an Effluviating power is so durable, that one had a perfumed Watch, which, tho' constantly worn, preserved its Scent 16 years, and by the same Reason could perfume Marbles quite through, so that they retained their Scent a long time. But before I leave this second Proposition, it is requisite that I should take Notice, that noxious Effluvia may cause Distempers, not only by Respiration and penetrating the Pores of our Body, but by impregnating the Water made use of for preparing and Diluting our Aliment, without any sensible alteration in the Water to be discerned by us; So Water by an Infusion of Crocus Metallorum becomes Emetic; and indeed sometimes, those Effluvia are so numerous, that in the Borders of Lancashire, the Mud in a Ditch is so strongly impregnated with subterraneal Exhalations, that at the Surface of the Earth or Water they will take fire, and flame like a Candle. But besides that Distempers may be propagated by these subtle Effluvia impregnating Water, they may be also prejudicial, in as much as being mixed with the Nutriment of Plants, they may deprave their Juices, and consequently make them unfit to be eaten: And that Mineral Effluvia may in a great measure deprave and influence the substances of Plants in their growth, is confirmed by some, who have noted, that Oaks, growing in Ground which abounded with Vitriolate Mines, were much more heavy and solid than others; and these Effluvia are sometimes so numerous and crowded into the Pores of Plants, as not to be overcome and concocted by the Ferments of the Plants, but to keep their own Natures; for I have observed in a Vine near Paris several Marchasitical Particles throughout the Pores of the Root and Trunk. And I have been told that at Tockay in Hungary the very Kernels of the Grapes are as if it were Gild over with Leaf Gold. But, Besides the aforementioned Ways by which our Bodies may be affected with Noxious Effluviums, we may not a little suffer, by the depraved Humours which some Animals we Feed upon, are nourished by, and which vitiate their Bodies primarily, and secondarily ours. As from what hath been said it, appears, that Subterraneal Effluvia may cause Distempers, so it may not be amiss to take Notice that possibly in some measure Mineral Effluvia may prevent Distempers; for 'tis Observed, that several parts of Scotland are free from Agues, and that very hot and large Regions in the East-Indies are rarely troubled with the Plague; nor is it less remarkable that in Ireland the Air is impregnated with such sort of Emanations as prevent the Generation of any venomous Creatures; To which I shall add the following Instance from Beguinus in his own words, who says, Dignum admiratione est, quod quamvis in vicinia Hydriae Comitatus Gloricensis, ubi reperitur copiosè ☿ singulis fere annis Lues pestifera grassatur, illa tamen semper immunis ab hac manere soleat, idque viri providae aetatis se observasse, et a Majoribus suis accepisse mihi sancte confirmarunt; to which I shall add further that the Learned Michael Magerus, pronounces Mercury an Antidote against several Diseases; and particularly the Plague. PROPOSITION III. It is likely, Proposition 3. that divers Epidemical Diseases are in great Part produced by Subterraneal Effluvia. THo' several Epidemical Distempers are caused by manifest alterations in sensible Qualities of the Air; yet to show that some of them principally, and others partly depend on the Effects of Subterraneal Effluvia, I shall offer the following Considerations. And First, the Structure and disposition of the Parts of our Globe, which are not much below the Surface of it, and much more, the deeper Subterraneal Regions, are so plentifully stocked with Mineral substances; so, that it is not improbable but that Subterraneal Effluvia ascending thence into the Air, may cause excessive Heat or Cold, or some other manifest Qualities, and consequently in part occasion most Epidemical Diseases. For from what I have elsewhere shown, it not only appears, that these Effluvia, by acting on one another may excite sudden heats; but also that Minerals, of different Degrees of Maturity, acting on one another, may produce an Intense Cold. Besides, the changes of the Air on which Epidemical Diseases depend, are so considerable, and instantaneous, that they can scarce be attributed to the Influence of the Sun or Moon, which are too regular and constant in their Influence to cause such Anomalous effects, as we cannot but take Notice of in a few years' time; but are rather caused by an irruption of Subterraneal Steams, which are frequently both impetuous and irregular: And tho' some attribute them to the Influence of the Stars; yet the vanity of Judiciary Astrology having been so plainly detected by several Learned Men, I shall here only observe that it is much more unlikely that particular Towns should alone be Influenced by such, than by Effluviums from Bodies near the Surface of the Earth where those Places stand; and that which renders it much more probable is, that I have frequently known Diseases very Fatal to happen suddenly in some places, where the first Contagion hath been accompanied with a very troublesome Fog. That sudden and violent Heats may be produced by a Mixture of Subterraneal Bodies, not only appears from Oil of Vitrol poured upon Iron, Spirit of Nitre upon Butter of Antimony, Filings of Copper, Tin, or crude Antimony; But from Oil of Vitriol poured upon Powdered Marchasites which was accompanied with very strong Scented Fumes: To which I shall add, that even Sulphur hath to my knowledge had considerable effects on Marchasites: And I have been told by a Germane Chemist, that in Germany, Marchasites which were found there, would grow hot, if long immersed in pure Water. And if we consider upon how many Accidents the Course of Subterraneal Waters may be turned, it will be easily evident, upon that Account considerable Degrees of Heat may succeed; for if a convenient quantity of Filings of Steel be mixed with Powder of Sulphur, and that Mixture be moistened with Water, it presently grows very hot, and emits Fumes copiously, like Slak'd-Lime. And I have been informed by several, who frequent Mines, that Damps, which are made up of Subterraneal Effluviums, are not only very irregular in Reference to their Distance, but also their Duration; and have very ill effects on those that come within the reach of them; and if such pernicious Fumes are to be discovered so near the Surface of the Earth, well may they affect those that Inhabit on the Soil, near which such Effluvia rise: I say near which, because tho' they do not immediately rise in the very Towns they infect, and are carried thither by the Motion of the Air; yet in a large Tract of Land, they may be so dispersed as to have no considerable Effects. But it is not requisite always that those Effluvia, which cause Distempers, should be noxious at their first Rise from the Earth, since Mineral Fumes may acquire new Qualities by associating with particular Particles in the Air, and may by that means be disposed to act upon particular Parts of the Body, and to cause a determinate Disease: So tho' neither Spirit of Nitre nor Sal Armoniac alone can Dissolve Gold; yet Aq. Regia which is a Composition of both, will; but hath no such effect on Silver, Diamond's or Rubies. As for the Reason why Epidemic Distempers affect some and let others go free; it may not only be accounted for by the peculiar Dispositions of those Bodies, but also by considering, that the Effluvia which rise from the Earth, may be so imperfectly mixed with the Air, as to fall upon one Body, and not another; so I have observed several Leaves on a Tree blasted with a Wind which blew at that Corner of the Ground, yet others on the same piece of Ground were untouched; nay, the very Leaves of that were not all blasted on that side which the Wind blew, so that I suspected some Arsenical Vapours being mixed with the Air, cast upon them were like Hail shot from a Gun, and scattered in its Flight: And on a Cause not much unlike this may depend the Effects of some Winds which cause Blasts on the Faces of some People, yet let others go free, as I remember I was Riding once in the Wind, which, tho' it disaffected not me, yet my Man, who Rid after me, scaped it not. In favour of our Hypothesis already laid down, I shall add, that the short duration of some Distempers, as well as their Progressive Motion from one Town to another, are Arguments either that these Vapours rise all at once, and are dispersed, or the Subterraneal Commotion that causes them passes on from one Part of the Earth subjacent, to another. Nor is it less Consonant to our Hypothesis that the short duration of some Distempers may depend on a successive rise of Effluvia, since when those of one kind cease to be emitted, and another kind succeeds, the latter may check the former by precipitating them, or uniting into Quid Tertium less prejudicial to all Animal Bodies. So by an ascociation of new Particles with those Pestilential Effluvia which cause an Annual Plague in Grand Cairo, it suddenly stops, and those already infected, die not, if the Air be sufficiently impregnated before, as a late Writer of Voyages into Egypt testifies in these Words. The Drops or Dew purifies the Air; for as soon as it falls, the Plague ceases to be Mortal, none dies of it; The Air is wholesome, all Distempers cease; and if any person grows sick, he never dies, etc. I have been told that about the Tin Mines in Devonshire, not only the Grass and Fern, but the Trees will be suddenly blasted, by the powerful Effluvia which suddenly rise over a considerable compass of Ground. Having said thus much of Epidemical Distempers, it perhaps may be Expected that I should say something of the Plague and its Origin, which I must own myself at a loss in; for tho' I think it rather seemingly Pious, than really so, to ascribe such things to a Supernatural Power, which may be accounted for by Natural ones; yet I deny not but that some may arise from a Supernatural Origin. But what ever may be the first Origin of Plagues, I am inclined to think, that the Propagation of them depends on a Malignant Disposition in the Air, arising from some Subterraneal Effluvia; for these Reasons; First, because the Malevolent Aspects of the Planets seem too Remote and Indeterminate to act on a particular place. Besides, according to the vulgar Hypotheses, the Plague ought to rage's most where it very seldom happens: For Leo Africanus informs us, that in Numidia, tho' raging hot, it happens but once in an hundred Years; and Purchas in his Pilgrimage, Lib. 6. Cap. 13. tells us, it is not known at all in the Land of Negro, and seldom in Japan or New-England; and in the East-Indies, China, Tunquin, and Cochinchin●, it is never heard of: Whereas the Country of China contains more Inhabitants than all the Nations of Europe; and were the Plague a Punishment inflicted for the sins of Men, certainly in Countries so large and savage, they might expect it from Divine Justice as often as we. But perhaps it may be said, that these Histories as much Press our Hypothesis, as those others alleged by Physicians: But if we consider, that I confess it difficult to determine the Original cause, the other part of my Hypothesis is not at all shaken, since it could not be denied, but that noxious Effluvia would be able to propagate the Plague there, were there an Original cause to set those secondary causes on work: But for as much as from our Hypothesis it appears that the Original Cause of the Plague is not always so abstruse, but sometimes begun, as well as propagated by those noxious Effluvia, without the Concurrence of any other Cause, it may be requisite to take Notice; that in China and those Countries where the Plague, is unknown, we may presume such noxious Steams are not emitted; for tho' Sulphur is usually found in many Countries where Metalline Veins are frequent; yet I never heard that in those Mines an Ounce of Native Sulphur was ever found. Besides, tho' there may be Minerals in a Country which may emit noxious Vapours; yet the Mines from whence they come may by so deep in the Earth that they may not be able to infect the Atmosphere powerfully enough to cause a Pestilence, tho' promoted in making their Way by some violent Earthquake, when upon a fall of some weighty Mass of Earth in Subterraneal Caverns a trembling Motion is communicatted to the Earth about it, and propagated more or less proportionable to the first Cause; for which Reasons, noxious Effluvia being sometimes emitted which could not otherwise make their own way, probably the Plague happens in Africa once in 30 or 100 Years periodically. And a French Historian takes notice of a Disease in France, not much unlike the Colic, which, for a long time returned every 10th Year. And Platerus, Lib. 2. P. M. 303. Relates that the Plague at Brasil successively returned every 10 Years, for 70 Years together. But further, tho' in the East-Indies such Vapours should arise, which would of themselves be pernicious; yet others may rise, which tho' noxious likewise, may by combining with them, form a Third Substance innocent enough: So Corrosive Sublimate, when combined with Crude Mercury, becomes so useful and innocent a Medicine as Mercurius Dulcis. Besides what hath been said, another Reason why some Countries are free from the Plague, may be some peculiar disposition in the Air to resist the Effects of noxious Exhalations; as when the River Nile Increases and Overflows, the Plague in Egypt ceases: And the Soil in some Countries is of such a Temper as to impregnate the Air, so that it suffers not poisonous Creatures to live in it, A Second Reason why I think the Plague is propagated by Subterraneal Effluvia, is, because it happens sometimes when no Distemper is perceivable in the Air which seems able to produce such an Effect; yet when the Aspects of the Stars have been threatening enough, and the Air very intemperate, no Plague hath followed; as when Fernelius Writ his Observations De abditis rerum Causis, Lib. 2. Chap. 13. It was immoderately hot, but very Healthful; and the same further tells us, that the Plague hath sometimes begun in Winter, and gone off in Summer: And Johannes Morellus, that a Temperate and Healthful Spring, which succeeded a Winter, in which the Northwind Reigned, brought in the Plague, tho' at the same time, the Northwind continued serene and clear. And the Constitution of the Air before the Plague in 1665, was not much unlike it. Whence it is evident, that the Plague depends not on manifest Qualities of the Air, but is rather caused by Subterraneal Effluvia which float in it, and which are drawn in by Respiration; and that Poisonous Exhalations have rose from the Earth and infected the Air with a Pestilential Disposition, Monsieur de Meszeray in the Life of Philip de Valoris, and Diemerbroeck de Peste, Lib. 1. Chap. 8. testify. And tho' there is a manifest difference in Pestilential Distempers in several Countries, and at different times; yet it is easily accounted for by our Hypothesis, since the Minerals from whence those Vapours rise may be varied by new Combinations, and the Influence of Subterraneal Fires and Menstruums, as well as in the open Air, by which they may be enabled to produce Symptoms more violent than in ordinary Distempers; so that Hypocrates might well acknowledge in Distempers 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, something above the ordinary Course of Nature. The ill Effects of Mineral firmer As for the Natures of those Exhalations, tho' they are hard to be known, yet by the Effects and Symptoms of some Plagues, and of Yellow, Red, and White Orpiment, we may suspect them to flow from that Mineral Substance; but tho' I believe some Plagues may arise from such Causes, yet since the Earth abounds with several Minerals which we are not acquainted with, we cannot deny but by the combinations of such, there may result Substances which yield Effluviums hurtful enough to human Bodies; so by adding Common Salt to Orpiment, they prepare White Arsenic, which by the Mixture of Salt, of itself innocent, becomes more pernicious, causing violent Symptoms, which I have taken off by Oil of Sweet Almonds and something made of Lemons; And Sandarach, as well as Native Arsenic, seem to be little else than Red and White Orpiment, the Effects of which are taken Notice of by Sennertus. M. P. E. vid. Page 66. on a Painter, whose Face was swelled, together with Fainting Fits, upon opening a Box where Orpiment had been kept some time. And White Arsenic hath had very fatal Effects, when externally worn in Annulets, sometimes causing burning Fevers, Anxieties about the Heart, inflammations, exulcerations of the Breasts; Black Pustles, as if made with a Caustick, weakness and Fainting, and sometimes sudden Death, which Symptoms have been cured by the same Antidotes that the Plague is. And that Subterraneal Mineral Effluvia are able to effect very strange things, appears from what Kircherus observes, Scil. That in the Kingdom of Naples 1660, there were several Stains observed on Linen Clothes, much resembling Crosses, that poisonous Matter which was the Cause of them, being spread along the Threads, which crossed one another at right Angles. These Stains would wash out with Soap and Water; but their duration was very unequal, some of them contrinuing ten, and others fifteen days. Antidotes against the ill Effects of the Plague. And tho' it be impossible to discover the Natures of all noxious Effluvia; yet, undoubtedly a great many may, and Antidotes thought on to destroy their ill Effects. In the great Plague of London, when upon a subsidence of the Pestilential Humours, the Patients usually died, the following Plaster applied to the Tumours of several, prevented them from falling; and either burst or made them fit to open; and so saved the Lives of many. Emplastrum attractivum Pestilentiale nostrum. ℞. Gum. sagapen. Ammon. Galban. an ℥ iij. Terebinth. Lact. Cerae Virgins an. ℥ iiijss. Magnet. Arsenicalis subt. pulv. ℥ ij Rad. Aron. pulv. ℥ j Gummi depurentur cum Acet. Scyllit, & ad consistentiam Emplastri coquantur, & postea ponderentur, deinde cum rebus aliis F. Empl. S. A. Hoc Emplastro Carbunculus obducatur, quod paucis horis Venenum extrahit. Praeparatio Magnet. Arsenicalis anteà dicti. ℞ Arsen. Chrystallin. Sulphuris Vitri, Antimonii Crudi an. Haec tria in mortario ferreo pulverisentur. In Vase fortissimo Vitreo, ponantur ad ignem arenae, donec vitrum optime incalescat, & praedicta solvantur & liquentur instar Picis, quod observabitur quando filum quoddam immittitur in fundum, quod extractum postea instar Terebinthinae trahetur ubi satis coctum erit. Postea remove vitrum ab igne, & subtiliter pulverisa & ad usum serva. Another eminent Physician preserved himself from the Plague, by taking every Morning a little Sea Salt dissolved in Sea Water: And in another Plague, I knew two recovered with a Conserve made of Goat's Rue. Why the Plague sometimes unexpectedly ceases. But further, besides what hath been discoursed on; it is not less disagreeable with our Hypothesis, that sometimes the Plague unexpectedly ceases; since those subterraneal Effluvia, which continue the Infection, ceasing to be emitted from the Earth, those in the Air are soon spent and swept away with the Wind; which Effluvia may cease to be emitted; either because they meet with some other Effluvia in the Earth, which corrects them; or because they primarily risen from a Conflict and Agitation, depending on the mutual Action of two Bodies; which as Spirit of Salt poured on filings of Iron, or Aquafortis on Salt of Tartar, emit Fumes less plentifully, as the Ebullition declines. And that noxious Exhalations may be corrected, by a combination of others as pernicious, not only appears from what hath been before delivered; but may be illustrated by noting, that tho' Spirit of Salt-Peter will corrode Silver; yet, if Spirit of Salt be added to it, it soon loses that Quality. PROPOSITION IU. It is very probable, that most of the Diseases, that even Physicians call new Ones, are caused either chief or concurrently by Subterraneal Steams. New Diseases caused by subterraneal Steams. BY new Distempers, I would be understood to mean, not every one that varies a little in Symptoms from the same sort at another time; but such as at their appearance are, by their Symptoms altogether unknown: That these Distempers depend not on any intemperate and manifest Qualities of the Air; nor on the influence of those Heavenly Bodies, that move about us, seems evident; because the Influence of the latter are too indeterminate, and the alterations in the Temper of the Air, much more frequent than the Access of new Distempers. But from what hath been said under the Third Proposition, it appears, that the Globe we inhabit, abounds with various noxious Minerals, which are subject to various Confluxes, Conflicts and Dissipations; and which, by emitting Effluvia, may infect the Air, and cause new Diseases, which may continue accordingly, as the Cause is more or less durable; so Manna for these two or three Ages hath been found on certain Trees, which faculty of producing Manna, they still retain, yet had it not before. Experiments to show that Metals may be raised in the form of Vapours. To conclude this Chapter, and to render what we have taught concerning mineral Effluvia more probable, I shall add the following Experiments; from whence it will appear, that malleable Metals may be raised in the form of Vapours into the Air, and become part of Fumes, or perhaps of Invisible Vapours, or even of Flame itself. EXPERIMENT I. Dantisic Vitriol and Sea Salt Distilled. HAving powdered three Pound of Dantsic Vitriol, and two of Sea-salt, and distilled them with a strong naked Fire; we obtained a blue Spirit of Salt: Besides which there risen a Powder of a Cupreous and Martial Nature, which settled in the bottom of the Liquor. EXPERIMENT II. English Vitriol and Sea Salt. THE former Experiment being repeated with English, instead of Dantsic Vitriol, we obtained a Yellow Spirit, with a Yellow Powder, which seemed to be a Crocus Martis. EXPERIMENT III. Mercury Sublimate and Copper. WE cast thin Plates of Copper into a Retort upon a double weight of good Mercury Sublimate, and having luted on the Receiver, by a long continued Fire, we obtained some running Mercury, and some Sublimate, which had not fastened upon the Copper. In the Bottom of the Retort we found a weighty, brittle and resinous Substance, fusible and inflammable, almost like Sealing Wax; this being beaten and exposed for some time to the Air, turned to a kind of Verdigreese, which gave a green Tincture to Spirit of Salt. This being Distilled ad Siccitatem several times, till fully impregnated with the Spirit; it was mixed with Triply, and with a strong Fire afforded a colourless Liquor, like Water, which upon an Addition of Spirit of Hartshorn turned Blue. EXPERIMENT IU. Venetian Sublimate and Cornish Tin. VEnetian Sublimate Distilled from Cornish Tin, into a good large Receiver, yielded a Spirituous Liquor, which emits white Exhalations, upon an Access of free Air; but if the Orifice of the Vessel be but covered with a Piece of Paper, Air promotes the rising of Metalline Vipours. it presently ceases to emit those Exhalations; yet gins again, when that Paper, which lay but lightly upon it before, is taken off: Whence it appears, that the Air may promote the rising of metalline Vapours in the Atmosphere. And that Metalline Fumes will ascend in the form of Vapours, will appear from the following Experiment, viz. Having satiated Aqua fortis with Copper, and steeped some brown Paper in it to soak up some of the Menstruum, when the superfluous Moisture was partly evaporated, we laid some of it upon the Hearth, near a Wood Fire, upon which, the Paper being Scorched, emitted Fumes like Smoak, which rising up in the Air, as soon as they came to the Flame, they imparted to it a Colour, partly Blew, and partly Green; as it was variously mixed with the Flame and Smoke of the Wood CHAP. XX. Suspicions about some hidden Qualities of the Air. Latent Qualities in the Air. BEsides the four first Qualities of the Air, viz. Heat, Cold, Moisture and Dryness, and those which Philosophers and Chemists have discovered, as Gravity, Springiness, etc. I am apt to suspect, that there are other latent Qualities in it, due to the substantial Ingredients, which it is made up of: For the Air we live in, is not a simple Body, but a confused Aggregate of Effluviums; which, being jumbled together, constitute a great Mass of Heterogeneous Matter, endued with different Qualities. For from what is elsewhere delivered, it appears, that there are various Effluvia, besides those that afforded ordinary Meteors, which arise from Bodies in subterraneal Parts; several of which have no Names, or at lest none assigned them, and have several Powers and Qualities which we know not of. Besides, the Sun and Planets may have Influences here below, distinct from their Heat and Light, which may mix with the Atmosphere we live in: And for as much as those celestial Globes that move about us, may be endued with substances, that we here know nothing of, the Effluviums which come from them, may affect us in a different manner from any Bodies, we here have in our Atmosphere. And though the greatest Part of those Effluviums, Qualities in the Air which arise from the Union and Conjunction of other Bodies with it. which are active in our Atmosphere, arise from subterraneal Parts, and from Celestial Bodies; yet doubtless there are a great many that result from the mutual Action of the different Parts of it acting on those Bodies that are exposed to it; for tho', notwithstanding any manifest Qualities we can discern in it, the Air seems to be unfit for a Menstruum; yet I doubt not, but it may have considerable Effects on Bodies disposed to be acted on by it; for not to urge, that sometimes the Quantity of a Menstruum compensates its want of strength; we know, that there are several Liquors, which, though insipid, and make no sensible Impressions, on the Organs of Taste, yet by their various Attritions and frequent Motions against Bodies, become fit for Solvents: So the Air, having its Parts always acting on Copper exposed to it, in tract of time, produces that Efflorescence coloured like Verdigrease; a factitious Body usually produced from the same Substance corroded by Vinegar or the Juice of the Husks of Grapes. Besides, we see, that Mercury, which hath no sensible Taste, hath a faculty of Dissolving Gold and Silver, and all Strong Menstruums, which dissolve Bodies with the utmost Vigour, are soon glutted, and can dissolve no more; so that, tho' the Air be a weak one, yet it hath this lasting Advantage, that when a small Quantity of it is glutted, it bears so great a Proportion to the Body it acts on, that a fresh Part of it is still to supply the Deficiency and Place of that which can act no longer. The Air abounds with saline and sulphureous Parts. Besides, the Air abounds with so many saline and sulphureous Parts, that by rubbing upon Bodies that lie in their way, by frequent occursions, they cause considerable Effects, so we see, according to the Proverb, Gutta cavat Lapidem, non vi, sed, saepe cadendo. Moreover, tho' the Parts of Air are very minute, yet, we know, that the Bodies which are exposed to their Action, are only acted on by them upon their outward Superficies, which may consist of as many Parts, and as minute as those of the Air, which, by successively hitting against them, carry them along with them: So Sugar or Sal Gem. being immersed in Water, have their Parts dissolved and carried up into the Liquor, by the successive attritions and occursions of so insipid a Menstruum, and whose Parts are in so gentle a Motion. The Sunbeams sufficient to raise some Bodies. And I am apt to believe, that some Bodies have may such a disposition, to be worked upon by the Sunbeams, as to be raised by them in such a form, as not to be distinguished from the Body they are raised in. But whether they may or not, certainly it is consonant to Experience, that the Atmosphere is filled, in several Places, with Effluviums of different kinds, and of uncommon or unobserved Natures; which Conjecture may be favoured, by observing, how subject Camphire is to waste; and that, when the Superficies of some solid Bodies have been taken off they emitted Steams copiously, by which in a Minute of an hour, they suffered a manifest decrement of weight. Arguments to prove latent Qualities in the Air. But to reassume the Discourse we have made this Digression from, I shall urge some Arguments à posteriori, which favour what I proposed concerning these latent Qualities in the Air. And first, I shall urge the appearing growth of some Salts, in Bodies, which usually afforded them not at all, or not in such plenty; Vitriolate Efflorescences having been observed to be, after sometime, on the glistering parts of Marchasites, which were kept in a dry Room: And it hath been observed, that a heavy ponderous Mineral exposed to the Air for some time, became so brittle, that it would crimble away, and plentifully abounded with Copperas; and some of the same being kept in a close and dry Place, was in some time covered over with an Efflorescence, which being mixed with an Infusion of Galls, manifested itself to be a Vitriol; whose growth is the more strange in the Air, because it is not a mere Acid Salt; but abounds with combustible and sulphureous Parts, which I have often separated from common Vitriol without the addition of any combustible Matter; and sometimes without any addition at all. And it was not a little strange that our blackish Minerals, yielded vitriol Efflorescences so soon, since I kept shining Marchasites, from whence they usually prepare Vitriol, without being changed near so much, as those I have mentioned; and it is usual, sometimes, to let them lie exposed to the Air two Years, before they yield their vitriolate Parts. Alum Over regains its Salt when exposed to the Air. To these Observations we may add, that Alum Over, being robbed of its Salt, recovers it again by being exposed to the Air; and Lime in old Walls hath in time regained a Nitrous Spirit, which I have learned by dissolving it in common Water, and evaporating the filtrated Solution. Nay, And so does Vitriol. calcined Vitriol exposed to the Air, in a competent time regains fresh Parts of a vitriolate Salt. Suspicions about the Productions of Vitriol. But though I propose these Observations as favourable to the Suspicions laid down; yet I am apt to suspect, that the Air concurs to the Production of them, rather as an Ingredient, than as an Agent; or that the Production of them depends on some seminal Principle, by which, when they are once ripened, the Moisture of the Air helps them to disclose themselves in the Form of saline Concretes; as in Tartarous Matter saline Parts are generated, which cause that acid Taste in Tartar, of Rhenish Wine especially: Besides, it may be suspected, that the Salt found in Marchasites, etc. may be made of saline Particles swimming in the Air, and attracted by congenerous Particles, that remain in those Bodies, that are, as it were, the Wombs of such Minerals; or that these Aerial Salts, assisted by the Moisture of the Air, open the Textures of these Wombs, and by extricating the latent saline Parts, and adjoining with them, compose those emergent Bodies; but though I suspect, that the Air is not wholly concerned in producing such Bodies, yet I believe it is in a great measure concerned, as I have already intimated. The necessity of Air to continue flame, an Argument of a latent Principle. But to proceed to other Instances of these Aerial latent Qualities, I think that the necessity of the Air's Presence to preserve and continue Flame, is a sufficient Argument of some latent Spirit or Quality, whether vital Substance or nitrous Spirit diffused through the Air, on which likewise the Life of Animals depends, and without which, they, as well as Flame, presently, are extinguished and die. To these I shall add, that Animal Substances enclosed in Vacuo, yield not Infects, as when exposed to the open Air; And it is related by a Noble Man of this Country, that an Oak being dug out of a Rock of Salt, was so hard, that Iron Tools could scarce work upon it; yet in three or four Days, being exposed to the Air, it was rotten. And it hath been observed by several, that the Air hath such an Influence on Diaphoretick Antimony, that if it be long exposed to it, it becomes Emetic. From which Observations, and what I have before laid down concerning Quicklime, the Air seems to be a Substance capable of being assimilated by every Body, The Air seems to consist of all sorts of seminal Principles. or that it consists of all sorts of seminal Corpuscles; so that any Body may find a Substance there, analogous to it, and fit to make up a part of the same Body. But without any further notice of this odd Surmise, I shall subjoin the following Phaenomena to favour my Suspicion. The first is, That tho' the Juice of the Fruit of the Tree Junipa (which the Indians use to black their Faces, to make them more formidable to their Enemies) gives such a Tincture, that it cannot be washed out with Soap; yet the Air abounds with Particles of such a Nature, that it disappears in ten Days time; tho' I suspect that, it in a great measure depends on the continual Excretion of Sweat, through the Pores of the Skin. Damascus S●… 〈…〉 And I am informed, that Instruments made of Damascus Steel, tho' when first made, they excel not, or scarce equal those of commo● 〈◊〉 yet when kept in the Air two 〈…〉 they answer Expectation and a●… 〈…〉 proved. And I have observed, that 〈…〉 ●…e Body, which would not be dissolved in a strong Menstruum, nor lose its Colour by Fusion, would presently be turned black, if exposed to the Air. Remarkable Changes of Colours. It is observed in Blood concreted, that the black internal Parts being exposed to the Contact of the Air, become florid; and I have prepared a factitious Concrete, which if kept to the Fire, or secluded from the Air, would be of a red Colour; yet in a quarter of an hour, being exposed to the Air, it would turn almost black. To which I shall add, that an inquisitive Person prepared a Medicine of a vegetable and Animal Substance, which at that time of the Year would be coagulated in a Viol like Oil of Aniseeds; but if unstopped and exposed to the Air, it would presently dissolve again, and recoagulate when stopped up again; The Consideration of which Experiments may tell us, that the Air by being communicated to the Blood by Respiration, may have Effects not inconsiderable upon it, in carrying off its fuliginous Recrements, To what hath hitherto been delivered in favour of our Suspicion, it may be added, That there are Anonymous Substances and Qualities in the Air; To countenance which, I shall take notice of those various and odd Diseases, incident both to Men and Beasts, which prove Mortal to a particular Species of Animals, and in particular Places, which depend on some unknown subterraneal Vapours: To which I shall subjoin, that Fernelius mentions a Plague, which affected no Animals but Cats; Dionysius Halicarnassus, takes notice of one that only affected Maids; whereas, that which raged in the time of Gentilis, seized none but Lusty Men: And Bolerus gives us an Account of another, which only affected the younger sort of People. Cardan speaks of a Plague at Brasil, which only affected the Swissers, and neither the Italians, French or Germans; and Johannes Vtenhovius gives an Account of a cruel Plague at Copenhagen, which only raged amongst the Danes. As for the Cause of these Diseases, though I think they are chief to be ascribed to subterraneal Effluviums; yet I deny not, but that the Particular Constitutions of Men are concerned in them; nor do I think the Distempers already mentioned, alone depend on such Steams as rise from the Earth, but the Sudor Anglicus in the 15th Century, the Scurvy and the Morbus Hungaricus, the Lues Moraviae, Novus Morbus Luneburgensis, and some others in the last Century. Considerations drawn from what hath been said. And now, if from what hath been said, our Suspicions concerning Subterraneal and Steams, may seem not ill grounded; they may lead us to consider the following Particulars. 1. Whether those Effects, which are sometimes thought to depend on the immediate Wrath of God, and the Intercourse of Angels, may not arise from these Steams, whose Qualities are probably heteroclite, and unknown; since we see that there are several Steams dispersed through the Atmosphere, which cause it to raise Mercury in a Baroscope, which could be no otherwise discovered, but by the Effects they have on the Air, made evident by that Instrument. And this Consideration hath sometimes made me suspect, that even the Sunbeams may cause a manifest Gravity in the Atmosphere besides that which they do by virtue of their Heat; and it may be worth Enquiry, whether some Spots in the Sun, upon their Dissolution, may not be dispersed through, and cause some considerable Effects in our Atmosphere, at least in its Gravity. 2. It will not seem improbable, that some Bodies have peculiar Dispositions to be associated with those Exotic Principles, which arise from subterraneal Parts, or are transmitted from the Planets. Upon which Dispositions, or the contrary, what we call Sympathy and Antipathy depend. By Virtue of such Dispositions, a Burning-Glass refracts the Sunbeams, and the Sunbeams impart a Lucidness to the Bolonian Stone. And that the Steams of subterraneal Bodies will act on some Bodies, and not on others we have given sufficient Proof. 3. The third thing which may be suggested by what we have delivered; is, whether there may not be Receptacles or Attractives of Syderial and other Exotic Effluviums, that wander up and down the Air, such as are Magnets; by which I mean, not such a Body that can attract foreign Effluvia; but such a one as can detain them, when by virtue of their various Motions they happen to come near such a Magnet. Just as Oil of Tartar per Deliquium draws to it, aqueous Vapours, and embodies with them, when they chance in their Passage through the Air to come near it. But a greater resemblance of the Magnet may be allowed to some Bodies, than what is here mentioned; for such a Magnet may not only by a Juxta-Position or Contact detain the Effluviums, that would glide along it; but also arrest those subtle Parts of Matter by a kind of precipitating Quality; and so it may fetch in some Effluvia, which would otherwise pass by it: On which occasion, I remember, that in some Cases, I have been able to give some Bodies Electrical Qualities, without exciting them by rubbing, etc. CHAP. XXI. Some Additional Experiments relating to Suspicions about the Hidden Qualities of the Air. EXPERIMENT I. Experiments relating to occult Qualities of the Air. HAving poured Water upon the Calx of Dantzick Vitriol, part of it, soon after it was sufficiently impregnated, with the Vitriol remaining in the Calx, was filtered and gently abstracted, and yielded several Grains of a Salt of Vitriol, not much different from that which had been calcined. Another Portion of Water was left in the Air six Weeks, upon the calcined Vitriol in a wide mouthed Glass, and then being abstracted as the former, it yielded a Salt much like Salt-Petre, and different from the former. And Colcothar which had lain several Months in the Air free from Rain, being turned into a Lixivium, yielded a Salt much whiter than Vitriol, and of a different Figure. From whence it appears, that the Air hath considerable Force in varying Salts obtainable from calcined Vitriol. EXPERIMENT II. Dulcified Colcothar of Venereal Vitriol being exposed to the Air in January and February, increased in Weight 4 ¼ Grains. EXPERIMENT III. THE 12th of March, Eight Ounces of Outlandish Vitriol calcined to a Redness, being put into a broad and flat Metalline Vessel; and into another Vessel smaller than the other, we put 2 Ounces of Colcothar, so that the Superficies of the latter, was larger, in respect of its Quantity than the Superficies of the other. June 25. We weighed these Powders, and found that the 8 Ounces had gained a Drachm and 16 Grains, and the 2 Ounces had gained as much within a Grain. Then the Powders being put into the same Vessels, August the 4th, the smaller Quantity weighed 26 Grains more than it did in June. Whence it appears, that different Circumstances cause notable Disparities in the Increase of Weight. EXPERIMENT IU. TWO Ounces of small Lumps of Marchasites, which were partly shining, and partly darkish, and seemed well disposed to yield Vitriol, were kept in a pure Air, and gained 12 Grains in Weight in seven Weeks. EXPERIMENT V. SPIRIT of Salt being put upon Filings of Copper, and kept in a moderate Heat, when it had acquired a thick and muddy Colour, we decanted it into a clean Glass, with a wide Mouth, and left it a competent time exposed to the Air, till it had acquired a fair Green; yet nothing was precipitated to the Bottom to make it clear. EXPERIMENT VI. I Once Observed, that the Fumes of a sharp Liquor acted more powerfully on a certain Metal, held in the Air, than the Menstruum, from whence those Fumes risen, would do itself. And it is observed in some Mines in Hungary, that the Fumes render those Ladders soon unserviceable, which were nearest the Top of the Grove, where there is a more free access of Air. EXPERIMENT VII. A Soft Chemical Substance, which would smoak in the open Air, being conveyed into our Pneumatick Engine in a Viol, when the Air was exhausted, ceased to smoke; and by continuing there some time, would not smoak again, when it was re-exposed to the Air, till the fresh Air had blown upon it some time. This Preparation, being kept in the Vessel it was prepared in six Weeks, would cease to smoke, when the Vessel was but covered with a piece of Paper; and another remarkable thing was, that when it was contained some time in a Receiver, close Luted, it would soon so glut the Air with its Steams, as not to be able to smoak longer. CHAP. XXII. Of the Celestial and Aerial Magnets. IT would be of great Use in discovering the Nature of the Air, and its Correspondency with Subterraneal and Celestial Regions, could we, Of Celestial Magnets, ctc. by Experiment, make any progress in preparing such artificial Magnets, as would imbibe the Exotic Parts of the Air. Nor will it be lost Labour to expose several Mineral and other Substances to the Air, and to inquire, what it is that gives them the additional Weight, they receive by it; and with what Qualities that Substance is endued; for if such Experiments could be tried with good Magnets at several times, and in several places, we might by them learn, what Effluviums the Air, then, and in those places, abounded with; nor might it be of small Importance in discovering a correspondency betwixt the Terrestrial and some Etherial Globes of the World. Amongst other things which make me hope that Equiries of this Nature may not be altogether unsuccessful; I shall only intimate, that Notable Operation the Air hath upon Vitriol, diversified by circumstances, after Fire could work no further on it: For Zwelser speaking of a Chemical Preparation of Vitrol, Viz. Colcothar, says, that the Salt it yields, when long kept, is imbibed into it, from the Air. For, says he, when it hath been exposed to the Air, Sal praebet, quandoque candidum, quandoque purpureum, aspectu pulcherrimum, quod aliquando in Copia acquisivi, & penes me asservo, quandoque etiam Nitrosum. And an ingenious Person told me, that he likewise had obtained several sorts of Salts from Colcothar; and at the last, when it had been kept a long time, a pretty quantity of true running Mercury. Besides what hath been already said, concerning Colcothar, I shall propose two or three Inquiries, to any Virtuoso, that would assist in these Trials. And first, it will be convenient to note, the Nature of the Soil; the Temperature of the Air; the Month of the Year; the Winds; the weight of the Atmosphere; and, if any, the Spots of the Sun; the Moon's Age, and her place in the Zodiac, as well as the principal Aspects of the Stars and Planets; since we cannot deny, tho' not positively assert, that these Bodies are concerned in the production of those Salts which Colcothar yields: This, nevertheless we know, that, tho' those Bodies which move about us, should have no considerable effect on what is done in our Atmosphere; yet it, at different times and Places, abounds with various subterraneal Steams, and several Phaenomena appear in it, which are irregular, and tho' some are regular enough, yet are they as to their Causes unknown, as those Thermae Piperinae in Germany; which begin and cease to flow at certain times: And Johannes de Laet tells us, that in the Mexican Province, Xilolepec, there is a Fountain, which successively flows and ceases to flow for four Years together; and in the time of its flowing, it's observed, that it flows much more plentifully in dry, than Rainy Wether. Secondly; I would recommend the following Observations, viz. What kind of Vitriol the Colcothar is made of, Martial, Hungarian or Roman Vitriol; what degree of Calcination is made use of, and how far the Calcined Matter is freed from its Salt by Water: For I have observed, a Saltless Colcother exposed to the Air several Months, without the least increase of Weight, which probably might depend on some Peculiarity of the Air, where the Experiment was tried, since in other Places, the success hath been the contrary. But Thirdly; Besides several sorts of Vitriols, it may not be amiss to try these Experiments with several Preparations of them; for I once made a Solution of Copper with Sublimate and Spirit of Salt; which, exposed to the Air, was green, tho' before, it was not of that Colour, but of a muddy Red; and some which, appeared to be a dirty Liquor, as long as it was kept in the Vessel it was made in, free from the Air, appeared to be of the Colour of an Emerald, when exposed to it. And what was remarkable in these Experiments, is, that accordingly as the Qualities of the Matter and Circumstances differed, the green Colour appeared sooner or less speedily. But to conclude: Tho' the success of Experiments of this kind be very doubtful; yet since the Attainments are so desirable, it may encourage the curious, not to pretermit the Advantage, which may succeed such Endeavours: For as Mariners at Sea, who at a distance upon the Horizon, some times see something obscure which, whether it be a Cloud, a Mountain, or an Island, they cannot distinguish, yet it hath proved worth their while to approach it, and not lose the probability of a Discovery; so, who knows, but by making an advance in less promising Experiments, we may discover something which may richly reward our Pains. CHAP. XXIII. Experiments and Notes about the Mechanical Production of Magnetical Qualities. Magnetical Qualities Mechanically pronuced. THo' the Operation of a Loadstone is justly reckoned amongst occult Qualities, and thought to flow from the substantial Form of the Magnet; yet I see no Reason, why it may not be easily mechanically produced; since a Piece of Steel, fitly shaped, and well excited like a Loadstone, points to determinate Poles, viz. North and South, draws other Pieces of Steel to it, and Communicates to them in a faint degree the same Attractive and Directive Virtues, which are not slight and transient Impressions, but durable and lasting; where it is evident, that, tho' the Steel is endued with magnetical Virtues, yet it hath not the Form of a Loadstone; but only, the Metal by the Action of a Loadstone acquires such a disposition in its Parts, as inables it to perform Magnetical Operations; which Power it loses again, by being heated red hot, and cooled in the Air, yet the Form of the Steel is still the same: And from what I have in another place laid down, it appears, that a Loadstone itself may lose its faculty of attracting Iron, and yet retain all it's other Qualities; Nay, tho' it is a peculiar Quality of a Loadstone, to point North and South; yet without destroying its substantial Form by Fire, the Poles may very easily and speedily be changed, if a small Fragment of a Loadstone hath its Poles successively applied to a very vigorous Magnet. But to make it further appear, that Magnetical Qualities may be Mechanically produced, or altered; I shall add, that I have observed, that whilst the Parts of well tempered Steel have been excited to Motion by Rubbing, they would draw to them Filings of Steel, or thin Fragments of Steel or Iron; but when the Adventitious Warmth acquired by that attrition ceases; they presently lose their attractive Power: And I have elsewhere observed, that the lower end of a perpendicular Bar of Iron, hath been so far altered by the Effluvia of the terraqueous Globe, as to be turned into a kind of Magnet, whose lower end becomes the North Pole of it, and the other the South; to which Observation we may add, that if the Bar of Iron stand but a while in an erect Posture, the Magnetical Qualities of it will be so transient, that if the upper End, which attracted the North end of a Needle, be inverted and held downward, it will drive it away; and on the contrary, if it remain a long time in that Posture, the change wrought upon it is so great, that a Piece of a Bar of Iron, which was upon the Top of a Church, called Arimini, in Italy, by the Rustyness of it, and the Magnetical Virtues it had acquired, seemed to be turned into a Loadstone. And further, it may be observed, that if a Piece of Iron, have its Pores opened and loosened, it imbibes the Magnetical Effluvia of the Earth so fast, as to acquire Magnetical Virtues much sooner. And here it may not be useless to observe, what different Effects, Fire hath upon two different Bodies; for by keeping a Loadstone red hot, it loses its attractive Power, tho' afterwards, it be cooled in a perpendicular Posture; whereas, Iron, by being heated and cooled in a perpendicular Posture, acquires a manifest Virticity; so that the internal Texture and Constitution of the Loadstone, seemed to be destroyed and weakened by Ignition: From whence likewise it appears, that Magnetical Qualities may be altered by, and depend on Mechanical Principles. And, To these Observations, I shall add further, that having brought a Piece of Ochre to a convenient Shape, and after I had heated it red hot, suffered it to cool in a convenient Posture, it was able to exercise Magnetical Operations on a poised Needle. And indeed, a convenient Posture, so much contributes to the preservation of Magnetical Qualities, that leaving a very vigorous Loadstone, for sometime, in an inconvenient Posture, it lost considerably of its Magnetical Virtues. And this corruption of Magnetical Qualities is further evident in an excited Needle, which, as it is variously touched with this or that end of a Loadstone, points with this or that end Northward or towards the South. To make it yet more probable, that Magnetical Virtues may be Mechanically produced and destroyed, I shall subjoin, that by an Experiment tried by the Ingenious Dr Power, it appears, that a Bar of Iron, ignited, and suffered to cool North and South, and hammered at both Ends, will lose its Magnetical Virtues, by two or three smart Blows, upon the middle of the Bar, with a Hammer. CHAP. XXIV. Chymico-Magnetical Experiments and Observations. Magnetical Experiments and Observations. THE Loadstone being a Body, whose Nature is so little known, and whose Qualities are so admirable, I shall, in order to the better Understanding of it, lay down some Experiments, made upon several, brought from different Countries, and of different Sizes, Shapes and Colours. But before I proceed to them, it is requisite to advertise, That although the Title of this Chapter be Chymico-Magnetical, yet all the Experiments contained in it are not Chemical, several others being mixed with them. Also it is requisite to note, that Iron and Steel being usually reckoned amongst Magnetical Bodies, I have also added a few Experiments made upon them. EXPERIMENT I. SEveral Stones being heated in the Fire, had, by the Action of it, their Texture visibly altered; some being brittle, others flying asunder of their own Accord, whilst others continued whole; in which it was observable, when broke, that some were not unlike Iron Over; whereas others were shattered into flakes or plates of various Colours: But some, which were English, reserved their Solidity and Colour. EXPERIMENT II. SEveral small Loadstones being burnt, we could not perceive the least of that sulphureous blue Flame, which Porta, Lib. 7. Cap. 7. of his Nat. Magic, takes notice of. EXPERIMENT III. & iv IT is worth observing, that several Loadstones, being struck with Steel, afforded Sparks of fire much bigger than those that are usually struck from Flint. Whereas two cubial pieces of Loadstone being struck together, afforded Sparks, but not so large as the former. EXPERIMENT V. IF an oblong Loadstone be cooled in a perpendicular Posture, the lower End becomes its Northern Pole; yet if that End instead of being exposed to the Effluvia of the Earth be cooled, whilst resting on the Northern Pole of a strong Loadstone, it will be the Southern Pole, and will attract the North End of a Needle. EXPERIMENT VI. IF a Loadstone, which hath lost its attractive Virtue, be heated red hot, and cooled in a perpendicular Posture upon the North Pole of a vigorous Loadstone, and continue there for some time, the attractive Virtue is renewed. EXPERIMENT VII. A Loadstone that hath lost its attractive virtue by Ignition, will not acquire so durable an attractive Virtue, by being applied cold, as hot, to a Loadstone. N. B. Tho' several Loadstones lose their attractive Virtue by Ignition, yet the Observation does not hold in all; since English one's, not only retain a Directive, but an Attractive Virtue after it. EXPERIMENT VIII. HAving heated two Loadstones red hot, and placed them upon a Plate of Silver, we found, that as they grew colder, it had a more sensible Operation on them. EXPERIMENT IX. WE observed, that one of the two Magnets just now mentioned, not only retained something of its Magnetical Qualities when twice ignited, but being thrust into Filings of Steel, carried a considerable Quantity of them up with it; which shows, how firmly the Qualities of some Magnets are lodged in it. EXPERIMENT X. BUT we observed, that the Magnet which would thus carry Filings of Steel along with it, being heated again, and suddenly immersed in Water; when cool, would not carry Filings of Steel along with it, as before, nor would not move a well-poised Needle, except held near to the Point of it. EXPERIMENT XI. AN oblong Loadstone of a black Colour, which weighed about three Drachms, by being kept some time in a Charcoal Fire, lost much of its Colour, and about ⅚ of a Grain in Weight. And to discover the Affinity betwixt a Loadstone and Iron Over, I took a Lump of it, which was almost like white Stone; and observed, that it did not only manifestly move a Needle, but when ignited, underwent a sensible Change in Colour, and would attract the North End of a Needle. EXPERIMENT XII. TO prove that some Bodies, not usually classed amongst Magnetical ones, have nevertheless Magnetical Qualities, I shall subjoin; That a Brick being divided into two oblong pieces, and heated in the Fire, acquired a Verticity by cooling North and South, it's Southward End being in some measure able to draw the North Point of a Mariner's Needle, which the other End of the Brick would drive away. EXPERIMENT XIII. HAving without the help of Iron Instruments powdered a black Loadstone, and poured Spirit of Salt upon the fine Powder, it caused such an Ebullition, as usually succeeds the Effusion of that Liquor upon Filings of Iron, and likewise raised fetid Fumes: And being kept for about two Nights in Digestion, extracted a strong Tincture, being almost red, and not green, like that of Mars; yet would, like that of Iron, turn a Tincture of Galls black, which in several Positions would appear Blue. And to this I shall add, that a Solution of Loadstones being made in Aqua Regia, the Tincture appeared to be of a golden Colour. EXPERIMENT XIV. HAving powdered an ignited Loadstone, and digested Spirit of Salt upon it, it extracted a Tincture, which was much like that of troubled Gold, and would turn an Infusion of Galls black: This Tincture being evaporated, would not shoot into Crystals, but upon an Affusion of Salt of Tartar, yielded a Precipitate much resembling a Solution of Vitriol, whereas another Part of it upon an Addition of Spirit of fermented Urine, afforded a yellowish red Precipitate. EXPERIMENT XV. HAving wet a red Mineral, (which I suspected to be Iron Over,) with Linseed Oil; and preserved the Powder in a red hot Crucible for about two hours, it was turned black; and when cool, had acquired a Magnetical Virtue, which another Portion of it did, tho' it was not as the other, wet with that Oil. CHAP. XXV. Experiments and Notes about the Mechaninal Origin and Production of Electricity. Of the mechanical Production of Electricity. THO' Electricity be a Quality, generally reckoned amongst the Number of those that are termed occult ones; yet there is no need to ascribe it to the power of a Substantial Form, since it may be mechanically produced by material Effluviums, issuing from, and returning to the Electrical Body, assisted in its Operation by the External Air. There are several Modern Hypotheses which endeavour to account for Electricity; as the Learned Cabeus', who supposes that, the Steams of the electrical Body discussing and expelling the ambient Air, that, when driven off, is violently opposed by the Atmospherical Air, and being driven back upon the Body said to be attracted, forces it up to the electrical Body. Another Hypothesis, proposed by the Ingenious Sir Kenelm Digby, and embraced by Dr. Brown and several others; is, that the Electrick Body being rubbed, emits unctuous Steams, which being cooled by the External Air, shrink back, and carry along with them, those light Bodies which lie in their way. Of this Opinion is Gassendus, who supposes these unctuous Steams to cross each other, and by getting into the Pores of Straws and other attracted Bodies, take faster hold of them, and when they shrink back, draw those Bodies along with them. Cartesius rejecting these Hypotheses, supplants another, which I cannot in few Words lay down; but all the Reason he rejects them being, because he supposes Glass incapable of emitting Effluvia; it will be sufficient to remove that difficulty, to Observe, that if two Pieces of Glass be rubbed together, they emit odorous, and sometimes very Stinking Effluvia. But without taking any further Notice of what Moderns have laid down about Electricity, since they allow it to be performed by Virtue of subtle Emanations from the Attracting Body; It may suffice, that I proceed to mention some Phenomena, that make us probably believe it done by Virtue of Mechanical Affections, either of the Attracting Body, or both. And First, it is Observed, that most, if not all Electrical Bodies, attract not till warmed; by which heat they are enabled to send forth Eufflvia. Secondly, Amber attracts most vigorously when warmed by rubbing and Chafing; by which Action, the Motion of the Effluvia, as well as of its internal Parts are more agreeably modified, than by the Action of Fire; but if the Parts of the Amber be first put into Motion by the Fire, and then Modified by Chafing, it sooner becomes Electrical. Thirdly, Tersion, as well as Chafing, promotes Electricity, by removing those Bodies, which might choke the Pores of the Amber, and obstruct the Efflux of Emanations, by sticking to the surface of it. Fourthly, Electrical act not like those more subtle Magnetical Steams, since the Operation of Electrical Effluvia, are obstructed by the Interposition of a piece of the finest Linen or Sarsnet. Fifthly, Electrical Effluvia act less vigorously in Thick and Cloudy Wether, especially, if the South Wind blows; and on the contrary they act likewise more faintly in the Night than in the Day. Sixthly, Most Electrical Bodies are made of Matter, capable of emitting Odoriferous Steams by Heat and Attrition. Seventhly, For which Reason, Bodies continue their Electrical virtues sometimes after the attrition; the Commotion in the Parts of the Concrete, caused by that attrition, not immediately ceasing. Eighthly, To make it probable that Electrical Effluvia may insinuate themselves into the Pores of other Bodies, I shall add, that I found them subtle enough to attract Spirit of Wine, and also the Smoke of an extinguished Wax-taper at a considerable distance. Ninthly, The Electrical Virtue depends not on any Sympathy betwixt the Body Attracting and the Substance Attracted; since Amber indifferently draws to it all Bodies, which are not too gross, except Fire, by the violent Motion of whose parts, the Electrical Emanations are dissipated, and the Fire determined another way. Tenthly, A vigorous and well excited piece of Amber will attract not only the Powder, but less minute Fragments of Amber; and the following Experiment may give us Reason to believe, that the Electrical Effluvia of the Attracting Body, not only fasten upon the Body to be drawn, but that the Cohereing Particles of the Effluvia make up viscous Strings, which intervening betwixt those two Bodies, when their agitation ceases, shrink inward, and are contracted; as a highly stretched Lutestring, when permitted to shorten its Dimensions: The Experiment was this, viz. We suspended a piece of Amber by a Silken-thread, by the help of a piece of Wax, and then rubbing the Edge of it with a Pin-cushen covered with Course black Stuff, when it was well excited, and brought to settle, we observed, that if the Cushion was held near the excited Edges, the Effluvia would fasten upon it, so that when the Cushion was removed, the Amber would follow it several times for the space of ten or elven Minutes. Electricity Mechanically produced and destroyed. But to proceed to what I promised in the Title of these Papers, I shall add some Experiments to show, that Electricity may be Mechanically produced or destroyed. EXPERIMENT I. A Fourth Part of Good Turpentine being evaporated, the remaining substance hardened into an Electrical transparent Gum. EXPERIMENT II. THE dry Mass which remained after a Distillation of Petroleum and strong Spirit of Nitre, being a brittle substance like Jet, resembled it in its Electrical Quality. EXPERIMENT III. THE Transparent Glass made of Antimony burnt to Ashes, had a considerable Degree of Electricity. Which is the more worthy our Notice, because, that as a Vitrum Antimonii, which is accounted purer than ordinary, may be made of the Regulus of the same Mineral, (in whose preparation a great deal of Sulphur is separated and left amongst the Scoriae) so Glass of Antimony made without Addition, may in part be reduced to a Regulus (a substance not looked upon to be Electrical:) Nor is some peculiar and fixed part of Antimony alone capable of Vitrification, since of the other Part, which usually flies away, an Antimonial Glass may be made, without an Addition of other Ingredients. EXPERIMENT IU. I Once prepared a Glass of Lead per se, which had a Languid Electricity, and which would afford a Malleable Lead again, which is not in the least Electrical. EXPERIMENT V. AMber being Distilled per se, the Caput Mortuum being quite burnt was black, and brittle, and not in the least like Amber; yet tho' it's substantial Form was destroyed, it was more vigorously Electrical than Amber itself; And as it appeared from the Instance of Glass of Antimony above, that the remaining substance may retain an Electricity, tho' the Form of the Body be destroyed, and part of it dissipated; so from common Glass, we may Learn, that a compound substance may be Electrical, tho' the separate Ingredients were not. EXPERIMENT VI. Electricity may be produced by unheeded and fortuitous Causes. TO make it appear that Electricity may be caused by unheeded and fortuitous Causes, without depending on the substantial, or even Essential Form of the Attrahent, I shall subjoin, that Locks of some Hair being brought to a certain degree of Dryness, by Curling or otherwise, have been oserved to be attracted by the Flesh of some Persons, as Hair is wont to be by excited Amber; which they were more subject to do in Frosty Wether. To try whether the Air was much concerned in Electricity, I suspended a piece of Amber (which, when excited, would stir a poised Needle ¼ of an Hour) in a small Receiver, and when the Air was exhausted, the Amber being let down near a Straw or Feather, attracted it in Vacuo. EXPERIMENT VII. TO show that the Attraction of light Bodies, depends on very small circumstances, I made use of a Downy Feather taken off the Body of a Fowl, to which when it had been attracted by an excited piece of Amber, I applied the end of my Finger to it, upon which it stuck and left the Amber. The same success I had, when the Experiment at distinct times was tried with the Tip of a Silver Instrument, and Iron Key, and, a piece of black Polished Marble. We had the like success, when the Experiment was tried at several distant times afterwards. But one thing remarkable was, that if the Amber had lost its attractive virtue, before my Finger or the other Bodies were applied, the Feather was not disposed to stir, till the Amber was again excited. To conclude these Notes, I shall advertise, that the event of Electrical Experiments is very uncertain, and varied by slight Circumstances, some of which are altogether overlooked, which in some Measure appears from the above recited Notes. And therefore I shall add, that sometimes it is very hard to know whether a Body be Electrical or not; for, tho' Kircher denies Crystal to have an attractive power; yet I have observed the contrary. And tho', the industrious Gilbert denies Electricity to Cornelians and Emeralds, yet all that I have tried, had some Degree of it, except one Cornelian. And indeed Electricity is constantly inherent in Diamonds, so that it may be one good way to try whether they be Genuine, since most of them are considerably more attractive than common Glass. But to conclude, I shall add further, that rough Diamonds are Observed, to have a faculty of attracting much more eminently than Polished one's; for which no other Reason can be conceived, but that the Diamond in Polishing, being considerably, Heated by the Mill, several and a great part of its Electrical Effluvia are spent and fly away. CHAP. XXVI. The General History of the Air begun. TITLE I. What we understand by Air. BY Air, I mean, that thin, Diaphanous, fluid Body in which we Breath, which encompasses the Terraqueous Globe, and is capable of Rarefaction and Condensation; so different from Aether or Vacuum, that it refracts the Rays of the Moon as well as other Remoter. Luminaries. TITLE II. Of the constant and permanent Ingredients of the Air. Of the Naure of the Air. BY Air, I would not be thought to mean, such Artificial and Temporary Air as usually flows out of an Aeolipile, when one that is furnished with Water is exposed to a sufficient Heat, and then condenses into Water again; but common Air, which is Permanent, and continues in that Form; Which I conceive, is made up of three kinds of Particles. The first are Effluvia, from several substances belonging to the Terraqueous Globe: The Second are the Magnetical Steams of the Earth, and Emanations: The Third are these Elastic and Springy Parts of the Air which are Permanently so. As for the Structure of these Elastic Parts, they may be conceived different as men's contrivances devise to answer Particular Phaenomena: One may think them like the Spring of a Watch; others like a Fleece of compressed Wool, endeavouring always to expand themselves; others, like Curled pieces of Wire, of different Lengths and Thickness, and diversified by being more or less Curled: All of which may be capable of being compressed and expanded again, by virtue of their Native Structure, Heat, Girations and other Motions. I have likewise compared 'em to thin shave of Wood, which are of different Sizes; and this comparison may in some Measure Illustrate their Generation, there being no Art requisite to the production of such, nor curious Instruments; and yet their Curls are very different and seemingly Casual; as also their springness depends on their convenient shape. And the Generation of Air may be further illustrated, by observing, that these springy Chips may be made of the Parts of Beams and Blocks, not at all Elastical before. Which favours an Experiment I made, wherein, by the Action of a Menstuum upon a Mineral Body, a quantity of Fire was Generated, permanently Elastic. But not to multiply Conjectures about the Structure of the Parts of the Air, I shall add, that, tho' their Elasticity seems to depend on their Structure; yet it may be increased, by quickening their Motion by the Action of Fire; Besides, there may be several Elastic Parts in Air, whose Elasticity may rather depend on their Motion, than Figure, they being, thereby enabled to strike against Bodies about them, and to keep them off. And not improbably in these warmer Climates, the parts of Temporary and Artificial Air may be put into such Motion, as may for the time keep it fluid; those parts of Matter being disposed to be kept in Motion. TITLE III Of the Aether in the Atmosphere. TITLE IV. Of the spongy Particles of the Air, and the the Spring of the Air. Aerem va: lide comprimere aur dilatare. FOllibus lusoriis aerem pyulico ingerentes majorem subinde atque majorem difficultatem percipiunt; quo enim magis Aer conclusus naturali raritate recedere cogitur; etiam majore nisu resistit, neque solum magis densari renuit, sed & se latiùs explicare molitur. Hinc didicimus & pneumatico fontes construere, qui Spiritu interno urgente aquam in altum evibrant, & plumbeas Glandes fistulis ejaculari, non pulvere nitrato ignem concipiente, sed aere per vim densato ad antiquas dimensiones recuperandas erumpente. Quoniam verò ingesta jam in conceptaculum non exigua aeris copia difficilius comprimitur nouâ aeris accessione; quam ut manus valeat trusillum recta impellere, idcircò trusilli hastulam deformatam in helicem; & suae Matrici insertam, adhibere oper pretium erit, dum enim manubio agitante contorquetur Cochlea, sensim deprimitur Embolus, aeremque ingerit. Ne autem mora longiore opus sit perpetua versatione Manubrii, ita Cochleae Matrix externam vasis faciem contingat, ut illi adnecti, atque ab eo disjungi valeat: initio enim, quando adhuc levis est aeris modice compressi resistentia, lamella illa suo foramine interius claviculatim striato cohaerens hastulae emboli, si à vase disjuncta fuerit unà cum hastula movebitur: deinde verò, quando jam trusillis aegrè impellitur, lamilla illa cum Vase connectatur, & non nisi versato Manubrio adduci atque reduci Embolus poterit, id quod satis lentè perficietur: Rem claritatis Gratia in fonte Pneumatico explicemus. Sit vas A. B. ex materia Metallica, in cujus superiore parte labrum, ex quo perforamen A. immittatur in vas aqua, ita tamen, ut non impleatur; aqua enim in vas modice inclinatum descendens, aerem expellet per Tubulum C. D. ubi satis Aquae immissum fuerit, occludatur foramen A. diligentissime Cochleola congrùente & convoluto Epistomio E. Tubus D. C. sit Aeri impervius ad vasis latus statuatur modiolus cum embolo congruente H. I. & emboli hastula sit connexa cum mobili vasi ansa, H. O. Porro hastula H. K. perforata sit, & continuo ductu usque ad emboli K. F. fundum pateat Aeri ingredienti via H. S. sed foramini S. adjecta sit Valvula, quae Aeri regressum obstruat. Similiter modioli fundo in I. Valvula exterius apposita aperiatur ingesto Aeri transitum praebens; sed Aeri intra vas compresso cum nusquam exitus pateat, Valvula ipsa modioli foramen I occludit. Hastulae verò H. K. exterior facies sit in helicem striata, & lamellae M. N. tanquam Matrici congruat, quae in M & N. Cochleolis adnecti queat exteriùs vasi, quasi esset ansae fulcrum. Vbi immissum fuerit quantum satis est aquae, Cochleolis M & N. revolutis disjungatur Matrix à vase: tum attractâ ansâ H. O. una cum Lamella M. N. attrahitur embotus K. S. & per apertum ductum H. S. ingreditur Aer, modiolum implens. Impulso deinde Embolo, Valvula ad S. clauditur, & Aer ex modiolo, per patentem Valvulam I. ingreditur in Vas; ex quo nequit exire, neque aquam propellere, clauso scilicet Epistomio & foramine A. quapropter comprimitur, & densatur; ideoque attracto denuo Embolo K. S. inclusus vasi Aer se latius explicare connitens Valvulam L. F. valide applicat foramini modioli, sibique exitum obstruit. Toties adducitur atque reducitur Embolus, & Aer ingeritur, quoad magna premendi difficultas percipiatur; ubi eò ventum fuerit, tunc Lamella M. N. iterum vasi adnectatur suis Cochleosis; nec jam Embolus recta adduci queat; sed areptum in O. manubrium versatur, & Embolus intra modiolum circumactus sensim attollitur, qui deinde revoluto in contrarium Manubrio deprimitur, & multa vi Aer in vase comprimitur. Laxato demum Epistomio E. compressus in vase Aer, aquam exprimit per Tubum C. D. primum quidem vehementius, subinde remissius, prout Aeris vis elastica sensim conquescit. Hoc idem quod de Aere intra Vas comprimendo ad aquam evibrandum comminisci placuit, servatâ analogiâ, dicendum est de Aere, tum conatu manûs rectâ trusillum impellentis, tum ope Cochleae similiter conformatae, intra conceptaculum comprimendo, ut ex fistula deinde multa vi emittatur plumbea Glans, ubi reseratus Aeri exitus illum subito dilatari permiserit. Quin & Pneumatica hujusmodi tormenta citra conceptaculum Aeris compressi construere non inutile accidat, si, quemadmodum nostrates pueri surculos sambuceos fungosa medulla exhauriunt, & utraque Tubuli extremitate papyraceis Globulis obstructa, alterum Globulum congruo Cylindro propellunt, atque inclusum Aerem densant, quoad Aeris vim elasticam, & impellentis manûs Conatum, non ferens extremus alter Globulus edito scloppo expellatur; ita ferream fistulam longiorem paraveris, cujus alteri extremitati immittatur plumbea Glans, obducta papyro, aut simili Materia, ut exquisitè Tubi osculum implens, demum universam Aeris vim excipiat, alteram extremitatem aliquot Spiris ambiat cava Cochlea, quam impleat Cylindrus ferreus in congruentem Cochleam deformatus; si enim hujusmodi Cylindrus, vis brevior fuerit, quam fistula, & apto Manubrio convolutus, in fistulam sensim immittatur, totum Aerem, quo fistula replebatur, ad exiguas spatii angustias adiget, ex quibus magna vi demum, qua data porta, erumpens, ejacul abitur plumbeum Globulum Casati Mechanicorum, Lib. 8. Cap. 5. p. 792. 793. etc. TITTLE V Of the Magnetical Particles in the Air. TITLE VI Of the Destruction, Generation, Absorpsion and Extrication of the Air. Concerning the Production of the Air. AIr being a body not only concerned in agreat many Phenomena of Nature, but likewise so necessary to the Preservation of Animals; Is thought it of no small use to thy whether it might be Artificially prepared and obtained from Bodies which seemed not at all to abound with Air; for could it be done, it would not only be considerable in helping to explain several Phaenomena of Nature, but to preserve Divers much longer under Water. To try therefore whether it might be effected, and whether that which seemed to be Air, were truly so; I made use of the following Experiments, taking a durable Springiness or Elasticity as the Criterion, by which I should judge, whether the Air generated were Genuine or not. EXPERIMENT I. Jan. 17. Air generated by a mixture of Oil of Vitriol and Filings of Steel. FIlings of Steel, and a conveniently shaped Glass, which contained Oil of Vitriol, and was sealed at both Ends, but with a Hole opened near one of them, were coveighed into a long and large Tube, so much Water being put in with them as was sufficient to dilute the Oil. This being done, and the External Tube and the Water exhausted, till the Mercury in the Gage was so far raised in the open Leg, that little remained in the sealed Leg; we closed up the External Tube exactly, and observed, that when the Oil was caused to run out of the internal Tube, by acting upon the Metal it caused several Bubbles, and a sensible Heat; when this Conflict had continued some time, so much Air was generated, as depressed the Mercury in the open Leg down to the Bottom; and raised it so much in the other, that the Air above it was more compressed, than when the Atmosphere had free Liberty to press against it. The Spring of this newly produced Air was so strong and durable, as to keep the Mercury at ●he same height 3 or 4 Days; and some Days after, a Boy having heedlessly removed the Tube from its usual Station, the Mercury in the Gage ascended an Inch and a half, at which Height it continued till the 25th of January. EXPERIMENT II. March. 8. Flower moistened with Water. A Glass Viol., which was large enough to hold a Pint, was filled with Flower of Wheat drenched with Water; and the Orifice being closed with a Cork and strong Cement, after the Glass had been placed 13 Days in a warm Place, it was burst by the Violent expansion of the included Matter, tho' the Night before, part of the Glass below seemed empty. The Taste of the included Matter seemed to me only a little sowrish; but to another manifestly acid. EXPERIMENT III. March 9 Raisins included in Vacuo with Water. BRuised Raisins with a little Water being put into a Bolt-head; when it was exhausted, I placed it in a warm Place. In four Days no Air was generated; but some time after the Bolt-head was burst in pieces, and the Raisins thrown about. EXPERIMENT IU. Feb. 22. A Glass, which would hold about 3 Pound of Water, having a sufficient Quantity of Raisins put into the Water, a Bladder was tied to the Neck of it, which had all the Air squeezed out, and, in two Days time, it was so filled with Air, that we could not tie it up, without losing some of the Water. EXPERIMENT V. April 28. SPirit of Salt, and Filings of Steel, being put into a wide mouthed Glass, we covered it with a Receiver, fitted with an Eel-Skin and a Wire, to the latter of which, a thin Glass Vessel was tied, hermetically sealed at the Bottom, and furnished with a sufficient Quantity of Filings of Copper. This being done, and the Receiver exhausted, we thrust the Glass which contained the Filings, against the Bottom of the Viol, and broke it off; whereupon the Filings falling into the Menstruum, a considerable number of Bubbles were generated. The Viol being kept ¼ of an Hour longer in Vacuo, the Liquor acquired not the least Greenness. EXPERIMENT VI. Air shut up in Oil of Turpentine and Spring Water. A Bubble of Air about the Size of a Pea, being left at the Top of a round Viol with a long narrow Neck, the Cavity of it being filled with fine Oil of Turpentine, and then inverted into a Viol filled with the same Liquor; Another Viol which had a Bubble in the Top, was filled with Alcohol of Wine, and inverted it into the the same Liquor. On the sixth Day the Bubble in the Oil disappeared, and on the seventh, that in the Spirit of Wine vanished. EXPERIMENT VII. May 23. Frog 's Spawn: A Receiver, which had been three Years exhausted, was opened; and a black opacous Liquor, which we judged to be Frog's Spawn, which was contained in a Viol, being taken out, was of a stinking Smell, but not mouldy. It had yielded some Air. EXPERIMENT VIII. IT is observed, that when Miners meet with running Waters under Ground, they are by those, supplied with Air enough for Respiration; tho' it is observed, that standing Waters do not afford Air. Experiments about the Production of Air, and the Examining thereof proposed. Sect. I. To produce Air by Fermentation in Receivers exactly closed; and in sealed Glasses. Sect. I. To separate Air from Liquors, by boiling; or by the Engin. Sect. I. To obtain Air by Corrosion, especially with Spirit of Vinegar. Sect. I. To separate Air by Sulphureous and Animal Menstruums. Sect. I. To produce Air in Vacuo by Burning-Glasses and hot Irons. Sect. I. To obtain Air from Gunpowder, and other nitrous Substances. Sect. II. The Air produced may be examined, by trying whether it will Preserve or Revive. 1. Animals. 2. Flame. 3. Fire. 4. The Light of Rotten Wood, Fish. Sect. II. To examine its Spring, and the Duration of it, as also it's Weight, and whether it will help to raise the smoke of Liquors. TITLE VII. Of the Accidental or less constant Ingredients of the Air. TITLE VIII. Of Aqueous Particles in the Air, and of its Moisture and Dryness. Of the Air 's Moisture and Dryness. THO' Dryness be a Quality which only depends on this, viz. That the Pores intercepted betwixt the stable Parts of a Body, are not filled with any visible Liquor; yet it hath a considerable Interest in the Changes of Bodies upon different Scores. First, In as much as the Body dried is deprived of Liquid Parts, upon the Effects of which, several of its Operations depend. Secondly, Upon the Recess of those Parts evaporated, the Texture of the Body may be so far changed, as to acquire a disposition to act otherwise, and to be acted on in a different manner to what it was before. EXPERIMENT I. TO evince the Efficacy of the Air's Moisture, we suspended a Quarter of a hundred Weight by an Iron Ring at the End of a Rope, which was about 3 Foot and a half long, and 3/10 of an Inch in Diameter; and when the Weight had stretched the Rope for 2 or 3 Days, we placed a Board under it, so that it might just rest upon it, and then causing the Rope to be wet, in about half an hour it shortened so much, that the Weight would swing this way, and that, like a Pendulum without touching the Board; yet the same Day the Rope was stretched again, so that it touched the Board. About Morocco, which is an Inland Town, tho' the Soil be dry, and the Heat violent in the Day; yet I am told by one who was there, that the Nocturnal Air was so damp, as to be able to make his unfit to be worn, till Aired; yet, tho' the Air was very piercing, neither the Knife in his Pocket, nor the Sword in his Scabbard were subject to rust, tho' the same Metal exposed to the open Air, was. Air too moist cannot be wholesome. The Air about Oakly and Brill in Buckinghamshire, tho' a high Country, is so moist in October, that the Staircases and Pictures will stand all over Dew, which gathering in drops, runs down in Streams; and it is obsered, that the North and North-East side of the Houses are so moist, that except the Rooms be aired often, the Furniture will rot. Having made use of a Hydroscope which was made of a Box, to whose Bottom a piece of Gut-string was fastened, and the other End of it to an Index, which lay upon the Top of the Box, the Circumference of the Box was divided into Degrees, or Partitions; By which we could perceive, that when Moist Vapours insinuated themselves into the Pores of the Lutestring, it would be wreathed and twisted up, and the Index would be moved that way, which the twisting of the Rope inclined it, and when the Wether was drier, it would return back the other way. EXPERIMENT II. ONE of these Hygroscopes being conveyed into a small Receiver, when the Air was exhausted, the Index did not sensibly alter its Place in a long time; till the External Air was let in again. From which Experiment, and some others tried with a Thermoscope, it appears, that the Aether, or that subtle Matter which succeeds in the Place of the exhausted Air, is neither hot, cold, moist, nor dry. TITLE IX. Of Clouds, Mists and Fogs. Of Clouds, Mists and Fogs. AN excellent Astronomer told me, that of all the white Clouds, whose Height he had measured in fair Wether, he found none to exceed ¾ Quart. of a Mile; and very few above ½ a Mile. A Mist at Sea driving towards the Shoar, without any sensible Wind, causes the Sea to swell more than a brisk Wind. It hath likewise been observed, that Mists in some places rising about 30 Foot high, have fallen down in a Dew again. TITLE X: Of Terrestrial Steams in the Air. Of Terrestrial Effluvia. PIllars of Fumes have been divers times observed to rise from Ground which had several Veins of different Metal in it, some ill scented, some well scented, and others inodorous; and I have observed, that the Charcoal made in Cornwall affords a manifest Arsenical and Sulphureous Smell beyond other Charcoal. Jcournal des S avary, III. 1685. Tell est par exemple ce nuage horrible d'une fumée epaisse qui s'eleva de la mer de Cretee au Commencement de l'Eestede l'an, 721. et qui s'etant repandu dans l'air le fit parôistre tout en feu. La mer n'en fut pas mesme exempt, car les grosses Masses de pierres enflammées qu'on en vit sortier, et qui se joignirent al' Isle qu'on Nomme Hiera, échauferent si fort les eaux qu'elles en bruloient les manes. TITLE XI. Of Salts in the Air. Of the Salts in the Air. THO' the Peripatetics teach, that the Air is an Element, and consequently a pure simple Body, whose Qualities are moist and dry; yet from what we have already delivered, it appears, that it is an Aggregate of various kind of Effluvia jumbled and mixed together; I mean, the Air distinct from that Purer Substance Aether, which I suppose diffused through the Interstellar Part of the Universe. Amongst the Effluvia which rove up and down the Air; I account Saline one's the Chief, which is not unlikely, since the Terraqueous Globe, which continually emits Effluvia, abounds with great Quantities of Marine, Aluminous and Vitriolate Salts, which impregnate the Air; besides several Exhalations raised by the Sunbeams, from the Surface of the Earth and Water; not to mention several other Saline Vapours which are dispersed in the Atmosphere, and arise from Vulcanos, as well as common Fires. And as it is not improbable, but that the Air plentifully abounds with Saline Effluvia; so very likely, besides Nitrous, there are other kinds raised up and roving about in it; as Common Salt, and Vitriolate Salts; and that which seems to prove, that the Air in some places abounds with vitriolate Salts, is, that it hath been observed, that Hinges have been corroded and rotten, and other things prejudiced upon a Vitriolate Soil, whereas in Houses, which stood on a Chalky Soil, no such Effects were observed: Besides, on the Vitriolate Ground, we took Notice of Saline and White Efflorescences upon the Surface of the Soil, when beaten upon by the Sunbeams. Besides which kinds of Salt, I am induced to believe, that the Air abounds with Volatile ones; For besides, that an Acquaintance of Mine obtained a Spirit and Salt of Similar Qualities with Spirit of Hartshorn from Earth dug up some Yards deep; we may observe in favour of what I propose, that the very Soot which rises from fires near great Towns, a great part of which is dispersed in the Air, abounds with a Saline Spirit, which may be obtained from it by Distillation; as likewise, a great quantity of Volatile Matter may be raised in the form of Vapours from Animal substances putrified and corrupted. But besides these more simple Salts, there may be several others compounded in the Air, which may result from several Coalitions of simple Salts; and several Compound Salts may, not unlikely, arise from Subterraneal Parts: In favour of which I shall add, that in America the Effluvia of a Vulcano, not only offended, the Faces of some that approached too near, but caused a manifest alteration in the Colour of their Hair. And it hath been observed that several Sulphureous Exhalations have been gathered about the Crannies of Mount Vesuvius, which issuing out of small Crannies stick to the Edges like Flower of Brimstone: To which I shall add, that I had a Stone brought me from another Vulcano, whose Pores were full of a White Salt compounded of a fixed one, and another Volatile much like Sal-Armon. The Salts we have hitherto taken Notice of, are such as may be referred to a determinate Species: But I am apt to believe, that there are others which are such as are not known, nor have they any Names given them; this appears from what we have elsewhere taught of Subterraneal Fumes; and may be further illustrated, by intimating, that I have observed Old Glass-windows sometimes corroded, as if Wormeaten; which probably proceeded from some corrosive Particles carried thither by the Wind. As for the Nature of these several Salts, that at different times, and in various Places, impregnate the Air, amongst the different Methods that might be taken to investigate them, I shall mention the following. Several ways to discover the Nature of the Salts in the Air. First, We may expose such Bodies to the Air, as we think will most likely be worked upon, by the Salt we judge Predominant in that place; as Lime, where we think Nitre abounds; as also we may hang up Silks of such Colours as Nitre is most apt to fade, or discolour. In places where we think Vitriol abounds we may expose Preparations of Sulphur, which it usually turns Black: In other Places we may spread White Linen , and observe what Salts they imbibe along with the Rising Vapours and Falling Dew. A Second way to discover the Nature of the Salts in the Air may be, by exposing some Body, which several Salts have different Effects on. EXPERIMENT I. CLean Copper Plates being placed over Glasses, under which, Spirit of Salt and Spirit of Nitre diluted with Water, were set. I Oserved, that they were discoloured alike by the ascending Fumes; it being common for these Spirits to draw a green Tincture from Copper as Spirit of Soot and Urine do a Blue one. I have observed a piece of Copper brought from a Mine overcast in several Parts with a Verdigrease, which effect I judged to depend on the Efficacy of some Effluvia in the Air. And possibly with other Bodies, discovering different discolourations, we be enabled to learn what kind of Steams those Effects are produced by. And it hath been observed, not only at Amsterdam, but elsewhere, that Plate, in a little time, in those Airs, would acquire a Rusty Colour, or one partaking of Yellow and Black. A Third way, which may be taken to discover the different Nature of Effluvia, may be by exposing Preparations of Mineral Bodies, whose Colours are apt to be changed by the Air. EXPERIMENT II. IF a Solution of Silver in Aq. Fortis be precipitated with Spirit of Sea Salt, the Powder will be at the First White; but after a while being exposed to the Air, the Surface of the Liquor will acquire a dark Colour, which may perhaps vary as the Air is differently impregnated. EXPERIMENT III. AN equal Weight of Filings of Copper and Powdered Sal Armoniac, being mixed and put into a Covered Crucible, and kept over a moderate Fire till the Sal Armon. had done Smoking, as much of the remaing Mass as could be parted was taken out, and looked of a Dark Colour; but being grossly beaten and exposed to the Air, looked like Verdigrease, a substance whose Colour commonly varies, according to the Nature of the Salts concerned in the production of the Pigment. But a Parcel of the same Mass being grossly beaten, and Hermetically Sealed up from the Air, and left in a South Window, was not discoloured when that exposed to the Air, had acquired a Virdigrease Colour. EXPERIMENT. iv SPirit of Soot of Wood dissolved Copper into a lovely Azure; but the substance growing dry in the Air, changed its Ceruleous for a Cyanious Colour, such as may be seen in good Turquoises. Which Change depended not on the Saline-Sulphureous Salt. Which I rather believe, because I had the same success when I made use of an Urinous Spirit drawn from an Animal substance. Most of the Inland Parts of our Country abound not with Corrosive Vapours, the Bars of Iron being not so subject to be corroded and Rust; So that I believe this Salt may proceed from Sea Vapours, or a dissolution of some Corroding Salt, upon the burning of a Sea, or Mineral Coals. Mox ollam ex igni removent; Agricola de re Metal. Lib. 12. postea ex refrigerata eximunt halinitrum purissimum: quod candidi marmoris speciem gerit; aetque tunc etiam id quod terrenum est, in fundo residet. At terra, ex qua dilutum fuit factum, & Rami quernei vel consimilis Arboris alternis sub dio ponantur, & aqua quâ combibit halinitrum conspergantur: quo modo quinque vel sex annis rursus apta fit ad conficiendum dilutum. Halinitrum quodammodo purum, quod dum terra tot annos quievit interea, ortum fuit, & quod lapidei parietes in Cellis Vrinariis & locis opacis exudant, cum primo diluto permistum decoquatur. Si verò locus aliquis talium venarum, copiam suppeditaverit, ipsae statim non conjiciantur in cast ella; sed primò convehantur in areas, atque cumulentur: quanto enim diutius aeri & pluviis expositae fuerint tanto meliores fiunt. Name in ejusmodi cumulis, aliquot post Mensibus, quam Venae in are as fuerint conjectae, nascuntur fibrae longe venis bonitate praestantes: deinde vehantur in sex, plurave Castilia longa & lat a ad novem pedes, ad quinque alta. Si verò dum dilutum recoquitur, seperata non fuerint, mox ex minoribus Vasis infundatur in Majora, eaque concludantur; in quibus item atramentum sutorium seperatum ab alumine concrescit utrumque incisum & in Hypocausto siccatum divendatur dilutum, quod in vasis & cupis non concrevit in cortinam, refusum recoquatur: sed verra, quae in fundo cujusque cortinae resedit, ablata in castella unà cum verra; denuo aqua & urina dilutaur. At terra quae in Castellis diluta, postquam effluxit, superfuit egesta & coacervata quotidie, rursus magis ac magis fit aluminosa, non aliter atque terra, ex qua halinitrum fuit confectum, suo succo plenior fit: quare denuo in Castilia conjicitur, & aquae effusae ea percolantur. And I have not only been informed, that the Dews in the most Southern parts are more than ordinary Corrosive; but that in Basil they are so Esurient, that the Portugals are forced to keep their great Guns cased up; in which Country the same Person told me the very Money was corroded by the sharpness of the Air; and he likewise observed, that the Dew left a White Salt upon the Grass, which looked like a Hoar Frost. And I am likewise informed by a Native of the Place, that in a Town called Fahlure in Sweedland, which stands upon the bottom of a Hill, which hath a Copper Mine in it, The Exhalations are so powerful as to Corrode Iron and Brass, and even Money itself, tho' locked up in Chests of Wood an Inch thick. TITLE XII. Of Sulphur and Inflammable Particles in the Air; and of Lightning, and its Effect. Of Sulphur and Inflammable Matter, etc. A Neapolitan Lord told me, that Riding upon Sulphureous Ground, the Horse's Feet would raise a Dust, which would be ready to take Fire; and when purposely, he had caused several pieces of that Earth to be cut like Turffs, and to be laid in a heap, in the Night, the Steams which plentifully risen from them, would sometimes take Flame; And the same Lord told me, that near Mount Vesuvius, He observed the Flame so violent, than when Measured by a Quardrant, it appeared to be near two Miles high above the Top of the Mountain, and that great Flakes of Fire were thrown up into the Air as big as the Room we talked in. Voila tout ce qu' on peut dire cette Isle, qui semple un enfer car on voit la mer du port, Voyage de Levant. page 203. & de la coste toute noire & brûlee d'un petit escuel, qui paroist depuis environ soixante ans, & d'ou on vit sortir en ce temps la une grande flamme, qui is a laisse une ouverture si profonde, que si on y jette une pierre, on ne l'entend point tomber. Mais ce qui est arrive depuis en ce port, n'est pas moins estonnant; je le rapperteray icy comme je l'ay appris de diverses personnes en plusieurs endroîts. Ily a environ 18 ans que durant la nuit d'un certain Diamanche, commenca dans le port de Santorini un tres grand bruit lequel s' entendit jusques à Chio, qui en est eloign deplus de deux cent mills, mais de telle sorte qu' on crut a Chio que c' estoî l'armèe venitienne qui combatroit contre celle des Turcs, ce qui fit que des le matin chacum monta aux lieux les plus elevez pour en estre Spectateur, & me souviens que le Reverend Pere Bernard superieur des Capucins de Chio, homme Venerable, & tres digne de foy, me conta qu'il y avoit este trompè comme les autres, car il crut aussî bien qu' eux eux entendre pleusieurs coups de canon; cependent ills ne virent rien, & en effect ce fut un feu qui seprit dans la terre du fond du port de Santorini, & y fit un tel effect, que depuis le matin jusqu' au soir il sortit du fond de la mer quantite de pierres de ponce, qui montient en haut avec tant de roideur & tant de bruit, qu' on eust dit que ce fusset autant de caups de canon, & cela infecta tellement l'air, que dans la dite Islle de Santorini, il maurut quantite de personnes, & plusieurs de la Mesine Isle en perdirent la veve, qu' ils recovurerent pourtans quelque jours apres. Cette infection s' estendît ausi loin que le bruit quî l'avoit precede, car non seulement dans cette Isle, mais mesme a Chio, & a Smyrne, tout l'argent devint rouge, soit qu' il fut dans les Coffres', ou dans les poches; & nos Religieux demeurans en ces lieux la me dirent que tous leurs calices en estoient devenus rogues. Au bout de quelques jours cette Infection se dissipa, & l'Argent reprit sa premiere couleur, les pierres de ponce qui sortirent de la couvrirent tellement la mer del'Archipel, que durant quelque temps, quand il Regnoit de certains Vents, il y avoit des ports, qui en estoient bouchez, en façon qu' il n'en pouvoit sortir aucune barque, pour petite qu' elle fut, que ceux qui estoient dedans ne se fissent le Chemin au travers de ces pierres de ponce avec quelques pieux; & on en voit encor a present par toute la mer Mediterranée mais en petite Quantite, cela s' estant disperse ca et la. Seneque raconte en une de ses Epistres que Santonini est bastte sur des mines de souphre, & ce sont elles qui fournissent asseurement la matiere pour allumer en cet endroit, & n'y trouva point de fond. Il y a pourtant une petite Isle appellée Firesiá, á la pointe de laquelle▪ on peut donner fonds, & point en aucun autre endroit. It is usually observed, that there is a strong smell of Sulphur near where a Thunderbolt falls. When I was near the Lake of Geneva called Lacus Lemanus, there was a terrible Storm of Thunder, and the next day so strong a smell of Sulphur, that a Soldier who stood near the Place where a Thunderbolt fell into the Water, could scarce bear the smell of the Sulphur. July 24. 81. A Ship being at Sea about 100 Leagues off Cape Cod in 48 Latitude about 3 P. M. after a violent Storm of Thunder, the Bituminous Matter fell upon the Stem of the Ship, and burnt there, emitting a strong Sulphureous Smell; and what was very remarkable, was that when Night came, they found, that the North Point of the Compass was become the South Point, and vice versâ. And, It was observed by a very famous Planter, that several Trees remote from one another, had very long and remarkable fissures in the Bark, upon great Storms of Lightning. TITLE XIII. Of Electrical Influences or Effluviums in the Air. SIR, Celestical Effluvia in the Air IN order to discover the several affections of Winy Liquors, and the several Distempers incident to them; and how to preserve them, it is requisite to consider the Qualities of the Air, it's Temperature and Motion. And this puts me in mind to beg our Friend's Assistance, who would do well to make some progress in perfecting the Theory of the Planets; for if that be not clear, we cannot be free from Errors in respect of their Motions and Calculations; and if we be mistaken in these, it's impossible to know either their Places in the Heavens or their Aspects, and consequently the Phisical way of their Motion must be uncertain, and of no use or advantage. But, tho' by some they are looked upon to have little or no influence upon our Globe, yet all the Arguments alleged against that Opinion, are rather leveled against Astronomy, in Relation to some Superstitions about this Doctrine, than that they show, why, when the Rays of each make different Angles upon one another, they may not at the last affect us. Since that they do is evident, by undeniable Experiments, not only on inanimate and vegetative Bodies; but likewise from the Observations of Physicians in all Lunatic, Epileptic, Paralytic or Lethargic Persons. And indeed, since Rarefaction and Condensation are mediate Motions, which dispose Bodies to Corruption, and are assisting in Generating New ones; and, since all the Affections and dispositions of Moisture, Heat, Cold, Drought, the Course of all Winds, Showers, Thundering, or whatsoever else is used by Nature, to produce these two General Effects of Rarefaction and Condensation, do in a great Measure, if not wholly depend upon, and are altogether regulated by the Course and Aspects of the Celestial Bodies, it will not be irrational to teach, that every one of those, emitting Rays peculiar to themselves have, by the Influence of those, different Effects on our Atmosphere: The subtle parts of the Air being not only subject to be worked upon by them, but likewise our Spirits, and other Humours, whose Parts, by the impression of these subtle Rays, may acquire a new determinate Motion, and consequently be altered, whence may arise Convulsions, Cramps, Lameness, etc. Accordingly as the Humours influenenced by them, are differently acted on, and disposed to show their ill Effects in this or that Part. So that it would be of considerable Import to Natural Philosophy, and of no small use in Husbandry, Gardening, as well as Physic, to make such Observations, as might tend to the of the Theory of the Planets by keeping exact Diàries in several Places, of the Changes of the Wether, and at the same time of the Mutual Aspects, places and Motions of the Planets; Besides, it would not a little conduce to the Perfecting of the Natural Histories of Countries, and particular Places. But in instituting and perfecting Observations of this kind, we are not yet Furnished with Thermometers, sufficiently improved; for, First, We are not yet acquainted, what Proportion the Diameter of the Cylinder ought to bear to the Diameter of the Head; to make our Observations of the Alterations in the Air, regular. Secondly, We are not told what Length the Cylinder ought to be; nor hath it as yet been well graduated, 16 being the greatest Number; whereas to make Observations on the more Minute alterations, every Inch may be divided into 10, and consequently the whole into a 1000 Degrees. Thirdly, We are not yet told what Liquors are most proper to make such Experiments with; Whether such as Attract the Air, and preserve their first Quantities; such as Ol. Sulph. per Campanam Ol. Vitriol. or Liquors, such as Sal Tartar, etc. or whether Liquors whose Parts are more subtle and fine, such as Spirit of Wine, or Turpentine; or Lastly, Spirit of Vinegar, or well refined Quicksilver. In making such Experiments, it may be convenient to fix several Glasses in one Frame, with several sorts of Liquors in them; and that Observations should be made in several Rooms together, the Glasses being neither exposed to the Sun Beams, nor to the injury of Storms, Rain or Winds. In the History itself it will be requisite to give an Account of the very place such Experiments were made in, taking Notice whether the Experiments are not influenced by the Air in the Chimney, the Cranny of a Wall or Door, or the Breath of People. It will be requisite likewise to note the Proportion betwixt the Warmth of Day and Night, in constant Wether: The agreement or disagreement of the Motion of the Air, and Bodies above it in uncertain Wether: How far these may foretell Winds or Rain; the disposition of Air, when it Thunders, under times of Mildews or Blasting, eminent Eclipses, Conjunctions. It is a Received Tradition in Java, that the Beams of the Moon, if one stays long under them, will cause Contractures; so that a Physician, who Slept under them, had his Mouth strangely contorted, and his Neck stiff, which Symptoms he removed sooner than they are wont to go off, by the use of Aromatic Medicines. TITLE XIV. Of the Height of the Atmosphere. TITLE XV. Of the Motion of Air, and of Winds. Storms of Wind. AT Porta Nova Nou. 22. 1667. There was so violent a Rain and Wind, that most of the Houses were Ruined; Men and Beast carried into the Water by the Violence of the Winds and Flood; the Town Wall was most of it thrown down and few Trees left standing. I am told that Hurricanes are very frequent about the Island Mauricius, where one lasted four days, in one of which it had seven Exacerbations, each of which differed two Points of the Compass from the Preceding; The surface of the Sea by the Collision of the Waves, was covered with a White Froth; the Day was darkened by it, and the Noise like, that of Thunder, so that those on the Shrouds could not hear those on the Decks. A Learned Physician, that Traveled into America, told me, that those Countries are supplied with a constant Wind from the Hills; but Barbadoes, which wants Hills, hath no such Winds. In the Island of Teneriff Breezes constantly flow from the Sea; but all Night, a sharp Wind blows on each side from the Land Seaward. I am told by a Traveller, that tho' the Tops of Mountains are generally calm; yet he had met with Winds considerably strong. In Lettere di Venetia MArtedi sui li 29. Agosto 1679. alle hore 19 incirca si levoleuò nelle Paludi della Villa di Favis del Dominio Cesareo tre miglia lontana da Palma Nova Dominio Veneto un ucnto chiamato Bissa bova, che allargandosi per circa cinquanta passi scorse con ●anto empito, e furore, che portò per aria diversi huomini, che tagliavano il fieno in quei Prati, e anco alcuni Carri carichi di fieno con i Buovi precipitandoli assai lontano con la rovina delli animali, de Carri, e degli huomini, e passando per i Campi sbarbicando ogni sort di Piante le portò per aria gettandole molti passi lontano, rendendo la terra per oue scorce cosi arsa, che pair non vi sii mai stata piantata cosa alcuna. Arriuò nella villa decta Bagnaria del Dominio Veneto dove gettò a terra molte Case sino a fondamenti, et alter discoperse, e rovinò portando per aria tavole, travi, et ogni altra cosa che era dentro esse Case restando mal trattate molte Person senza però la morte di alcuno. Fuori di dettata Villa vi e una Chiesa chiatata S. Tomaso la quale resto scoperta, e rovinata una parte del muro portando via il Campanile, e Campane che nel giorno seguente non erano per anco trovate;— Di lá si portò verso Seuigliano Dominio Veneto e rovinon tutta la Campagna senza danno però della Villa stessa mentre li passò poco lontano, e girando poco lungi dalla Villa stessa spiantò da fondamenti un Palazzo del D. Co. Horatio Strasoldo, nel quale gli amazzò ogni sort di ànimali i vi erano, portando per aria li mobili e sino le botti, esterminando parr della possessione. Non restorono però offese Person, perch erano alla Campagna a lavorare, e nel camino getto pure a terra due alter Case che sono nel Taglio per andare a Strasoldo spiantandole affacto con la morte di una Donna, d'un Fanciullo, e diversi Animali. Diego là voltò verso Palma, et arrivando sino alle mura della Fortezz agirò verso la Villa di Privano mezo miglio distante quale rovinò la meta, spiantando da fondamenti belissimi Palazzi, portando per aeria travi, tavole, et ogni altra cosa con la morte di molti, quantità di feriti, e diversi strapazzati con far alla Campagna di molto male. Di poi scorse nella Villa di Visco Dominio Imperiale, e tra li altri danni fatti roninò tutto il Palazzo novo del D. Marco Foscolini Gentilhuomo di Cinidal nel quale essendoni una gran rimessa da Carozze, la di cui Porta havena tre Cadenazzi, & entrando il Turbine per li balconi gettò la Carozza con tanto empito nella Porta siessa che la ruppe, e portò fuori la Caroza tutta fracassata gettandola sopra un muro della Corte assa alto, portando il Cielo della stessa mezzo miglio lontano, e vertò nel medemo Palazzo ferito, e mal trattato un seruitore di esso Foscolini, di cui ronino pure Braida, & un Brolo essendo in detta Villa restati due morti, e diversi feriti;— SH' inoltrò poi nella Villa di S. Vido di Crauglio stato Imperiale, la quale rovino tutta affatto senza restaurui nemeno una Casa, portando per Aria coppis, travi, legne, sassi, e mobili con la morte di moltissime Person, e moltissimi feriti e rovinati, et in detta Villa non si può anddare, ne con Carri, ne con Cavalli per la grande moltitudine di rovinazzo, arbori et altro che hanno attaver-sato le strade, essendo rimassi morti gran numero di animali.— Da questo luoco si portò verso Villes Villa Imperiale buona parte della quale gettò a terra andar al. Territorio di Monfalcone con la morte di molte person, et quantità di animali con lasciar le Campagne per dove è passata senza piante, e come strada battuta.— Hà danneggiato anco alter Ville ma leggiermenre, ne per anco si sá quello haverà fatto piu avanti nel detto Territorio. Questo successo hà lasciato un spavento grande in quest Parti, essendosi vedute cose incredibili mentre piovevano sassi, tavole, arbori, travi, coppis, huomini, donne, fanciulli, botti, sorghi, uva, galline, animali, et in conclusione ciò che incontrava portava per aria con un rumore, e fracasso così gradne, che faceva terrore essendo per debt Ville un concorso grande di Popolo vicino per vedere cose che si rendono incredibili. I am told, that tho' the Eastern Winds blow near Tangier about ¾ of a Year, yet they reach not into the Inland Country; where such Winds are not common. I am told by one who observed it in the Bottom of a Mine near the Sea, that before South Winds the Water would be troubled, but before East Winds it would be clearer than ordinary, the Depth of the Mine was about 15 or 20 Fathom. He told me likewise, that the Hurricanes at Goa, come but at two Seasons; about the beginning of March, and the 4th of October. TITLE XVI. Of the Air as the Medium of Sounds, and of Sounds and Noises in the Air, and Particularly Thunder; and of the Airs Operation on the Sounds of Bodies. Of the Air as the Medium of Sounds. UPon the Rising of several Tempests together, the Sky seems covered over with Globes of Smoky Clouds, the Air seeming black and Thick; and by and by incessant Lightning, with terrible loud Thunder breaks out; Ludolph's History of Aethiop. l. 1. c. 5. A Viol. String hath been Observed, upon Rainy weather, to sound half a Note sharper than before, and, I am told by the same Person, that having kept false Strings in his Pockets for some time after, they became true ones; and the same Person hath Observed, that some Strings are apt to Receive a Tension, than others. TITLE XVII. Of the Weight of the Air The Weight of a cubical Inch of Water. HAving placed a hollow Cube of Brass, every side of which was an exact English Inch, in a pair of Scales as Horizontally as we could, It's Weight being ʒxi. gr. 1. ss. we filled it with common Water, and then, besides the Counter-poise of the Brass Cube, the Water weighed 254 ●/● Grains; and since it is a hard Matter to fill the Vessel more exactly than we did, I judge that a Cubick Inch may way, 256 Grains. Of Quicksilver. A Cubick Inch of Mercury weighed in the same Brass Cube was 3580 Grains, which is to the Weight of Water, as 14 to 1 Of a Pillar of the Atmosphere. The Weight of the Air incumbent on an Inch Square of Air here below, amounts to 18 l ½ Troy-weight, i. e. 15 l. 1/17 Averdupois-weight. As 11 to 14. or rather as 355. to 452, so is the Area of a Square inscribed in a Circle to the Area of the Circumscribed Circle. Hence 355: 452 ∷ 1: 1, 2732394. Hence if the side of a Circumscribed Square be an Inch, that Multiplied by an Inch, renders a Cubick Inch for the Solid Content. In the like manner, if the Height of a Cylinder Erected on the Circumscribing Circle, be an Inch, the Solid content of that Cylinder is, 1, 2732394. Wherefore 1, and 1, 2732394, Multiplied, by the Weight of the Cubick Inch of any kind of Metal, give the Weight of a Cubick Inch, and of a Cylindrick Inch that Circumscribes the same; whence an Inch Table for both is easily made, by contiunal addition, or for any Height propounded, Multiplying both by the same. See Plate 6. Fig. 4. LE Tuyan recourbé estoit fermé au bout ae et Ouuert alautre extremité B. La. recourbure depuis G. jusq' a C. estoit pleine de Mercure & tout le reste estoit plein d'air. La longueur AE.C. estoit 4. Pouces' ou 32/8. J'echauffay cet air, et il feit baisser le Mercure Jusques en f. qui estoit ⅜ plus bas, & en mesme temps il monta jusq' en H. qui estoit ⅜ plus haut que G. ou C. Pour sçavoir quélle hatetur de Mercure auroit este necessaire pour empescher la dilatation de lair, & retenir le mercure en C. je nay quá trower ce qui seroit necessaire pour repousser le mercure en C. Etainsy contenir lair dans léspace A C. non obstant la Chaleur. Jepose pour principe ceque lexperience fait voir, Cest que quand une quantitè dáir occupe un certain espace que jáppelle A et que la pression qui leretient dans cet espace soit B. si on vient a augmenter cette pression de telle quantité que lón voudra comme X. on diminuera l'espace A d'une certain quantité D. Laquelle quantité est au restant M. come X est a B. D. M ∷ X. B. donc. M. D ∷ B. X. Il est aiséd áppliquer cette reigle à lexperience cy dessus. Car A f. ou 35/8 de pouce sont lespace A Lapression ordinaire de lâir qui est de 30 Pouces. Jointe nae un pouce de haut que se trouue entre. f et H. est B X 31 Pouces de Mercure: et si nous y en adjoustons assez pour reduire lair a léspace A C. Le dit A C. sera M. X 32/8 Et. f. C. sera D. X ⅜ Posant donc. M. D. B. 32. 3. 31. La quatriesme propotionelle sera X. X 2 29/32 pouces, qui estants joints a B. X 31 Pouces feront 33 29/32 pouces dont láir sera pressé en C. A qui sont pres de 4 Pouces au dessus de la pression ordinaire. An Experiment made at the Spire of the Cathedral Church in Sarum. HAving procured all the Surveying Chains we could, and a proper Frame for a Baroscope, we went into the Church, where when the Tube was inverted, as in the Torcellian Experiment; the Mercury stood at 30 Inches, and 50 Centesms of an Inch: Being drawn up to the first floor which is 1033 ½ Inches, it subsided 9 Cents of an Inch; being drawn up 935 Inches higher, it sunk 8 Cents more; being drawn up 2313 Inches higher yet, it lost 23 Cents, and when it was let down again the Mercury reascended to it's former Station at every one of the Marks. At another time an inverted Baroscop being made use of, such as Plate 5, Fig. 6, delineates, having set a Mark where the Mercury stood below, when it was raised. Inches Inch. Cent. 1033 ½ The Liquor Ascended 1 25 1●68 2 39 2467 3 22 4281 5 64 4800 or 400 feet 6 40 On the great Continent not far from the Sea, before a great Storm, in which the Wind blew along the Continent, the Mercury was Raised two Inches above its usual Station; but when the Wind blew from the Sea, the Mercury subsided; which hath been observed by another Gentleman in England, where in the Inland Parts likewise the Mercury subsided before a Storm. An Extract of a Letter writ to the Author, by the Ingenious Author of that most incomparable Essay of Human Understanding Mr. Lock, Dated Ch. Ch. May 5th 1666. An Account of Minedeep Gruffs. IN the Letter we are informed, that designing, at the Request of Mr. boil, to try some Barometrical Experiments in the Gruffs at Minedeep, when he came there, he found it neither safe nor easy, for one not accustomed, to go down into them; for the Descent not being Perpendicular, but crooked, as the Crannies of the Rocks gave them way easiest in sinking their Pits, they are forced to clamber up and down the Narrow Passage, by setting their Hands and Feet against the sides of it, all the Assistance besides, being a Rope which they take under their Arm; besides, sometimes when they are down, the Damps catch them; and if they cannot get out speedily, they fall into a Swond and die: The only Remedy which Recovers them is this, they first Dig a hole in the Earth for their Faces, and then cover them close with Turffs. To force Air into these Gruffs, they place Turfs on the Lee side of the Pits Mouth, instead of which, if they be plaon the other side, those in the Gruffs are seized with a want of Breath and Fainting. Sweet Flowers being taken down into them, presently Stink. And it is likewise observed, in these Gruffs, that it is very dangerous to descend into them, when any Fire remains in the Chinks of the Rocks; for they usually make such Fires upon hard Rocks, that they may more easily Dig through them. The Torrecellian Experiment being tried, on a Steep Hill, the Mercury at the Bottom was suspended at 29 Inches and ⅛; at the Top of the Hill it subsided to 28 ¾, where both as I ascended and descended, the Mercury gradually subsided and risen again; only the Sun had so far Rarified the Air above the Mercury, that when the Tube was brought to the bottom again, the Mercury wanted 1/32 of its former height, which I suppose depended on the Resistance that Rarified Air made to the Pressure of the Atmosphere. Having visited the Incrusting Spring, I formerly mentioned, I observed, that about the Springhead there was only a little Moss Incrustated; but 40 or 50 Yards of it, where the Water hath a Fall higher than my Head, it Sheathed every thing with Stony-cases, and makes the sides of the Banks hard Rock. It bears Soap, Freezes Quickly, and Water's Ground with advantage; It is used in the Kitchen and Brewhouse belonging to the Gentleman, in whose Ground it Rises in, without any sensible ill Effects; only his Horses are Observed to be usualshort Breathed. Thus for the Extract of Mr. Lock's Letter. Some days ago the King doing me the Honour to Discourse with me about the use of Baroscopes, he told me, that he himself had by observing the Baroscope, foretlod a Storm, which accordingly ensued. Nous apprenons de ces experiences, que puisque le poids de l'Air et le poids de l'eau qui est dans les Pompes se tiennent mutuellement en Equilibre, ils pesent precisement autant l'un que l'autre; & qu' ainsi en connoissant la hauteur ou l'eau s'élve en tous les lieux du monde, nous connoissons en mesme temps combien chacun de ces liex est press par le poids de l'Air qui est au dessus d'eux; et partant. Que les lieux qui sont au bord de la mer, sont pressez par le poids de l'Air, qui est au dessus d'eux jusques au haut de sa Sphere, autant precisement, que si au lieu de cét Air on substituoit une colomne d'eau de la hauteur de 31 Pieds deux poulces. Ceux qui sont plus elevez de dix toises, autant que s' ils portoient de l'eau de la hauteur de 31 Pieds un poulce. Ceux qui sont élevez au dessus de la mer de 500 Toises, autant que s' ils portoient de l'eau à la hauteur de 26 Pieds onze poulces: & ainsi du rest. Nous apprenons par ces experiences que l'Air qui est sur le niveau de la mer pese autant que l'eau, à la hauteur de 31 Pieds deux poulces; mais parce que l'Air pese moins sur les lieux plus elevez que sur le niveau de la mer; et qu' ainsi il ne pese pas sur tous les Points de la terre egalement, & mesme qu'il pese differemment par tout, on ne peut pas prendre un pied fix, qui marque combien tous les lieux du monde sont Chargez par l'Air, le fort portant le foible; mais on peut en prendre un par conjecture bien approchant du just; comme par exemple, on peut fair estate, que tous le lieux de la terre en general considerez comme s' ils estoient également chargez d'Air, le fort portant le foible, en sont autant pressez, que s' ils partoient de l'eau à la hauteur de 31 Pieds; et il est certain qu' il n'y a pas un demy pied d'eau d'erreur en cette Supposition. Or nous avons veu que l'Air qui est au dessus des montagnes hautes de 500 toises sur le niveau de la mer, pese auntant que l'eau à la hauteur de 26 Pieds 11 Poulces. Et par consequent tout l'Air qui s' étend de puis le niveau de la mer jusqu' au haut des montagnes, hautes de 500 Toises, pese autant que l'eau à la hauteur de 4 Pieds un poulce, qui estant à peu prés la septiéme party de la hauteur entiere; i'll est visible que l'Air compris depuis la mer jusques à ces montagnes est à peu pres la septiéme party de la masse entiere de l'Air. Nous apprenons de ces mesmes Experiences, que les vapeurs qui sont épaisses dans l'Air, lors qu'il en est le plus Chargé, pesent autant que l'eau à la hauteur d'un pied huit Poulces; puisque pour les contrepeser, font housler l'eau dans les Pompes à cette hauteur, par dessus celle ou l'eau contrepesoit déja la pesanteur de l'Air: de sorte que si toutes les vapeurs qui sont sur une contrée estoient reduites en eau, comme il arrive quand elles se changent en pluye, elles ne pourroient produire que cette hauteur d'un pied huit poulces d'eau sur cette contrée. Et s' il arrive par fois des orages ou l'eau de la pluye qui tombe vienne à une plus grande hauteur; c' est parce que le vent y porte les vapeurs de contrées voisines. Nous voyons aussi de là, que si toute la Sphere de l'Air estoit pressée & comprimée contre la terre par une Force qui la poussant par le haut, la reduisist en bas à la moindre place qu' elle puisse occuper, & qu' elle la reduisist comme en l'eau, elle auroit alors la hauteur de 31 Pieds seulement. Et par consequent qu' il faut considerer toute la masse de l'Air en l'estat libre ou elle est, de-la mesme sorte que si elle eust este autrefois comme une masse d'eau de 31 pieds de haut á l'entour de toute la terre, qui eust esté rarefiée et dilatée extremement, et convertie en cet estat ou nous l'appellons Air, auquel elle occupe à la verite plus de place, mais auquel elle conserve precisement le mesme poids que l'eau à 31 pieds de haut. Et-comme il n' y auroit rien de plus aisé que de suppter combien l'eau qui environneroit toute la terre à 31 Pieds de haut peseroit de liures; et qu' un enfant qui scait l'Addition et la Soustraction le pourroit fair; on trouveroit par le mesme moyen combien tout l'Air de la Nature pese de livres, puisque c' est la mesme choose; et si on en fait l'épreuve, on trouvera qu' il pese à peu prés huit Millions de Millions de Millions de livres. I ay voulu avoir ce plaisir, et j' en ay fait le compte en cette sort. I ay supposé que le Diametre d'un cercle est à sa circonference, comme 7 à 22. I ay suppose que le Diametre d'une Sphere estant multiplié par la circonference de son grand cercle, le produit est le contenu de la superficie Spherique. Nous Scavons qu' on a divise le tour de la terre en 360 degrezes. cette division à esté voluntaire, car on l'eust divisée en plus ou moins si on eust voulu, aussi bien que les circles celestes. On a trouve que chacun de ces degrez contient 50000 toises. Les lieues autour de Paris sont de 2500 toises; et par consequent il y a 20 lieves au degré: D'autres en comptent 25 mais aussi ils ne mettent que 2000 toises à la lief; ce qui revient à la mesme choose. Chaque toise a 6 pieds. Un pied Cube d'eau pese 72 libres. Cela pose, il est bien aise de faire la supputation qu' on cherche. Car puisque la terre a pour son grand cercle, ou pour sa circonference 360 degrezes. Elle a par consequent de tour 7200 lieuves. Et par la proportion de la Circonference au Diametre aura 3291 lieves. Doncen multipliant le Diametre de la terre par la Circonference de son grand cercle; on trouvera qu' elle á en toute sa superficie Spherique 1649200 lieves quarrées. C' est à dire 103, 095, 000, 000, 000, toises quarr. C est à dire 3711, 420, 000, 000, 000, pieds quarr. Il's ensuit qu' un pied cube d'eau pese 72 livres. Et parce qu' un prisme d'eau d'un pied quarre de base, et de 31 pieds de haut, pese 2232 livres. Donc si la terre estoit couverte d'eau jusques à la hauteur de 31 pieds; il y auroit autant de prismes d'eau de 31 Pieds de haut, qu' elle a de Pieds quarrez en toute sa surface. (je scay bien que ce ne seroient pas des prismes, mais des secteurs de Sphere; et je neglige exprés cette Precision.) Et partant elle porteroit autant de 2232 liures d'eau, qu' elle a de pieds quarrez en toute sa surface. Done cette masse d'eau entiere peseroit. 8283, 889, 440, 000, 000, 000, liures. Donc toute la mass entire de la Sphere de l'Air qui est au monde, pese ce mesme poids de 8283. 889, 440, 000, 000, liures. C' est à dire, Huit Millions de Millions de Millions, deux cent quart vingt trois Mille huit cent quatre vingt neuf Millions de Millions, quatre cent quarente Mille Millions de liures. Mr. Pascal in his small Tract, either Dela Pesanteur de l'Air; or in that Del'Equilibre des liqueurs. See Plate 7 Fig. 4. De caetero, feci haud ita pridem experimentum ponderandi aeris, quod pulchré successit; nam sumptâ vitreâ lagenâ, valde levi et ad lampadem sufflatâ, ejus figurae, qualem alibi excusam vides, magnitudine parvae pilae quales habentur in sphaeristeriis, non habente nisi minimam quandam aperturam per quam immittatur pilus in extremitate orificii sui B. ponderavi eam in lance valde exacta, & frigida pondus habuit 78 granorum cum dimidio: Postea calefeci eam carbonibus impositam, & reposui in bilancem eo situ quo hic descriptum vides, nimirum orificio in imum verso, & deprehendi eam vix habere pondus 78 granorum, tum immergendo orificium in aquam, refrigescere feci, & dum aer se condensat pro modo quo refrigescit lagena, intravit tantundem aquae quantum aeris calor antea expulerat; denique ponderans eam cum omni illa aqua deprehendi eam habere pondus 72 granorum & dimidii plus quam antea: unde concludo aerem qui per ignem expulsus erat, se habere ad aquam quae in locum suum regressa erat uti ½ se habet ad 72 ½, aut uti se habet 1. ad 145. sed potui in eo errasse difficile, quippè est in ea re omnino exactum essée; Id saltem certò scio, quòd pondus aeris hoc modo sit sensiblile, & prolixe hic deduxi processum meum, ut si te eadem curiositas incessat, possis id eodem modo perficere experimentum. Vale. TITLE XVIII. Of the Consistency of the Air; it's Rarity, Density, Fludity, Subtly. Of the Consistency of the Air, etc. A Thin, but large Bladder, having a third Part of the Air, it was capable of containing, remaining in it, had its Neck strongly tied; and at the other end a Weight was suspended of 14 Pound by a String, which could not shrink ¼ of an Inch, without raising the Weight from the ground: But the Air in the Bladder was so far expanded by heat, that the Weight was raised, and would swing in the Air like a Pendulum. The same Experiment being tried with a 50 pound Weight, before the expanded Air was able to raise the Weight, the Bladder would burst. To try whether the Corpuscles of the Air would penetrate into a Liquor exposed to the Ordinary pressure of the Atmosphere, we poured a Urinous Spirit upon as much Filings of Copper, as covered the bottom of a Cylindrical Vial, so that the Spirit was the Breadth of 3 Fingers above the Filings, which being done, on that, we poured so much Oil of Almonds, as covered the Spirit the Thickness of a Crown piece; upon which the Vial being kept some days in a quiet place, the Urinous Liquor did first acquire, and then lose a blue Tincture. When the blue was in a great Measure vanished, the Bottle was kept unstopped a Minute, and then stopped again; in a short time the Urinous Spirit was tinged with blue, which Colour in an hour extended itself all over the Liquor, the Oil upon the Top of it still remaining clear. TITLE XIX. Of the Heat and Coldness of the Air. TO show that it is not without Reason that I Question what the Peripatetics teach about the Limits and Temperaments of the Air, which they divide into three Regions, I shall propose the following Particulars. The Air at Morocco, tho' excessive hot in the Day is Cold at Night, as well as the Mountainous Parts thereabouts. One, who stayed a Year in Guinea, tho' it is excessive hot, told me, that about 4 a Clock in the Morning, he was ready to tremble with Cold. One told me, that in Jamacia, when he lay in his Hammock about 3 or 4 Foot from the Ground, tho' he had much under him, yet he perceived it Cold beneath, and Hot above. So that to show that not only Liquors, and Animal Bodies may be affected with the Summer's heat, but even Glass itself, I shall intimate, that Glass-stopples of Factitious Crystal being so fitted to Viols of the same, tho' in Winter they would move about easily; yet in the Summer they would not be pulled out by the Assistance of a String, till the Expansion of the Glass was taken off by being cooled in Water. I am apt to believe, that several Effects, which we are apt to attribute to the Heat of the Air, putting the Parts of the Juices of our Bodies in Motion, depend on some Effluvia raised by Heat from other Bodies, and which swim in the Air. A large Piece of Amber being placed in the Summer in the Sunbeams, had its Parts put into such an Agitation, as enabled it to emit Electrical Effluvia, and to attract light Bodies, which Power it would lose when removed out of the Sunbeams again. Mr. Nickson told me, that, near Hudson's Bay, when they were a Leeward of certain floating Islands of Ice, they were sensible of it by a new Access of Cold; before they approached so near as to see them, which was at 20 Miles distance. He likewise told me, that that Wind brought along with it a Foggy Air; And that in that of Hudson's Bay where he wintered, the Rivers were not free from Ice from the latter End of October, to the middle or end of May, tho' the Latitude of Charlton Island, most frequented by the English was of the same Latitude with London, and at the most not exceeding 52 Degrees: The Ice was near six Foot deep; and the Frost so violent, that Bottles of Brandy would have a fourth Part turned into Ice, the unfroze Liquor being much stronger than before: The Ice which swum upon the Water was fresh, from whence they supplied themselves with fresh Water, either by melting it in their Pots, or by gathering it from large Cavities in floating pieces of Ice, where it was melted by the Sunbeams. A Traveller told me, that upon the Top of a Pyrenean Mountain in the Summer it was very hot, tho' the same Day it was covered with Snow; and another told me, that the Winds at Morocco were so hot, as almost to stifle him. And it hath been observed, upon the Tops of high Pyrenean Mountains, that, below them there were Clouds which yielded Rain plentifully, out of which Lightning flashed upwards as well as downwards. Dr. Stubbs told me, that in a Bolt-head about 2 Foot ½ long, about 7 or 8 a Clock in the Morning, which is the faint time of the Day, the Water would rise but ¼ of Inch and half a quarter, after which time it would subside till that time the next Day. He further added, that in 8 or 10 months' time in that hot Country, Water would not decrease in Quantity, tho' kept unstopped. I am told by another, that in the Torrid Zone near the Coast of Sumatra, tho' Ice nor Frost nor Snow are ever observed, yet he hath known Hail to fall. And I am told, that in the Island of Ceylon, which lies betwixt 6 and 10 Degrees North Latitude in that Torrid Climate, it would be so cold at the Top of some Hills, to whose Tops they could ascend in half an hour, that they would almost shiver. And Capt. Knox told me, that having spent 18 Years in that Island, he observed a kind of Meteor in Winter's Mornings between a Dew and a hoar Frost, which presently vanished; and that once there happened a shower of Hail, which were about the size of a black Cherry, but were presently melted upon the Ground. The Heat is so violent in the Island Suaquena, that it excoriates the Skin, melts Indian Wax in a Cabinet, and sears your Shoes like a red hot Iron. Yet on some Mountains in Aethiopia, they dread Cold more than Heat; tho' no Snow falls, but only a little Hail now and then, which soon melts; and Tellesius witnesses, that in many Regions in Aethiopia, the Air is more mild than in Portugal, so many Degrees distant Northward. At Tripoli in Barbary it is observed, that when the Wind blows over a long Sandy Desert, it, as well as the Wind it brings along with it, seems as hot as the Steams from an Oven: And and the same hath been observed near the Island of St. Lovis, on the Coast of afric; where it was further remarkable, that the Ground was so hot, that the Gentleman, who related it, could scarce endure to stand upon it; and he further told me, that when the Wind blew from a Wood, in which the dead Bodies of Wild Beasts lay, it stunk so that it could scarce be endured. In summo ejus montis, Idae sc. fastigio sacellum est, quod aedificiolo duntaxat constat saxis sibi invicem impositis & sine calce cohaerentibus fornicis in modum constructo, ad tectum praebendum. Sublimi adeo loco est, & à vehementioribus ventis interdum ita perflato, ut lapilli inde transferantur. Petri Bellonii, lib. 1. cap. 16. Paulo infra id sacellum planities conspicitur montibus undique cincta, in quâ multa sunt pascua, ubi Arietes & Caprae Cretenses aestate pinguescunt. Si quis ex summo montis vertice undique prospiciat, p●●●… aberit, quin totius Insulae ambitum videat cum 〈◊〉 vicinis Insulis, Miso, Cerigo, sive Cythera, 〈◊〉 Archipelagi. Aeris intemperies in hoc ●●●…te adeo magna est quemadmodum ut in caeteris prae●●●… montibus, ut in ipsis Caniculae ardoribus ●…ridie▪ nullo etiam spirante vento, ingens sen●●●tur frigus: qua de causa nec hyeme, nec asl●…te 〈◊〉 eum incolit. Nam licet pastors interd●…●●i●● greges ad pascua agunt, noctu tamen in valles se recipiunt. In the next Chapter. Latè porro patet hic mons ejusque radices 〈◊〉 maris littora, ut ante diximus, attingunt; nam licet urbi Candiae sunt vicinae, meditullium tamen insulae occupat ipse mons, adeo in sublime evectus, ut nives ejus verticem perpetuò tegnant; tamque frigida a●ra mediis etiam astatis ardoribus isthic est, ut vix ferri queat: tametsi in convallibus magnus sit aestus. Jacobi Zabarelli de-Regionibus Aeris, c. 8. Contigit id meae experientiae, quod etiam aliis contigisse audivi, ut ascenderem ad summutatem usque montis Veneris, qui omnium in Patavino agro altissimus est; ibi per totum diem habui Aerem serenissimum, sed infra circiter medium montis vidi nubes, quae me visione vallium prohibebant, vesperi autem postquam de illo monte descendi, inveni factam eo die infera parte magnam pluviam cum in montis cacumine nihil pluisset; ex eo intellexi me transiisse per mediam Aeris regionem, in qua est facta pluvia, nec tamen eam sensi frigidissimam, imò vix aliquam animadverti differentiam frigidioris & calidioris Aeris, nam aestivum tempus erat, pro aestivo tempore eram vestitus, nec tamen tantum frigoris, quod me laederet, ex eo loco percepi; pars igitur illa non est absolutè frigida, sed solùm comparatione inferi, Aeris calidioris. Idem de Alpibus proprio exemplo edoctus testatum reliquit Bartholinus Syst. Phys. Instit. Succinct. de Terra, Aere & Igne, C. 4. Resp. 1. Mount Atlas in the Heat of Summer hath been seen covered with Snow; and several People who have visited the Tops of high Mountains, such as the Alps and Teneriff, have found it exceedingly cold. I am told by one, that he never heard of Snow or Ice in Guinea; but in Barbary, where the Plains were excessive hot, the Tops of Mountains were covered with Snow, and the like hath been observed in the Island Ceylon, and the Mountains of Congo. In the Summer 88, I placed a Glass in a Cave, which faced the Sea, it being covered with 80 Foot of Earth, and cut right in about 130 Foot, the Mercury stood ½ above Temperate; and at the same time, in another Glass in the open Air it stood at hot: About Christmas following the Mercury in the Cave varied not, but that without stood at Frost. In New-Hampshire in New-England it is observed, that in the Winter the North-West Wind is very cold, and in Summer intensely hot; It is ascribed to a large Tract of Woody Land, which in the Winter is covered with Snow, and in the Summer, the Valleys being close, keep in the Heat till it becomes very violent. Balbini Hist. Bohem. l. 1. c. 9 Demontibus, & de valle Lavezka, p. 29. Chanowsky in vestigio Boh. piae, C. ult. Montes parte eltera aestatem, altera hicmem referentes. De montibus ad Bavariam stantibus mira est Alberti Chanowii nostri narratio: Post Bergreichensteinam (oppidum fodinis hodieque nobile) esse montes non tam situ (alii enim ad septentrionem, alii ad meridiem latus obvertunt) quam Coelo & temporibus adversantes, vallibus latissimis montes illos dirimentibus; monstri instar est (quod se vidisse, & Anno 1639. in rem praesentem venisse religiosissimus ille & Apostolicus vir asserit) in altero monte saepius aestatem, in altero apposito hiemem dominari, it a ille succus aestivat, hic altissimis nivibus obsitus à viatore superari non potest; ob eamque causam Messes ipsae variant, & dumb in montibus ad nos obversis demessa sunt omnia, Id. Ibid. altera Montium parte seges virescit: Mirius illud quod in Biessinentibus & Czachroviensibus Agris in tractu Plsnensi, contiguis, quos unus tantum sulcus dirimit ac dividit, deprehenditur: Czachrovienses adhuc hibernant, cum in Biessinensi Coelum ardeat, ibi caput attollit humo frumentum, cum Czachrovii adolescit in culmum; clemento quoque dispari, illud riget, hoc tepet & ferve●, eâque ex causâ, dum Czachrovienses bene pelliti ingrediuntur, Biessinenses pellibus onerari se sentiunt, villosque deponunt. Aliquid tale Anno 1652. mihi quoque accidisse memini: nam cum Glacio Zambergam in Bohemia contenderem, & Glacio ob nives altissimas certum vehiculi genus, quod trahas dicimus, sumpsissem, superatis montibus, qui comitatum Glacensem à Bohemia dividunt, subitò alia rerum facies apparuit: altero enim montium latere viridia omnia reperimus, sic ut Trahae nulli jam rei & usui essent, & currum petere cogeremur, nisi in luto natare placuisset; at accolae montium illorum quotannis id sibi accidere confirmabant, ut unum latus montium profundissimae nives contegerent, quando alterum latus lectissimos flores proferret, & cum ibi omnia ventis verti viderentur apud se è floribus suavissimos odores efflari. I was told by a Gentleman, who several times went down into the Hungarian Gold Mine at Cremonitz, that when he was drawn up the Groove, which was 'bout 100 Foot deep, as soon as he ascended half the way, he perceived the Air sensibly warmer, which continued several Feet nearer the Day; in which Region he observed, several Veins of Native Vitriol of different Colours, which were soft under Ground, and being exposed to the open Air, presently hardened. Under the Torrid Zone the Mariners, I am told, hang up their Bottles of Liquor in a Linen Cloth, that the Wind may blow upon it, by which means it would be cooled enough to make it fit for drinking. The Heat of the Sun is so violent in some Parts of Moscovy, Norway and especially at Mozambique, that it often sets the very Houses on fire; which I the less wonder at in the latter place, because they build their Houses with a Stone that abounds with Sulphur Viu. When the Sun is in the Zenith, the sandy Ground is so hot, that they can scarce endure to tread on it. Vn Gentilhomme de mes amis plein de merit & digne de creance me manned entre plusieures choses extraordinaires qu'il a obseruées proche de Barege aux Pyrenées, qu'il y a des ponts de niege d'un rocher à lautre pardessous les quells passent des torrents. Il en a vu un qui embrasse deux torrents, & qui a vint neuf toises de long & autant de large par dessus. Il y a par dessous ce pont Neuf toises & demi entre les Naissances de la voute les ponts sont tellement forts qu' il estime que du Canon y passeroit, & il a fait rouler de grosses pieces par dessus. Le tremblement de Terre que souffrit la Syrie l'an 750. ne fut gueres moins surprenant; puisque la Terre s'estant ouverte de toutes parts, plusieurs Villis furent abîmèes, d'autres renversées, & quelques unes qui estoient eleuées sur des hauteures transportées dans des plaines eloignées de six mille de leur situation. On en peut dire autant du froid extreme qui l'an 753. glaça le Pont-Euxin a la longueur de cent mille, & toute l'estendue de la mer voisine, jusq' à 30 condées de profondeur, quoy qu'on ne fût encore qu'au commencement de l'automne. Journal de Scavans III. 1685. It is the Custom at Guinea to cool their Water by burying it all Night under Ground: And on the contrary in some Places it is so excessive Cold, that in the Woods, it would freeze our Eyelids; the outside of the Houses would be half covered with Snow, and Icicles would hang on the Insides; the on our Beds would be covered with a hoar Frost, and Water which stood near the fire, would have one side hot, and the other froze: The Sea would be froze up till the beginning of June, and the Ground till the beginning of July. Capt. James. I was told by one who ascended to the Top of the Picinino de Medi, a Pyrenean Mountain, that tho' the North side was covereed with Snow, yet the Heat of the Sunshine could scarce be endured on the South side; this Hill is so high, that it may be seen from Montauban 27 Leagues distant. An Ingenious Physician told me, that tho' Jalap at Tangier might be reduced to Powder; yet at Morocco it was so melted by the Heat of the Air, as to become incapable of being powdered. Nell capo di comorino si termina cosi I' esta, come I' inverno dalla parte, di la dal capo verso Notte, & dal'altra parte correspond illi ●●mpo assai contrario è eiverso, di maniera che, chi va navigando, per quella costae nel mese di Ottobre, sino ad Aprile naviga nel esta, è non puo in tutto questo tempo, passare il capo per Esser ivi la stagione del inverno, & il Puere, i resiede nelle Chies ch' appartengono all Capo di Comorino ne Alcune la state, il che e cosa di gran Meraviglia, essendo cio nel medessimo tempo nella distanza sola ment di due, o tre miglia. An eminent Virtuoso descended into a Mine in Tirol 1800 Foot deep, without taking notice of any hot Region by the way; and at the Bottom the Air was so temperate, that notwithstanding what is said of Antiperistasis, no intense Cold was retreated thither to shun the Heat of the superior Air. One that descended into several Mines in England, observed it sensibly colder, when he was about a Yard below the Fast, as Miners call that solid Earth, which they distinguish from that loser Earth that lies above it, in which Plants and Trees spread their Roots, they seldom reaching to, or penetrating into the Fast, tho' sometimes it lies near enough the External Surface of the Earth. An Exact Relation of the Pico Teneriff. A relation of Mount Teneriff. The Gentlemen who gave the following Account, set out from Oratava, a Town situated on the North side, two Miles from the Sea, and in 8 hours got to the Top of the first Mountains, to wards the Pico de Terana, from whence the Company proceeded over sandy and lofty Mountains, which were not covered with Pine Trees as the first 8 hours' Passage was: This Way continued till they came to the Foot of the Pico, where they found very large Stones, which seemed to have fallen from some superior Part. Thoughts concerning the cause of its stupendous Bulk. It is thought by Dr. Pugh, that the whole Soil in that Island being sulphureous, did take fire, and most of it Blew up at the same time; in which general Conflagration, he supposes, those many Mountains of calcined Stones which lie up and down the Island, but especially the South-West Parts of it, were cast up; and the greatest Quantity of Sulphur lying about the Centre of the Island, raised the Pico to that Height, which it now remains at. On the South-West side these calcined Rocks lie one upon another from the Top of the Pico to the Sea shore, but very few on the North; so that he supposes the Vulcano chief discharged itself that way; several of these calcined Rocks resemble Iron Over; some Silver, and others Copper; especially in the South-West Parts called the Azuleios, there are vast Quantities of a bluish Earth, intermixed with blue Stones, which are covered with a yellow Rust, like that of Vitriol or Copper; and he was told, that a Bell-Founder of Oratava got pure Gold out of two Horse Loads of Earth; and he was further told by another, that a Lump of Earth brought from the Top of the Mountain, yielded a good Quantity of Silver. About this Mountain are likewise observed, several Vitriolate as well as Nitrous and Martial Springs. To confirm this Notion of the Reason of what he observed, he alleges, that the very Tracts of the Torrents of Sulphur which ran down from the Mountain are yet visible, which did so much Damage to the Ground it flowed upon, that nothing but Fern is able to grow upon it. But what seems further to confirm his Account is, The Instance of the Palm Island 15 Leagues from Teneriff, where upon the firing of a Vulcano, the Earth shook terribly, and the Torrents of flaming Sulphur made as loud a Noise as Thunder; and the Light of it made the Rooms as light all Night for six Weeks, as if Candles had been in them, and the Sand was carried about in the Wind like Clouds. But to proceed: What was further observed by Mr. Clappham and others, who purposely ascended this Mountain: As soon as they were got a Mile in their Ascent upon the Pico, some of them grew faint and sick, several that ascended were taken with Fluxes and Vomitings, and were Aguish; their Horses, and even their Wine as well as themselves being extremely cold. When they had ascended a Mile further, they came to the black Rocks, from whence they travelled over a white Sand, so hot that it burned the Skin of a Dog's Feet who went up with Dr. Pugh. When they came to the Top, there were sulphureous Steams copiously ascending and continually, which were so hot, that they made their Faces sore, and at a little distance appeared like Smoak. There was little Alteration in the Wind, till we came to the Top, where it was very impetuous. The strong Waters there had lost their Force, but the Wine seemed rather more Spirituous. An account of the Pico. Upon the Top is a Pit called Caldera, of a Conical Figure, which is about 80 Yards deep, and a Musquet-shot over; It is covered over with lose Stones, Sulphur and Sand, which being stirred, very offensive Vapours are raised; it is dangerous to go further than 4 or 5 Yards into it, because their Feet are apt to slip from under them. In the Bottom is a sort of clearer Sulphur, which looks like Salt upon the Stones. From hence they could see the Grand Canaries, Palma and Gomera, and Hiero, 20 Leagues distant. When the Sun risen, the Shadow of the Mountain covered all betwixt it and the Horizon, so that the Top of it cast its shade into the Clouds; but when the Sun risen higher, so many Clouds were raised, that we could see nothing but the Emergent Tops of some Mountains, which to those that are below, sometimes seem to be wrapped about the Pico, and upon North-West Winds foretell a Storm. From the Tops of most of those Mountains very exuberant Spring's issue out in great Spouts. At the Foot of the Sugar-Loaf is a Cave about 10 Yards deep, and 15 broad, having a Hole at the Top 8 Yards over; opposite to which, in the Bottom, is a round Pit of Water 6 Fathom deep, whose Brink is about a Yard below the Surface of a Bed of Ice which encircles it, the Orifice of which is as broad as the Overture above, so that those that descend into it, are let down by a Rope, and swing to and fro, that they may light upon the Snow. The Water seems to be only melted Ice: From the Top of this Cave Iceicles hang very plentifully. The Perpendicular Height of the Pico is accounted two Miles and a half. Trees and Plants, etc. In all the Passage nothing but Pines grew; and amongst the white Sand, a bushy Broom; and where, in their Ascent they lay all Night, a sort of Cardon, whose Stems are Eight Foot high; the Trunk about half a Foot Thick, every Stem growing in four Squares, and rising from the Ground like Tuffs of Rushes; on the Edges of these grow several red Berries, which by squeezing, yield a poisonous Milk, which fetches the Hair off where it lights on the Skin of any Beast, so that I suppose it to be a kind of Euphorbium. In this Island there likewise grows a Shrub called Legnon-vell, which is carried to England as a Sweet-Wood. There are growing in this Island also, Apricocks, & Peaches, which bear twice a Year; very fruitful Pear-Trees; Almonds of a tender Shell, Palms, Plantanes, Oranges, Lemons, and especially Pregnadas, called so because each of them carries a small one in its Belly. Besides these, they have Sugarcanes, Cotton and Coloquintida, Carnations, and Roses that blow at Christmas; Sampire covers the Rocks, and Clover the Ground; and another Grass grows near the Sea, which is of a broader Leaf, and so luscious, that it will kill a Horse, tho' no other Cattle: 8 Ears of Wheat have been found to spring from one Root, and a Bushel to yield 130. The Canary Birds build in the Barrancos of Gills, Birds. which the Water hath fretted away in the Mountains, places very cold. They have also Quails and Partridges less than ours; great Wood Pigeons, Turtles at Spring, Crows; and sometimes the Falcon appears from the Coast of Barbary. They have Goats on the Mountains, Beasts, etc. and also Hogs and Coneys, but their Camels come from Lancerote. Amongst their Fish are the following, viz. The Cherna, Fish. a large well-tasted Fish. The Mero, Dolphin, Shark, Lobsters, Mussels, Periwinkles, and the Clacas, the best Fish in the World, which grow in the Rocks, 5 or 6 under a Shell, through the Top of which they peep with their Nebs. They have likewise a Fish with 7 Tails, each of which is a Span long united to a short Body, and much resembling our Eel. They have besides these, Turtles, and Cabridos, preferable before our Trout. The Island is full of Springs of pure Water like Milk, Springs. which in Laguna they strain through a Basin made of a Spongy Stone. Their Vines are very plentiful. Vines. Customs of the Inha●…ants. Dr. Pugh, who had done some charitable Cures amongst the Ancient Inhabitants, called Guanchios', was permitted to visit the Caves where the dead Bodies lie, which are sewed up in Goats Skins, very curiously and close, with Thongs of the same; which are more soft and pliable than our Kid's Skins: The Preserving of Bodies thus by Embalming them, was a Custom of a Particular Tribe of Men, who married only amongst themselves, and kept their Art of Embalming to themselves; so that, upon the Conquest of the Spaniards, most of them being destroyed, the Knowledge they retain of the Ingredients is by Tradition, which is that, Of the Embalming of Bodies. They boil in Butter of Goat's Milk, which for that Purpose is preserved in the Skins. 1st. A sort of Wild Lavender. 2ly, A Gummy Herb called Gara, which grows on the Mountains. 3ly, A kind of Showbread. 4ly, A Wild Sage, of which they make a Balsam, and when their Bodies are Embowelled, and several times washed in a Lixivium of the Bark of Pinetrees, and dried again either in the Sun in Summer, or in a Stove in Winter; they then several times successively anoint them with the Balsam, and dry them again, till they grow light, and the musculous Parts appear through the shrieveled Skin, and then they sew them up in Goats Skins curiously dressed; but the Poorer sort having their Brains taken out, are sewed up in Skins which have the Hair on. They have above 20 whole Families of their Kings and great Persons, which they will not discover. They are laid in several Postures; and some of them being laid along on Beds of Wood so hardened, that Iron will not cut them. They also have Earthen Pots so hardened, which they boil their Meat in; They make their Knives and Lancets of a kind of Slate called Tabona. Their Food. Their Food is Barley roasted and ground betwixt two Stones, which they make into Cakes with Milk and Honey, and carry it on their Backs in Goats Skins. They drink no Wine; nor do they care for Flesh; But are Lean, Tall, very Active and Courageous. They will leap from one Rock to another, Activity. sometimes Ten Fathom deep. Having a Lance which they point at the Place which they design to light on and then when they leap, they clap their Feet to the Lance, which Lance lighting on the Rock first, takes off the Violence of their Fall: Novices often break their Necks in learning. They whistle so loud, they may be heard 5 Miles; and it so affected the Relator's Ears, who was in Company with one of them, that he could not hear well of 15 Days after. Besides, they throw Stones with as much Force as a Bullet goes out of a Gun. But to return to Mount Teneriff, by one that went to the Top; it was observed, that no Snow was on the South side, and tho' it was on the North side, yet it was not within two Miles of the lowest part of the Sugar-Loaf. He likewise observed, that tho' the Sack which they drank at the Top was exceeding cold, and seemed to have no Effect on them; yet when they came into a thicker Air, two of the Company were drunk. Having tried to fire a Birding-Piece upon the Top of the Mountain, he could not; the Company that gave the former Relation, say they did. The sulphureous Matter they travelled over was so hot, that it burned two or three pair of Pumps in pieces in the Journey, tho' their Feet were not sensibly more hot than at other times. In some Regions of the same Mountains it was very hot, and on the other side of the same, very cold. Queries. To what Depth the Water will be frozen in hard Winters. To what Depth the Earth will be froze at the same time. Whether Muscovian Ice be harder than that in England. Whether Liquor cast up, will freeze before it comes to the Ground. Whether Brandy, Sack, etc. will freeze in Russia. Whether Instruments of Iron or Steel be britler there than here. Of the cracking of Timber and the Causes of it in Wooden Houses. Of the Preservation of Flesh, Fish, Herbs, etc. in hard Wether. Of the curing of those whose Nose or Cheeks, etc. are frozen. Of the Symptoms of those that are froze to death. Of the keeping of dead Bodies. TITTLE XX. Of the Air in Reference to Light, it's Perspicuity, Opacity, Reflections, Refractions, Colours, Light and Lightnings. Of the Air in reference to Light, ctc. I Am told by a Traveller, that on the Coast of Genova, from a high Place he could see Places remote, in a Morning, tho' not when the Sun was near the Meridian. The late King Charles the Second told me, that walking upon the Beack on the Strand by Dover, he unexpectedly discerned a Coast, which had rising and falling Ground, upon the Verge of the Horizon; and the same was observed by the Courtiers that stood by him; but in a little time it disappeared again, as if it had sunk into the Sea, which Phaenomenon I attributed to this, viz. That that Coast lying but a little too far off to be seen before, the Air interposed betwixt His Majesty's Eye and the Shoar, being filled with Vapours and subterraneal Steams, was rendered more refractive than before, by the help of which new Refraction, the French Coast which lay beyond it, was as if it were lifted up, in reference to the sight, and so became visible as long as that new Refraction lasted; but when those Steams were dissipated, they presently disappeared: In favour of which Conjecture I alleged, that a piece of Gold being laid in the Bottom of a Cup, and the Eye so placed, that the Object is but just hid from it, upon pouring in Water, the Object will, without removing the Eye, become visible. The Surface of the Water, which is a thicker Medium than the Air, refracting the Rays, and changing them from a Perpendicular to an inclined Position, so that they are caused to fall upon the Pupil. The Duke of York told me, that he was not a little surprised in Scotland, that contrary to the common Observation, by Country men in other Places, a Morning in which the Sky was red, was succeeded with a fair Day, it being usual in those Parts. It is observed, that when the Redness is pretty near the Ground, and appears with narrow streaks intensely red, it signifies bad Wether; but if it be elevated, and the Wind Easterly, it foretells a fair Day. Capt. James in his Northern Voyage observed, that by Reason of these Refractions, the Sun seemed to rise 20 Minutes too soon, and to set 20 Minutes too late; and this he learned by calculating of its rising and setting with good running Glasses, and comparing that Calculation with the Stars when come to their Meridian. March. This Evening the Moon risen in the Form of an oblong Oval along the Horizon. April. Tho' on a clear Sunshiny Day I could not see an Island which lies but 4. Leagues off Southsoutheast, yet when the Wether was misty, it might be seen from the lowest Place. The Height of it being taken Instrumentally, standing near the Seaside, it was 34 Minutes, the Sun b'ing 28 Degrees high, which shows how great the Refraction was; yet it will not be amiss to note here, that I have seen the Land elevated by Refractitious Air, when the Sun hath rose presently round. Jan. 6. The Latitude was 51, 52, which Difference was occasioned by a greater Refraction. Jan. 21. The Sun roof like an Oval, seeming as long again as it was broad, but as it risen higher, it gradually recovered its roundness. In Poland near Warsaw June, 1669/70 we had clear Wether, and extreme cold, and for two Days we observed the Sun and two Parhelions, from near 10 to almost 12 a Clock, yet the Air was free from Clouds, and so clear, that we could perceive Icy Spangles flying in it. And whereas usually in Frosty Wether, any smooth Iron or rather Metal, being brought into a warm Room out of the open Air, first a Dulness, and then drops of Water will appear in the Glass; at this time there appeared something like a hoar Frost. Whether subtle Particles of Cold will penetrate polished Metal or not, I will not determine, tho' the sudden Adhesion of ones wet Finger to Iron, seems to favour the Affirmative. The same Month returning back from Warsaw, I saw the Sun rife with a large Pillar, coloured like a Rainbow, perpendicular over it, out of a clear Horizon. In Cornwall it was observed, that in driving home Levels or Links, the Waters partaking of the Minerals, are sometimes sanative, and at other times cause Wounds. One who travelled over the Alps observed, that in the Clouds below, which seemed big with Thunder, something moved up and down like a shining Fish in muddy Water, the Lightning appearing through the Cloud. It hath been observed on the Coast at Naples, that in the Morning at Sun rising a Town which was at some distance off, seemed to have two Steeples, tho' it really had but one in it; and another Morning, the Refraction was so strong, that there seemed to be a very fair Town beyond it, walled about; and adorned with Towers and Steeples very delightful; which very Town disappeared when the Sun was risen higher above the Horizon. A dry blighting East Wind, which Country People call a red Wind, causes an Opacity or Thickness of the Air, like Vapours, which continuing for two Years together, not only blasted the Fruit, but the Leaves of the Trees just in the Tender. Mr. J. T. That the Air is sometimes Clear and Transparent, and sometimes darker and more clogged with terrestrial Steams, is a common Observation. But it hath been sometimes observed in Russia, that in a clear frosty Air, the Stars have appeared to be much more Numerous than at other times. Captain James hath observed, in Charlton Islands, which, tho' of the same Latitude with Cambridge almost, is but little warmer than Nova Zembla; that in January the Firmament appeared fuller of Stars by two Thirds than before; The Cloud in Cancer appearing full of Stars, and a great many small ones amongst the Pleyades: But the Moon rising about Ten a Clock, a quarter of them was not to be seen; the Wind for most part of the Month being Northerly and very cold: And the like hath been observed by the Russian Emperor's Physician. The Duke of York, when he was High Commissioner in Scotland, sent me word that he had observed the Sky so clear, that the Stars afforded Light enough to read by; and that several Fleaks of Light extended themselves from the Horizon, like so many Tails of Blazing Stars; and passing betwixt Charles' Wain and the North Star, seemed to terminate over our Heads: This was observed in December. TITLE XXI. Of the Operation of the Air on the Consistency of Animal Substances. The Effects of Air on Animal Substances. IT is generally believed by those, that judge of things by their Senses, that since the Air is an invisible Body, it acts only upon others, by its manifest Qualites, viz. Heat and Moisture: But I am apt to believe, that it hath other Faculties, amongst which, some may be called Generative and Restorative, and others Corruptive; and that not only in respect of Animals, and other Bodies of a slighter Texture, but also of Salts and Minerals. It hath been observed, that when Cheshire Cheeses have been carried from hence to the East-Indies, without being kept in leaden Boxes fitted to them; those that have been cut under the Line, were dry on the outside, but unctuous and soft in the Middle, as if all the oily Parts wanting in the outside, were shrunk back thither. But those that were cut when they had passed the Torrid Zone, and came into the Temperate Zone, were uniform and good enough. It is observed, that in Peru as well as Egypt, where it seldom reins, that Bodies are not subject to corrupt. In the Country last mentioned it is likewise observed, that the Air abounds with Nitre. It hath been observed, that under the Line, not only Biscuits have been altered, but that most of the Meat, and even Salt Meat hath been much impaired; but that their Water which was fresh, would be as clear and sweet as when first put into the Casks. Silk Stuffs that have been brought to Jamaica, I am told, have rotten without losing their Colour, by being exposed to the Air. TITLE XXII. Of the Operation of the Air on the Consistency of vegetable Substances. The Effects of the Air on consistent Bodies. A Piece of Limon having been kept a Year and some Months in a Receiver, with a mercurial Gage; it kept its Colour pretty well, as well as its shapes, except, that, the upper side was a little depressed, the Liquor which filled it up before stagnating upon a Glass Plate, which was adapted to the Receiver. When the Receiver was opened, the external Air rushed in with a considerable Noise; whence it was evident, that all the Air the Limon had yielded in that time, was not sufficient to fill the Cavity of the Receiver. Neither the Limon nor the Juice were mouldy or ill tasted; so that it made me think, that Mouldiness cannot be well produced without a Concurrence of the Air. The Liquor was acid, but clear and without Faeces, being of a Colour betwixt brown and red: It turned Syrup of Violets into a Purple Colour, and corroded Fragments of red Coral in the Cold. It hath been observed, that Lozenges, which a Scholar frequently carried in his Pockets, were dissolved when he came near the Line; but recovered their old Consistence, when much past it. TITLE XXIII. Of the Operation of the Air on consistent mineral Substances. The Effects of the Air on mineral Substances. IN drawing Copper out of deep Mines in Sweedland, I am informed, they use Ropes made of Leather, Links of Iron being subject to break with the Coldness of the Air and the Weight of the Ore. It hath been observed, that Glasses kept half a Year, tho' well nealed, have broke in pieces, and froze of themselves; the Cracks partly depending on some Particles of Salt, which had not undergone a sufficient Comminution. I am told, there is a House in Suffolk near the Sea, in which, tho' it is but 8 Years old, the Iron Bars are swelled, and so rotten that they'll crimble away; The Winds which blew upon those Windows in which they were being Southward; and I am likewise told, that Iron Bars drenched in Sea Water, and after exposed to the Air, were so far impaired, that when hammered, great Flakes would fly off them. Purbeck and Blechington-stone will moulder away in the Air; But those dug up at Painswick, near Gloucester, will, by being exposed to the Air, change their Primary Softness for a Crust-hard and Glassy Marble, which penetrates but a little way into its Substance, but is generated sooner, the oftener it is washed. TITLE XXIV. Of the Air in reference to Fire and Flame. Candle's which burn in Grooves furnished with Air Shafts, will sometimes continue burning 8 Fathom deep or more. When they come into close Ground, tho' Candles will burn for a while, yet when the Dust rises, they go out. Experiments touching the Relation betwixt Flame and Air. THE burning of Candles, etc. under a Glass Bell, as also Spirit of Wine, Matches, Touchwood, Sponck, etc. The keeping of Animals under a Glass Bell, whilst the Flame is burning. The burning of Bodies to Ashes in sealed Glasses, as also in exactly closed Receivers; Cotton burnt in a sealed Glass. The burning of a Mixture of Flames under Water in an E. R. as also of a saline Substance, and likewise of Salt Petre. A Pistol not firing in an E. R. An Experiment of burning Gunpowder. The burning of Spirit of Wine and Oil of Turpentine in Glass Vessels with slender Necks. TITLE XXV. Of the Air in reference to Fermentation. Of the Air in reference to Fermentation: RAisins being enclosed in an exhausted Bolt-head half full of Water, and set on a digestive Furnace, presently began to ferment; and swimming upon the Liquor afforded Bubbles, which were gradually fewer; and at last a Sediment appeared in the Bottom. The Top of the Bottle being accidentally broke, the External Air rushed in with some Noise, and the Surface of the Liquor was covered with Froth like Bottle Drink, and I thought I perceived a visible Fume come out of the Glass, which had a Languid Smell. The Liquor had a high Tincture of the Raisins, and was of a better Consistence than that of Water. TITLE XXVI. Of the Air as the Receptacle of Odours. TITLE XXVII. Of the Operation of the Air on the Odours of Animal Substances. Of the Effects of Air on Odours. SOur Grapes having lain 3 Years in Vacuo, were not mouldy; but the Surface of the uppermost was discoloured with a Tartarous Efflorescence. The Grains had a musty Smell; but the Liquor tasted Acid, and would corrode Coral in the Cold. The Gage scarce discovered any Air produced. In Madrid I am told, tho' they throw their Excrements into the Streets in the Night, yet the stink is not very much the next Day; nor will dead Animals stink long there. TITLE XXVIII. Of the Operation of the Air on the Odours of vegetable Substances. LArge Pieces of Oranges having been three Years included in Vacuo, their Rinds were, on their Surface, almost black; they yielded very little Liquor; being neither mouldy nor putrid. TITLE XXIX. Of the Operations of Air on the Odours of Mineral Substances. TITLE XXX. Of the Operation of Air on the Tastes of Animal Substances. MR. Nickson told me, that Meat might be preserved in frosty Wether, all Winter without Salt; but, if dressed when froze, would not relish well. TITLE XXXI. Of the Operation of Air on the Tastes of Vegetable Substances. TITLE XXXII. Of the Operation of the Air on the Tastes of Mineral Substances. TITLE XXXIII. Of the Operation of the Air on the Colours of Animal Substances. Of the Effects of Air on Colours. THE Air influences Colours so much on black Taffeta, that in Brasil, after it hath been worn a few days, it becomes of an Ironish Colour; but if it be kept from the Air, the Colour fades not. In a Particular Region in Brazil, 50 Leagues beyond Parigna, White People turn Tawny; but a little beyond that, they recover their Colour again. Upon Charlton Island, there is a sort of Birds called Partridges, which are white in the Winter, and grey in the Summer. TITLE XXXIV. Of the Operation of the Air on the Colours of Vegetable Substances. I Am told, that most Trees in Jamaica acquire a Greenness, when newly cut down, on that Part which is most exposed to the Air; and that Lignum Vitae, when green, is as soft as Oak. Several Trees which are soft when cut down, afterwards grow hard; especially the Cabbage-Tree, which presently hardens, and the Pith rotting out, it serves for a Pipe about 100 Foot long, which will not corrupt under Ground, but grows as hard as Iron. The Juice of Aloes Plants, which in the Island of St. Jago was clammy, bitter, and of a dark Colour; under the Line lost its Bitterness, and acquired a green Colour. Stains are most easily got out of Linen, at those times of the Year, when the Fruit with which they were stained flourish. TITLE XXXV. Of the Operation of the Air on Mineral Substances. ONE Part of Lapis Calaminaris being mixed with four of Salt-Petre, was kept some hours in a vehement Heat in a Crucible, by which means the Matter being alkalized, Water was poured upon it, which made a muddy red Tincture; which being set in a Wide-mouthed Glass in a Window, it became green and more diaphanous than before; but in a few Days, it became a transparent Liquor, a Powder subsiding which was red like Brick-dust. Spirit of Vinegar received no Tincture from Copper boiled in it; but being exposed to the Air in a broad Glass, in which part of the Filings were not covered with the Menstruum, some acquired a greenish blue Colour; but those Filings which were quite covered with the Menstruum, acquired no such Colour, till by evaporating it, they were exposed to the Air. A Solution of Sal Armoniac in Water, being poured on Filings of Copper, contained in a slender Viol, and on another parcel contained in a Wide-mouthed Glass, that in the latter was much more tinged than the other; And what was remarkable was, that tho' the lower Part of the Solution was of a deep Blue, yet it was covered with a Film of a differing Blue, like that of the finer sort of Turcoices. Three Drops of Spr. Sal Armon. being put upon two distinct parcels of Filings of Copper, which were on two pieces of brown Paper; one was exposed to the Air, and the other shut up in Vacuo; that in the open Air tinged the Paper with a Blue, the other remained ¼ of an hour without any Effect; but when it had been exposed to the Air as the other, it tinged it Blue. A yellow Urinous Spirit of the Lees of Wine, having Filings of Copper thrown into it, drew from them a pleasant green Tincture, which in a few days became yellow; but by being exposed to the Air, it turned green again; yet regained its Yellowness when it had been shut up for some time. I have sometimes observed, that tho' by being, kept from the Air, this Tincture would lose its Greenness, yet it would sometimes renew it again, without being exposed to the outward Air. Spirit of Amber extracted a green Colour from Filings of Copper. And tho' Spirit of Honey uses to turn Blue, when exposed to the Air, yet this Evening it continued yellow an hour. And I have observed, that tho' a Tincture often varied its Colour, being sometimes Colourless, and at other times of a deep Blue, yet another Bottle, which contained the same Mixture, did not so. It hath been observed about a Mountain in Wales, that there are several Stones, which tho' of a Rusty dark Colour, yet when exposed to the Air, in a few years they become white. Mercurius Sublimatus Dulcis and Vitriolum Romanum, being kept in Papers apart near two Years, the Sublimate looked like Antimony, and the Superficies of the Vitriol had acquired the same Colour. TITLE XXXVI. Of the Air destroying or introducing other less obvious Qualities into Animal Substances. TITLE XXXVII. Of the Air destroying or introducing other less obvious Qualities into Vegetable Substances. The Effects of the Air in producing Putrefaction. THE Heat and Moisture of the Air in Guinea, hath been observed so much to promote Putrefaction, that Maggots were found in white Sugar; several Drugs have lost their Virtues; and Ointments became verminous: And in the Island St. Jago, the sweet Meats contracted such a Moisture in one Night, that they were forced to dry them in the Sun. The Oxford Air being generally moist, agrees not with splenetic Bodies. Mr. J. T. Air too dry, tho' hot, produces not divers Infects, such as white Snails and Fleas, which are bred in wet Summers. TITLE XXXVIII. Of the Air destroying or introducing other less obvious Qualities into Mineral Substances. Less obvious Qualities introduced into Minerals. OBservandum etiam quod Antimonium Diaphoreticum quocunque modo, sive cum solo Nitro aut addito etiam Tartaro, paratum sit, tractu Temporis Aeri expositum, pravam ac quasi malignam induat Naturam, sumptumque intra, Cordis & angustias, Cardialgias, Lipothymias, vomitusque similia prava symptomata procreet, quae facile tamen evitabimus, si vel singulis diebus vel tribus Mensibus recenter illud conficiamus, vel jam paratum Antimonium Diaphoreticum vetustum, addita portiuncula Nitri, aut etiam absque Nitro per unam vel alteram horam, Vulcano tradamus penitusque igniamus, iterumque si Nitrum additum fuerit, edulcoremus, & parumper reverberemus. Zwelf. p. 800. The Earth of Egypt preserved dry, at the 17th of June gins to increase its Weight, which still increases more as the River augments. Ceruse of Antimony, I am told, as well as Ant. Diaphoret. acquired a vomitive Quality, though kept in a stopped Glass long. Those Pots which are made of Earth, which hath lain 4 or 5 Years dry, bear Fire best; and it is observed, that those Bricks which lie at the Tops of Brick-kills, bear Wether worst, being not so well burnt as the others. TITLE XXIX. Of the Air in reference to the Propagation and Vegetation of Plants. The Effects of the Air in respect of generation. IT hath been observed, that that side of the Pyrenean Mountains, which respects France, is flourishing and verdant, tho' at the same time, the other side which respects Spain, is barren, and looks dismally, being blasted and parched with noxious Winds. TITLE XL. Of the Effects of the Air in Reference to the Generation, Life and Health of Animals. The Effects of the Air in respect of Generation. DE vita igitur ac morte, & iis pene omnibus quae huic considerationi affinia sunt, dictum est. De sanitate verò morboque non solum Medici, sed & Physici est, causas quadantenus refer. Quatenus verò hi differant, & quatenus diversa contemplantur ignorare non convenit. Equidem quòd confinis sit quadantenus haec Medici Physicique Tractatio, & res ipsa testatur. Name & Medici, quicunque paulò elegantiores & diligentiores sunt, de natura dicunt, & artis sua principia inde sumere dignantur; & Physici omnes fere, qui concinnitatis aliquid habent, tractationem naturae usque ad medicinam persequuntur. Aristot. de Respirat. cap. 21. & parag. 87. The Temperature of the Air depends on subterraneal and terrestrial Steams mixed with the Air, and shuffled amongst one another. The last great Plague was foretold by one who had a great Swelling in his Groin the Year before, the like having happened to the same Man once before. That there are Changes in the Air which depend on the Motion of it barely, I am persuaded, not only because it ventilates those places it passes through when in Motion, and drives away stagnant Air; but I am told that in Languedoc, that if, when the Silkworms had eaten their fill, it happened to Thunder, the Air being put into a disturbed Motion, the weakest of them would die. Several Horses being let down a third part of the way into Mines 1000 Foot deep, some of them died; but others survived, and were there employed without any inconveniency to Respiration, tho' the Receptacles they wrought in were furnished with Air, only from the Groove by a moderately big Shaft: I am told, the deepest Mine in Bohemia is 2000 Foot deep. I am informed by one who lived at Tripoli and Guinea, that the Air is not constantly unhealthful there, but that the Men are sometimes suddenly taken with Fluxes and Fevers, which frequently kills in 48 hours. The Air in Russia in the Winter when the North Wind blows, is too thick for Respiration; And I am likewise informed, that when our Europaeans pass the Line, all the Lice about them ascend into their Heads, but disperse themselves again when they have passed the Equator a good way; but they usually die under the Equator. It it observed, that in Scotland Agues are very rare, tho' at the same time they are very rife in England. Aer autem corrigitur causa corruptionis ablata, & quod jam inductum est mali extinguendo; Roderici Fonf. de Sanit tuend. pag. 105, 106. si igitur ex nimio humore Aer putrescit, ignibus accensis qui omni putredini remedio sunt, exsiccandus, sic ignes, per vias & domus fiant ex odoratis plantis, qualis Laurus est, Mirtus, Pinus, Cupressus, Rosmarinus, & reliquae ejus generis, qua ratione pestem Athenis Hippocrates extinxit; vapores praeterea maligni per Aerem sparsi, dissipandi sunt, id quod à magnis ventis fieri solet. Sic Olysiponi, cum trium dierum ingens procella venisset pestis extincta nuper est; in Maroco ingens pestilentia vento quodam evanuit; qui veluti è furnace (adeo calidus erat) exire videbatur, Aerem autem nos imitando ventos commovere poterimus, si bombardarum strepitus fieri curemus; si verò vapores ex paludibus, ac stagnantibus aquis fieri videntur; eas resiccare aut novare oportet frequenter, maximè per aestatem. Renovantur autem novis supervenientibus aquis quas è fluminibus per canales traducere oportet; aut siccandae sunt factis rivulis, & fossis per quae superfluant ad flumina; quod cum primus magnus Etruriae Dux Cosmus Pisis fecisset, & magna animi contentione, tunc faciat Ferdinandus, factum est, ut saluberrimus ejus urbis Aer per omne anni tempus sit redditiis; verum si cadaverum inhumatorum multitudo Aerem inficit; magna & profunda facta fovea sepeliantur, si ab immundity, & excrementis, quae per urbem domos sparguntur, id quod, ut reor Bisantii, & Olysiponi, in causa ect, cur pestis adeo saeviat, ac duret, mundare oportet omnia; viae ac domus quotidiè, vel saltem semel in septimanâ repurgandae. 1. Joh. Beguinus in Tyrocin. Chimic. lib. 2. cap. 13. Dignum admiratione est, quod quamvis in viciniâ Hydriae Comitatûs Goriciensis, ubi reperitur copiose Mercurius, singulis ferè annis Lues pestifera grassatur, illa tamen semper immunis ab hac manere soleat, idque viri provectae aetatis se observasse, & à majoribus suis accepisse, mihi sanctè confirmarunt. Hinc patet, Mercurium esse summum omnis putredinis ac corruptionis alexipharmacum. 2 Michael Majerus in lusu de Mercurio. Argentum vivum est plurimorum morborum alexipharmacum, & ut testantur quidam, ipsius Pestis (cum eo loco ubi Mercurius effoditur, & tractatur, nunquam aut rarissimè hoc Contagium grassetur) dummodo maneat in suâ propriâ naturâ, & non à salibus aut aquis corrosivis inficiatur, ac venenosus reddatur. Several Clove Trees growing in the Island of Ternate, in the East-Indies, after they were all cut down, it was very unhealthful, the Exhalations from them being wanting to correct the noxious Steams of a neighbouring Vulcan. So that tho' the Inhabitants of Batavia formerly resorted thither for Health's sake, they now are some of them forced to go to supply the Deficiency of men, which the Unhealthiness of the Place makes, to supply their Garrisons. It is observed at Tangier, that new Comers are usually feverish for some time, especially if the East Wind blows. Several Aunts included in a Receiver, ran about till it was exhausted, and then lay as dead, but recovered when Air was let in again, two or three times successively. Relatione della Provincia di Malavar. pag. 64 & 65. Si Patrono quest barche dalla costa della pescaria, e vanno all isola di Ceilam, nella costa della quale per la lunghezza di venti miglia, tre sole miglias lontane da terra, set braccia abbasso arrivando sino alli dieci nel fondo, si ritrova infinita quanta di madreperle, escono per questa pesca le barche la matina col vento di terra, & arrivando all posto delle madreperle, gettare l'ancore, e fermaresi in quel posto, cominciano a tuftarsi nel mare i marinari, de quali ogni barca ne ha quindeci, e venti, e ciascuno di essisi lega nel mezzo, con una fuc, della quale ha cura uno, che resta in barca e con un' altra fune legandosi una pietra alla gamba, un' altro ha' pure cura di quella, e cingendosi un' sacco di cuoio dinanzi, mettendosi le guante alle many, cosi legato si tufta con violenza nel mare, lentando quelli le funi, e col peso della Pietra, va con grandiss' violenza giu, & arrivato ch' e, scioltasi dalla gamba quella fune, con la quale sta legata la pietra, resta egli libero, & la pietra viene subito tirata soprada quello, che n' ha' cura, et il marinaro poi comincia con molta sollecitudine à pigliare quelle madreperle, i li vengono dinanzi, e le met nel sacco, e sentendosi mancare la respiratione, tocca la fune, con la quale sta legato nel mezzo, e quello subito con grandiss' velocita lo tira et arrivando nella barca, scaricando le madre pearl ripiglia fiato, e dopo torna a legarsi di nuovo la pietra, e dinuovo si tufta come sopras ' e detto, e sempre cosi per tutta la giornata. Et è tanto faticosa questa pesca, eh ' essendo, tanto profunde le Madre perl nel mare, molti mancando loro la respiratione si trovano affogati. In the Island Johanna it is observed, that if a Stranger lies all Night there, he will die of a Putrid Fever in a few days; but tho' they go but a Mile upon the Sea every night in a Boat, they are generally safe. The Island is very hot in the Day, but cold after Sunset; and it is supposed, that the Unhealthfulness of the Place depends on Exhalations which plentifully arise from a vast Number of Plants that grow in the Island, which being condensed at Night, infect the Mass of Blood. There is one Hill in the Island very high, which is seldom ever free from Fogs or Clouds, which vary in their Height according as the Wether altars. On the Coast of Cormandel, and most Maritime Places of the East-Indies, there are sometimes such Fogs, that the Inhabitants for the time, are forced to keep the Windows and Doors of their Houses fast shut, there being at those times little or no commerce, tho' the Wether is very hot. At Balassore in the Bay of Bengale, and other Places of that Country, after great Raius the Air is so much corrupted, that the Smell is very nauseous to the Inhabitants, which may be occasioned by a great number of Frogs, left on dry places after Inundations, and putrified by the Heat of the Sun. At that time there is great Mortality amongst the Natives, chief by violent Fevers. When sick People are set on shore at St. Helena, they are generally much better in a few days, tho' before they were very weak. Le chemin plus court de Mosul a Bagdad, est par la Mesopotamie; mais on n'y trouve aucun Village, & le Samiel y regne tout l'Eté depuis Mosul jusques a Sourat; ce qui oblige a prendre l'eau, sur le Tigre où ce vent ne Soussle point. Le nom de ce vent et composé des mots, Sam et jel, c'est a dire poison et vent comme qui diroit vent de poison, Ce pourroit être le vent urens, dom parle Job xxvii. 21. Lorsque quelqu'un a respiré ce vent, il tombe mort subitement quoi qu' il en ait quelques uns qui ont le temps de dire qu' ils brûlent au dedans. D' abord qu' on est mort, on devient tout noir, et si on tyre le mort par le bras où par la jambe où par un autre endroit la chair quite les os et reste entre les mains de ceux qui la touchent. Thevenot dans le Bibliotheque Vniversel Tom. xiii. p. 266. Dr. Collins told me, that in Muscovy their Horses are subject to a very foul Disease, from which they defend them by keeping Goats in their Stables. The Plague generally at Smyrna, but especially Aleppo, at the End of June, or the beginning of July, degenerates into other Distempers, the infectious Particles of the Air, then being dissipated, and deprived of their pernicious Qualities. For a like Reason the Offensive Smoke of a Candle being further rarified by the Application of Smoke, loses its ill Scent and other ill Qualities; besides, it may be further offered, that the Heat of the Summer, may raise other saline Effluvia from the Earth, which mixing with the former, may correct and alter their infectious Qualities. And as for the Reason why the same does not happen at other places as well as Smyrna, it may be answered, that the Concurrence of Causes may be the Reason of the Difference, since some Soils may emit Pestilential Vapours with a sleight Heat, which others may correct when raised by a greater; for a like Reason to which, the Plague in Grand Cairo ceases, the Earth, upon the swelling of the River Nile, emitting Nitrous Vapours, which correct the Pestilential ones. To show, that the Qualities of the Air may be very much altered by the supervening Coldness or Heat of it, I shall allege the following Experiment, viz. That equal parts of Alum and Nitre, being dissolved in the same Portion of Water, when the Liquor was pretty well evaporated, and an earthen Vessel which contained it, was set in the Cold, the Alum was first coagulated into several octoedrical Grains, and upon a further Evaporation, at the last the Nitre shot into very fine little Crystals, of a Figure natural to such Salts. From whence we may conjecture, that several Salts which act jointly, may be so separated by supervening Qualities in the Air, as to act separately. A Mouse lived ten Minutes with a Quarter of Air, and three afterwards. TITLE XLI. Of Heavy Bodies sustained in, or taken up into the Air. TITLE XLII. Of Dew. TITLE XLIII. Of Rain. IT hath been observed, in the Country of Campen, that Rain falling into Pits, which were dug to a sort of Quicksand, would in a little time form a Clay, which skilfully handled, would yield good Iron. The Waters in that Country are obsered to leave a strong Matter at the Bottom when distilled, notwithstanding the Rectification. Quicquid erit, sine fuco significat, velut Rottenburg, L. 1. c. 8. De mont. Bohemtae, p. 26. A Milessow monte temporum praesagia capiuntur. Silesiae compastum appellant, perinde Milessow Temporum prognostes, jure merito dici potest. Vidi ex proximo totum aliquando Montem densissimis Nebulis contectum, eà prorsus Imagine, qua Mons Sinai Moyse in Nebula latente depingitur, at caeteri circum Montes, innubes & hilares velut rerum gerendarum ignari stabant. Sol ipse formosissimus ibat; at accolae locorum domum fugiebant, pecora urgebant, meque, ut domum protinus reciperem, properarem, & equos currum trahentes concitari juberem monebant, neque horae quadrans intercessit, jam Coelum obduci, Sol contegi, cripi omnis aspectus. Immensum Coelo ruit agmen aquarum — ruit arduus Aether, Virg. Et Pluvia ingenti sata letae, boumque Labores. Diluit, implentur fossae, & quae Divinus Poeta prosequitur. At contra etiam accidere vidi, ut caeteri fumárint Montes, Milessow nihil se commovente, nihil aut Nubilum, aut turbidum minanse; Incolae rogati, nihil esse magnopere timendum à caeteris spondebant, hunc unum intuendum esse, horum Nubila omnia à Milessow quodammodo devorari. TITLE XLIV. Of Hail. ON cerit de l'Isle en Flandres le 25 May; style nouveau, qu'il tombe dans cette ville la une graisle dout les moindres grains estoient comme des oeufs de Pigeon. Cet orage a passé sur la Citadelle & la ville, & na pas laissé une vitre entiere du coste du vent: les maisons sont toutes decouvertes, & les arbres rompus, les bleds coupez, & les perdrix & les lieures morts. On a pese plusieurs grains de cette graisle, dout les uns estoient d'un quarteron, de d emi liure, de trois quarterons, et les plus gros d'une liure & d'avantage. Il y en avoit un entr' autres qui avoit dans le milieu une espece de matiere brune qu'ou mit dans le feu, qui fit faire un grand bruit. Il y en avoit un, qui estoit diaphane, lequel estant mis aupres du feu, fondit tout aussi tost comme du plomb, quoy qu'il fut beaucoup plus dur que les autres. TITLE XLV. Of Snow. TITLE XLVI. Of other things falling out of Air. EO ipso anno quo Dux Eboracensis postremo rediit e Scotia Londinum, depluere tanta copia pisciculi halecibus colore, figurà, sapore quam simillimi in superiori Gallocidiae in Scötia parte non procul à mari, ut duo terrae jugera ad Robertum Murray de Brughton equitem pertinentia nunc Londini, ut audio, degentem, cooperuerint. Rem autem totam serenissimo Duci Eboracensi prius de eadem ab eo interrogatus, quod tum certior aliis de hâc pluvia factus esset, tanquam testis oculatus, ut qui aliquos horum pisciculorum videram, confirmavi: is porro ingeniosissime, summâque veri specie nodum ita solvit, ut diceret hos pisciculos unà cum aquis furentium ventorum gyro in turbinem actis evectos esse nubes, è quibus non procul inde pondere rursus suo relapsi fuerint in vicinam terram. TITLE XLVII. Promiscuous Experiments and Observations of the Air. TITLE XLVIII. Desiderata in the History of the Air, and Proposals towards supplying them. THE WORKS Of the HONOURABLE ROBERT BOIL Esq EPITOMISED. BOOK IU. CHAP. I. Experiments and Observations about the Mechanical Production of Tastes. THAT Taste, which is Quality of a Body, by which it is enabled to cause such a Sensation upon our Sensory, may be caused, by the Peculiar Size, Shape, Motion, and mechanical Texture of a Body will appear from the following Instances, whether they be simple or compound Bodies. EXPERIMENT I. To divide a Body almost Insipid, in two Bodies of very strong and very different Tastes Two Corrosives obtained from an insipid Body. Salted Petre refined, tho' almost an Insipid Body, distilled by the way of Inflammation, or by the Help and Addition of a Tasteless Clay, will yield a nitrous Spirit, so sharp and corrosive, that it will dissolve Metals; and a corrosive fixed Salt, different in Taste from the former, and this will dissolve Substances that the other will not work upon, and precipitate several Metals, and other Concretes, out of those Solutions, made of them by the Spirit. EXPERIMENT II. Of two Bodies, The one highly Acid and Corrosive, and the other Alkalizate and Fiery, to produce a Body almost insipid. An insipid Body produced from two Cirrosives. IF a sufficient Quantity of Spirit of Nitre, be dropped upon the fixed Nitre made per Deliquium till it is satiated, upon a gentle Evaporation, it will afford a Salt Petre; and I have often obtained the like from Spirit of Nitre and Salt Petre, which new Taste I am apt to believe proceeds from the new Figure and Size of the component Parts, which they acquire upon a mutual Attrition in the Preparation. For as the Prismatical Figure of Salt of Nitre, by being broke and rendered more minute, may have a more free Access to the Organ of Taste, and by its new figured Angles be able to corrode it; these again uniting and forming Prisms may become as inoffensive to the Taste as before. So Wedges may be made of a piece of Iron, and those again united after a convenient Manner, may form blunt pieces of Iron again, and tho' a Stick cut in two, be inoffensive enough to the Hand, yet if violently broken, the ragged Ends will be apt to prick into the Flesh. EXPERIMENT III. Of two Bodies, the one very bitter, and the other extremely salt, to make an insipid Substance. An Insipid obtained from a bitter and saline Body. IF strong Brine made of Salt and Water, be cast upon Crystals of Silver dissolved in Aq. Fort. or Spirit of Nitre, the dried Mixture being brought to Fusion in a Crucible, and kept in that state a competent time, will afford a tough Luna Cornea insipid, which will not easily dissolve in more powerful Menstruums than Spittle. PROPOSITION iv Of two Bodies, the one very sweet, and the other salter than Brine, to obtain an insipid Mixture. An Insipid obtained from a sweet and a salt Body. IF a just Proportion of Spirit Sal Armon. or Urine, be cautiously poured on a Solution of Minium in Vinegar or Saccharum Saturni dissolved in a proper Menstruum, if the Taste be not destroyed by the Mixture, it will by being dried and fluxed as in the foregoing Experiment. EXPERIMENT V Of an Insipid and Sour one, to make a Substance more bitter than Aloes. A Bitter obtained from an insipid and a sour Body. WHich is done by dissolving a sufficient Quantity of Silver in Aq. Fortis, to satiate the Menstruum; which if it be filtrated, and it's superfluous Moisture abstracted, it will yield Crystals more bitter; and no wonder, since if one touch the Powder of the Crystals with one's Finger or Nail, it would so slain them, that it cannot easily be removed. EXPERIMENT VI Of an insipid Body and a highly corrosive one, to make a Substance as sweet as Sugar. A sweet Body obtained from a corrosive and an insipid. IF good Aq. Fortis be put upon Minium, and kept together in a gentle Heat, till the Menstruum is satiated, it will be as sweet as Saccharum Saturni, but the Ingredients must be both good. EXPERIMENT VII. Of obtaining without Addition from the sweetest Bodies, Liquors corrosive enough to dissolve Bodies. A corrosive obtained from a sweet Body. SUgar distilled in a Retort, will yield a red Spirit, which being rectified, will come over clear and colourless; And the Caput mortuum will be altogether insipid; The Spirit is of a very penetrant Taste, and tho' taken to be a homogeneous Body, yet I have found it to consist of two Spirits, one of which would dissolve Copper; Yet these sour Spirits being incorporated with Minium, would acquire a saccharine Sweetness, part of which they will dissolve in Digestion. And a like Spirit to this may be obtained from Hony. EXPERIMENT VIII. To divide a Body, bitter in the highest Degree, into two Substances, the one extremely sour, and the other perfectly insipid. A sour and an insipid obtained from a bitter Substance. THis is done by distilling Crystals of Luna in a Retort, with a strong fire in a Sand Furnace; by this means the Spirits being driven away, unite into an Acid corrosive Menstruums, leaving an insipid Substance behind them. EXPERIMENT IX. To produce Variety of Tastes in one insipid Body, by associating it with divers Menstruums. Divers Tastes produced in an insipid. IF Zinke be dissolved in Aq. Fortis, Aq. Regis, Oil of Vitriol, Spirit of Nitre, Spirit of Salt, distilled Vinegar, Spirit of Sal Armon. or of Urine, it will, by a Conjunction with those sapid Bodies, so altar their Textures as to produce a different Alteration in the Tastes of each. EXPERIMENT X. To produce Variety of Tastes with one Memstruum, by associating it with insipid Bodies. Various Tastes caused by an insipid. AQua Fortis with refined Silver will produce a Bitter; with Lead, a saccharine sweet Taste; with Tin, a different Taste, tho' not odious; with Copper, an abominable Taste; with Mercury and Iron, bad Tastes of different kinds. It will likewise produce different Tastes with Tin, Glass, Antimony, Brass, Emery and Zinke. EXPERIMENT XI. Of two Liquors, the one highly corrosive, and the other very pungent and not pleasant, to compose a Body of a pleasant and Aromatic Taste. An Aromatic obtained from two corrosives. MIX gradually an Ounce of good Aq. Fortis or Spirit of Nitre, with an equal Quantity of inflammable Spirit of Wine; and when they are well mixed and grown cold again, if they be distilled over together, they yield an acid corrosive Spirit of a vinous Taste and a pleasing Smell. EXPERIMENT XII. To imitate by Art, and sometimes even in Minerals, the peculiar Tastes of natural Bodies, and even Vegetables. natural Tastes Artificially imitated. WHatever is the Plastic Agent in the formation of Bodies of each distinct Species, to show that the Nature of them depends on Mechanical Principles, I endeavoured to imitate natural Tastes Artificially. Endeavouring to alter the Taste, Smell, etc. of Oil of Vitriol and Spirit of Nitre, I obtained a Liquor, which tho' at the first pleasant, would at a certain point of time taste like Garlic. And it hath been observed, that Mustardseed put into Cider to give it a brisk Taste, made it stink like Garlic: And Semen Dauci fermented with Beer or Ale made it relish of Limon-Pills. If Gold be dissolved in a Mixture of Aqua Fortis and Spirit of Salt, and the Experiment be made hastily, one may obtain a Solution or a Salt of an Austeres Taste like Slows. And the like Taste I have observed in Gold volatilised; or dissolved without any Tincture at all. The last Instance I shall make use of, is this; Take a ʒj of Orris Root sliced, and infuse it in a Pint of Canary or Malaga Sack, till it hath given it the desired Taste and Smell, and then keep it in a cool place. The same Method being taken with Claret-Wine and Cochinele, the Tincture was taken for good Rasberry-Wine, some of which retained its Taste 2 or 3 Years. A short Excursion about some Changes of Tastes made by Maturation. Tastes produced by Maturation. THAT several Fruits after they are gathered, acquire a greater degree of Maturity, after they are separated from having any communion with the Soul of the Tree, is beyond doubt, since it is not only observed in England, that Apples, and Medlars become Mellow after they are gathered; but the Fruit called Bananas in the East-Indies, are gathered green, and hung up to acquire a greater degree of Maturity, and to ripen by degrees, and thereby undergo a Change both in Colour and Taste, and this I am told, hath been often found true in America. And that the Texture and Consistence of Fruits may be much altered and varied by the Influence of outward Agents, mechanically working upon them, is evident in Cherries, which undergo a sensible Alteration by a small Bruise, by which the Parts are forced to work one upon another; and another Instance we have in Wardens set to roast in the Ashes. And I have seen a sort of Pears betwixt France and Savoy, which being stewed a while in a moderate Heat, would be reduced to a juicy Substance of a lovely red Colour, and very sweet and luscious to the Taste; And some Pears by a moderate Compressure will lose their hardness, and acquire a yielding Contexture and a pleasant Taste. But not only vegetable, but more stubborn Salts may be altered by an intestine Motion of their own Parts, when dissolved in Water, so as to become of a peculiar and a pleasant Taste. And how in Vegetables, by an intestine Commotion of the saporifick Parts, a new Taste may be produced, is evident in Juice of Grapes, which from a sweet and spiritless Liquor, becomes a spirituous Wine, and after that a sharp Vinegar, without any Addition. CHAP. II. Experiments and Observations concerning the Mechanical Production of Odours. TO show that not only Tastes, but likewise Odours may be Mechanically produced, I shall lay down the following Experiments. EXPERIMENT I. With two Bodies, neither of them odorous, to produce immediately a strong urinous Smell. A Smell produced from inodorous Bodies. THis will succeed if good Quicklime and Sal Armoniac be ground together. EXPERIMENT II. By the bare Addition of common Water, to produce immediately a very strong Smell, in a Body that had no such before. A Smell renewed by an inodorous Body. IF a good Quantity of Camphire be dissolved in Oil of Vitriol, the Gum will lose its Scent, but by an Infusion of cold Water the Camphire will emerge and smell strong as before. EXPERIMENT III. Of producing some Odours, each of them quite different from that of any of the Ingredients. Odours produced different from those of the Ingredients. TWO parts of Oil of Turpentine being gradually mixed with one of Oil of Vitriol, the clear Liquor which they afforded, by Distillation in a sand Furnace, smelled very strong of Sulphur, and not of Turpentine. What remained behind in the Retort being forced, for the most part, over in the form partly of an Oil and partly of a Butter, they smelled like distilled Oil of Bees-Wax. EXPERIMENT. iv Of the Production of some Odours by local Motion. I Know several Bodies inodorous, which being considerably hot, emit not odorous Effluvia, yet being put into a peculiar kind of Agitation, emit a strong Smell. And some Woods yield a powerful Scent whilst in a Turner's Leath, which before were not odoriferous, as Lignum Vitae and Beech-Wood, the latter yielding a fragrant Smell much like Roses. EXPERIMENT V By mixing a good Proportion of a very strong scented Body, with an inodorous one, to deprive it speedily of all its umell. IF Aqua Fortis not too much dephlegmed, be poured upon Salt of Tartar till they cease to ferment; this Liquor evaporated, will yield Crystals like Salt Petre, but if distilled or burnt, they yield very offensive Fumes. EXPERIMENT VI By putting a very strong stinking Body to another of a Smell not sweet, to produce a Mixture of a pleasant and strongly Aromatic Odours. THis Phaenomenon is afforded by the Liquor prepared in the XI Experiment of the preceding Chapter. EXPERIMENT VII. By digesting two Bodies, neither of them well scented, to produce Bodies of a very subtle and strong fragrant Odour. SOme Ounces of Vitriol digested with ssj of Spanish Wine afforded this Phaenomenon. EXPERIMENT VIII. By the bare Addition of a Body almost inodorous, and not well scented, to give a pleasant and aromatic Smell to Spirit of Wine. EQual parts of Oil of Dantzick Vitriol and Inflammable Spirit of Wine, being digested together about a Month, and then being distilled, yielded a very fragrant Spirit, which was sometimes so subtle, that, tho' distilled with a gentle Heat in a tall Glass, it would fill the Elaboratory with Fumes; whence we may learn how much a Mineral Sulphur may be ennobled with a vegetable Sulphur; and how much new Coalitions and Contextures may alter the Odours of Bodies. EXPERIMENT IX. To make the forementioned fragrant Body, without Addition of fire, degenerate into the rank Smell of Garliek. A fragrant Body turned into one of a Garlic Smell. THE Odiferous Liquor mentioined in the preceding Experiment, being kept in a Bottle close stopped, in a little time acquired a Garlic Smell. And the like Smell I have perceived in an Oil distilled from vegetable and mineral Subtances. Salt of Tartar being digested with several times its Quantity of Onions, acquired a Garlic Smell. EXPEEIMENT X. With an inodorous Body, and another not well scented, to produce a Musky Smell. A Perfume made of an inodorous, and another Body not well scented. THIS we have done, by casting small Pearls into Spirit of Vitriol, for whilst the Menstruum was dissolving them, we could evidently perceive a strong Musky Smell. EXPERIMENT XI. With fixed Metals, and Bodies either inodorous or stinking, to produce strong and pleasant Smells, like those of some Vegetables and Minerals. To imitate vegetable Smells, etc. THO' Gold is inodorous, and Aqua Regis of an offensive strong Smell, yet the Solution being precipitated with Oil of Tartar, and the Precipitate fulminated per se in a Silver Vessel; we observed, that when the Fulmination was newly made, the Steams were of a very pleasant Smell, like Musk; so that Art, by lucky Contextures, may imitate natural and specific Odours: And not only so, but Nature may endue several differing Bodies with similar Smells; for in the West-Indies, there is a sort of Seed, which for its Smell is termed Musk-Seed; and in Muscovy the Skins of Musk-Rats, have such a kink of Smell; and Ducks at a certain Season of the Year, if violently chased, emit a Musk Scent. And on the other hand, there is a certain Wood in the East-Indies, which smells like Stercus Humanum. And I remember, that having distilled Saccharum Saturni with a strong Fire, besides the Empyreumatical Liquor, the Caput mortuum which was of a grayish Colour, emitted a pleasant Scent. And we may observe, that Nature sometimes takes the same way to produce different Effects; since tho' the Dung of most Animals is , yet that of a Musk Animal is well scented. So that it is enough to introduce into a Body noble Qualities, that it hath a due Contexture and Constitution of Parts. And on this Occasion, I shall add, that the Excrements of other Animals are sometimes so much varied by the Temper and Dispositions of our Constitutions, that Dung hath at a certain distance, smelled well, and like Musk to some People. And not to mention what hath been said of Alexander the Great, I knew a Gentleman, whose Sweat was very fragrant. And Civet, which is so well scented, in a lax Air, is as offensive to those that come too near great Quantities. And it hath been observed, that a Monkey upon eating Spiders, would cause a Scent like Musk. EXPERIMENT XII. To heighten good Smells by Composition. To enrich Smells by Composition. IT is observed, that a due Proportion of Civet or Musk mixed with Amber-grease, promotes the Scent of it; for it is not the Quantity, but the Justness of Proportion that inriches the Scent. The best Proportion being 8 parts of Amber-grease, two of Musk, and one of Civet. And it hath been observed, that Bodies inodorous mixed with the Ingredients of Perfumes, promoted their Scent; for which End, Wine Vinegar hath been made use of by some. And I myself prepared an Essence of Musk, by digesting some of it in Spirit of Wine for some Days, and then decanting the Tincture; and a weaker sort may be made, by pouring Milk upon the remaing part of the Musk, and decanting it after a cold Digestion. And one thing in this Tincture observable, is, that tho' it, of itself, hath but a weak Scent, yet if a few Drops of it be mixed with good Sack, it perfumes the whole very richly, both in Smell and Taste. CHAP. III. Many Changes of Colour produced by one simple Ingredient. Several changes of Colour produced by one simple Ingredient. TO make it appear how much the Colours of Bodies depend on the Variation of Texture, and their Modification, I tried the following Experiments; in which several Phaenomena are exhibited, by the Mixture of a colourless Ingredient, such as Spirit of Salt. I. If a little Spirit of Salt be mixed with Syrup of Violets upon a piece of Paper, it is presently turned from a Blue, to a red Colour inclining to a Purple. II. But if Spirit of Salt be dropped in a just Proportion into a Solution of Filings of Copper, made with Spirit of Sal Armoniac, the Blue will be turned into a green Colour. III. Having mixed Syrup of Violets with Spirit of Urine, Hartshorn or Oil of Tartar per Deliquium, and by that means turned it green, I mixed Spirit of Salt with it, which turned it red. iv If Spirit of Salt be dropped into Water, in which Red Rose Leaves well dried are put, it will make the Tincture to be of a lovely Red. V But if Tincture of Brasil be heightened by an addition of Spirit of Hartshorn, or Urine, Spirit of Salt will make it as pale as Sack; so that that which heightened the Red Tincture in the former Experiment, destroys it in this. VI Tho an Infusion of Lignum Nephriticum in Water, betwixt it and the Light appears yellow, yet when held so that the Eye may be placed betwixt it and the Window, it appears to be blue, yet upon the dropping of Spirit of Salt into it, it loses that property. VII. Having dropped Spirit of Salt upon Paper stained with Ink, the black was presently changed into a yellow and blue colour. VIII. If Filings of Steel be dissolved in Spirit of Salt, the filtrated Liquor will, upon Evaporation, shoot into green Cristals; which, if when they are dry they be kept in a Crucible, a moderate Heat will turn them red. IX. We found that the red Precipitate of Mercury per se would dissolve in Spirit of Salt, though crude Mercury will not; we likewise found, that the Redness of Minium was wholly destroyed by boiling it in Spirit of Salt, and that the Tincture of Coral extracted with this Menstruum, was wholly void of colour. X. If Filings of Copper be long digested in a Sand-Furnace, in a good quantity of Spirit of Salt, viz. as much as will cover it the breadth of two Fingers, the Metal being in part dissolved, will be of a colour not unlike a muddy Red, if held betwixt your Eye and the the light. XI. But if it stand some hours in a wide-mouthed glass, it will be of a green colour, finer than that which is made by a solution of Mars. XII. If Spirit of Salt be dropped into a Solution of Silver, or Quicksilver in Aqua Fortis, the mixture will be of a milky whiteness, and presently deposit a white Precipitate. XIII. And the same Phaenomena will likewise happen, if Spirit of Salt be dropped upon a Tincture of Benjamin, or a Solution of Resinous Jalap. XIV. Having mixed a sweet Solution of Red Lead in Spirit of Vinegar, with a Tincture of Red Roses, I dropped Spirit of Salt into the mixture, which precipitated the red, and turned the green mixture into a durable Scarlet, which if disturbed by a mixture of the white precipitate, will be of a Carnation colour. XV. Spirit of Salt, which was muddy by standing upon Filings of Copper, being boiled to a clearness, and set in a wide-mouthed Crystal Glass, in a small time puts on the colour of a Germane Amethyst; and, in three hours' time, a lovely Green. XVI. Having gathered by filtration the Precipitate of Sublimate dissolved in water, and when it was dry, poured Spirit of Salt upon it, in a glass Vessel, the precipitate at the first will become white, and when the ebullition which succeeds the mixture is ended, it becomes a transparent Liquor. XVII. Having dropped Spirit of Salt upon a fourth part of Calcined Copper, we found that the mixture produced a Tincture of a muddy Red, and a white Powder, which being acted on by the fire, exhibited several colours. XVIII. The Solution of Copper, just now mentioned, being put into a Cylindrical Vial, and 2 or 3 Spoonfuls of highly rectified Spirit of Wine poured upon it, by shaking the mixture we obtained a Liquor of a green Colour like that of Emeralds. XIX. A few drops of Spirit of Wine being dropped upon a Taffeta Ribbon, changed its Green into a Blue Colour; and being dropped on a black Ribbon, altered that, and made it put on that which is called a Fading Leaf. XX. If Spirit of Salt be dropped upon Purple Paper, it presently turns it Red. XXI. Powder of Antimony being boiled to a Dissolution in Spirit of Salt, in a glass Vessel, lost its blackness, and the Solution being dropped into Water, it in a little time subsided in the Form of a white Precipitate. These Experiments being laid down, it may be necessary for us to observe, how unexpected the Result of most Mixtures are; which may be an Argument against the too frequent use of Compound Prescriptions, since it often not only is uncertain how those Ingredients may destroy the Virtues of each other, but sometimes whether they will duly mix according to Physician's expectation. CHAP. IU. An Experimental History of COLOURS begun. Containing Part the First. THOUGH there are some, especially Chemists, who think that a considerable Diversity of Colours, Diversity of Colour not always an Argument of a variety in Qualities. must always employ a Diversity of Nature; yet we see, that Taffetas are endued with changeable Colours, as well as the Feathers of several Birds, which have as great an Affinity in Nature as in Place; and not only several Feathers vary in Colour from one another, but sometimes several parts of the same Feather: And there is no less variety of Colour in several Leaves of Flowers, though no difference can be discovered in their Properties: A considerable Instance in which, we have in Marvel of Peru, which though it produces several Scores of Flowers in its Season, yet I have scarce found two coloured alike. Yet changes of Colour oft signify Alteration in the Properties of Bodies. But though I believe that a variety of Colours does not always imply a Diversity of Properties, yet I question not, but that an alteration, in point of Colour, signifies a Variation in the Disposition of Parts of Bodies; which is evident in the Extraction of Tinctures, and several other Chemical Operations, wherein the Change of Colours is the only Observation by which the Artist regulates his Process. So we see, that several Degrees of Maturation produces various Colours in Fruit; and Steel, if it be heated glowing hot in the fire, and held over a Basion of Water, till it changes its white to a red Colour, so far as is then quenched will be hardened, and when polished at the end, will look whitish; but if the end of the Steel be held in a Candle, so that the polished part may not be sullied, that which is almost contiguous to the Candle, would change from a bright Yellow to a deep one, or a sanguine Blue, and from that to a fainter, and then to a deeper Blue; and in each of these diffetent Appearances, its Texture is so much different, that if whilst it is yellow it be cooled, it is fit for Gravers Drills, but when blue, it is softer and fit for Springs of Watches; and if it be kept long in the flame after this blue appears, it will be too soft for Drills till hardened again. And it is not a little pleasant to see how these Colours will succeed one another and run along the Steel very fast. But because the flame of a Candle usually sullies the Steel, we generally make use of a red-hot Iron to heat it with. But not to prosecute these Experiments out of their due Place, before I descend more Particularly to present you with my Considerations concerning Colours, What is meant by Colour. I think it requisite to premise, That Colour being a Word of a twofold Signification, in the following Discourse, I shall sometimes use it to signify only the Sensation of those reflected and modified Rays of Light, which cause that Effect on the Sensory; and generally, in the vulgar Acceptation, intimating by it, the Disposition in the Object which causes the Rays of Light to be reflected, so as to produce on the Sensory this or that Colour. What the Perception of Colours depends upon. And, perhaps, it may not be inconvenient to add, that it is the Opinion of several Modern Atomists, that the Sensation of Colours depends not so much on the inherent Qualities of the Object in the Sense, but that such a Motion is given to the Spirits in the Retina, that that communicated to the Brain, and causing a Local Motion in some part of it, we always think we see such a colour, when the slender strings of the Retina are put into a like Motion, whether the Light concurs to the Production of that Motion or not; whence dreaming Men often think they see several things in their sleep; and distracted Persons fancy they see several things before them, which depends only upon an Internal Local Motion of their Spirits: And so upon a violent blow upon the Eye, we sometimes fancy we see Lightning and flashes of Fire; and even upon a blow on the Head, or when internal Humours cause such a Concussion in the extremities of the Optic Nerves, as is wont to produce a Sensation of Light. And I remember, that having myself a violent Cough, I fancied I saw flashes of Light, which presently disappeared again: and a very discreet Lady observed, that the day before she was seized with some violent Hysterick and Hypochondriacal Fits, which for the time gave her a bastard Palsy, every thing before her seemed to be died with bright and vivid, but unusual colours: And I am told by an ingenious Gentleman, that several that were seized with the Plague, sometime before, fancied every thing coloured over very beautifully; and this Symptom was successfully removed, as well as the other Symptoms of that Distemper by a Vomit The Vomit which was successfully given in this was made of about 8 or 10 Drachms of Crocus Metallorum, and half a Drachm of white Vitriol. But further, as the Apparition of a Colour may be caused by the Motion of the Humours within, so the Sensory being Indisposed, that Indisposition may vary the appearance of External Objects: For I have taken notice, that after looking upon the Sun or Moon with a Telescope, my Eye hath been so altered, that the flame of a Candle seemed to vary much in its colour from what it used to be, and if I often opened and shut my Eye whilst that adventitious Colour seemed to last, I could discern it gradually diminish, till the Candle appeared to me as before; and one thing worthy of notice was, that if I looked upon the Object with one Eye, when the dazzled Eye was shut, the Adventitious Colour disappeared, but was visible again, upon opening the dazzled Eye. To this Observation I shall add, that a Lady, who had by a Fall, got a Hurt near her Eye, for six Weeks together fancied every thing covered over with very dazzling and glorious Colours, especially white Bodies, some of which were such as she could not describe. And a Learned Gentleman told me, that looking upon the Sun with a good Telescope, without a coloured Glass to guard his Sight, the Brightness of the Object left such an Indisposition in his Eye, that nine or ten Years after, whenever he looked upon the Window, he fancied he saw a light Body before his Eye, of the Size and Brightness of the Sun, as it appeared to him in the Telescope; to which Instances, I could add others from the Experienced Epiphanius Ferdinandus, of the Symptoms of those Bitten by a Tarantula; from whence it would appear, that an Indisposition in the Organ of Vision, is sufficient to vary our Judgement of Colours, but these may be more properly delivered in another place. The Superficies of a Body considered as the cause of Colours. But to proceed, from what hath been said it appears, I allow and teach, that the superficial Parts of a Body, reflecting the Rays of Light, and modifying them, may in one sense be said to be the Cause of that Colour it represents, since as the Beams of Light are variously modified, we perceive several Sensations. And tho' some hold, that the Rays of Light which convey Colours, are not reflected barely from the Superficies of a Body, but penetrate deeper into its Substance; yet we are apt to call those Bodies transparent or semidiaphonous, whose Substance the Rays of Light visibly insinuate themselves into: And that in all Bodies there is no such Penetration of Light is evident, since several Substances appear to be of one Colour on the outside, and of another within; which is evident not only in Fruit, but tempered Steel; for tho' it be furnished with very vivid Colours on the Superficies, yet within a Hairs breadth of it, it retains its Steel Colour: And a more Eminent Instance is, that Led being melted and poured into an Iron Vessel, when the Scum was taken off, several Colours succeeded one another, upon its Superficies, and that which appeared last, before the Metal cooled, remaining upon the Superficies of it, we found, that if never so little was taken off, that adventitious Colour would be taken off too, and the Metal would appear in its own Colour; which shows not only what I alleged it for; but also, that probably an adventitious Colour may be acquired by the Effects the saline Parts of the Air, have on Led so disposed to receive its Impressions, which it will not do, till brought to a much higher degree of Fusion than bore melting. One thing remarkable in these Colours was, that they succeed not so regularly as those in Steel, but in the following order, Viz. Blue, Yellow, Purple, Blue; Green, Purple Blue, Yellow, Red; Purple, Blue, Yellow and Blue; Yellow, Blue, Purple, Green mixed, Yellow; Red, Blue, Green, Yellow, Red, Purple, Green. Tho' it is held by ancient Atomists, that the Figure of a Body is sufficient to vary its Colour; yet I am persuaded, that there are other things requisite; since we see by the help of good Telescopes, that the Superficies of Bodies are not only full of several Protuberances, but likewise several Cavities, which appear not to the naked Eye; so that the very Figures of those may have a great stroke in causing various Colours, and differently forming the Superficies of a Body, so as to enable it variously to reflect the Rays of Light, and cause different Effects in our Organ of Sense. The various Figures of the Superficial Parts requisite for the Production of Colours. But besides the various Figures of these superficial Particles, the Surface of a Body may be enabled variously to reflect the Rays of Light, as they are bigger or less; and the Protuberant Particles are set closer, or at a greater distance: So Water if it have but a few Bubbles on the Top of it, hath scarce any sensible Colour, but if it be beaten into a Froth, and a great number of Bubbles are close set, it presently varies its Colour, and seems white; to which not only the Number, but the Convex Superficies of the Bubbles conduce; nor is it requisite, that all the Protuberant Corpuscles should be of one Figure, since, those which produce a Blue, and those that yield a Yellow being mixed together, afford a green Colour. But further, the Cavities intercepted betwixt the Protuberant Parts and their Figures, are to be considered in the Production of Colours, as well as the Figure and Size of the Particles themselves: For the Superficies of a Body may be cut transversly with a Methamatical Plain, void of Depth or Thickness, above which as well as below, may be several Superficies, as in the Superficies of the Earth, there may be several Parts above the Horizontal Plain as well as below; upon which Account, the Rays of Light may be so differently reflected, as to cause different Colours; so the two sides of a Piece of red Glass seem differently coloured, when the one is Rough, and the other Polished; and tho' several sorts of Marbles are never so curiously Polished, yet their Superficies so far vary, as to exhibit distinct Colours. The Situation of them likewise requisite. Besides, in variously reflecting the Rays of Light, the Situation of the superficial Parts of a Body are considerable, in reference to the Light and the Position of the Eye, and also their order in reference to each other; for the Rays of Light will be differently reflected to the Eye, from Parts which are erected upon a superficial Plain, from what it will be from those Parts inclined and obverted to the Eye; so Plush or Velvet varies its Colour as the Parts of it are differently inclined; and a Field of Corn varies its Colour as the Wind depresses the Ears of Corn successively, or in different places: And for a like Reason the Hair of a Dog exhibits a different Colour, when the order of them is changed; and so the Parts of Water in Froth, and the Parts of Hartshorn shaved, altar their Colours, and Glass by being beaten, loses its Transparency with the order of its Parts, and becomes white; And for a Reason not very different, I have observed, that Pease set in parallel Lines, when they are risen about half a quarter above the Ground, by casting one Eye the same way with the parallel Lines, the Ground would appear of its own dirty Colour, but if I looked upon it transversly, it would wholly appear green, the Rays which were reflected from the Soil being intercepted. The Motion of the part of a Body contribute to the Colour. And that the motion of the Parts of a Liquor, may contribute to the change of a Colour, I am persuaded, since I have elsewhere mentioned a Liquor, which, whilst it was at rest, would be clear and transparent, but when its Parts were put into Motion, they would rise up and form a white Fume; and the like Fumes I have observed to rise from a Liquor diaphanous, and another red. And if the Superficies of a Body be made up of Parts, whose different sides afford several Colours, than the Motion or Rest of that Body may contribute to the variation or continuance of a Colour, since a new side being turned towards the Eye, we must consequently see a new Colour; so when the Leaves of a Tree, whose Colour on each side varies, are forced by the Wind, to appear with their other sides outward, they exhibit a new Colour, tho' a few of them makes no considerable Alteration; as a single Thread of Scarlet, seems almost void of Redness; but when several of them are placed together, their Colour becomes more conspicuous. So likewise in a Piece of Taffeta which is made of red and blue Threads interwoven, I found by a Microscope, that when the Silk was so commodiously placed, that the blue Threads were not intercepted by the red ones, the Colour would be blue; but when the red Threads were more commodiously placed than the others, the Colour would vary: Wherefore it would not be amiss to endeavour to discover a Reason, by the Use of Microscopes, why Mother of Pearl, Opals and such like Bodies are of such curious Colours, and what contexture of Parts is apt to produce Colours so delightful. How far Asperity contributes to Colours. But till we are furnished with better Microscopes, or more exquisite Senses, I fear these things must be undiscovered, since there are several degrees of Asperity, and the Parts which form them are so minute, that we are not able to know how their Shades are mixed with, or intercepted one by another; tho' I was told by Dr. Finch, that there was a Blind Man at Mastricht, not far from utretcht, who was able to distinguish simple Colours by the Touch, tho' mixed Colours he could not discern: And The Account this Man gave the Doctor of his Sensations of those Colours was, that Black and White were the most Asperous Colours, and so like, that it was hard to distinguish them; but Black was the rougher of the two; Green next to it, Grace next to Green, Yellow a degree below that, Red and Blue so much alike, that they were hard to be distinguished, but that Blue was the least rough of the two; and these Diversities of Surfaces this Man discovered, by placing the Body whose Colours he was to try betwixt his Thumb and his Forefinger; And it was very remarkable, that his Thumb was not only the most sensible of the two, but that he had only this Exquisiteness of Sense when fasting, the least drink disabling him, to distinguish so nicely the difference of Colours. But I am apt to suspect, that this blind Man rather discriminated these different Colours by the Smell of the ingredients, than the Touch; and that if the Organ of Touch contributed to it, it rather did it, by discovering the several Forms than Degrees of Asperity, since he found it so difficult to distinguish Black and White from one another, tho' not from other Colours; and indeed tho' the Ribbons which were offered might be almost equally rough, yet in such slender Corpuscles as those which reflect the Rays of Light, we may easily conceive, not only a greater closeness of Parts, or a paucity of extant Parts, but that they may be otherwise ranged, and the Cavities left betwixt, much deeper in one than the other; for supposing the Protuberant Particles to be very slender, and cylindrical like the Hair of a Brush, and furnished with Hemispherical Tops, they may be so very sharp, that a less exquisite Touch, cannot distinguish them, than that of this blind Man. Nor is every kind of Roughness inconsistent with Whiteness since the level Superficies of Water being made rough by Bubbles, presently acquires a Whiteness, and so does Glass when scratched with a Diamond. But to proceed, supposing the sharp pointed Particles which are ranged upon the Superficies of black and white Bodies were so like, that the Touch could not distinguish them easily; yet upon the Account of some difference in the Cavities, which intercept the Rays of Light, they may variously reflect it; as if the Cavities of a black Body be deep, and the other superficial, the one will drown and detain the Rays of Light, whilst the others undisturbedly reflect them. From whence it appears, that Colours rather depend on different Forms of Asperities, than on different degrees of it; and tho' the blind Man tells us, that Black was the roughest of Colours, yet it does not therefore follow, that those Bodies which have the least Asperities, must be the lightest, and reflect the Rays of Light most, since according to him, White is the roughest next to Black; and tho' he assigns Yellow two degrees less of Asperity than Green, and as many more than Blue, yet it is manifestly to the Eye a lighter Colour, and reflects the Rays of Light more plentifully than either. How many ways Liquors may alter Colours. But to return to what I was saying of the different Asperities of Bodies, by which Colours may be diversified: To assist us to judge of the Reason of the Changes in Colours produced by corrosive saline Corpuscles in a fluid Form, I shall consider how many ways such Liquors may, by working upon them, altar the Superficies of Bodies upon which they act, and consequently cause them variously to reflect the Rays of Light. And First, Such Liquors may alter the Colours of Bodies, by insinuating and lodging their small Particles in the Pores of a Body: So Oil or Water dropped upon Paper, altars the Colour of it; and the High Road upon Rain loses its dry Colour, and changes it for another. Secondly, A Liquor may alter the Colour of a Body, by freeing it from an adventitious Colour; as when the dirty Colour of Gold is taken off by putting it into the fire or Aq. Fortis. And not only Silver may be restored by the like means to its genuine Lustre, but I know a volatile Liquor, which, incorporating with Grease, will take such Stains out of . And I have tried, that having rubbed a Compound Metalline Body on a Touchstone, Aq. Fortis would take off all the other Ingredients, and leave the Gold, appearing with its genuine Colour. Thirdly, A Liquor may alter the Colour of a Body, either by destroying or subdividing the Parts of it; as when Wood is cut into Chips, or a piece of hot Crystal quenched in cold Water, for it being by that means cracked, will not reflect the Rays of Light as before. Fourthly, A Liquor may change the Colour of another Body, by collecting together Parts of Matter scattered and dispersed; so Quicksilver poured into a Solution of Gold, acquires a thin Film, of a yellow golden Colour; and by a like Method all those Colours, that seem to be produced by Precipitation, are generated; tho' Resinous Gums dissolved in Spirit of Wine being unites into a Mass again; and so rectify●d transparent Butter of Antimony, upon a Mixture of Water precipitates that white Substance, which when its Salts are washed off, is called Mercurius Vitae. A Fifth way, by which a Liquor may alter the Colour of another Body, is, by altering the Texture of its Parts, as, when Quicksilver is kept long in a convenient Heat; Metals are corroded, or Fruit is bruised; or when the Parts of a Liquor are agitated by the Affusion of another Body; or when Chemical Oils are shaken in a Bottle; for the Bubbles by that means raised will exhibit very lively Colours. Another way, is, by putting the Parts of a Body into Motion, after which they may unite in a new Form; so Vitriol rubbed upon the Blade of a Knife, imparts not any new Colour to it; but if the Vitriol be moistened, it will impart a true Copper Colour to the Iron. Another way by which a new Colour may be imparted to a Liquor, is, by an Association of its saline Parts with those of the Body it is made use of to work upon, by which means the superficial Parts of a Body, may be altered both in Shape and Figure; and not only a greater number or a less, may be comprised in the same space, but the Pores betwixt the Protuberant Parts may be much straitened, and the old ones partly filled up, as well as new ones intercepted; as when Quicksilver is dissolved in Aq. Fortis, the saline Parts of the Menstruum associating themselves with the Mercurial Corpuscles, will afford a Green, which afterwards degenerates easily. And so Minium by being dissolved in Spirit of Vinegar, yields a clear Solution; and if Aqua Fortis be dropped upon a Copper Plate, the Parts of the Metal being corroded, acquire an Asperity, and coagulating with the Menstruum form Grains of blue Vitriol, whereas Spirit of Urine will produce a much deeper Blue. And Aqua Fortis, which will give Red Led a dark Colour, with crude Lead will produce a white one, with Iron, a reddish, and upon white Quills a yellowish Colour. And that in Chemical Dissolutions and Precipitations the saline Parts of the Body made use of to precipitate, unite with metalline Parts they precipitate, we shall have reason to believe if we consider how much Vitriol, and the Calces of Metals are heavier than the Metals themselves. After what we have laid down concerning the Causes of Changes of Colours, there are two things to be taken Notice of; The one is, that there are other ways to vary Colours speedily, besides those we have taken notice of by the help of Liquors; as in Tempering Steel, etc. The second Particular requisite to be noted is, that tho' a Change of Colour may be effected any one of the ways abovementioned, yet generally at least three of them are at once concerned. Several Bodies generally esteemed opacous semidiaphanous. From what we have been discoursing of the Asperities of Bodies in causing a Reflection of the Rays of Light, one would think that the Substances themselves are perfectly opacous and impenetrable by the Rays of Light, and so contribute to the Variety of Colours, reflected to the Eye: But I am apt to believe, that even those Bodies which we call Insensible, are compounded of Parts still more minute, whose Commissures are not utterly impervious to the Rays of Light, and that the Bodies compounded of those are in some degree Diaphanous. For in a dark Room, where the Light is only permitted to enter at one Hole, I have observed, that those Motes which were otherwise insensible; in the Beams of Light, would represent several vivid and florid Colours, like those of a Rainbow, or of sparkling Fragments of Diamonds; and as soon as that Position, which they had at that time, in reference to the Eye and the Light, was lost, they ceased to represent those Colours, tho' still remained visible; so that from hence it appeared, that these small Fragments of Matter, commonly reputed Opacous, did not barely reflect, but also refracted the Rays of Light: And it is not a Phaenomenon altogether to be slighted, that Water, tho' a diaphanous Body, hath a manifest Power in refracting the Rays of Light so, that by passing through it, they represent the lively Colours of a Rainbow. And it is further observable, that several Bodies which are generally esteemed Opacous, appear in a great measure transparent, when they are reduced into thin Parts, and interposed betwixt the Eye and a Powerful Light, which is evident in thin Plates of Ivory, thick Leaves of Trees, Shells of Fishes and shave of Wood And in a darkened Room I found, that the Substance of my Hand was in a great measure transparent, when it was held betwixt my Eyes and the Rays of Light which came in at a small Hole. And not only white Marble of a convenient Thickness, but Lapis Specularis, or Muscovite Glass, being divided into thin Plates, will be considerably transparent; and even Coral itself will manifest the same Transparency if held near the Light. But on the other hand, I must own, that having looked upon Mercury precipitate per se, Filings of Copper and Steel, the Red Calx of Lead, and the Red Colour of Vitriol, they appeared not to have the least Transparency. How far the Transparency or Semidiaphaneity of Bodies may contribute to the Variety of Colours produced by them, I shall not take upon me to determine, since beaten Glass, Snow and Ice, whose superficial Parts are manifestly transparent, represent not the lively Colours which they do when conveniently qualified by their Bigness, Shape and Texture. But to draw an Inference from what hath been said of the Cause of Colours; It appears, that according to the Hypothesis we have laid down, Bodies can only be said to be coloured when placed in the Light; but that, according to the Ancients, if we take the Sense of the Word Colour, to mean only that Disposition of the superficial Surface of a Body, which enables it to modify the Rays of Light; They may be said to have Colours in the Dark, since they have that Disposition, which enables them to reflect the Rays of Light in such a Form as to produce Colours. The short duration of Colours no Argument of their not being genuine. And from what hath been delivered, it likewise appears, that tho' Colours which are evanid, and last but for a while, as the Colours of the Rainbow, and all Emphatical Colours, are generally distinguished from True and Genuine ones, in as much as the latter are produced by Reflection, and these proceed from Refraction; yet, since we usually account all Echoes genuine Sounds, and all Smells true Smells, in as much as they are real Objects of the respective Sensories they affect, by the same Reason we may conclude these Emphatical Colours genuine, since the Rays of Light equally affect our Sensory for the time: And tho' the shortness of their Continuance hath been offered as an Argument of their not being genuine, by the same Rule we might say, that the Colour of Grass is not genuine, because the Colour of an Emerald is more lasting; but white Colour of Froth is held to be genuine, tho' it is soon generated, and in a little time destroyed. Besides, were the Whiteness of Froth accounted an imaginary Colour, we must no longer believe such to be distinguished from genuine ones, by Refraction; since Froth retains its Whiteness, whether the Sun be setting, rising, or at the Meridian; the Position of the Sun in reference to the Eye, and the Object not at all diversifying it. Moreover, were a Colour to be pronounced genuine by the time of its Duration, the white Froth of a Tenacious Body, might be said to be more genuine, because it will continue much longer, than the Colour of those Flowers of the Marvel of Peru, which fade the very day they are Blown: And I have seen a Virginian Flower, which seldom continues longer than a day. And that the bare Disposition of the Parts of a Body, by which it is said to reflect or refract the Rays of Light is sufficient to produce different Colours, is not only evident in Cloth held in several Positions, by which means it variously reflects the Rays of Light; but it is further evident, since the Beams of the Sun trajected through a Prismatical Glass, represent a lively and vivid Rainbow, upon any Body upon which they terminate, which may be discerned by the Eye, placed in any Position whatsoever, viz. whether above, or below, or on the side of the Glass. And tho' when the Prism is taken away, the Rainbow disappears, yet nevertheless, the Light, for the time being truly reflected and refracted from the Prism, and reflected again from the Body, which those as the Cartesians suppose, the several kinds of Motions of these Globuli might contribute to vary the Perception of Colours, so I think that without such Globuli, the Rays of Light may variously affect the Eye themselves, as their Motion is varied in order, or degrees of Swiftness when they affect our Sensory, or as their Motion is undulating or more or less direct. But since I pretend not this Discourse to be a complete History of Colours, I shall only in their proper Place deliver some Experiments, which may show the Insufficiency of the Peripatetics and the Doctrine of the Chemists, and in favour of that opinion which I am most inclined to be of; which is, that Colour is a Modification of the Beams of Light, which they receive from the Object, from whence being reflected to the Eye, they cause that Sensation we call Colour. But how they come to be so modified, I shall not take upon me to declare, till I know both what Light is itself, and what figured Corpuscles it consists of, and likewise their Size and Motion: And before I pretend to lay down my Opinion, I would further be satisfied what is the Nature of Refraction, and what degrees of Commixture of Shades with the Light, made in the superficial Parts of a Body is requisite to produce this or that Colour. CHAP. V Of the Nature of Whiteness and Blackness. Part. II. Of the Experimental History of Colours. ACcording to Aristotle it is taught by Demomocritus, that Blackness depends on the Asperity of the Surface of a Body; and Gassendus, who is the first that hath attempted to explain the contrary Colour, viz. Whiteness, mechanically gives us the following Account; Cogites velim (says he) lucem quidem in Diaphano nullius coloris videri, A mechanical account of Whiteness. sed in opaco terminante candicare, ac tanto magis, quanto densior seu collectior fuerit. Deinde Aquam non esse quidem coloris ex se candidi, & radium tamen ex eo reflexum versus Oculum candicare. Rursus eum plana Aquae Superficies, non nisi ex una parte eam Reflectionem faciat: Si contigerit tamen illam in aliquot Bullas intumescere, Bullam unamquamque reflectionem facere, & candoris speciem creare, certa superficiei parte. Ad haec spumam ex Aqua pura, non alia ratione, videri candescere & albescere, quam quod sit congeries confertissima minutissimarum Bullarum, quarum unaquaque suum radium reflectir, unde continens candor alborve apparet. Denique nivem nihil aliud videri quam speciem purissimae spumae ex bullulis quam minutissimis & confertissimis cohaerentis. Sed ridiculum exhibeam, si tales meas Nugas uberius proponem. But tho' this Account be ingenious enough, yet I shall to render it more full: Add, that Whiteness considered as a Quality in the Object, depends on the Asperity of the Surface of a Body, whose Parts are so ranged as to reflect the Rays of Light, not upon one another, but upon the Spectators Eye, and that too, barely by reflecting them as a Looking-glass does, without Refraction; for in most other Colours they are so ranged, as either to alter the Texture of the reflected Light, or to vary it with Shades; but in reflecting the Rays of Light to represent the Body white, it is not only requisite, that the reflected Beams should be unalter'd, but likewise, that they should almost all be reflected back, so that some of them facing one way, and some another, they may obvert themselves to the Eye on which side soever it is placed. To illustrate this Opinion with Experiments and Observations, I shall first observe, that the Colour of the Sun at Midday in clear Wether, is much more near to a Whiteness, than when stained by sublunary Bodies, and than when near the Horizon, where its Rays have a greater Quantity of Atmospherical Parts of Matter to pass through; and Water itself the more it is shined on appears to be much whiter to the Spectators: And I have taken notice, that the Sun when covered with a white Cloud, hath appeared in the Water to be not red, but white: And it is observed by Smiths, that Iron, which when moderately hot appears red, when it hath acquired a higher degree of Ignition, it seems to be white. So those that have weak Eyes complain of too great a Reflection of Light, when the Ground is covered with Snow; and it is attested by several Writers and other Travellers, that the Whiteness of the Sun hath been so great, that in Muscovy and Russia they found the Snow, to reflect the Light so much, that they could see much farther upon snowy Ground, than we here in England where no Snow lies on the Ground; so that they could see their way by the bare Reflection of the Snow, when the Sun did not shine. Tho' I am apt to believe, that the Effect might in some measure proceed from the Clearness of the Air, cleansed of those Steams which sometimes darken it; since it appears, that we are able in a frosty Night by reason of the clearness of the Air, to discern more Stars than at other times. And that white Bodies reflect the Rays of Light most plentifully, and have no native Light of their own appears, since Snow enclosed in a dark Room was not at all visible: But on the contrary it is observed, that white are the most easily discerned in dark Nights. And for a further Confirmation that white Bodies reflect the Rays of Light not only most plentifully, but from themselves; I shall add, that if the Rays of Light, which enter into a dark Room at a small Hole, Light upon a white Wall, they Enlighten the Room much further than if they fall upon any other Colour. And that white Bodies cast most Rays of Light from themselves appears, since, white Paper is not near so apt to be set on fire by a Burning-Glass as black, the concentred Beams being reflected back much more by the one than the other. To which I shall further add, that, I have perceived a much greater degree of Heat, when I have held my Hand in the Sun Beams, with a black Glove on; than when it was covered with a White one. And to show that white Bodies not only reflect the Rays of Light plentifully, but unstained, I shall add, that in a dark Room, when the Rays reflected from a coloured Body, were thrown upon a white Wall, they would represent the Colour of that Body, whereas, if the Beams Reflected from a yellow Body upon a blue, it would make a green. And to these I shall further add, on this occasion, that having cast the Rays of a troubled Water, by the help of a Lenticular Glass, into an upper Room darkened, the concentered Reflections of the glittering Waves at a few Paces distance, represented a white Body; but if we approached near the Place on which those Rays were cast, they only seemed to be Beams reflected from glittering Waves, which appeared like so many shining Scales of Fishes, succeeding each other successively and disappearing again. But if the seeming Whiteness of a River, proceed not from the reflection of the Sun Beams, but the brightness of the Sky, a Storm may cause the Surface of it to appear Black, the Rays of Light, being reflected more inward than outward; except near the Sea Shore, where the Surface of the agitated Water is covered with Froth. The Surfaces of White Bodies Specular. But to show, that the Surfaces of white Bodies are Specular, I shall Subjoin, that drops of Mercury being raised, by a convenient heat in an Alembick, represented so many looking Glasses, but caused the sides of the Glass they stuck to, to appear White: And it's observed, that if we look upon the Milky Way or galaxy, with a Telescope, tho' to our Eye it appears White, by the help of that we shall discover, that that Whitness only depended upon a Collection of the Rays of Light, whose confused Beams represented to the Eye, a white Body; and why for a like Reason, the Superficies of a Body, which to the Eye reflects the Beams confusedly may not appear White, as well as the Planets which shine by a borrowed Light, I see no contradictory Reason But to return to Experiments, we see, that the whites of Eggs, which are in some measure Natural Speculums, by being beaten into a Froth appear White. And if Oil of Turpentine be mixed with Water, and shaken in a Vial, as the Particles of the Oil are more or less numerous, and minutely divided, it appears more or less White; which Experiment will likewise succeed if tried with a yellow Mixture of crude Turpentine, instead of the Oil; and likewise with an Oil died Green with a Tincture of Copper. And for a like Reason the Water which is carried over with Oils distilled in an Alembick, appears White, as long as the globular Particles of Oil Swim in it; and hot Water is observed to be considerably Whitest and Opacous when the hot Vapours dispered through it, stop the Passages of the Rays of Light, and cause them to fly from it, more plentifully upon the Eye; so that I am apt to think, that the Superficies of white Bodies may as well be convex, as smooth, provided the Superficies be so set with Specular Particles, as to reflect the Rays of Light plentifully upon the Eye; for it is not only observed, that the globular Particles of Oil, make the Water they are mixed with appear White; but the same Colour is likewise reflected, from Powdered Glass, and even several Threads of it laid together; so that it is not, according to the Opinion of some, requisite that the Particles of a white Body, should be altogether Globular. And I have observed, that Snow looked upon, with a Microscope, appeared to consist of slender Icicles of several shapes. And I remember, that by contusion, I have obtained a whitish Powder of Granates, Glass of Antimony, and Emeralds; and the Salt of Venereal Vitriol, Powdered, will comparatively with the Entire Crystals, exhibit a considerable Degree of Whiteness. And as a Body which is not White, may acquire that Colour, by a Change of the Texture of its Parts; so one that is White, may be deprived of that Colour: Thus Silver being first brushed, and then boiled with Salt and Tartar appears White; but becomes Specular by being rubbed with a Piece of Steel, the protuberant Parts, being by that means depressed into a continued Superficies, and reflecting the Image of a lucid Body, whereas before the innumerable little Speculae reflected the Rays of Light more confusedly. 〈◊〉 ●●cha●… Ac● of Blackness. From what hath been said of Whiteness, we may be able to guests in some Measure of the Reason of Blackness, concerning which Quality Gassendus says, Existimare par est, corpora suapte natura nigra constare ex particulis, quarum Superficicculae scabrae sunt, nec facilè lucem extrorsum reflectunt: So that Black differs from White, in as much as the Particles which are reflected externally by the one, are deadened by the other, and not reflected outward, either because the Superficies hath such protuberant Parts, as reflect the Rays internally, or being soft and pliable yield to the Impress of those lucid Parts that strike against them; so a Ball, that would fly back from a Stone, will scarce at all Rebound from a Net or Mud; tho' the latter Explication I think the less propable, because several Bodies are Black, whose Surfaces are scarce of so yielding a Texture, except their peculiar Texture would render them more capable of being worked on, by the Rays of Light, than other Bodies, otherwise softer than they. But whatever is the Cause, why the Beams of Light are very sparingly reflected from Opacous Bodies; that that is the Reason of Blackness will be rendered probable if we take notice, that if a black Substance be held partly in the Sunshine, and partly out, that Part will appear Blackest, which is least Shone upon; and if the rough Surface of a black Marble be well Polished, and brought to the Form of a Concave Speculum, it will represent the Image of the Sun without dazzling the Eyes, and will not in a long time set Wood on Fire, tho' a less Speculum of Matter of a more reflecting Nature would cause it to Flame in a Trice. And to this I shall add, that having set a white and a black Marble Mortar in the Sun, the Black one collected the Rays of the Sun, so as to form a Focus much more conspicuous and hot than the other, by which they were more dispersed, and reflected a glaring Light. And the Beams of a Candle being cast upon two Pieces of Marble, through a round Hole, half an Inch Diameter, the Circle of Light on the Black one, though much less Luminous, was better Defined. And for a further Confirmation of our Hypothesis, I shall add, that when the Rays of Light, fall on the Holes in linen Cloth, or the Mouth of a Well, those Parts are much Darker, the Beams of Light being not reflected back upon the Eye; And even black Velvet, being stroked up and down, seemed much Blacker one way than the other, the silken Piles when inclined, reflecting a greater Number of Rays to the Eye, than the Tops of them were able to do, which make but a small Part of the Superficies: And I have observed, that a Cartload of Carrots, appeared much more Dark when the Ends of them were towards me, than when a greater Number of Rays were reflected to the Eye by the sides of them. And in a dark Room it is observed, that if the Light falls upon a black Cloth, the reflection from it is not near so sensible as if a White one be employed. And I have observed, that a Piece of Tile being partly coloured Black, and partly White, the Red was much hotter than the White, tho' not so hot as the Black Part: And it hath been observed in Italy, that black Marbles exposed to the Sun were much hotter than White ones, tho' it is observed, that the black Marble is much more solid than White. And it is further observed, that Rooms hung with Black are much warmer than others, so that a Lady who was of a Tender Constitution was used to complain that she was apt to take Cold, after she had visited Persons whose Rooms where hung with Black. And I am told, that in hot Countries, Eggs coloured Black, and exposed to the Sun, would be roasted by it. And I have observed them in England to acquire a considerable Degree of Heat by being exposed to the Sun in the Summertime Blackened over. And not only the blind Dutchman, but as Bartholinus says, a blind Earl of Mansfield could distinguish White from Black by the Roughness of the latter. And for these Reasons I am the rather inclined to believe the Doctrine proposed, leaving it to be determined by experience, whether the Beams of Light be reflected from opacous Bodies, and so differently modified before they reach the Eye, or whether from white Bodies they are not moved more briskly. CHAP. VI Experiments in Consort, concerning Whitness and Blackness. EXPERIMENT I. Several Experiments concerning Whitness & Blackness. TO show that the Colours of two diaphanous Liquors, may be destroyed by a Change of Texture; Satiate warm Water with Sublimate, and having filtered it through Cap-paper, to render it clear and limpid; if a few drops of Spirit of Urine be dropped into two Spoonsful of it, the mixture will immediately become White; yet by an addition of Aqua fortis it will again become Transparent, and will become White again, with Spirit of Urine; and the like hath succeeded in other Experiments as well as of these. EXPERIMENT II. IF a Solution of Vitriol be shaken with an Infusion of Galls diluted with Water, it will turn it Black; but by an addition of a few drops of Oil of Vitriol, it will presently lay down its dark Colour and become Transparent; but upon an addition of Salt of Tartar dissolved, it will again acquire a Blackness; and tho' this Ink be pale, yet when Dry, it is very Black. The like succeeded with common Ink, but not so easily, the Operation of the Salts being hindered by the Gum. And here I shall take Notice, that though it be generally allowed, that alkalizate Salts will not precipitate Bodies, except first dissolved in some Acid Menstruum; Yet I have tried, that a Lixivium of Pot-ashes, being poured upon Decoctions of Vegetables, would precipitate a curdled Matter, which would be left behind in the Filtre. And in making the first Ink, several Particles of black Matter, would be separated by a Filtre; and when the Ink was made Clear again by the Oil of Vitriol, the Salt of Tarter seemed to precipitate and to unite those Particles of Matter which were dissolved by the corrosive Oil. And to show, that Galls are not so requisite to the making of Ink, as they are generally supposed, I added a few Drops of a Solution of Vitriol, to a Decoction of Rose Leaves, upon which it turned black, and changed that Colour for a deep Red, when Aqua Fortis was added to it, which was reduced to a Black again by Spirit of Urine. And tho' upon a Mixture of Liquors, mentioned in the Second Chapter of this History of Colours, a black Colour immediately emerges, yet both the Infusion of Orpiment and a Solution of Minium were before they were mixed, limpid and Colourses. EXPERIMENT III. THE Caput Mortuum of white Hartshorn distilled in a Retort will be black, which, that it depends on the change of its Texture only is evident, since the same happens if it be distilled in Glass Vessels: Yet by Calcination in open Vessels, it will regain its pristine Whiteness. Ivory burnt yields a curious black, and so does the burnt Caput Mortuum of Tartar; but if it be throughly calcined it will be white. So white Woods, as Hazel, will yield a black Charcoal and whitish Ashes, and even Animal Substances grow black by being burnt, and white when perfectly calcined. EXPERIMENT IU. THO' it be held as a Maxim by some Philosophers and most Chemists, viz. Adusta nigra, sed perusta alba, yet I have tried, that Alabaster burnt yields a Yellow; and Led calcined forms a red Minium, which urged further by the fire, turns to a Glass darker than Minium. So likewise white Calx of Antimony yields a Glass of a red Colour, deeper than the Calx of Antimony. And tho' common Glass of Antimony adulterated with Borax is of a more diluted Colour, yet by being urged with a violent fire, it's Colour was heightened. Blue Vitriol burnt till it may be rubbed to a Powder betwixt one's Fingers, will acquire a white Colour; but if urged by a greater Heat, it will pass through other Colours, as Grey yellowish and red, and when it is almost calcined throughly, it will be of a dark Purple, near to a black Colour. To these I may add, that Crocus Martis per se, is not so near a White, as the Iron it is prepared from. And that judicious Traveller Bellonius tells us, that a white Charcoal is made of the Wood of Oxyceder. EXPERIMENT V. THO' Camphire kept in close Glasses would not lose its Colour by Heat, yet being set on fire in the free Air, it emitted Smoke copiously, and a Concave Glass with a Hole in the Middle being turned upon it, it continued burning, and covered the inside of the Glass, with a black Soot, which was so copious, that the whole Substance of the Camphire seemed converted into Soot. EXPERIMENT VI. rectified Oil of Vitriol being gradually mixed with Essential Oil of Wormwood drawn over with store of Water in an Alembick, this Mixture was distilled in a Retort, where the Caput Mortuum that remained was black; and the like succeeded with Oil of Winter-Savory made use of instead of the Oil of Wormwood. EXPERIMENT VII. TO render yellow Wax white, put a sufficient Quantity of it into a Bolt-head, with Spirit of Wine, and place it in a Sand-heat, gradually increased till the Wine gins to boil; and then, the Wax being melted, the Mixture will be white; which, upon an Evaportion of the most subtle Parts of the Wine will subside into less Room than before. And one thing remarkable in this Experiment is, that the yellow Colour will neither remain in the Wax, nor the Spirit of Wine separated by a Filtre of brown Paper whilst it is hot. EXPERIMENT VIII. TWO Parts of Sublimate being mixed with one of Tin-glass and sublimed together, the Matter which ascended was of a peculiar Texture, made up of thin, smooth, soft and slippery Plates, much like the Scales of Fishes, and of a shining Colour, much like Orient Pearls. EXPERIMENT IX. IF a Mixture of Gold and Silver be cast into Aq. Fortis, the Gold falling to the Bottom will be turned black, tho' neither the Silver or Aq. Fortis were of that Colour. It is looked upon by Alchemists, that a Mineral abounds with Gold, if it precipitates a black Powder: And it hath been observed, that Gold and Silver refined would fully white Cloth, by rubbing them on it: And I have likewise taken notice, that Pens would be coloured black, by a Silver case I kept them in. EXPERIMENT X. THAT a Solution of Silver will colour Hair black, hath often been found. And I have observed, that Silver dissolved in Aq. Fortis, and evaporated ad siccitatem, and cleared from their greenish Blewness by a successive Affusion and Evaporation of fair Water; this Calx being laid either upon the Skin or Hafts of Knives, would slain them with a lasting black Colour. EXPERIMENT XI. IN order to discover the Reason of the Blackness of Negroes, and the Colours of Foxes and Hares as well as other Animals, I shall subjoin some Collections I have made for that purpose. And first, though it is believed, that the Blackness of the Skins of Negroes depends on the Heat of the Sun, which in other hot Countries is observed to darken the Complexions of Men, more than in England; yet I am apt to believe, that something else is requisite to the Production of those Colours, besides the Influence of the Sun, since we see that Infants are of the same Colour. Besides, in other Places of the same Latitude, the People are observed to be at the most but Tawny; and several Nations in the Empire of Aethiopia situated almost under the Torrid Zone: And it is observed by Travellers and Navigators, that there are very few Blacks in America, tho' the New World contains many Climates, and reaches from one Tropic to another. And tho' the Danes are whiter than the Spaniards, yet it is observed, that the Swedes who likewise Inhabit those cold Countries are not so white as them. And I have seen several Russians, who were of a much browner Complexion than the Danes, tho' these are said to proceed from a Race of Tartars, for in one Province the Muscovites are observed to be much whiter. And I am told, that Negroes live not far from the Cape of good Hope, which is beyond the Southern Tropic, tho' near the same degree of Latitude Northward, Divers American Nations are not inhabited by Negroes, and the Inhabitants of Candia, some Parts of Sicily, and even Spain are not so much as Tawny Moors. And even the Inhabitants of Greenland are observed to be of an Olive-colour, or a darker Complexion. But nevertheless, that Coldness may in some measure contribute to Blackness or Whiteness, appears from what hath been observed in Russia and Livonia, viz. that Hares and Foxes become white in Winter, and regain their genuine Colours again in the Summer; yet in Curland, as Olaus Magnus relates, they vary not their Colour in the Winter; tho' this Country is only severved from Livonia by the River Dugna, where it may seem too strange to be credited, that so small a compass as that River takes up, should diversity the Effects of Cold so much; and the same Objection may be made in respect of the Moors, since Negroes inhabit on one side the River Cenega, and Tawny coloured People on the other. Another Opinion concerning the Colour of Negroes is, that it was a Curse entailed upon the Race of Cham. But not to shift off the natural Cause of that Colour, by flying to a Principal and Universal Cause, whilst there is no necessity of it; not to urge, that the Curse pronounced by Noah, was, that he should be a Servant of Servants, which was fulfilled, when the Posterity of Sem subdued the Canaanites; I see not why Blackness should be esteemed a Curse, since the Negroes are so much content with it, that they paint the Devil white: Nor do I think Blackness inconsistent with Beauty, since it consists in a Sumetry of Parts and good Features in the Face; so that Blackness cannot reasonably be accounted a Curse, except that Colour causes their Bodies to be more scorched by the heat of the Sun, than if it were white, according to the Doctrine above delivered. But I am rather inclined to think, that they proceed from some seminal Influence, since Negroes, as well as Americans Transplanted, retain their Proper and Native Colours; and Twins which are got by the Portugals and Aethiopian Women, are, sometimes, one of them white, and the other black. And how far seminal Impressions contribute to the differences of Organical Parts, appears from the flat Noses, and Blubber Lips of most Negroes. To which may be added, the little Feet of the Chinese and the Macrocephali mentioned by Hypocrates. And it hath not only been observed, that a sort of Hens want Rumps; but I have seen a Raven perfectly white. To which I shall add, that a Lady, who was a devout Catholic, looking upon the Pebbles at the Bottom of St. Winifred's Well, some time after bore a Child whose Skin was covered with the Resemblance of Red Pebbles. To what hath been said of Negroes, I shall add, that the Epidermis only is black, the Skin under that, being as white as that of the Europeans; so that a Child who had the Measles or small Pox, after those Pimples had broke, was covered with a multitude of white Spots: And it is attested by several, that the Negroes when first born, are red or white like other Children, but in a few days acquire the Colour of their Parents: Nevertheless, some of them that are born under the Torrid Zone, continue white, and are presented to the King, and always wait on him. These are usually, as Purchas witnesses, brought up in Witchcraft, and the People stand in great Awe of them. EXPERIMENT XII. NOT only common Crab's Eyes and Pearls, but Coral and Minium dissolved in Spirit of Vinegar, may be precipitated by Oil of Tartar into white Powders: And not only Silver and Tin, but Led and Quicksilver dissolved in Aqua Fortis will yield a white Precipitate, upon an Affusion of salt Water, and so will Tin-glass; and the Calces will be much better coloured, if they be precipitated with Oil of Vitriol instead of Oil of Tartar. And black mineral Antimony may, by the Salts which concur to the Composition of Sublimate, be turned into a rectified Butter of Antimony, which upon an Affusion of fair Water, will precipitate the white Powder called Mercurius Vitae; and the like Powder may be made of Antimony without any Addition at all: And the like white Substance will be precipitated by an Affusion of Water, upon a Solution of sulphureous Gums in Spirit of Wine. And to these I may further add, that Water being poured upon a red Tincture of Benjamin, drawn with Spirit of Wine, will turn it white: But if such seemingly white Bodies stand for some time, unstirred, a resinous Substance will of itself subside; And if acid Spirits be dropped upon a red Solution of Sulphur in Pot-Ashes, or some other sharp Lixivium, the precipitated Sulphur, before it subsides, will turn the red Liquor white. But though these several Bodies yield white Precipitates, yet all will not, since Gold yields a yellow one, whether precipitated by Oil of Tartar, or Spirit of Sal Armoniac. And Mercury, though when reduced to a Sublimate, whether precipitated by Spirit of Urine or hartshorn, it yields a white Precipitate, yet with a Solution of Pot-Ashes, or other strong Lixiviate Salts, it will let fall an Orange Tawny coloured Powder; And so will Crude Antimony upon an Affusion of an acid Liquor. To which we may add, that any of these fixed Salts being poured upon a Solution of Vitriol, it will yield a Sulphur of Vitriol, not at all white. EXPERIMENT XIII. THOUGH it be in some measure true, that White is a Colour like the Materia Prima, fit to take any Form, and that Black is a Colour which is not to be changed for another; yet it does not hold universally true; for tho' the Ingredients which die a Body Black, by infecting other Ingredients usually hinder it from taking a higher Colour; yet we have made it appear, that Inks of different kinds might be deprived of their Blackness. And I have sometimes turned black Pieces of Silk, yellow, with Oil of Vitriol. And as for Whiteness, we ought not to believe it so easily destroyed without Caution and some Restrictions: For Lead is by Calcination, turned into a red Body; and Tin is reduced into a white Calx, and the common Putty sold in the Shops, is made up of half Tin and half Lead, and yet, notwithstanding the Lead, the Putty is white, without discovering any Mixture of Minium. And so if Copper be mixed by Fusion with half the Quantity of Tin, they will yield a Substance, in which the white Colour is much more transparent, than the reddish Colour of the Copper. And on this occasion I shall add, that Arsenic being colliquated in Copper, blanched it; but the white Mixture being kept upon the Cupel, till the Arsenic flew away, the Copper returned to its Pristine Colour. And to show how much the white Colour of a Metal may obscure the Colour of those it is mixed with, I shall add, that a fourth Part of Gold being mixed with Silver, the yellow Colour of the Gold was not to be discerned; but when it was rubbed on a Touchstone, Aqua Fortis would take off the Silver, and leave the Gold behind it, upon the Stone. EXPERIMENT XIV. A Polished Piece of black Horn being scraped with a Piece of Glass, and laid upon a black Beaver Hat, seemed white enough; but being placed upon white Paper, the Colour of that eclipsed the Whiteness of the Horn, and made it appear like dirty Linen. From which Experiment it appears, that Colours depend neither on substantial Forms, nor the Hypostatical Principles of the Chemists, but on a Reflection of the Rays of Light, variously modified by their new superficial Texture. EXPERIMENT XV. IT is Taught by the Chemists, that Blackness depends on Sulphur adust. But besides what hath been already offered as the cause of Blackness, I shall add, in reference to the Opinion here proposed, that common Sulphur sublimed, is far from black, but it is in a great measure yellow, and rather more than less white than before; and when set on fire to make Oleum Sulph. per campanam, it yields very little Soot; and the Flame yields so little, that it will scarce black a white Sheet of Paper; and it is observed rather to whiten than to black Linen, and makes red Rose Leaves grow pale and not black. And I have seen a Piece of fixed Sulphur, which was kept several Weeks in a violent Heat, yet it had no other Colour when cool, but a pure red. And not only Sulphur, but that sulphureous Body Camphire may be kept in a violent Heat without acquiring any thing of Blackness: Nor will inflammable Spirit of Wine, discolour a piece of Paper held over it whilst it consumes. And Tin caleined, yields not a black, but a white Calx; and not only the Charcoal made of Oxy-Cedar is white, but the Smoke of Tinby Coals is observed rather to blanche Linen than black it: To what hath been said we may add, that the Ingredients of our Ink were not hot but cold; and Juice of Lemons will blacken the Blade of Knife, except it be quickly wiped off, tho' no actual Heat intervenes to adust the Sulphur. And if the Blackness of the Ink depended on adust Sulphur, it might be demanded, what became of those adust Particles, when the Liquor, by a few drops of Oil of Vitriol, lost that Colour. Besides, Soot itself may have its Texture so far altered, as to yield a Crystalline Salt and a transparent Colour. But were it allowed, since Adustion renders some Bodies black, that that Colour depended on a trorrifyed Sulphur, it might be further demanded, what gives torrifyed Sulphur that Colour; and it might be questioned, what makes a Window half shut, at a distance to appear black, since it hath no Access of torrifyed Sulphur upon that Posture, but only the Rays of Light are not so plentiflly reflected by it, as is requisite to affect the Sensory with a more lively Colour; But to conclude. What the Chemists teach of Blackness, to me seems to come to no more, than if in answer to an Enquiry after the Cause of Salivation, they should tell us, that the several kinds of Precipitates of Gold and Mercury, and likewise of Quicksilver and Silver salivate upon Account of the Mercury that abounds in them, where we are still at a loss to know why Mercury should have that Effect. CHAP. VII. Containing promiscuous Experiments about Colours, being the Third Part of the Experimental History of Colours. EXPERIMENT I. Promiscuous Experiments concerning Colours. TO show how much the Diversity of Colours represented by Opace Bodies, depend on the Mixture of the Rays of Light with Shades more or less as to Quantity, or as to Interruption, I shall subjoin the following Notes. Paper stained with several Colours, placed in a dark Room whose Window was Southward, the Beams of Light entering in at a Hole 3 Inches ½ Diameter; the White yielded the brightest Reflection. Red gave a Reflection stronger than Green or Blue, whose Colours were scarce discernible, and of an equal Brightness. Yellow reflected more Light than either Green or Blue. Red reflected more Light than Purple, and so did Blue. Marble Paper sleeked reflected the Rays of Light unstained, but not so bright as white Paper. Purple seemed to reflect more Light, than a dark Green. In compounding Colours by Reflection we observed, that if the Colours were not strong and somewhat glossy, the reflected Rays would not form a compound Colour on the Wall. EXPERIMENT II. I Have often taken notice, that white Linen would receive and reflect the Colour of a red Silk Waistcoat in a Light Room; tho' it be generally believed, that a dark Room is requisite to make the Colour of one Body visible by Reflection from another. EXPERIMENT III. Coloured sheets of Paper held betwixt the Light and the Eye, at the Hole which was made in a dark Room, the Colours were each of them represented to the Eye single, but by placing one sheet of Paper before another, the Rays of Light passing through the Blue and Yellow exhibited a darker Yellow; but a finer Paper which was blue, being made use of instead of the former, they afforded a good Green. The yellow and red represented a dark Orange coloured Red. The Purple and Red, appeared of a deeper Scarlet. Purple and Yellow made an Orange Colour. Green and Red a dark Orange Tawny. Green and Purple, made a Purple more dirty. Blue made the Purple deeper and more lovely. Red Marble and yellow represented a Scarlet; but the Colours which were thus compounded varied much, as the Colours of the Paper were deeper or more slight, and as the Paper differed in fineness. EXPERIMENT. iv IN the aforesaid darkened Room we placed a Triangular Prismatical Glass in a convenient Posture, and observed no less than four Reflections and three Refractions; and by hiding sometimes one Part of the Prism, and sometimes another, See Plat. 5. Fig. 5. we found the Rays of Light as the following Scheme represents (See Plate 5. Fig. 5 The Explication of the Scheme. P. P. P. An Aequilatero-triangular Crystalline Prism, of whose Edges P. is placed next the Sun. A. B. and α. β. Two Rays from the Sun, falling on the Prism at B. β. and thence partly reflected towards C. and γ. and partly refracted towards D. and δ. B. C. and β γ. Those reflected Rays. B. D. and β. γ. Those refracted Rays which are partly refracted towards E. and ●. and there represent a Iris 345, denoting the five Consecutions of Colours, Red, Yellow, Green, Blue and Purple, and are partly reflected towards F. and 3. D. F. and γ 3. Those reflected Rays which are partly refracted towards G. and η Colourless, and partly reflected towards H. and θ. F. H. and 3. θ. Those reflected Rays, which are refracted towards I. and I. and there represent another fainter Iris, the Colours of which are contrary to the former 54321. signifying, Purple, Blue, Green, Yellow, Red, so the Prism in the Posture represents four Rainbows. EXPERIMENT V. WE observed, that in a light Room, the Prismatical Iris might be reflected, without losing any of its Colours, from a flat Looking Glass, the Surface of Water, or a Concave Looking-Glass; and that Refraction did as little destroy their Colours as Reflection: For tho' by a Burning-Glass one Part of the Iris would appear either beyond or on this side the other, yet the Colours would appear as vivid in the displaced Part, as in the other. To which I shall add, that the most part of the Prism being covered with an opacous Body, so that, the Rays falling but on a small Part of it, the Iris was but little, yet the Colour appeared to be the same through a Microscope as to the naked Eye. EXPERIMENT VI. Colour's which appear in a dark Room are so dim, that if the Light of the Sun be let in, they presently disappear; which I experienced by casting the converging Beams of the Sun upon the Prisimatical Iris, by a concave Speculum; and if these Rays only crossed the Rays of the Iris, before they fell to ground, they would likewise disappear. EXPERIMENT VII. TRying whether the Colours of opacous Bodies would be varied, as they were in a different Position in reference to the Eye, or according to the nature of the Lucid Bodies that shine upon them; we looked upon several Pieces of Paper by Candle Light; and found, that Yellow was much fainter, than in the Day. The Red was little altered. A deep Green seemed to be a dark Blue; but, being held by a Blue, appeared Green; and much blewer than at the first, when looked upon by a Yellow. Blue, looked like a deep Purple. Purple was very little altered. Red looked upon with the Yellow, made it appear like brown Cap-paper. EXPERIMENT VIII. SUspecting the Flame of a Candle to be tinged yellow with its Fuel, we looked upon it through a deep blue Glass; and observed, that through that it appeared green; a Colour which emerges from a Composition of an obscure blue and a Yellow. And for a like Reason, at the first sight it is not easy to distinguish a Paper from a light Yellow Paper; and other white Bodies reflecting the Rays of Light less troubled or more sincere than other Bodies. EXPERIMENT IX. A Leaf of Gold being held betwixt the Light and the Eye, seemed full of Pores like a Sieve, and so modified the Rays of Light that came through it, that they appeared to the Eye of a greenish Blue; and the like succeeded with a Leaf of Silver. EXPERIMENT X. I Am told that Lignum Nephriticum is used in the Country where it grows as an excellent Medicine against the Stone; which Virtues Monardes' likewise ascribes to it given in Infusion. An Infusion of this Wood, if it be not too strong will appear, betwixt the Eye and the Light, to be of a golden Colour, except that upon the Top it will be covered with a sky Coloured Circle; but if your Eye be placed betwixt the Window and the Vial, the Liquor will appear to be of a lovely Blue. And this Experiment hath succeeded by Candle Light: If the Liquor be held partly before the Eye and a Light, and partly betwixt the Eye and an Opacous Body, it will half of it seem of a golden Colour, and half a Blue; but if turning your back on the Window you observe the Liquor as it is poured out, it will at the first seem Blue; but when it hath fallen lower, and the Rays of Light penetrate it more, it will seem Particouloured. If a little of this Tincture be poured into a Basin of Water, partly in the Sun Beams and partly shaded, it will afford several pleasing Phaenomena. If some of it be poured upon white Paper, the drops about it will appear of different Colours, as the Position of the Eye in reference to them varies; and when it is poured off, the Paper will be died Yellow; and if this be placed in a Window in the Sunshine, and a Pen held betwixt the Sun and part of the Paper, the Verge of the Shadow next the Body that Causes it will be Golden, and the other Blue. Which Phenomena proceeded from the most subtle Parts of the Wood Swimming in the Water, and in several Positions variously reflecting the Rays of Light. Some of this Liquor being carefully Distilled, it yielded a colourless Limpid Water, a deep ceruleous Liquor remaining behind. Spirit of Wine and Salt of Hartshorn, being mixed together I observed, that it required a certain proportion betwixt the Liquor and the Salt, which enabled it to vary its Colour. So that though I was induced to believe that our Tincture received its Colour from a Salt dispersed through it, yet I suspected, that this Salt would be either altered or incorporated by Acid Salts; and accordingly dropping Spirit of Vinegar into some of the Tincture it lost its Blue, but not the Golden Colour; but upon an Affusion of Oil of Tartar per deliquium, that correcting the Acid Salts, it presently regained its Blue Colour again, the ponderous Tartarous Liquor first altering the Bottom of the Liquor and gradually rising again. And since Kercherus Art. Mag. lucis & umbrae Lib. 1. Part 3. writes something of this Exotic Plant, which agrees not with our account of it, since he says it will according to the difference of the Medium, in respect of Light and its several Positions, vary its Colour; yet from the Account he gives of it, it appears, that the Wood he made use of, was different from Ours since he calls it a white Mexican Wood, whereas ours, as Monardes' witnesses is brought from Nova Hispania, and is not of a White, but a darker Colour, except on the outside, which part is much weaker than the other. Besides, he tells us that his Tincture was like Spring Water when held betwixt the Light, whereas ours is Yellowish or Reddish, as the Tincture is weaker or stronger. And since he tells us, that the Tincture will afford all sorts of Colours, and resume a ceruleous Colour in the Dark, I could wish to know how he was convinced of the Latter; and as for the Former, I have tried that it would not at all Answer. Tho' this I must needs own, that having held a Tincture of Lignum Nephriticum in the Rays of the Sun, in a darkened Room, partly in and partly out, and also, wholly out of the Beams but partly near them, it afforded a much greater Variety of Colours than in a lightened Room. In this Experiment it is not a little to be admired, that the Blue Colour should be so easily destroyed, whereas the Yellow Colour is so durable; and further, that Acid Salts should destroy it and Sulphureous one Restore it. A Corollary of the Tenth Experiment. Acid and Sulphureous Salis adistinguished. THis Experiment may give us a hint towards a Discovery of some way to distinguish whether Liquors abound with Acid or Sulphureous Salts; for if they be Acid, they destroy the ceruleous Colour; if Sulphureous, they restore it. And by this Method we have found, that, tho' it hath been doubted what was the Nature of Quicklime, it abounds with Lixiviate rather than Acid Salts. But of what use this Tincture may be, where neither Acid nor Alkalious Salts are Predominant, I leave to be determined by Experience; since I found not that Spirit of Wine, Spirit of Tartar freed from Acidity, or Chemical Oil of Turpentine would restore the ceruleous Colour of this Tincture, when it disappeared upon a mixture of Oil of Turpentine. EXPERIMENT XI. I Have a flat Piece of Glass, which held betwixt my Eye and the light appears Yellow; but being held so, that it reflects fewer Beams upon the Eye, it degenerates into to a pale Blue. And the same Piece of Glass being held Perpendicular to the Horizon, that Part which the Sun shines on will be of a more dilute Yellow, than the other which is shaded; but if it be held Perpendicular to the Horizon, the shaded Part will be of a Golden Colour and the other Blue; if the Sunbeams pass through it upon a white Paper, they will represent a Yellow; yet the Position may be so varied, as to yield a mixed Colour more or less inclining to Yellow in some Places and in others to Blue. N. 1st In trying of these Experiments, the Sunbeams must fall upon the superficial Parts of one side of the Glass, on which we must take care to keep our Eye. And we have prepared a sort of Glass which would answer our expectation by laying a Leaf of Silver on one side, and urging it with a stronger Fire than usual. And one thing in this Experiment remarkable was, that whereas common Artificers colour their Glass by putting a Calx of Silver, Calcined without corrosive Liquors, and tempered with fair Water, on the Plates of Glass when they burn them, theirs appears Yellow whatever side is held to the Eye, or in whatever Posture, but this of ours held betwixt the Eye and the Light appeared Transparently Yellow; but the Eye being placed betwixt the Light and it, it appeared Blue, and not in the least Transparent. EXPERIMENT XII. IT is worth observing, that, though Painters can imitate most Colours which are to be met in Nature, yet they make use of no more than, White, Black, Red, Blue and Yellow, to produce all their Compositions: Thus Black and White represent several sorts of Grays: Blue and Yellow, Greene's; Red and Yellow, Orange Tawny; Red with a little White, a Carnation; Red with an Eye of Blue, a Purple; and by a Decomposition of all these, they represent what Colours they please. But in producing of Colours it is to be observed, that we must take care that the Pigments be so harmless as not to destroy each others Textures, for then the success will be frustrated. EXPERIMENT XII. WE observed that the Colour of a Body did not only seem compound, when we looked through two Glasses at once upon it, but when the Beams of the Sun were cast through a double Glass, the penetrating Beams would be tinged with the compound Colour. But the Rays of Light cast by reflection on a Sheet of Paper from several varnished Glasses, they were tinged with none of the Colours except Yellow, so that I suspected the Beams of Light to penetrate deeper into that Substance than others, and to be tinged with the Varnish; which Guess I was confirmed in, by spreading a little transparent Varnish of a Gold Colour, on a Plate of Muscovy Glass; for the Rays thence reflected were of a Yellow Colour. EXPERIMENT XIV. I Not only found by Experience, that those Colours, which are by the Schools, taken to be Fantastical, might be compounded with as much certainty as real ones; but that if those Colours were deficient, the resulting Colour would be so too. And amongst those Experiments I made, it was observable, that the Yellow Beams of an Iris passing through a blue Glass were turned Green. And the blue Part of an Iris cast upon Red CIoth, would turn it Purple: And by casting one Part of an Iris upon another Iris made by another Prism, I could compound Colours, which would answer my expectation as well as with those that are esteemed real Colours. EXPERIMENT XV. I Endeavoured to try what alteration would be made in Colours by the use of a Coloured Prism; but I found, that it was too difficult to get such as I desired, since whatever Pigments a Prism was Coloured with, they would make it too Opake for our Purpose. EXPERIMENT XVI. THere are some Liquors which are of themselves devoid of Colour, but when raised in the form of Vapours, for the time have very conspicuous Ones; as Spirit of Nitre and Aqua fortis, which in the form of Vapours put on a Red or a deep Yellow. And I further Observed, that the Beams of the Sun Trajected through these Steams appeared Tinged with their Colour, and so did the Rays of Light, which were received from the setting Sun upon a Piece of white Paper. EXPERIMENT XVII. HAving mixed Coloured Powders together, I observed, that if a Liquor was made use of in the Mixture, the same Colour would not emerge as from the dry Powders. Orpiment and Yellow Ochre being mixed afford a good Green. A Yellow solution of Gold in Aqua fortis being mixed with a blue Solution of crude Copper by shaking yielded a transparent Green: And so did blue and yellow Amel melted together: Whether this compound Colour proceeds from a Union of Rays, or else from the joint Effect they have upon the Retina, as when two Strings sound at the same time they make one united Sound I shall not now stay to Examine; but shall briefly intimate that by a good Microscope I could discern each of the Powders of the Bise and Orpiment Distinct, so that a Transposition and Juxtaposition of Parts may produce a new Colour, by variously modifying and reflecting the Rays of Light that fall upon them. So that Colours being mechanically produced, there is no need of substantial Forms to explicate them; nor do they seem to be such inherent Colours as they would have them to be, since they consist only of a heap of mixed Particles of Matter. Nor does it appear, how these compound Colours should be caused by a Sulphur, which tho' the Ingredients must contain it, cause no such Effect there. EXPERIMENT XVIII. SYrup of Violets being dropped upon Paper, and a yellow Solution of Gold mixed with it, the result was a Red, not a Green, which was occasioned by the Acid Salts in the Solution; so that to produce a particular Colour with certainty by the mixture of Ingredients, it is requisite they should be such as may be mixed without altering each others Texture, for a blue Solution of Copper in Spirit of Urine, made with Syrup of Violets not a Blue, but a Green. EXPERIMENT XIX. TO show that Colours may be altered, without any Change in the Chemical Principles of a Body, I shall urge, that essential Oils or Spirit of Wine being shaken, till Bubbles rise, they will afford, as long as they last, very lively Colours, and so does Water and Soap, made into Bubbles by Children; and so will Bubbles in Oil of Turpentine and thin ones blown of Glass. And I have discerned several Rainbows represented, by holding before my Ryes and the Sun, a Feather or a Piece of black Ribbon. EXPERIMENT XX. ALmost any Acid mixed with Syrup of Violets will turn it Red; but Oil of Tartar per deliquium will turn it Green, and all other Alkalize Salts. And this may discover, what Salts are predominant in Bodies, as well as our Tincture of Lignum Nephriticum: Only it will not be worked upon by so slight and weak Ingredients. EXPERIMENT XXI. Blue Bottle or Corn-weed being Candied preserves its Colour a long time; and when newly pressed the Juice will be Blue; yet Spirit of Salt will turn it Red, and Alkalies, Green; and this being drawn upon a piece of Paper moistened with an Acid, it rendered it Red. A Solntion of blue Vitriol in Water, upon an Addition of a Lixiviate Liquor, or an urinous Salt, becomes Yellow: Whence it appears, that Volatile or Alkalizate Salts change not Blue into Green upon the account of an easy Transition from Blue to Green, but upon the Account of the Texture of them. EXPERIMENT XXII. ITalian Painters being used to imitate Vliramarine Azure, by grinding Virdigrease with Sal Armoniac, and leaving it to rot in a Dunghill; This gave us a hint to pour Oil of Tartar upon a Solution of Verdigrease; which, tho' at first, the Mixture was turbid, yet being settled, it produced a lovely Tincture; and a Lixivium of Pot-ashes, being made use of instead of this Oil, it yielded an Azure something Paler than the former; and if Spirit of Hartshorn be made use of instead of these, a greater variety of ceruleous Liquors may be obtained. The better way to separate these Azure Liquors from their Feces, is by Decentation, than Filtration, the Lquor being, by the latter means usually stained. EXPERIMENT XXIII. THo' the Fumes of Sulphur usually whitens Rose Leaves, yet Oil of Sulphur per Campanam, heightens the Colour of their Tincture. EXPERIMENT XXIV. A Grain of Cochinele dissolved in Spirit of Wine, and afterwards gradually in Water, it gave a Tincture to above 125000 times its weight; which is an Instance of the great Minuteness of the Parts of Matter, and of a vastly minute Division of them. EXPERIMENT XXV. RIpe Privet Berries, being crushed upon white Paper, slain it with a Purple; Yet Spirit of Salt will turn it Red, and a Solution of Pot-ashes, Green; and so will Meserion, and the Juice of Pease. From whence and the like Experiments before premised, it appears, that the Saline Parts of Bodies have a considerable stroke in producing their Colours. EXPERIMENT XXVI. SPirit of Salt being dropped upon several Substances already Red, as Syrup of Clove-july-flower, Berries of Spina Cervina, an infusion of Red Roses, Brasil, and several others, it either made no Alteration, or rendered the Red Lighter. An infusion of Roses was turned into a dirty Colour, by an affusion of a Solution of Pot-ashes; and Syrup of Cloves was rendered a little more inclining to Green. Another Red Infusion was advanced into a Crimson; but the Juice of Buckthorn-berries acquired a lovely Green. EXPERIMENT XXVII. SPirit of Salt had a very small Effect upon the Juice of Jasmin; but Spirit of Urine turned it to a Greenish Yellow; and the Event was much the same when we tried it with those less Oily Leaves, called Snow Drops, which appear about the end of Winter. EXPERIMENT XXVIII. Marigold Leaves, fresh Madder, and early Primroses, etc. being rubbed upon Paper till they Coloured it, they would be turned Red or Green, by Alkalized Liquors; tho' so Acid a Salt as the Spirit of it, rather diluted them, yet it almost destroyed the Colour of the early Primroses; and an Alkalizate Solution turned the Juice of Madder Root Red, as well as the bruised Root itself. From whence it abundantly appears, that the Effects of a peculiar Salt upon the Juices of Vegetables depends on their particular Textures. EXPERIMENT XXIX. A Black-berry full Ripe, and another only Red, being rubbed upon a Piece of Paper, the Juice of the former was turned into a Green by a Lixivium; and one much fainter, by a Urinous Salt, and by an Acid, into a Red. But the unripe Berry was little altered by the Acid, but by the other Juices, received Impressions different from the former. Damask Roses would be coloured Red by an Acid, and Green by an Alkaly; but a Yellow Province Rose by a Solution of Salt of Tartar was turned into a Green Bluish Tincture; but an Acid only diluted the Yellowness of the Leaves. And were I in the Island of Banda, I should try what Effects these Salts would have on the Juice of Cloves, which I am told, are first White, then Green, and afterwards Reddish, and when dried, grow Black; but the Flowers of them are said to be of an excellent Blue. And one thing which deserves our notice is, that tho' Damask, as well as red Roses, give a red Tincture to Water acidulated, yet the one hath a purgative, and the other a binding Quality. And to what hath been said under this Experiment, I shall add, that Mr. Parkinson tells us, that Buckthorn Berries gathered green, and bruised into Allum-Water, yield a yellow; when they are black they yield a Sap Green; and if they grow upon the Trees till the middle of November, they yield a Purple Colour. And Clusius of Alaternus tells us, that the grosser Parts of some Plants differ in Colour from each other; for the Portugal's Dye their Nets blew with a Bark, and blackish blue with the Wood EXPERIMENT XXX. TO show that a change of Colour depends on an Alteration of Texture, I shall add, that the same Matter being sealed up in a Philosophical Egg, it will by Digestion, pass through several degrees of Colours, before it comes to that of the noblest Elixir. And that several Substances will undergo changes of Colour by Digestion, is evident, in rectified Spirit of Hartshorn, Precipitations of Amalgamas of Gold, and Mercury, without Addition, where by a continued Heat, the Silver-coloured Amalgama will be turned into a shining red Powder; which Effects are produced without an Addition or Substraction of Matter, by the bare change of Texture. EXPERIMENT XXXI IN most Tinctures which the Chemists draw, Redness is the common Colour, as well as in more gross Solutions, tho' the Menstruums be colourless; as with Spirit of Wine, from Jalap, Guajacum, Amber and Benzoin, Flowers of Brimstone, Turpentine, etc. And most Acid or Alkalizate Salts will with sulphureous Bodies produce a Red, and so will Glass of Antimony; and I know an Acid which will turn Oil of Turpentine into a Red. EXPERIMENT XXXII. THO' Balsam of Sulphur seems red, as well as other Liquors in a broad Vessel, yet it stains Paper yellow; but a Tincture of Cochenele, never so much diluted, will still remain Red. EXPERIMENT XXXIII. OIL of Turpentine digested upon white Sugar of Lead, yields a red Tincture. EXPERIMENT XXXIV. IF 5 Ounces of Brimstone and Sal Armoniac, be distilled in a Retort with 6 Ounces of Quicklime, in a Sand-Heat gradually increased, a volatile Tincture of Sulphur will be obtained, which is red, tho' none of the Ingredients were so; yet if agitated when the Vessel it's contained in is unstopped, it will yield a white Fume. And sometimes it may be so drawn, that tho' the Fumes are white, yet the Liquor will die the Fingers black. EXPERIMENT XXXV. WE let a Drop or two of Oil of Vitriol fall upon Oil of Aniseeds coagulated, and spread upon white Paper, by which there was a red Colour produced with Heat and Smoke. EXPERIMENT XXXVI. ONE thing to be observed in the Experiments above recited is, that tho' the Colours mentioned, are easily produced; yet some of them presently fade, by the Influence of the Air, or the Intestine Motion of their own Parts. And Parkison tells us, that Berries of that Plant, which bears Turnsol, a Pigment well known in Painter's Shops, when they are at their full Maturity, yield a Juice, which being rubbed upon Paper appears green, but presently degenerates into a bluish Purple, upon the Cloth or Paper; and these being wet in Water, and wrung forth, will give it a Claret Colour. And I have observed the Red Colour of Buckthorn Berry's degenerate into a dirty Grey Colour; yet by the Mixture of an Alkaly or an Acid it would put on a green or red Colour; and the same Success we had when we dropped the same Liquor upon a Piece of glazed Tile. And I have observed, that Silver precipitated in Aq. Fortis, tho' at the first it is white, yet when upon a Decantation of the Liquor, the Superficies becomes exposed to the Air, it presently turns blackish. And I have seen a sort of Pears, which would give a red Tincture to Wine. And it is observed, that Spirit of Wine being kept upon white Salt of Tartar, acquires a red Tincture. But as for the reasons of these things, and also why all Bodies burnt in the open Air almost, are black, I shall leave to Pyrophilus to inquire. EXPERIMENT XXXVII. SPirit of Salt poured on a Solution of Cochinele, or the Juice of black Cherries, renders their Colours clearer; but turns an Infusion of Brasil yellow, the Acid Liquor in both weakening the Spirit on which it falls; for as Crimson is a Red with an Eye of blue, so Yellow is but a dilated Red; and therefore Alkalizated Salts, will not only restore the Infusion of Cochinele and Brasil to Crimson, but will turn the yellow Juice of Madder red, and an Infusion of Brasil to a Crimson. And here it may be worth while to consider, why Blue and Purple seem to be deeper Colours than Red; and therefore the Juices of Plants of either of the two former Colours, may be turned red by Spirit of Salt, or Aqua Fortis; yet Syrup of Violets, should be, on the contrary, turned green by Oil of Tartar and Spirit of Urine, which is a more dilute Colour than Blew. EXPERIMENT XXXVIII. SALT distilled, at a certain time of the Operation yields red Fumes; and Vitriol, though green or blue, comes over in white Fumes; and the like I have observed in the Fumes of several other Concretes. And I have observed, that even Soot hath filled the Receiver with white Fumes; yet neither Spirit of Nitre is red, nor that of Vitriol or Soot white. And to these Observations we may add, that the Empyreumatical Oils of Woods are of a Colour betwixt black and red: And tho' there is so great a difference in the Colours of Plants, yet the distilled Liquors vary not. And it is observed in Sublimation, that the Flowers differ much in Colour from the Fumes that compose them; as red Benzoin yields white Flowers, and Antimony affords Flowers some of them Red and some Grace; and some of them purely white. And it is the Practice of some Glass Men, to make a Blue sublimate of a convenient Proportion of Brimstone, Sal Armoniac and Quicksilver: And it is observed, that Orpiment which is a yellow Substance, yields a Sublimate, amongst which, several red Fumes ascend; and I have seen a Sublimate whose lower Parts were set with reddish Particles, which glittered prettily. EXPERIMENT XXXIX. IF good Spirit of Urine be dropped into a Tincture, or an Infusion of the Flowers of Pomegranates, the Red will be turned into a Green Colour; but by Spirit of Sea-Slat, it will become come a transparent Liquor, which red may be tur'd into a dirty Green, by Spirit of Urine. Oil of Tartar being dropped into Water wherein Leaves of Senna were immersed, it presently appeared red; but the same would not happen upon an Affusion of Oil of Vitriol. Yet red Rose Leaves being put in warm Water, Oil of Vitriol extracted a red Tincture, but Oil of Tartar would not. But we observed, that the Oil of Tartar only hastened the Tincture of the Senna, since the Leaves in a Night's time will yield a Tincture in cold Water, which will not be heightened by Salt of Tartar. And it may be said of the red Rose Leaves, that the Tincture was rather extracted than produced by the Oil: Yet this is observable, that in extracting the Tinctures, the one will not do what the other will; but I have found that Aqua Fortis will do as well as Oil of Vitriol. If upon the red Tincture of Roses decanted, you drop Spirit of Urine, and shake the Viol it is contained in, it will acquire a greenish Blue; which is observable, since the turning of red into blue is a very unfrequent Observation. And in the Passage of this red Tincture to a blue, if it be taken as the Liquor is dropp'n in, it will afford a pretty variety of Colours, so as sometimes to represent the Tincture of Lignum Nephriticum. And if the Tincture be very high, the Spirit of Urine will turn it to a deep Opacous blue; but the Liquor being left open two or three Days, both the blue and the red Colour vanished; the Liquor being of an Amber Colour, and having a feculent Sediment of the same Colour, which seems to be formed of the Roses drawn together by the Acid, and precipitated by the Volatile Salt of the Spirit of Urine, in whose room other sulphureous Salts may be substituted. And on this occasion I shall add, That Having dropped Spirit of Urine into an Infusion of Galls, it presently turned the Red Liquor into a Purple one; but if the Infusion of Logwood were impregnated with acid Spirits of Salt, it would yield neither a Red nor a Purple, but a yellow Liquor. EXPERIMENT XL. TO show that Colours may be generated de novo, and again destroyed; We dropped Oil of Tartar into a Solution of Sublimate in Water, and the Liquor being agitated, it was turned into a deep Orange Colour; but upon dropping in some Drops of Oil of Vitriol, and continuing to shake the Glass strongly, the whole will presently become transparent again. In which the Colour results from a Coalition of the Mercurial Particles with the saline ones, and with the Alkalizate Particles of the Salt of Tartar, which swim up and down in the Oil: But how these uniting come to form such a Substance as reflects such a Colour, I confess myself at a loss to explain. But in Confirmation of the Reason I have given for the Colour of this Precipitate; I shall add, that having sublimed together equal Parts of Sal Armoniac and Sublimate, and dissolved the ascending Flowers in Water, and siltred it, the limpid Liquor turned white upon the Affusion of an Alkaly, and not yellow. And not only by altering the Texture of the Mercury, but by varying the precipitating Liquor, the Success of the Experiment will be different: For if Spirit of Urine be made use of instead of Salt of Tartar, the Precipitate will be of a different Colour from the former. And from Quicksilver itself, without Sublimate, we may prepare a Pricipitate, dissoluble in Water without discolouring it. And the Colour of such Substances so much depends on the Texture of the Parts concurring to the Composition, that tho' in our Experiment, Oil of Vitriol destroys the yellow Colour; yet by the Assistance of Oil of Vitriol, we may make a yellow Precipitate, with Quicksilver and Water alone. And I the rather employ Oil of Vitriol in such Experiments, because it is not only void of Colour, but strong and incisive; for notwithstanding common and undephlegmed Aqua Fortis will not effect the same thing; yet being carefully dephlegmed, it will in some measure answer Expectation. But one thing to be noted in this Experiment, is, That tho' by dropping in Oil of Tartar and Oil of Vitriol successively, the Liquor will regain and lose its yellow Colour, yet the Proportion of the Liquor growing less in respect of the successive additional Drops, the yellow Colour will gradually appear more faint. An Improvement of the fortieth Experiment. If Crude Antimony be boiled in a strong Lixivium, it will yield a sulphureous Sediment, which will settle in yellow Flakes in the Bottom, and will be more apt to take fire than the Powder of Antimony. Therefore considering that Sulphur boiled in a Lixivium, may be precipitated by Rhenish or white Wine; and likewise that by Acids I could precipitate other sulphureous Concretes out of lixiviate Solvents, such as crude Antimony; And tho' common Sulphur yields a white Precipitate called Lac Sulphuris; yet I concluded that Antimony would yield a yellow one, as well by being made by Oil of Vitriol, as Length of time. Wherefore I put a fresh Solution of Antimony into one Glass, and some of the Orange coloured Mixture into another, where by dropping Oil of Vitriol into the latter, it would become transparent, whereas the same Oil would turn the other clear Solution into a deep Yellow. But in this Experiment we are to observe, that the Solution of Antimony must be fresh, otherwise in Winter it will scarce succeed. Reflections on the XL Experiment compared with the X and XX. Tho' the X and XX Experiments show how Acids may be distinguished from Urinous and Alkalizate Salts; yet thence we cannot distinguish Urinous Salts from Alkalous. But by the Preceding Experiment I was enabled to distinguish Lixiviates by their precipitating an Orange Tawny, from a Solution of Sublimate in Water, whereas Urinous Salts would make it either White or Milky. So that by this Experiment I could discover, that Shall Armoniac drawn from an Alkaly, is but a Urinous Salt more refined, the Alkaly separating, and retaining the Sea-Salt mixed with it; for it would not only turn Syrup of Violets green, and Verdigrease Azure, but would precipitate a White Substance from a Solution of Sublimate. And from hence we may not only learn to conclude Affirmatively, but Negatively of the Nature of Salts, since Spirit of Wine and Essential Oils have either no Salt in them, or it is of a peculiar kind, since they will neither turn Syrup of Violets Red nor Green, nor a Solution of Sublimate White or Yellow. I found that Spirit of Oak, tho' it be a Chemical Principle, yet it would turn Syrup of Violets Purple, and destroy the Blewness of a Tincture of Lignum Nephritium, as Acids do, and would corrode Coral like Spirit of Vinegar; but when the Acid Part of this Spirit was separated from the other, it would have no more Effect upon any of those Liquors as Spirit of Wine or Essential Oils. And by this Method we may discover the Nature of most Salts produced either by Art or Nature; And by the same Method here laid down I have observed, several Liquors, which, tho' run per Deliquium, would have no other Effect than Spirit of Wine. And I know how to make a strong saline Body, which will neither Work upon Syrup of Violets, or a Solution of Sublimate. And now to what I have said, it may be seasonable to add, that the Effects of Salts upon a Solution of Sublimate depend on the peculiar Texture, not only of the Solution, but of the Bodies by which it is precipitated; for a Solution of Gold in Aqua Regia will yield a yellow Precipitate, whether Oil of Tartar, Spirit of Urine or Sal Armoniac be added to it; yet Oil of Vitriol, which precipitates a Solution of Silver in Aqua Fortis will have no such Effect. And the Crystals of Silver dissolved, will yield a White Precipitate; whether an Alkaly, or an Acid. was dropped into the Solution, yet Shall Armoniac would not produce the like Effect: So that the Superfluous Moisture being evaporated, the metalline Corpuseles with the saline ones that had imbibed them, coagulated into Salt, as such Solutions usually do, when the Metal hath been precipitated. EXPERIMENT XLI. AN Azure Solution of Copper in Spirit of Urine being shaken with Oil of Vitriol, would become clear as Water. And tho' Aqua Fortis usually extracts a Blue greenish Solution from French Verdigrease, yet being dropped into a Solution of it in Water, it almost rendered it Colourless; but upon an Affusion of Oil of Tartar or Spirit of Urine, it will disclose a Colour somewhat different from the Solution of Verdigrease itself. EXPERIMENT XLII. THE dried Calx remaining after an Evaporation of a Solution of Quicksilver in Aq. Fortis, gave a yellow Tincture; but Quicksilver being put into a Retort with four times its Weight of Oil of Vitriol, and the saline Menstruum being drawn off in a Sand-heat, till a dry Calx remained in the Bottom, tho' this Calx was of a White Colour, it would pass through a Milky Colour to a Yellow upon an Affusion of Water. And Beguinus, Tyr. Chym. Lib. 2. cap. 13. Prepares Turbith Mineral, which he calls Mercurius praecipitatus Optimus, by digesting, and then two or three times Cohobating one Part of Quicksilver with two of Oil of Sulphur, and by frequent Ablutions in hot distilled Water, etc. But tho' this Yellow of ours be a much finer than any in the Painter's Shops, yet it is too dear for ordinary use, were we certain it would agree with oiled Colours. From whence it appears, that a Menstruum which is devoid of Colour, may produce a Colour, being mixed with a White Calx. EXPERIMENT XLIII. TO show that a Colour may be produced by a Liquor that hath neither Colour nor saline Parts, we poured Water on a grey Calx of Vitriol, and tho' at the first the Mixture was of a muddy Colour, yet being shut up in a Viol for some days, the Calx being partly dissolved and shot into Vitriol, gave the Water a vitriolate Colour; and so it did to fresh Water poured on the Calx, when the tinged Liquor was decanted. EXPERIMENT XLIV. BY dropping a few Drops of a Tincture of Cochinele or Brazil into Water; it will acquire a Pinks Colour; from which, by successive Additions, it will pass from that to a fine Red, and from that to a Crimson, and after that, to an Opace Red; and several intermediate Colours may be perceived in its Passage from one Colour to another. But these variations will be more conspicuous if we make use of cylindrical Pipes instead of Viols. And I have observed, that a Tincture of Brazil being put into a Viol, that in the Body of it appeared Blue, but that in the Neck, which the Rays of Light trajected more plentifully, appeared green; and I had a Piece of Glass, which being held betwixt the Eye and the Light seemed clear, and when the Eye was placed betwixt it and the Light, it appeared slightly discoloured; yet, being applied to the Glass it was knocked off, it appeared as green as Grass. And I have had Bottles, which, tho' they were made of the same Materials with the Stopples, were nevertheless different in Colour. And I have a flat Glass, which obverted to the Eye flat, appears like ordinary Window Glass; but if the Edge of it be obverled to my Eye in a convenient Posture, it will appear like an Emerald: And I have had a certain Pigment, which if it lay thick upon a Piece of Paper, would appear to be of a Crimson, but being spread thin on the Paper, it would seem green. And I have likewise observed, that that blue Substance called Litmase being dissolved in Water, gave it a Tincture betwixt Crimson and Purple; yet it stained Paper Blue; and the like Colour was afforded by it on a Piece of flat glazed Earth. And some of the same being dropped into a Glass of Water of the Figure of an inverted Cone, exhibited great-Varietys of Crimson and Purple; and when the Litmase was perfectly mixed with the Water it afforded a glorious Yellow like that of a Topaz, when a few Drops of Spirit of Salt were dropped into it: And if a few Drops of a Solution of Pot-ashes were dropped into it, they Subsiding into the bottom of it would afford a bright dilute Colour in the bottom of the Glass; a Purple above that, and a deep Crimson, betwixt that, and a Yellow, which wrought to the top of the Glass: And if Spirit of Sal Armoniac were poured upon that it would turn Part of the Yellow into a Purple or Crimson. From which Experiments it appears, that as the Particles of a Pigment are nearer or more dispersed, the Colours represented by them Vary. EXPERIMENT XLV. A Preparation of Steel, used as a Succedaneum of Spaw-Waters, and whose Colour was like that of Germane Amethyst; being dropped into Rhenish-Wine afforded a lovely Green, but Water or Spirit of Wine will not receive that Tincture from it. And to satisfy myself that the Effect depended not on any Acidity in the Wine, I impregnated Water with Spirit of Salt, but notwithstanding, it would not receive a green Tincture from the Liquor. And to vary the Experiment, I dropped Alkalizate and urinous Salts into the Green Tincture, by which it put on a dirty and a turbid Colour, but if this essense of Steel was dropped into Water impregnated with Spirit of Salt, a Solution of Salt of Pot-ashes or of Spirit of Sal Armonic would turn it Yellow, the Vitriolate Salt being precipitated by them: And Olaus Wormius takes Notice of a rare kind of Turn-sole, which would communicate a red Tincture to Water; and tho' it would to Wine, yet Spirit of Wine would not be at all Tinged by it, so that Tincture both depends on the peculiar Textures of the Body that receives and that which gives the Tincture. EXPERIMENT XLVI. THe Adventitious Colours of Metals are either such as they acquire by the Action of the Fire upon them; or such as result from the Coalition of Metaline Particles with the Mestruum which dissolves them; or lastly when they are mixed together by Fusion. And first Tin, by the Action of the Fire being calcined, affords a white Calx and Led a Red one; and Copper calcined per se, yields a dark blackish Powder; and Iron by reverberated Flames may be turned into a Crocus, and Mercury may be turned into a Red Powder. And, Besides these more obvious Colours there are several intermediate one's, whilst by the Action of Fire, Metals are a Calcining. And not only the Calces, but the Glasses of Minerals vitrified per se are of Colours different from the Metal; so that I have seen a Glass made of Silver, of a dark Colour. And not only Metals, but Minerals may be brought to yield Colours, by the Action of the Fire, different from their own, as Antimony affords a whitish Grace Calx, and Flowers variously Coloured; and the Calx by being fluxed will yield a Glass of a yellow or reddish Colour. And Vitriol Calcined passes through several Colours before it comes to be of a dark Purple. EXPERIMENT XLVII. AS for the Adventitious Colours produced by the Union of Metals with their Solvents; Gold gives Aqua Regis it's Yellow Colour, but Mercury gives no considerable Colour to Aqua Fortis, except a Greenness or Blewness at the first, which presently disappears. Tin corroded by Aqua Fortis, subsided in the form of curdled Milk or Eggs. Led dissolved in Spirit of Vinegar, affords a clear Solution; and if the Menstruum be drawn off, appears White. Iron dissolved by Oil of Vitriol diluted with Water, yields a Green Vitriolum Martis; but gives a Saffron Colour to Aqua Fortis, or a yellowish Red. Common Silver, such as is coined, gives a Copper Tincture to Aqua fortis; but such as is refined perfectly, gives a bluish Green to Aqua fortis, and Spirit of Vinegar; and being sublimed with Sal Armoniac, it affords a bluish Sublimate: And indeed Copper dissolved in several Menstruums will yield a great Variety of Greenish Blue or bluish Green Colours. But with Spirit of Sugar and Turpentine it affords a Blue Tincture with a mixture of Green. And to show that the Adventitious Colour may result from the Copper itself as well as the Salts which Corrode it, I moistened Dantzick Vitriol with Spittle, and then rubbing it upon a Knife, it gave it a reddish Colour like that of Copper. Saccharum Saturni with Spirit of Turpentine will yield a red Balsam; and that Stone which Helmont calls Paracelsus his Ludus, in a proper Menstruum affords sometimes a yellowish and sometimes a red Solution. And before I leave this Experiment I shall add that if Quicksilver be precipitated out of Aqua fortis with Spirit of Sea-salt, or Sea-salt dissolved in Water, it will subside in the form of a white Powder; but if it be precipitated with an Alkaly it yields a yellow tawny Powder; but if the Menstruum be drawn off without precipitating it, the remaining substance, will vary its Colour, as it is exposed to different degrees of Heat; so that once I observed the white Calx, to remain partly in the bottom of the Vial, of a deep Yellow, and in some part Red, the remaining Part being elevated in the form of a reddish and ash-coloured Sublimate. And Vermilion, is only a Sublimate of Mercury and Brimstone. EXPERIMENT XLVIII. TO show that Metals Associated with other Bodies will afford different Colours, I have given an Instance in Silver, which gave Glass a lovely golden Colour. And I shall now add, that I am told, that Artificers paint Glass yellow with Calx of Silver. And I have obtained a Substance of a saphirine Blue from Shel-silver mixed with Powder of crystal Glass, kept in Fusion two or three Hours, which I attributed to some Copper latent in the Silver. And tho' Copper calcined per se yields a dark coloured Calx, yet it tinges Glass Green; But being kept in Fusion with 100 times its Weight in Glass, it afforded not a green, but a blue Substance, which whether it proceeded from the Action of the Mineral, or it's saline Parts only, or both, I must not stay to inquire. But to proceed, Putty made of Tin and Led Calcined together, being a white Calx gives colliquated Glass the resemblance of white Amel, which will receive into it the Colours of divers Minerals which will endure the Fire: And I have elsewhere taken Notice, that blue and yellow Amel, being compounded will afford a Green. And it is commonly known that the dark Substance called Zaffora will give Glass a blue Tincture. And that dark Substance termed Magnesia from its similar Colour to that of a Loadstone, gives Glass not only Colours different from its own, but in themselves; as a Red, Purplish or Blackish, as the Quantity of it varies; yet it is used to free Glass from that bluish green Colour that it is subject to; and this may serve to confirm what we delivered in the XLIV Experiment, viz. that as the Parts of a Pigment are more closely or set at distance, the Colour will vary. And here it may not be altogether fruitless to advertise, that it may be a good way of trying Oars, and what Metal they most abound with, to try what Colour they give Glass, when mixed in a due proportion, and kept in Fusion in an equal Degree of Heat and length of time. But to proceed to other Instances agreeable to those we have laid down, yellow Orpiment and Sea-salt Sublimed together constitute white Arsenic, and tho' Orpiment is the greater Part of the Composition; yet Arsenic gives Copper a white Colour within and without. In counterfeiting Factitious Gems by Vitrification, it is observed, That calcined Lead, Colliquated with white Sand, or Crystal powdered by successive Ignitions and extinctions, yields a Decoction, of the Colour of a Germane Amethyst: And I have observed, in calcined Led itself, something like the Colour of such an Amethyst: And with Glass of Lead overpowered with other Pigments, you may emulate the Greenness of Emeralds, tho' in several Cases, the Colour of the Lead may vitiate that of the Pigment; and these Colours so much depend upon Texture, that before the aforementioned Mixture acquired an Amethistine Colour, it passed through several intermediate Colours; and the Colours of such Substances may be so much varied by degrees of Fire, that I have had, a Mass of the size of a small Nut, of four distinct Colours. ANNOTATIONS. BUt besides the aformentioned Ways by which Metals may acquire adventitious Colours, there are yet two unmentioned. For I am told, that it is impossible to strike that Colour termed a Bow-dye without the Materials be boiled in Vessels, either made of, or lined with a Particular Metal. The other way of dying Bodies, is with the Solution of Metals in their proper Menstruums; so Gold dissolved in Aqua Regis, will die the Nails and Skin, and Hafts of Knives made of Ivory, not with a Golden Colour, but a Purple, scarce ever to be washed out: And I have already told you, that a Solution of Silver will die the Nails Black. So Brine colours Beef Green or Red, and a certain proportion of Salt-Petre and common Salt Colours Neat's Tongues Red, and such Flesh as would be otherwise White. And to these I shall add, that a Solution of Sulphur of Vitriol or common Sulphur, will Colour Silver with a golden or reddish Colour, for which Reason the Bath Water causes that Effect. And the Juice of Alcanna, which is Green, dies the Skin and Nails of a lasting Red. EXPERIMENT XLIX. Boil a sufficient Quantity of powdered Turmerick with Water, adding to every pound of Water, two Spoonsful of a filtered Solution of Pot-ashes, in a clean glazed Vessel, till by immersing a Piece of Paper, you find the Turmerick to have given its Tincture; then drop into the filtered Tincture a Solution of Roach Allom, the tinging Parts being curdled, will swim up and down in Flakes, and the Liquor will pass through a Filtre clear, leaving the Yellow Parts behind it, which may be dulcified by an Affusion of Water, but this vegetable Lake may be separated from the decanted Liquor without filtration by pouring on a sufficient Quantity of Water; for than it will either swim on the Top or subside to the Bottom, and may be made fit for use by being dulcified with fresh Water, after it hath been gathered by Filtration, and then it must be dried upon a Cloth, under which Bricks Chalk or Paper, is placed to imbibe the Moisture. ANNOTATIONS. THo' it be generally believed, that this Magistracy of Vegetables is only made up of the coloured Parts of the Plants, yet to favour the contrary I shall represent that Allom contains a stony Matter as well as an Acid Spirit; and tho' Workmen in the making of it use a Sea Weed (called Kelp) and Urine, yet natural Allom hath been found in England, a Solution of which, by an Affusion of Lixivium of Pot-ashes would depose a white Curd, which being filtered would leave behind it a metalline stony Calx, very White, little Bits of which, being placed upon a live Coal, would neither melt nor fly away, nor would they wash away in hot Water, so that they were unlikely to be separated from the Vegetable Lake by Ablutions. And to this I shall add, that from the filtered Liquor I have obtained saline Parts, which would Flame at a Candle, and fly away with some Noise; and I have obtained such a Substance from Allom by precipitating it with urinous Salts and even Urine itself; so that sometimes we may think, that we obtain a Precipitate from a Liquor, when it is in a great measure yielded by the Solution of Allom made use of to precipitate it. The abovementioned way of making Lakes, being tried with Madder, it yielded a Red one, and with Rue, it afforded one of the same Colour with the Leaves. But since the Colour is extracted from the Vegetable by the addition of a Lixivium, it is a Question, whether the Lake will always be of the Colour of the Herb, since Lixiviate Salts may not only extract, but altar the Tinctures of Vegetables. And tho', Acids sometimes do, yet we have found by experience, that they will not always restore Colours destroyed by Alkalies, since Syrup of Violets turned Green by an Alkaly, will not be restored to a Blue by an Acid, but is changed to a Red. And I have found, that when the Colour of the Lake was not altered by the Alkaly, it would be much fainter than the Vegetable it was drawn from. But to conclude this Experiment, I shall add, that Allom is not only of use in such like Experiments as these; but also in the Dyers Trade. EXPERIMENT L. HAving a Mind not only to change the Colour of one Body into another, but also to obtain two Substances of distinct Colours from one Body; in order to it I considered, that since Spirit of Vinegar wholly loses its Acidity by working upon Minium, the Solution would alter the Juices of Plants, as Oil of Tartar usually does, and accordingly I found that it turned, an Infusion of red Rose Leaves Green. And further considering, that Oil of Vitriol will precipitate Solutions of Minerals, especially in Spirit of Vinegar, and that the Calcesare usually fair and White: Considering these things, I dropped a Solution of Minium into an Infusion of Roses, by which it was turned Green; but dropping on that, Oil of Vitriol, it would precipitate the Lead in the form of a white Powder, and leave in the Liquor a clear and high Tincture of Roses, which appeared when the Experiment was tried in a Glass shaped like an inverted Cone. And this Experiment likewise succeeded, when Spirit of Salt was made use of instead of Oil of Vitriol; but with Aqua Fortis it would not succeed; for tho' that Liquor will heighten the Colour of the Tincture of Roses, yet it will not precipitate the Lead. And as by this means from a Green we obtained a white and red coloured Substance, so a Purple will yield a yellow and a red Liquor; for if instead of an Alkaly, which turns an Infusion of Logwood Purple, I made use of a Solution of Minium, and put one Part of this to two of the Infusion, Spirit of Salt would precipitate a red Substance and leave the Liquor above Yellow. But an Infusion of Logwood being turned Purple by a Mixture of a Solution of Minium, Spirit Sal Armoniac dropped upon them, precipitated a Bluish deep Purple Substance, partly in the form of a Powder and partly Curdled; but upon an addition of Spirit of Salt the remaining Part of the Lead was precipitated in the form of a white Powder; so that there were in the Glass three distinct Colours, viz, a Purple at the bottom, a white Carnation upon that, and upon the top a transparent Liquor, Yellow or Red. But to conclude, I shall add that I would not have my Readers too hastily to think, any of the foregoing Experiments false, tho' they should not succeed upon first Trial, since very slight Circumstances may alter or frustrate the Event of several of them; to Confirm which I shall add the following Instance, viz. that if the Ingredients made use of to die Scarlet, be weighed and mixed never so exactly, and all other circumstances be observed; yet if they are not boiled in a Vessel lined with Tin, the Cochineel will not be able to strike a right Colour. FINIS. Advertisement. THE Works of the Honourable Robert boil, Esq Epitomised, Vol. I. By Richard Boulton, of Brazen-Nose College in Oxford: Illustrated with Copper Plates. Printed for J. Phillip's at the Kings-Arms, and J. Taylor at the Ship in St. Paul's Churchyard. Price Bound 6 s. ☞ The Third Volume of the said Abridgement is now in the Press, and will be Published in Michaelmas Term and sold at the same Places. THE TABLE. A. THE Effects of AIR on Feathers in an exhausted Receiver, page 6, 7 The Force of the Airs Expansion. p. 9, 13, 14, 15, 16, 17 The Specific Weight of a determinate Proportion of Air and Water, page 19, 20 Air produced from Bread, page 38 — from Grapes, page 39, 79, 115 — Grapes bruised, page 41 — Must. page 42 — Apples, page 42, 121, 164, 164, 182 — Plums and Apricocks, page 72, 77, 168 — Pears and Apricocks, page 116 The Production of Air obstructed from Doughty, page 44 — from Pears, page 45 — Paste, page 48, 49, 56, 58 — Raisins, page 49 — Plums and Apricocks, page 51 — Grapes with Spirit of Wine, page 54 — Without, page Ib. — Peaches, page 55 — from Ale in Vacuo, page 59 — Pease, page 60 Amber burnt in Vacuo, page 113 Aq. Fortis mixed with Nitre, page 139 — with Spirit of Wine, page 146 Ale in Vacuo, page 198, 199 Whether Air be contained in the Pores of Water, page 205 Aunts and Mites in a Receiver, page 227 Attraction what, page 234 Of the admirable Rarefaction of the Air without Heat, page 249 Air expanded to 8000 times its Natural Dimensions, page 250 — To 10000 times its Dimensions, page 251 Of the Duration of the Air's Spring, page 253 Of the Condensation of the Air by Cold, page 255 Of the different Extension of Air rarified & compressed, page 257 Of the weakened Spring and unheeded Effects of the Air, page 259 Of the Efficacy of the Air's Moisture, page 272, 273, 341 Of the Insalubrity of the Air, page from 276 to 299 The General History of the Air begun, page 330 What is meant by Air, Ibid. Its Ingredients, page 331 Of the Air's Spring, page 334 Of the Generation of the Air, etc. page 336 Of the Air's Weight, page 363 A Whether Aether is contained in Vacuo Boyliano, page 4, 5, 6 B. A small Bird included in a Receiver, page 93, 103, 209, 221 A Bee in Artificial Air, page 96 A Butterfly in Vacuo, page 105, 227 Beef enclosed in a Receiver, page 68, 124, 176, 180, 187, 188, 192, 197, 198 Beans included in a Receiver, page 133, 144 Butter, page 178 Bread in Vacuo, page 195 Beer in Vacuo, page 198 Blackberrys in Vacuo, page 199 Blood and other Humours expanded, page 218 The reason of Bubbles in Vacuo, page 230 Observations about the Barometer, page 243 A statical Baroscope proposed, page 247 Of the Production of Blackness, page 461, 469. C Colours produced in Vacuo, page 10, 11 Cherries enclosed in a Receiver, page 61, 62, 63, 64, 117, 153 Perfumed Cones in Vacuo, page 109, 110, 111, 112 Camphire in Vacuo, page 114 Cabbages in Vacuo, page 118 Coral, page 167 Cow-heel, page 194 Cream in Vacuo, page 197 CLARET in Vacuo, page 199 A Crawfish, page 207 Caterpillars in Vacuo, Of the Changes of Colours in several Mixtures, page 259, 260, 261, 262, 263, 305, 405 Of Clouds, page 344 Of the Mechanical Production of Colours, page 436, 440. Promiscuous Experiments of Colours, page 483. D. A Duck in Vacuo, page 200, 212 New Diseases caused by Subterraneal Effluvia, page 296 E. The Heart of an Eel in Vacuo. page 210 An Eft in vacuo, page 223 Of the Mechanical Production of Electricity, page 323, 324, 325, 326, 327, 328, 329, 330, 355 F. Flies enclosed in a Receiver, page 86, 105, 225 Frogs in compressed Air, page 87 — In Artificial Air, page 99, 101 — In Vacuo, page 108, 203, 210 Fly-blowings in a Receiver, page 106, 148 Frogspawn, page 106, 148 Flies Eggs in Vacuo, 107 Flesh and Broth, page 185, 186, 192, 193 Of Frogs, page 344 The Influence of the Air on Fire and Flame, page 401 The Relation betwixt Flame and Air, Ibid. Of the Air in reference to Fermentation, Ibid. G. Grapes enclosed in a Receiver, page 64, 135, 162 Gillyflowers in compressed Air, page 90 Goosberrys in a Receiver, page 101, 126, 131, 133 Gillyflowers in a Receiver, page 71, 197 A Gudgeon in Vacuo, page 208 A Greefinch in Vacuo, page 211, 214 H. Hartsborn burnt in Vacuo, page 113, 194 A Statical Hygroscope proposed, page 264 Of the Utilities of Hygroscopes, page 265, 266, 267, 268, 269, 270, 271 Of Hail, page 419 K. A Kitling in Vacuo, page 204 L. Why Liquors ascend in Syringes, page 2●● Of the Production of Light in Vacuo, page 10 A Limon enclosed in a Receiver, page 90, 120, Melted Lead in a Receiver, page 138 Larks with Beef, page 181 — with Butter, page 185 A Linote in Vacuo, page 213 A Lark in Vacuo. page 214 A Leech in Vacuo, page 224 Of Lightning, page 350 An Extract of Mr. Lock's Letter, page 367 Of the Effects of the Air in reference to Life, page 410 M. Milk in a Receiver, page 121, 184, 196 Mercury in Vacuo, page 151 Must, page 42 Minium, page 167 A Mouse, page 212, 220 Why Contiguous Marbles are not easily separated, page 228 Marchasi●es burst by the Airsmoisture, page 274 Metals may be raised in the form of Vapours, page 297, 298 Of the ill Effects of Mineral Fumes, page 293 Of the Celeftial and Aerial Magnets, page 312, 313, 314 Of the Production of Magnetical Qualities, page 315, 316, 317 Chymico-Magnetical Experiments, page 318, 319, 320, 321, 322 Of Mists, page 344 The Effects of the Air on Mineral Substances, page 400, 406 Of Maturation, page 428 N. Nut-Kernels in a Receiver, page 128, 157 O. Orange's shut up in a Receiver, page 67, 83, 84, 88, 119, 149 Oil per deliquium with Spirit of Wine, page 145 Onions in a Receiver, page 69, 81, 159 Oysters, page 177, 207 Of the Effects of the Air on Odours, page 403 Of the Mechanical Production of Odours, page 429, 430, 431, 432 P. Pears included in a Receiver, page 75, 92, 126, 136, 160, 171 Paste enclosed in a Receiver, page 97, 102, 131, 155 Pease in a Receiver, page 104, 128 Paper burnt in Vacuo, page 113 Paste burnt in a Receiver, page 114 Plums in a Receiver, page 40, 127, 129 Peaches, page 74, 169, 170, 172 Antidotes against the Plague, page 294 Why the Plague sometimes ceases unexpectedly, page 295 The Vestigation of Plants, etc. page 410 Q. Quicksilver slacked in Vacuo, page 12 Latent Qualities in the Air, page 299, 310 Whence. p. 300 Of the Manifest Qualities of the Air, page 375, 376, 394 Of the Production of manifest Qualities, page 408, 409 R. Roses in a Receiver, page 83, 89, 165 Radishes with Claret, page 142 Raisins of the Sun, page 39, 158 Rosemary and Water distilled in Vacuo, page 191 A Roasted Rabbit in Vacuo, page 195 Of Rain, page 418 S. Whether Sounds be Propagated in Vacuo, page 8 A Shrew-Mouse in a Receiver, page 85, 91, 94, 103, 148 A Shrew-Mouse in a Wine-Gun, page 94 A Snail in Artificial Air, page 103 Sulphur Viu. in Vacuo, page 114 A Solution of Salt in a Receiver, page 138 Spirit. Sal Armon. with Copper, page 145, 151 Sal Armon. and Oil of Vitriol, page 154 Sheep's Blood in Vacuo, page 196 A Snake in Vacuo, page 202 Steams elevated by the Air. page 222 A Slow-worm and a Leech in Vacuo, page 123 The Reason of Suction, page 232, 236, 238 Saline and Sulphureous Parts in the Air, page 301, 343, 352 — How raised, Ibid. Seminal Principles of all sorts in the Air. page 304 Damascus Steel improved, page 305 The Medium of Sounds, 363 T. Tulips in a Receiver, page 82. 120. 166 A Tube immersed in Water, page 142 Venice Turpentine in a Wind Gun, page 150 Calx of Tin, page 167 Tadpoles in a Receiver, page 217 Of Terrestrial Steams, page 344 Of the Effects of the Air on Tastes page 404 Of the Mechanical Production of Tastes. page 421, 422. 423. 424. 425. 426. 427 V Vinegar with Eels in Vacuo. page 109 Urine in Vacuo, page 123 Violent Leaves, page 196 A Viper in Vacuo, page 201, 213, 215 Of the Production of Vitriol, page 303 The Effects of the Air on Vegetable Substances, page 398 W. Spirit of Wine and Oil of Turpentine in Vacuo, page 141 A Whiteing in Vacuo, page 152, 179 Of Winds, page 359 Of the Production of Whiteness. page 519 The End. Books Printed for and sold by John Tailor at the Ship in St. Paul's Churchyard. In FOLIO. POOL's Annotations on the Holy Bible, with Mr. Clark's Concordance to the same, in 2 Vol. the 3d Edition: Much corrected. Monsieur Thevenot's Travels into Persia and the East-Indies. Phillips' New World of Words; or an Universal English Dictionary, containing the proper Significations and Derivations, of all Words from other Languages, etc. the 5th Edition, with large Additions, and Improvements from the best English and Foreign Authors. Systema Agriculturae, The Mystery of Husbandry discovered; treating of the several new and most advantageous Ways of Tiling, Planting, Sowing, Manuring, Ordering and Improving all sorts of Gardens, Orchards, Meadows, Pastures, Corn Lands, Woods and Coppices; with Monthly Directions for Husbandmen, and the Interpretations of Rukick Terms. the 4th Edit. IMPRIMATUR Liber Cui Titulus, THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. By RICHARD BOULTON. JOHN HOSKYNS, V P. R. S. Vicesimo Septimo Martii, 1699. THE WORKS OF THE HONOURABLE Robert Boil, Esq EPITOMISED. VOL. III. BY RICHARD BOULTON, of Brazen-Nose College in Oxford. Illustrated with COPPER PLATES. LONDON: Printed for J. Phillip's, at the King'-s Arms, and J. Taylor at the Ship in St. Paul's Churchyard. MDCC. TO THE Most Illustrious Prince WILLIAM, Duke of Bedford, Marquis of Tavistock, Earl of Bedford, Baron Russel, and Baron Russel of Thornhaugh, Baron Howland of Streatham; Lord Lieutenant of the Counties of Bedford and Cambridge, and during the Minority of Wrichesly, (commonly called Marquis of Tavistock) his Grandson and Heir apparent, Lord Lieutenant of Middlesex; as also Custos Rotulorum for the said County and the Liberties of Westminster; One of the Lords of his Majesty's most Honourable Privy Council, and Knight of the most Noble Order of the Garter. May it please your Grace, THE Great and Noble Character which you have already obtained in the World, hath justly obliged them both to applaud and admire You; and no Wonder then, that it should raise in me an Ambition to lay this at Your Feet; where whilst I lie secure from the Censure of the World under your Grace's Patronage, I have this great Advantage, that in whatever I can say, in relation to your Illustrious Character, I cannot be Guilty of Flattery; since the World universally agrees, that Your Noble Qualifications are not unworthy so Noble a Prince; Your Sagacity and Judgement not being less conspicuous in State Affairs, than your Virtue and Piety in Divine things; the Former having rendered You both acceptable and serviceable in Council, as the Latter have made You an Eminent and Illustrious Example of Christianity; so that You become serviceable to your Country upon a double score; Your Virtues incite your Admirers to pursue and emulate Good Actions, and your Wisdom and Prudence contribute to the well Governing of a People, who are the more disposed to be Loyal and Good Subjects, the more by Example you promote Religion, which teaches them to obey: Upon which Account we may truly say, that You act not the Politician, but, what is much more difficult, like a Wise and Prudent Statesman; You gain the People not by Stratagem, but Example. But on this Occasion I can make use of no greater Encomiums than what his Majesty hath been pleased to Honour You with, in the Preamble to the Patent which creates you Duke, where He declares, in better Words than I am now Master of, that, as there was no Family in England more conspicuous in Virtue and Piety, so he thought himself obliged to give Testimony of it, by conferring that Honour on You, which You long before deserved. But not to enlarge too much on a Subject which the World is so well acquainted with, I shall need to say no more, than that in Your Illustrious Person we may see all the just Qualifications of an English Nobleman concentered; since your Honour is supported not only by Titles, but Actions; so that Your Character is pure and unspotted, in a World ready to take the least occasion of Calumny and Aspersion. Let me therefore rather admire than endeavour to delineate so Noble and so Great a Character; which be it never so well copied, must come far short of its truly Illustrious Original. I shall therefore only add, that all Your Admirers wish that You may long continue an Ornament of the English Nation, and a Standard of Honour and true Nobility; which are more particularly the Wishes of, May it please your Grace, Your most humble, and most devoted Servant, RICHARD BOULTON. THE PREFACE TO THE READER. HAving already, in the Prefaces prefixed to the two preceding Volumes, intimated the Reasons briefly, why I have placed the Subjects in the Order and Method they there appear in, I shall take the same Method in this. And, First, The Second Volume concluding with those Subjects which are more immediately the Objects of our Senses, viz. Tastes, Odours, and Colours, this Third gins with what our Author hath said in Relation to Cold and Heat; to which is added, what he hath delivered concerning Fire and Flame, and those Bodies which chief affect our Sight. And as for the remaining Part of the Book, it will be so evident to the Reader, that the Subjects bear a Relation one to anooher, that there is no need I should allege any thing else to suggest why I placed them in that Order. And now having thus far at the last performed a Task which hath been so long desired, and which hath hitherto been so well accepted by the Learned; it would be Ingratitude in me not to return them Thanks, for receiving so candidly the Labours of one who values himself upon nothing more than that he hath had the opportunity of passing away his Time in their Service, and in contributing his Endeavours in a Work that may be useful in promoting Natural Knowledge: To do which, is not only the Study, but the Diversion of the Candid Reader's very Humble Servant, R. BOULTON. A Catalogue of Books Printed for J. Taylor, at the Ship in St. Paul's Churchyard. 1. POol's Annotations in 2 Vol. Fol. The 4th Edition now in the Press. 2. Phillips' new World of Words, or an Universal English Dictionary, containing the proper Significations and Derivations of all English Words. The 5th Edition, with Improvements from the best English and Foreign Authors. Fol. 3. The Mystery of Husbandry discovered. The 4th Edition, with large Additions throughout the whole. 4. Archbishop usher's Life and Letters. Published by Dr. Parr, his Grace's Chaplain. Fol. 5. Love's whole Art of Surveying and Measuring of Land made Easie. 4 to. 6. Abbadie of the Truth of the Christian Religion, in Two Parts. 8vo. 7. Quintilians Declamations Englished. 8. Ward's Compendium of Algebra. 9 Bp. Ho●… on the Lord's Prayer. 10. Diogen ●…aertius Lives of the Philosophers, in 2 Vol. English. 11. Edward's Authority, Style, and Perfection of the Scriptures. 12. Plutarch's Morals. 5 Vol. Englished by several Hands. 13. Dr. Eachard's Works. 14. Logic, or the Art of Thinking, done into English by several Hands, The 3d Edition. 15. Esop's Fables, English, with Cuts, the true sort. 16. The Queen's Closet opened. The Tenth Edition with Additions. 17. A large and general Phrase-Book, By W. Robertson, M. A. 18. Dr. Salmon's practical Physic. TO THE Learned and Ever Honoured HANS SLOANE M. D. FELLOW, OF THE College of Physicians; AND SECRETARY TO THE Royal Society. Learned Sir, GRatitude itself does not only oblige me to make a Thankful Acknowledgement of Your Favours, but at the same time, makes the Obligations greater, since the Opportunity of owning Favours received from Eminent Men, makes an Addition to them. And if Gratitude be such a Virtue as carries along with it it's own Reward, and also a future Obligation, it is the greater Satisfaction to Me, that whilst I own your former Favours, I lay a Foundation for a second Acknowledgement; But more, that it gives me the Opportunity of soliciting Your Patronage, which you are so free to give to any thing that may promote Natural Knowledge: The Noble-Design of that Royal Society, in which, Your Station makes you an Useful, but Your Qualifications a more Serviceable Member. And as ●our continual Contributions to the Philosophical Transactions, for which the World is obliged to that Learned and Royal Society, and in Great Measure to You, makes them the more Valuable; so Your Readiness to encourage my weak Endeavours hath given me sufficient Reason to acknowledge myself, Learned Sir. Your Most Obliged and Most Humble Servant, R. BOULTON. THE PREFACE To the READER. Candid Reader. ALthough it is the General Consent of all Learned Men, that the Author 's Works deserve the highest Esteem amongst all Cultivators of Natural Knowledge; yet, it is as common a Complaint that long Apologies and too frequent Excursions interspersed through his Writings make 'em less serviceable to Vulgar Readers, who are unable to carry his Sense along with them, when interrapted too often with Digressions, which have little or no Relation to the Subject under Consideration. And as his Prolix and Complaisant Way of Writing is some Disadvantage to Vulgar Readers; so there are some, who, tho' they have Abilities sufficient to extract the Instructive Part, and to pass over his Prolixities, without losing the Advantage of his Improvements; yet they are not backwards to say, that the Reading of Compliments takes up too much time, and they had rather have the Instructive Part, without his long digressive Excuses, since Men, desirous of Knowledge, and less studious of Compliments, need no Apologies to render Knowledge Acceptable, it being sufficiently recommended to Inquisitive Readers by its own Usefulness. The Consideration of this made me more willing to be concerned in a Work, likely to be useful to vulgar Readers, and Acceptable to All; being desirous and ready, to take any Opportunity of expressing my Willingness to do any thing, that may oblige the Learned World, or tend to the Improvement of Knowledge. For tho' it is not to be denied, but that Compliments are great Ornaments and Arguments of the Candour of a well accomplished Author; yet, it is to be allowed, that, as too many of the finest Flowers may as well intercept the Light of the Sun, as an obscure Cloud, so Compliments may prejudice Knowledge if too frequent, as soon as entertaining Digressions. And if Digressions of any kind be of Disservice to the Reader, and consequently Disadvantageous to the Author, it will be the more acceptable Work, if whilst I endeavour to gratify the Reader, I become serviceable to the Author, in dispersing those Clouds; which, tho' they may seem Gentlemen-like Embellishments, are not so entertaining to Philosophers, who consider things just as they are without Additions of Art or Rhetoric. Having thus briefly given the Reader the Reasons, which induced me to the present Work, I shall in the next place proceed to give an Account of the Work itself. First then, considering that the Author 's Design and Aim was not only to improve Knowledge, but, to use a Motto prefixed to one of his Books from the Illustrious Verulam, Potiùs promovere in multis, quàm perficere in paucis; and since in order to a general intelligible System of Philosophy, he was solicitous of collecting as many Phaenomena as he could, and which might be serviceable in framing such a System; so I have, (that the Author 's Aim and Design might not be prejudiced by an Abstract), taken Care both to Epitomise those things in which he might be said perficere, and likewise have taken Care not to omit the least Phaenomenon which might contribute to the promoting of Natural Knowledge: So that I can justly say, there is nothing in the Author 's Works which is not in the Epitome, except Digressions and Apologies. And as I have taken Care to omit nothing, so I have been as solicitous to draw an Epitome without any Enlargements, which the Nature of the Subjects did not require, or without contracting more than the Subjects would admit. And further, as where the Author has laid down several Historical Truths by way of Notes without Philosophising upon them, his Design being to promote as well as perfect, I have taken Care to avoid any other Connexion than the Author thought such Notes required, so I thought myself obliged to give an Abstract of the Author 's Philosophical Thoughts, where he hath interspersed them with his Historical Truths, that the Work might be more perfect. So that the Reader will have in the following Volume, which contains about 30 Sheets besides the Cuts, as much Matter as in the Original takes up near 200 Sheets, which will not only carry this Advantage with it, that what before would have taken up near two months' time in reading, may be read in a Week, but he will likewise purchase Philosophy at so cheap a Rate, that upon that Account it will undoubtedly be more acceptable, the Price of this Volume coming far short of Forty Shillings, which the Books Epitomised in this Volume almost amount to. But what is the greater Advantage is, that so much Knowledge comprised in so small a Compass, will be more easily accquired by young Philosophers, who in larger Volumes are apt to forget what they left at the Beginning, before they arrive at the End of them: But by this Epitome, a System of Philosophy being brought, almost before the Eye at once, it will be more easily swallowed and digested. But whilst I am considering the Advantages which the Reader will receive by the Abridgement, I am told by the Booksellers, that it is likely to meet with some Disadvantages upon another Account; for it being common for Buyers to estimate the Value of a Book by the Bulk, they may think too great a Price put upon this Volume; And therefore, the Booksellers think it necessary that I should acquaint the Reader, that their Reason will take off that Objection; for besides, the Dearness of Paper, and the Number of Cuts contained in this Volume being so chargeable as to amount to a fourth Part of the Charges of the Book; it is hoped that the Usefulness of the Cuts will excuse the Dearness of it; for to have Printed an Abridgement without 'em, would have made it dearer, tho' of a less Price, the Cuts being as requisite to Illustrate the Author 's Works, as Maps in Geography to render Accounts of the Terraqueous Globe more intelligible. Thus much being said in favour of the Booksellers, I shall now proceed to give a brief Account of the Method I have taken in this Volume, reserving a further Account of the subsequent Volume till the Publication of it. And first, considering that it is the usual Method in Systems of Philosophy, to begin with Generals, and thence to proceed to Particulars; and likewise to lay down Principles in Order to Explain the several Phaenomena of Nature by those Principles; I have in compliance with so reasonable a Method, first laid down the Doctrine of Forms and Qualities, and the Principles by which those Qualities are diversified, from whence likewise arise those various Forms from whence each Particular Quality is derived; and because subordinate Forms depend on the same Principles, and differ only from simple or complex Forms in reference to their Union in Compound Bodies. I have likewise adjoined an Account of them, which Doctrine of Forms and Qualities is further Illustrated by Experiments and Observations annexed by our Author for that purpose: And because there is an Affinity betwixt those Experiments, and those made by our Author on Salt-Petre, to them I have annexed an Abstract of his Essay on Salt-Petre, which is not only a farther Illustration of the Doctrine of Forms and Qualities, but being likewise of equal Force in Illustrating what he delivers concerning those General Affections of Matter, Fluidity and Firmness, I have in the next place laid down what he Teaches concerning those more Catholic Modes of Matter; and since our Author in his Chapter of Fluidity hath likewise taken notice of the Superficial Figures of Fluids', I have to that added what is delivered concerning the same Subject in the Philosophical Transactions, and because the Firmness of Bodies is said to proceed from a Rest in their Parts, I have subjoined to that an Essay of the Motion of the Parts of Solids: And to conclude the first Book, which Treats of the most General Affections of Matter, I have added an Account of the Effects of Languid Motion, and the Propagableness of it through those Catholic Mediums, viz. Fluids' and Solids. And these more Catholic Phaenomena of Nature being Explained in the first Book, to distinguish 'em from Qualities more Particular; in the Second Book I begin with the Doctrine of Particular Qualities, which do not only depend on the Motion or Rest, Shape, Size and Texture of Matter, but likewise on the Structure of the World as now. Constituted, and the Laws of Nature as now Established. And because That Part of the Universe contained in Our Vortex, is the Subject chief of the following Sheets, having first begun with an Introduction to Particular Qualities; I proceed to consider, first the most General Observations in the Earthy Region, and from that proceed to consider Submarine Regions, after which, by way of Introduction to the Region of the Air, I have added an Essay of the Natural and Preternatural States of Bodies, and Particularly of the Air, from which proceeding to Experiments made in the Air, those closing the first Volume; In the second Volume I proceed to what he says further relating to the Air, in which I shall give a further Account of the Method taken in that. Having thus briefly given the Reader an Account of the following Method, I shall without detaining him any longer, subscribe myself the Candid Reader 's Very Humble Servant, R. BOULTON. THE INTRODUCTION, Representing the Grounds and Excellency of CORPUSCULAR PHILOSOPHI. HAVING in the Preface given the Reader an Account of the following Sheets, I shall, by way of Introduction, represent the Grounds and Excellency of the Corpuscular Philosophy, as delivered by our Author. And first: It hath this to recommend it above all other Systems of Philosophy, That it teaches us not, as the Doctrine of the Epicureans does, that the World was made in an Infinite Vacuum, by a Casual Concourse of Atoms; nor as the Cartesians, That Matter, first put into Motion by GOD, convened into a World, as now constituted, by Laws Mechanical only; but it allows the Omnipotent Creator a greater share in the Works of his Hands, teaching that the Motions of the small Parts of Matter, which compose the Universe, were guided by that Wise Architect, who when he had constituted the World, established the Laws of Nature. So that we only endeavour to explain those as now constituted, and how they are Mechanically carried on. In doing of which, it accounts for the several Phanomena of Nature, by Principles more intelligible and clear, than the Doctrine of the Peripatetics; since it is much more easily understood what I mean by Motion or Rest, Size, Shape, Order, Situation, and a Contexture of the Parts of Matter, than by fanciful Ideas represented by the Doctrine of Privation, Substantial Forms, and their Eduction, etc. Nor hath our Hypothesis a less Advantage over the Hypostatical Principles of the Chemists, since it accounts for several Phaenomena, which they are at a loss in; as Eclipses of the Sun, which are brought on, and removed by a Local Motion of the Interfering Body, and those others concerned in the Phaenomenon: Or, to use another Instance, it is easily understood, that the Image of a Man cast into the Air, by a Concave Spherical Looking-glass, are more Naturally accounted for by a Refraction of the Rays of Light than any Hypostatical Principles. But besides the Intelligibleness of our Principles, it is a farther Recommendation, that none are more Primary than Matter and Motion; which is the first General Affection of it, nor can any be more simple: None more Primary, because had the same Parts of Matter been always in the same Place, they could not be diversified; therefore Motion was primarily necessary: Nor could any be more simple, because neither could be divided into Parts of a different Denomination; since all Matter is equally Matter, and all Motion must bear the same Title, considered barely as Motion. And as none can be more Simple and Primary, so none can be more Comprehensive; since Motion, Size, Figure, Order and Texture, may be diversified thousands of ways; and as whole Libraries are made of Letters, so the several Phaenomena of Nature may be explained by the several Varieties of Textures, and other Differences, arising from the various Changes our Principles are subject to. Nor are the most Obvious Phaenomena of Nature alone explained by our Hypothesis, but those Qualities esteemed Occult ones, since the Particles which are concerned in such Compositions, as abound with occult Qualities, are subject to the same Laws, and capable of the like manner of Action; tho' their Parts are so Minute, as to make their Modus Operandi indiscernible. But what is still more an Advantage in our Hypothesis, is that it flies not to an unknown Power, as a Plastic one, or an Anima Mundi, whose Operation is not known, but gives us a Mechanical Account of Things; for the former gives no more Satisfaction, than if one were told, that a Watch tells the Hours of the Day, because made by such a Man; whereas the true Reason is, because the Parts so placed together are in Motion. And the same Instances may serve to show us the Deficiency of the Hypostatical Principles: Besides Ingredients by a bare mixture, being able to effect nothing, nor able to work upon each other, without Motion; those Principles themselves, appear, to be only different Modes of Matter, varied by our Hypothesis. To conclude, There is not any one Phaenomenon which any Hypothesis is able to explain; but a more Intelligible Account may be given by the following. Plate .1. Vol. III. Fig: 1. p: 39 4. p. 17 Fig: 5— p: 317. Fig: 6. p: 37. Fig: 2— p: 37. Fig: 7.— p: 3●. Fig: 3— p: 36. p: 314. p: 314. p: 314. p: 314. Plate .2. Vol. III. p: 281. Fig: 1. Fig: 2. p: 285 Fig: 3. p: 285. Fig: 4. p: 288. Fig: 5. p: 290. Fig: 6. p: 293. Fig: 8. p: 295. Fig: 7. p: 294. Plate .3. Vol. III Fig: 1. p: 296 Fig: 2. p: 296. Fig: 3. p: 297. Fig: 4. p: 297. Fig: 5— p: 299. Fig: 6. Fig: 7. p: 301. Fig: 8. Plate .4. Vol. III. Fig: 1. p: 303 p: 303. Fig: 2. p: 305 Fig: 3. Fig: 4. p: 305. Fig: 5. p: 307. p: 309 Fig: 6. Fig: 7. p: 309. Fig: 8. p: 310. Plate .5. Vol: III. Fig: 1. p: 329. THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. An Appendix to BOOK IU. CHAP. I. Of the Mechanical Production of Cold. TO make it appear, That Heat and Cold, Experiments concerning the Mechanical Origin of Cold. which are generally esteemed two of the most active Qualities, may be mechanically produced or destroyed by a bare change of Texture, or by Alterations otherwise mechanically brought on, without the assistance of the Peripatetic Doctrine of Substantial Forms, or the Hypostatical Principles of the Chemists; I shall subjoin the following Experiments. EXPERIMENT I. A solution of Sal-Armoniac. Having dissolved Salarmoniack in four times its quantity of Water, whilst the Mixture was a stirring, and the Salt dissolving, the Water acquired such a degree of Coldness as to congeal Water, with which the Bottle was wet on the outside, into Ice; but after a Dissolution of that Salt, the Coldness gradually declined. EXPERIMENT II. To try whether the Coldness which the former Mixture acquired, did not rather proceed from the Effect which the Water had on the saline Parts than on the Dispersion of those Saline Parts through the Water; I immerged a Thermoscope in Water, which was so warm as to make the Spirit of Wine ascend; but the same Thermoscope being removed into Powder of Sal-Armoniac warm, it ascended much faster; yet the Weatherglass being conveyed into the Liquor again, and the Salt poured into it, it speedily began to subside, and sunk a Division and ¼ below the Mark it stood at in cold Water, remaining at that Station a considerable time. And the same Experiment succeeded when tried a second time. EXPERIMENT III. Having immersed a Thermoscope in Spirit of Salt, I poured Spirit of fermented Urine leisurely upon it, and observed, that the Mixture by a mutual Conflict growing hot, A Thermoscope immersed in a Mixture of Spirit of Salt and fermented Urine. sensibly raised the Spirit of Wine; which being done, and a Salt obtained from the evaporated Mixture, not much unlike Salarmoniack, it was carefully dried, and being put into Water, in which a Thermoscope was placed, upon its dissolution, whilst it was stirred about, the Spirit of Wine in the Weatherglass gradually subsided. EXPERIMENT IU. Another immersed in Spirit of Roch Allom, etc. Having poured as much rectified Spirit of Roch Allom into a wide mouthed Glass, as was sufficient to cover the globulous part of a Thermoscope, when the Spirit of Wine was equally cooled with the Air about it; we poured into it a volatile Salt, obtained by Sublimation from Salarmoniack, and a fixed Alcali; and tho' upon the joint Action of these two Bodies, a considerable Noise was raised, with Bubbles and Froth; yet the Spirit of Wine began to subside, and continued to do so, till the Spirit of Allom was wholly glutted with the volatile Salt, the whole Descent being the length of an Inch. From this Experiment and the foregoing it appears, That when Alcalies and Acids produce Heat, upon a mutual Conflict which ensues their Mixture, they have not that Effect precisely considered as such; since it is evident, that an urinous Salt mixed with an acid Spirit, viz. of Roch Allom, produces Coldness; and not a true Effervescence. EXPERIMENT V. A Thermoscope in a Mixture of Oil of Vitriol and Sal Armon. One part of Oil of Vitriol being shaken together with twelve parts of Water, the Mixture acquired a little Warmth; but when it was cool, being poured into a wide-mouthed Glass, and a Thermometer immersed in it, when the Liquor in the Thermoscope was equally cool with the external, we poured in a sufficient quantity of Salarmoniack to glut the Acid: The effect of which Mixture was, that upon a cold Ebullition the Spirit of Wine descended an Inch. EXPERIMENT VI. Heat produced by a Mixture of Saltpetre and Oil of Vitriol. Tho' Salt-Peter usually produces a Coldness in Liquors, yet eight Ounces of it being mixed with six of Oil of Vitriol, the Mixture acquired a considerable degree of Heat, emitting Fumes copiously. EXPERIMENT VII. The effect of Gunpowder mixed with Water. Though Gunpowder be a Body so inflammable, yet it evidently imparts a Coldness, if mixed with Water. If a small quantity of Oil of Vitriol be mixed with the Salt formerly made use of, before the Oil hath been mixed with Water, it acquires a considerable degree of Coldness. A Digression about Potential Coldness. Potential Coldness Mechanically explained. Potential Coldness is usually looked upon to be a Quality so absolute, as not to be explicable without the Doctrine of Substantial Forms: But it will easily appear, That it may, without any great difficulty, be clearly explained by Mechanic Principles; if we consider, that the Figure, Shape and Texture of Bodies may be so contrived as to lessen the usual and natural Agitation of Humours about our Sensory, and consequently, the Perception of this Imminution, may cause such a Sensation as is usually termed Potential Coldness; which account being allowed, it will follow, That Potential Coldness is only a relative Quality, depending on the dispersion of the Agents through the Bodies to be cooled by them: According to which Notion, the cold fits in Agues may easily be conceived to arise from an Intermixture of the Parts of some clammy Matter, which before a Dissolution, were unable to cause any considerable Effect in the Mass of Blood; but presently after being mixed with the Blood, produce such a change in the Motion of its Parts, as affects the Sensory with such a Sensation as is usually esteemed Potential Coldness; which Sensation may not only be so produced in Agues, but by a like Cause in other Distempers, and in several Parts of the Body, as in Hypochondriack and Hysterical Cases. To render which Account more probable, I shall subjoin, That I have learned by the Effects of Poisons, that the small Parts of them being interpersed through the Parts of Humours previously disposed, may cause a notable Refrigeration: And I myself have prepared a penetrating Chemical Liquor, a Drop of which being given to an Animal, would cast him into a seeming Sleep; and a little larger Quantity, being by Mischance applied to an aching Tooth, gave the Person a sort of trembling, and almost an universal Refrigeration. And that Coldness may be produced by the Mixture of some subtle Parts of Matter with the Mass of Blood, appears from the following Histories. Famulum habui (says Benivenius, Cap. 56. Abditorum apud Schenk. Lib. 7. de Venen. Obs. 24.) qui a Scorpione ictus, tam subito ac tam frigido Sudore toto Corpore perfusus est, ut algentissima Nive atque Glacie seize opprimi quereretur, verum cum algenti illi solam Theriacam, ex Vino potentiore exhibuissem, illico curatus est. And to this I shall add another, related by Amatus Lusitanus, Cent. 6. Obs. Vir qui a Scorpione in Manus digito punctus fuit, multum dolebat, & refrigeratus totus, contremebat & per Corpus dolores, Cute tota quasi aut puncta, formicantes patiebatur, etc. What Refrigeration depends on. Whether such Refrigeration depends on a sort of Coagulation of the minute Parts of the Blood, or whether it may be produced by a different Determination of the motion of the Parts of those Liquors as to the Lines they move in, I shall not now examine; but shall rather offer it to be considered, since the internal Constitutions of several Parts of the Body are different from each other, and since the Size and Textures of several Agents are also various, whether they may not upon that account have different Effects upon distinct Parts of the Body, for all the Qualities of such Agents do not wholly depend on the Action of the Corpuscles of the Medicine only; but depend on some adventitious Qualities, which they acquire by being mixed with particular Humours and which they may dispose to be more or less worked upon, by the other Efficients of Heat or Cold. And these Conjectures may not be rendered a little probable, by observing, That tho' Spirit of Wine inwardly taken causes Heat; yet externally it abates the Heat of inflamed Parts; but hath different Effects on a tender Eye: And though internally five Grains of Camphire may diffuse Heat through the whole Body, yet externally it is used in refrigerating Medicines. How far these Observations may be of Service in determining whether Camphire, etc. be hot or cold, I shall leave to Physicians to consider, and shall here only offer in Proof, That Potential Coldness is only a relative Quality, the following particulars, viz. That from the VI and VII. Experiments it appears, that according to the Dispositions of Bodies to be worked on, the Agent may have different Qualities: As Fumes of Lead may coagulate Mercury, tho' it hath not a like Effect on other Liquors: And further, although Salarmoniack and Nitre be, when separate, cool, and tho' the latter melted in a Crucible takes not Fire of itself, yet upon an addition of Salarmoniack it flashes vehemently. But I shall leave this Digression, and proceed to Experiments about Cold. EXPERIMENT VIII. Oil of Vitriol poured upon a Solution of Sal-Armon. To make it appear, how much Motion and Texture may contribute to the Production of Cold, we gradually added twelve Ounces of Water to an equal quantity of Salarmoniack; and whilst upon a Dissolution of the Salt, the Water became cold, we poured in twelve Ounces of Oil of Vitriol, upon which the Mixture became hot; where it is not a little strange, that though Salarmoniack in either of these Liquors produces Cold, yet a contrary Effect should happen upon its Mixture with both together: The Reason of which could be no other but that the Heat produced by the two Liquors overpowred the Degree of Cold, which the Salt was able otherwise to produce. EXPERIMENT IX. The Effects of the same Mixtures are so uncertain sometimes, that I have observed, that having placed a Thermometer in eight ounces of Spirit of Verdigrease, and gradually put in two ounces of Salt of Tartar, after some time, the Ingredients having worked upon each other with a copious Froth and a hissing Noise; the Bottle was something warm, and the Liquor in the Thermometer raised: Yet another Salt being mixed with Salt of Tartar, and Spirit of Verdigrease prepared without Spirit of Vinegar, and Spirit of Wine poured upon it, instead of an Incalescence, a considerable degree of Coldness would be produced. EXPERIMENT X. Oil of Vitriol and Water shaken together, upon an Addition of Salarmoniack, acquire a sort of Goolness; but if Oil of Vitriol and the Salt be first mixed, upon an Affusion of Water they become hot: And tho' Salt of Tartar grows hot in Water, yet the Caput Mortuum of Salt of Tartar and Cinnabar, distilled in a strong Fire, produces no Heat, notwithstanding a hissing Nolse like that of Quicklime succeeds its Immersion. A coincident Disposition betwixt the Agent and the Patiented requisite to the production of their Effects. That the artificial Production of Cold may be obstructed by an Indisposition in the Patient, to be acted on by the grand Efficients of Cold, I have learned by several Observations; and particularly by noting that tho' Oil of Vitriol be so fiery a Liquor, as in some measure to have the Effects of Fire itself, and to dissolve Ice sooner than Spirit of Wine; yet a Pound of choice rectified Spirit of Wine being put into a Bottle, except a little at the Top, it was wholly coagulated into a consistent Mass like Ice, notwithstanding the Glass stood in an Elaboratory in which that Oil was never at any other time observed to congeal. And this Phenomenon was the more remarkable, because the Oil continued in that state, when the Wether was too moderate to be the cause of such an Effect; on the contrary I have observed, that Oil of Anniseeds, which usually coagulates with a less degree of Cold than Water, continued undisturbed and transparent, without the least Coagulation, in a very frosty Season; and the like we have observed in Camphire reduced to an Oil by some Nitrous Spirits. But to conclude this Section; If Heat depends on a brisk agitation of the Particles of the Humours about our Sensory, and if Cold be an Effect of a less degree of Motion than that about our Sensory; it appears that an Imminution of that Motion which is requisite to produce Heat, is sufficient to cause the contrary Quality, viz. Coldness. And tho' Cold seems in such a Sense a privitive Quality, yet in as much as the Agent which causes that Imminution acts positively upon the Parts in motion; it may be esteemed a positive Quality, tho' in respect of our Sensory it is but a relative one, as lukewarm Water will appear hot or cold, as the Hand immersed in it hath either been exposed to an intense degree of Cold or Heat. And indeed the principal mistakes which sometimes occur in Discourses concerning Cold, happen upon the account of the ambiguity of that Expression, which sometimes is used to signify the Idea imprinted on the Mind by the advention of an external Object; sometimes for an Imminution of such a Motion as causes Heat, and sometimes for the Object upon a contact of which we perceive Cold. CHAP. II. Showing, that not only our Senses, but common Weather-glasses, may misinform us about Cold. neither our Sensories nor Weather-glasses, infallible Criteria of the degrees of Cold. THO' most Philosophers have hitherto taken the Testimony of our Sensories for the only Criterion, by which they estimated the degrees of Cold; yet since Cold is, in respect of our Organs, only a Relative thing; and since it hath sensible Effects on other Bodies, which are affected by more minute Variations than our Sensories; it may not be amiss to estimate the degrees of it, by the changes it causes on those Bodies that discover it's slighter Variations, as well as by the assistance of our Senses; since neither our Sensories alone, nor common Weather-glasses are too confidently to be relied on in judging of the degrees of it. For Cold being a relative Quality in respect of our Sensories, as the Disposition of the Organ varies, so the same degrees of Cold may seem violenter or more remiss; as it is observed in hot Baths, the most remiss degree seeming hot to those that come out of the open Air, yet Cold and Chilling to those that come out of a hotter Bath into that; the Reason of which appears to be, that the Parts of the cooler Bath are more briskly agitated about our Sensory than the Ambient Air; but when we come out of a hotter Bath, they being less agitated in Respect of that, causes a Cold Sensation by altering and checking the motion of the Humours, which before were briskly agitated about our Sensories. But our Sensories may not only misinform us in such Cases, where they evidently appear to be differently tempered in respect of those Objects; but sometimes, when those Variations in the Dispositions of our Sensories are Caused by unsuspected Agents, or insensible degrees; so we perceive the Air in a cellar much Colder in the Summer, when Bodies accustomed to a warmer Air descended into it. Nay sometimes we judge amiss of the degrees of Cold, when we think our Sensories unaltered; so Air blown out of a pair of Bellows upon the Sensory, by penetrating into the Pores and retardating the Agitation of the Humours, seems Colder than before, yet when blown upon a common Weatherglass, that motion enables it not to depress the Mercury. Besides, sometimes we may be more sensibly affected with Cold, when it depends not on the Qualities of the Air in general; but either on some Steams which are endowed with frigorifick Qualities, as Opium externally applied; or on some chilling distempered Humour in our Bodies. But further, sometimes Bodies appear colder to our Sensories than to a Weatherglass; because the former are more affected by the Density and Penetrancy of the Parts. So water hath appeared cold to our Bodies, See Plate 1. Fig. 1. when by a nice Weatherglass I could not discover, that it was Colder than the Air. Amongst several Trials made with these Weather-glasses, the following were remarkable. Having caused a Glass-Egg with a Stem, (such as Fig. 1. Plate 1. Delineates,) to be blown at a Lamp, the Stem being dipped in Water, admitted into it a Cylinder of Water about half an Inch long, which, when the Pipe was erected, would subside to the Bottom of the Cylinder, just where it rises from the Egg, and there it would stand; but if the Glass-Egg was immersed wholly in Water, or but half way in Quicksilver, the Water would ascend up to the middle of the Cylinder, and subside again when taken out. In this Experiment several times repeated, I observed, That when the Glass-Egg was suddenly removed out of the Water, and immersed in the Quicksilver, the Cylinder of Water would be raised higher; but if it was first immersed in Quicksilver, and thence removed into Water, it would subside, but not near so much as in the open Air. These Trials were made the 26th of June, the Wether being moderate. But being repeated another day when it was windy and rainy, the Aqueous Cylinder upon the immersion of the Thermometer subsided. June 27 in the morning, the Aqueous Cylinder would subside when the Thermometer was immersed in Water; but ascend when it was depressed into Mercury; yet when the water had been kept in a warm Room some time, till it was as warm to the Touch, as the Quicksilver, they would both of them immediately raise the Mercury in the Pipe. The like Experiment being tried in January, in Frosty Wether, the Internal Air being of an equal temper with the External; when the Thermometer was immersed in a shallow Vessel of Water, the Aqueous Cylinder was raised half an Inch; and when it was immersed in a deeper Vessel, it was raised as high again; but soon subsided when taken out into the free Air. From whence it appears, That we may be differently informed of the degrees of Heat and Cold, when we Employ our Organs of Touch, and when we make use of proper Instruments. On this occasion I shall subjoin, that not only Water, but moist Vapours in the Air may cause it to seem Colder to our Sensories, than commonly Weather-glasses discover it to be. And tho' it be generally agreed, that a Themometer only more exactly measures the Effects which Cold hath upon it and our Sensories; yet I myself have taken notice, that at the same time the Wether hath seemed cold to me, when the Weatherglass agreed not with the Information my Senses gave me, which, that it did not proceed from my 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, was apparent; since others were sensible of it at the same time. From what hath been said, it appears, That it is requisite to take notice when Birds and other Animals, whose Perception is more delicate than ours, seem to be affected with Cold, and likewise to examine the degrees of Coldness, as well by Experiments as by the Touch. For a further Confirmation of what I have delivered on this occasion, I shall add what Martinius in his piece of Geography called Atlas Chinensis, says, speaking of the Air of that Populous Country; his words are these. Ad Coeli solique temperiem quod attinet, majus in hac Provincia frigus est, quam illius poscat poli altitudo; vix enim illa excedit gradum secundum supra quadragesimum; & tamen per integros quatuor saepe Menses Flumina omnia adeo duro concrescunt gelu, ut currus equosque ac gravissima etiam onera glacies ferat, innoxie ac securissime transeant: Ex iis etiam ingentia glaciei frusta excinduntur quae in futuram aestatem ad delicias servant. His Mensibus omnes Naves ita in ipsa Glacie defixae sunt, ut progredi nequeant ubicunque illas frigus occupat (quod certo certius circa medium Novembris ingruere solet) per quatuor illos Menses immotae ibi perstare coguntur, neque enim resolvitur Glacies ante Martii initium; haec plerunque Glaciei concretio uno fit die, cum non nisi pluribus fiat Liquefactio. To which he adds what is more for our present purpose, Omnino illud mirum, tantum non videri aut sentiri illud frigus ut Europaeos ad bypocausta subeunda videatur posse cogere, aut in Europa ad Glaciem producendam sufficere, unde ad subterraneas illic exhalationes pro harum rerum Causis indagandis omnino recurrendum est, etc. But tho' I have urged the necessity and usefulness of Weather-glasses, as preferable to the Informations we receive from our Senses; yet, tho' they are not obnoxious to the same Causes of uncertainty, they are apt sometimes to deceive us; since in common Weather-glasses, besides that the external or internal Air may be rarified or condensed by Heat and Cold, the incumbent Atmosphere being contiguous to the suspended Liquor, it may be boyed up by an additional Gravity, as well as Heat, in the Atmosphere and Vice versâ as we have experienced by a statical Baroscope, whose Balance would turn with the 500th part of a Grain. And likewise by conveying a common Weatherglass into the bottom of a deep Pit; and at another time by raising it up to the top of a Church or Steeple, and comparing it at the same time with a more exact Thermometer; for, by this Method, it appeared, that the rising and falling of the Water in the common Weatherglass, depended not on the temperature of the Air as to Heat or Cold, but on the different altitude of the Atmospherical Pillar of Air incumbent on the Water. But besides the Gravity of the Atmosphere, there may be other Causes of the ascent and descent of the Liquor in common Weather-glasses, as well as Heat and Cold. For not to urge, that tho' the height of the same Atmospherical Pillar of Air should seem unaltered, the Weatherglass remaining in the same place; yet the weight of the Air may be increased by the copious dispersion of Vapours and heavy Steams through the Air, and also may be diminished upon a precipitation of those by Dew or Rain; which Effects may perhaps be falsely attributed to different degrees of Heat or Cold. To be satisfied of the truth of what I have here hinted, I tried the following Experiments. I took two Weather-glasses of a more than ordinary length, See Plate 1. Fig. 2d. and 3d. the divisions of one of which were half Inches, and those of the other not much less. The one, which was furnished with good Spirit of Wine (see Plate 1. Fig. 3.) was sealed. The other (see Plate 1. Fig. 2.) was not sealed; but was so contrived, that the Air being shut up in the lower part of the Instrument, might rise with Heat and fall with Cold. In these Thermoscopes I observed, That in that which was sealed, the Liquor regularly ascended in warm Wether and subsided in cold: But in the other, there being a little hole left open at the top, it was remarkable, That tho' when the Atmosphere continued to be of the same weight, it would regularly rise and fall; yet when the Gravity of the Atmosphere was altered, it would not exaltly correspond with the other; for as when the incumbent Pillar of Air was heavier than ordinary, the Liquor would not be raised high enough by Heat, the pressure of that Air resisting it: So, on the other hand, when the Atmosphere was lighter than ordinary; the Liquor in the unsealed Glass would rise too high. So that by comparing the two Thermometers together, See Plate 1. Fig. 4. I could tell, whether the Mercury in the Torrecellian Tube (see Plate 1. Fig. 4) was risen or fallen, and Vice versa; the rising and falling of the Mercurial Cylinder one quarter of an Inch; usually signifies a great disparity betwixt the ascent or descent of the Liquors in the two Instruments. The difference betwixt the height of the Liquors in the two Thermometers last Night, was but 1 or 2 Divisions: To day, the Barometer making it evident, that the Air was much lighter; the Liquor in the unsealed Thermoscope was at 58. Tho' in the other, the number of the Divisions it stood at was but 41; yet a Week ago, when the Mercury in the Barometer was much higher, and the Liquor in the sealed Weatherglass stood at 46, that in the other was no higher than 27. So that in a Week's time the Liquor in the sealed Thermoscope descended 5 Degrees, and that in the unsealed one ascended 31. At another time I observed, that when the Mercury in the Barometer was higher than ordinary, the Liquor in the sealed Glass stood at the 50th Division, but in the other it was fallen to 32 in warm Sun-shiny weather; so that an unheeded change in the weight of the Atmosphere, may have a greater power to compress the included Air in an unsealed Weatherglass, than a considerable degree of warmth may have to dilate it; and consequently it may happen in an ordinary Weatherglass, where the Air is included at the top, that the pendulous Water may rise in warm weather and fall in cold weather. For a further Confirmation of what I have been saying, I shall add, That even Yesternight I observed, that the Mercury in the Barometer being at 39 Inches, the Liquor in the sealed Barometer was at the 40th Division, and in the other at 39 ½ but this Night the Mercury being raised ¼ of an Inch, the Liquor in the sealed Glass risen to 45, the other being depressed to 34 ½. The Night following, the Mercury being raised ¾ of an Inch, the Liquor in the sealed Glass continued at the 40th Division; the Liquor in the other in two Days time having been depressed to the 17th, that is 23 Divisions. Two or three Days after, the Mercury being risen to 30 Inches, the Liquor in the sealed Glass was at 41; the other was depressed below the 9th Division, being 33 Divisions lower than the other. The Day after, the Mercury continuing at the same height, and the weather growing much colder, it subsided uniformly enough; that in the sealed Glass subsiding to the 33 and the other below the lowest Mark of all: Which difference still continued so great betwixt the Liquors of the two Thermometers, because the Air to Day was very heavy; whereas at another time when the Atmosphere was not so heavy, and the Mercury was suspended at 29 Inches and less than a half; the Liquor in the Hermetical Glass stood at 34 when the Liquor in the other was not below 41. But once I observed the difference betwixt the two Weather-glasses to be greater than any I have recorded yet; it being near 45 Divisions. And a few Hours ago I observed, when the Mercury in a Baroscope had risen above ¼ of an Inch higher than it was the Night before, the Liquor in the shank of the Weatherglass was depressed above an Inch below the surface of the ambient Liquor in the Viol, and in the Night was so far depressed, that a Bubble of the external Air made its way out at the bottom of the Tube, and joined with the common Air in the Cavity of the Viol; an Effect which the coldness of the Season could not give one hopes to expect; the Pipe in which the Liquor was contained being 20 Inches long. CHAP. III. Containing some new Observations about the Deficiencies of Weather-glasses, together with some Considerations touching the new or Hermetical Thermometers. Considerations of the deficiency of Weather-glasses. TO excite Men to greater Curiosity and Industry in making Thermometical Experiments, to what I have already said; I shall add the following Considerations: And First, In order to make our Discourses, and what we Communicate to those that are at a distance more satisfactory; Consideration the 1. we are not provided with a Standard of Cold, to estimate and judge of the degrees of it by: For our Senses are by no menas proper Standards, since the same Body that feels Cold to one is not of the same degree of Coldness to another; nor can Thermometers be given as Standards: Since they only show, how far the Air recedes from that degree of Heat or Colndess wherein they were made, and give us no satisfactory account of the temper of the Air at other times; nor do they inform us how to express it, so that it is a very difficult thing, if not impossible, to give a true Standard of Coldness. Besides it is a Quality, for whose differences there are very few distinct Names there being a great many Intermediate degree of Cold, betwixt Lukewarm and Freezing; a●… as well as several degrees of each of those Qualities, for which we have no Names assigned▪ And indeed, the Observations made by a Weatherglass, are so confined, that if a Glass chance to crack, or some Bubbles of Air get in; we are forced to look out for another Instrument, as a Standard of the Air's Heat or Coldness. And further, tho' it be not difficult to include in the Cavity of a Weatherglass, another Body instead of Air; yet it cannot be done, without being liable to receive Impressions from the Atmosphere, when first put up. But tho' it be difficult to get a Standard of Cold for to judge of its degrees by, yet I have sometines thought, That Oil of Aniseeds, which is coagulated in Cold and thawed again in warm Wether; An Ingenious Gentleman proposed to settle a Standard for Weather-glasses, by observing the Effects of such a degree of Cold as is requisite to freeze Distilled Water, and it may be advantageously made use of when strong enough to freeze Water. might enable us to make two Thermometers exactly correspondent: If the ball of the Thermoscope being immersed in Oil of Aniseeds melted, we observe what station the Spirit of Wine stands at, when it just gins to coagulate: But in doing of it we are to observe, That the Cavities of the Glasses and the Quantity of the Spirit of Wine ought to be as equal as can be; otherwise the success will be much more uncertain. Which way of Estimating Weather-glasses, tho' it be not so certain as unquestionably to answer expectation, yet it may be of advantage to come as near as we can to certainty. But Consideration the 2d. Secondly, There is unaccurateness in measuring of Cold by Weather-glasses which may be avoided, yet is not; since sufficient care is not taken, that the Diameters of the Cylinders are exact all along, from one end to another, nor that there be a certain Proportion betwixt the Diameter of the Cylinder, and that of the Pipe. Besides, open Weather-glasses may be more Commodiously contrived for Thermometrical Experiments than those that are commonly made use of; See Plate 1. Fig. 2. (See Plate 1. Fig. 2.) In which, the mouth of the Vial being so closed with cement or wax, that the External Air hath no communication with it but through the Pipe; upon an Expansion or Condensation of the Internal Air, the Liquor hath much more Room to rise and fall in, than the Pendulous Liquor in ordinary Glasses, where the Quantity of Air is much too small in respect of the Proportion of the Cavity into which it must expand itself, when rarified; to make the rising or falling of the Liquor in that, to be so sensible enough. But besides, that this of ours hath this advantage, that the Quantity of Air is greater in respect of the Proportion of the Cylinder, and consequently the Water hath much more Room to play up and down in; it hath this advantage further, that it is much more convenient for our purpose: Since the Ball of it may be immersed in Bodies, whose Coldness we have a mind to measure; and consistent Bodies, as Snow or Ice may be more conveniently heaped about it, than common Weather-glasses. Thirdly, Men too Confidently conclude, that if the Liquor in a Thermoscope rise an Inch higher to day, A third Consideration. than it was the day before, and an Inch higher the next, that the Air must be as Cold again the last day as it was the preceding; since it appears not, tho' we should allow that Cold of itself contracts the Air, That a double degree of Cold must produce a double degree of Condensation exactly; for besides that the different Quantities of Air contained in these Instruments, and the Proportions of Pipes, as well as the degrees of the Expansions considered together are sufficient to render the Hypothesis suspicious: I am inclined to believe, That the Condensation of the Air and the ascent of the Water depend on the Pressure of the ambient Air, as we shall in a little time make appear, and then this Computation will be found to be very fallacious: For we have elsewhere shown, that the forces required to compress Air, is in Reciprocal Proportions or thereabouts, to the spaces comprehending the same proportion of Air; so that if a Cylinder of four Inches be able to resist a Pressure equivalent to ten pounds' weight, when it comes to be compressed into two Inches; an equal force superadded to the former, will drive up that already compressed Air into half the space, which is about an Inch: Whence it follows, that in estimating the Condensation of the Air in a Weatherglass, we must not only Consider how much Space it is made to desert; but also what Proportion that deserted Space bears to the whole Space it possessed before, and to what degree of Density it was brought before the Application of that force: And we must remember, that the resistance of the Included Air is not to be looked upon as that of a weight, which may remain always the same; but that of a Spring forcibly bend, whose resistance is greatest as it is crowded into less Room. The fourth Consideration. Fourthly, we ought to have a regard to the particular Nature of the Liquors employed in Weather-glasses, till we have a more determinate Theory of the cause of Cold: For amongst Liquors, it does not follow, That because the one is most subject to be affected with the highest degrees of Cold, and to freeze; that the other is less susceptible of the lower degrees of it: Since it is observed, That Spirit of Wine receives notable Impressions from fainter degrees of Cold, than Water does, when made use of in Weather-glasses; tho' in our Climate the latter is much more readily turned into Ice. Besides, we are not to conclude, That all Subtle and most Spirituous Liquors must be least capable of being congealed; since Oil of Aniseeds Distilled by a Limbeck, is extremely hot; yet will it be congealed by a much gentler degree of Cold than Water, and will be longer undissolved upon a Thaw. And I know some distilled Liquors, which consist of Parts very penetrating and vehemently Agitated; yet more subject to freeze than the generality of Chemical Oils or saline Spirits. And indeed, if we allow, that Cold depends on a Diminution of the usual motion of the Parts of a Body; I see not, besides those more Catholic Agents which produce Cold in most Bodies they invade; why one Body may not be said to be more or less frigorifick in respect of this or that Body, and not of a third? For Quicksilver will be coagulated by the fumes of Lead▪ which have no such effect on other Bodies; nor can the utmost degree of Cold 〈…〉 power to congeal it, and from 〈…〉 the Jesuit relates it appears, That Water in peculiar Regions may receive such a disposition from the Soil, as to receive strange Impressions of Cold, in respect of the effects it produces there on Humane Bodies. And tho' Opium refrigerates not Water, as I have experienced by the help of a good Weatherglass; yet a few Grains of it presently refrigerate the Mass of Blood; which is not only an argument, That most Liquors have peculiar Textures; but that the Parts of one Body may be so conveniently shaped as to be able, by insinuating into the Pores of another, to stop the Agitation of their Parts. And in favour of what we have laid down, I shall further add, That I know more Liquors than one, which, mingled with Spirit of Wine well dephelgmed, will presently deprive it of its Fluidity; and the like change I have sometimes observed in other Liquors: And I can make a Liquor much of the same temper of Water, that receives a degree of Coldness by the Addition of a certain substance which stops the Agitation of its Parts; that would scarce have any sensible effect on Water. But to proceed to what we have further to offer in favour of our new Thermometers, Considerations concerning the new Thermometers. besides that the Water and Air may be both alternately condensed, without the influence of the Atmosphere's gravity; they have another advantage, That they may be used in several Places, and removed without spilling the Liquor contained in them, or without danger of it being evaporated. Besides they may be safely let down into any Liquor, even the most Corrosive; it we have a mind to examine their In doing of which, instead of Liquors made use of in common Glasses, we employ Spirit of Wine tinged with Cochineal, opened by the most Volatile Spirit of Urine, which is not only in less danger of being froze, but susceptible of the slightest degrees of Cold impressed upon it by external Bodies. But tho' we think these Weather-glasses subject to fewer Exceptions than common ones; yet in estimating, the several degrees of Cold, we look upon them as Instruments to be employed by our Reason, and not quite exempt from those Imperfections, we have imputed to Weather-glasses; since I suspect, that some sort of Steams, penetrateing the Pores of the Glasses, may have other effects upon the Spirit of Wine, than what they have in reference to Heat and Cold: For I once observed, that having immersed the Ball of a Weatherglass in a strange kind of a Lukewarm mixture, the Spirit risen up slowly 8 or 9 Inches in a Tube not above a foot long; and subsided not again much above half an Inch when exposed to the Air a good while after it had been immersed in Water 5 hours. The Chemist Orthelius in his Theatrum Chymicum Vol. 6. tells us, That the Liquor Distilled from the Oar of Magnesia or Bismute, will swell considerably in the Glass it is kept in at the full Moon, and subside at the New; which observation the Jesuit Casatus makes use of as an Argument. And I have observed myself a Tincture of Amber made with rectified Spirit of Wine, undergo several changes, when stopped up in a Bottle, which other Liquors abounding with Spirit of Wine did not; so that not unlikely, if Weather-glasses furnished with different Liquors were kept together in the same Place, there would be some disparity, which could be ascribed to nothing but the peculiar Natures of the respective Liquors, which, tho' of different kinds, may receive the same Colour from the same Metals: So Copper gives the known Colour to Aqua fortis, and affords a fair Solution in Aqua Regis, as well as gives a lovely Blue to Spirit of Urine, or Shall Armoniac; and I have found, that it would give a good Tincture to Chemical Oil of Turpentine. And to show, that even Spirit of Wine in Weather-glasses may be worked upon and influenced by external Bodies, I shall add, That I have observed in one that lay by me some time, emergent Bubbles: Which whether they were only made up of united Bubbles lodged in the Pores of the Liquor, or some Parts of the Wine disposed to Elasticity by frequent alterations; I examine not: But sometimes they have been so great as to possess many Inches of space in the shank of the Weatherglass; which Bubbles, if they be small and lurk about the juncture of the Ball and of the Cylinder; may, by dividing the Spirit in the Stem from that in the Ball, hinder it from rising according to the Changes of the Wether; a Bubble of Air being more dicffiultly removed up and down in the Stem of the Glass, than the Spirit itself; in favour of which, we have elsewhere shown, That Water will pass through a narrower space than Air, except the latter be forced. But to draw near to a conclusion, tho' I have mentioned all these difficulties about sealed Glasses; I would not be thought to do it with a design to set Men upon greater Niceties than are necessary, but rather to excite us to take into our Consideration as many collateral Experiments and Observations; besides those made by our Sensories, on Natural as well as Factitious Bodies, in judging of the degrees of Cold as we can: For tho' Water be thought to be most susceptible of such an intense degree of Cold as destroys Fluidity, yet besides Oil of Aniseeds, I have distilled a substance from Benzoin, which becomes fluid and consistent upon much slighter alterations as to Heat and Cold, than would freeze Water or thaw it: And I have observed likewise, That Amber-grease dissolved in highly rectified Spirit of Wine, or in other Sulphereous or Resinous Concretions dissolved in the same Liquor; will shoot into fine figured Masses in cold Wether, and re-dissolve in warm; others being more rudely congealed. And even in Chemical Preparations of Hartshorn and Urine, I have observed, That sometimes the Spirits would be clear, and at other times would suffer a greater or less quantity of Salt to Crystallise at the bottom; according to the various alterations of the Wether, in point of Heat or Cold. But to bring Instances from more obvious Liquors, it is observed in some Parts of France by the Watermens, That their Boats will carry greater Loads in Winter than Summer; and on frozen Coasts in several Countries it is observed, That Ships draw less Water than on our British Coasts; which is an Argument, that the Water is heavier and thicker in Winter than in Summer. And I myself have poised a Bubble so exactly, with Water in it; that tho' it would swim upon the top of the Water at Night; yet in the Day, when the Sun had rarified the Water it swum in, it would subside to the bottom: And sometimes was so exactly of a correspondent weight with, and so equally poised in the Water, that it would neither subside nor swim upon the top, but move up and down till the Water was either more rarified or further condensed. From what hath been said in this Chapter, it appears, 1st. That by reason of the various predispositions in Bodies, the testimony of our Senses is not to be taken in judging of the several degrees of Cold. 2dly. Tho' Weather-glasses are subject to fewer alterations than our Senses, yet they may misinform us; except we, at the same time, measure the Air's Gravity by other Instruments. 3dly. Our sealed Weather-glasses are highly preferable before common ones. 4thly, To conclude this Chapter I shall add, That I would not have Men easily deterred from making Experiments about estimating Cold; because they may seem disagreeable to vulgar Notions, since I doubt not but that the Theory we have is not only very imperfect, but ill grounded. CHAP. IU. Concerning the cause of the Condensation of the Air, and ascent of Water by Cold in common Weather-glasses. COncerning the Reason, why Water in common Weather-glasses descends upon Heat, and is raised by Cold? there are three Opinions which may deserve our Consideration. The Opinion of the Schools concerning the ascent of Water in Weather-glasses examined. The first is, that of the Schools and common Peripatetics, which teaches, That the external Air condensing that included in common Weather-glasses; it rises to fill up that space deserted by the Air to prevent a Vacuum. But not to urge, That they have not yet proved, that Nature will not admit of a Vacuum, or that it is contrary to the Notion a Naturalist ought to have of Matter; to suppose it to act any thing contrary to its own natural tendency for a public Good: I say not to urge these Arguments, which we have elsewhere made use of; I shall allege the following Experiment. viz. That, Experiments alleged against their Doctrine. If a Bolt-head with a long Stem be made use of to try the Torrecellian Experiment with, the space deserted by the Mercury in the Cavity of the Bolt-head, and from whence the Mercury drove the Air, continues void; the Pendulous Cylinder remaining at 30 Inches, without offering to ascend to prevent a Vacuum. Nor will the Quicksilver rise ¼ of an Inch higher upon the application of cold Bodies outwardly; tho' in a common Thermometer, the same degree of Cold would make Water ascend several Inches. To this I shall add another Argument taken from the consideration of sealed Weather-glasses (see Plate 1. Fig. 3.) in which it is observed, See Plate 1. Fig. 3. That the Air, instead of contracting upon an increase of Cold, expands itself. If it be said, That the Water contracting the Air follows it to prevent a Vacuum; it may be demanded, Why, since Nature causes the one to contract in common Glasses, and the other in sealed ones, to avoid a Vacuum; she does not rather make the Air retain its natural extension than suffer it to be condensed, and then put herself to double trouble, in compelling the Water to ascend contrary to its nature? But not to insist on these Arguments, I shall rather urge, that what is offered by them will not solve the Difficulty; for whether the Water or Air be expanded into a large space, since Glass is impervious to Air and Water; I see not how a Vacuum interspersum and coacervatum can be avoided: For if upon the expansion, no other Body is added and penetrates the Glass to fill the space deserted by some Parts of the expanded Body, there must remain Vacuities betwixt them: Because it is impossible, the same quantity of Matter should completely and adequately fill a greater space by being expanded; the Parts of the Body being only able inadequately to fill it by receding from each other: But were it allowed, that upon the expansion of one of these Bodies, and the condensation of the other, a third Substance harboured in the space deserted by the one; it may be questioned, how such Matter should make its way out again? Mr. Hobbes his Doctrine examined. The second Opinion I shall take notice of, is that of Mr. Hobbes, which is to me partly precarious, partly insufficient, and scarce intelligible; for tho' when he asserts, That the coldness of Liquors depends on their being pressed with a constant Wind, besides that he asserts it without Proof; it will appear from an Experiment shortly to be alleged, That Liquors sealed up in Glasses, and suspended in Liquors not subject to freeze, may be refrigerated; tho' it appears not how they can be raked on by the Wind as his Hypothesis requires. Secondly, I see no necessity, that the Cold should press upon the superficies of the Water in the Shank; since by Cold it will be raised in a Weather-glassess, kept in a still Place and void of any sensible Wind. Besides, he ought to show, Why Air insensibly moved deserves to be styled Wind, and how it is possible such a Wind should raise Water so many Inches by pressing upon it? Nay further, Water poured into a Bolt-head till it reaches into the Stem, will subside when refrigerated, and not rise. And if the Ball of a Weatherglass be encompassed with a mixture of Ice, or Snow and Salt; the Water will readily ascend; which how it will be explained by Mr. Hobbes' Hypothesis, I do not see. Thirdly, Mr. Hobbes allowing not of a Vacuum, I wonder he should tell us, That by a bare Pressure, the Water finding no other Place to recede into, is forced to rise into the shank of the Weatherglass: For since, according to him, the shank of the Weatherglass must be full before; I see not how it should be able to receive the ascending Water, except to use Mr. Hobbes' own words, it can be fuller than full. Besides, it may be further alleged against Mr Hobbes his Doctrine, that it gives us no account of the condensation of the Air by Cold, in Weather-glasses in which the Water descends with Cold and rises with Heat. Fourthly, whereas Mr. Hobbes in explaining the depression of Water in Weather-glasses, attributes it solely to it's own Gravity; it will easily appear, that we must likewise have recourse to the spring of the included Air: For if a Thermometer be placed in the Sun, when the Water in the shank is but a little above the Surface of the Water without the Tube; the rarified Air will depress the Surface of the Water in the Pipe below the other, and sometimes so far, that some of the rarified Air making its way out of the Pipe, as soon as the remaining Air is refrigerated again, the Water will be able to rise up higher into the Tube than it did before. A Modern Opinion examined. The third and last Opinion I shall consider is one held by some modern Naturalists, which ascribes the Ascent of the Water to the Pressure of the Air gravitating upon the Surface of that Water without the Pipe; but supposes that the Air contained in it, is contracted by Cold alone: As for the first Part of this Hypothesis, I readily Assent to it; and the Author's proposed. but am apt to believe that the contraction of the included Air depends on the same Cause, and that the spring of it being weakened by Cold, it is condensed by the same Pressure of the Atmosphere; the weight of the External Air overpowering the weakened Spring of the Internal. In favour of this Opinion I shall add the following Experiments, See Plate 1. Fig. 5. and First, having filled a Vial capable of holding five or six Ounces, half full (See Plate 1. Fig. 5.) and having inverted a Glass Tube into it, about 10 Inches long, much bigger than a Swan's Quill, it being first sealed at one end and filled with Water; the Orifice of the Vial was closed with Cement, so that the External and Internal Air, had no communication with each other: It was placed in a Mixture of Snow and Salt, till the Water in the Bottom of the Vial began to freeze; yet notwithstanding so great a degree of refrigeration, the Water in the Tube did not at all descend; so that either the Air was not condensed by Cold, or the Water descended not to prevent a Vacuum. The Glass being left in this Posture, in our absence, the sealed end of the Pipe flew off; being beaten out by the Intumescence of the freezing Water. Having fixed another Pipe as the former, which was some Inches longer, and drawn very slender at the sealed end, that it might easily be broken; this was set to freeze as the other, yet the Water descended not, but as soon as the top of the Glass-Tube was broke off, the external Air pressing upon the Water, and by the intercourse of that upon the Air; the Water in the Tube subsided 8 or 10 Inches, but risen again when the internal Air was rarified, within half an Inch of the top; and then the Apex being sealed up it was placed in Snow and Salt, yet the Air in the top, had its Spring so weakened by refrigeration, that it was not able to depress the Water; tho' as soon as the Apex was broke off, it subsided several Inches, the external Air pressing upon it. The Experiment being a third time reiterated with 3 ½ of Air in the Pipe, when the Water in the Vial was in some measure froze, it was able to expand itself a little: But when the Apex was broke off, the External Air depressed the Surface of the Water two Inches, but being removed into a warm Room it ascended above an Inch higher than the uppermost Level. Having put so much Water into a Vessel, See Plate 1. Fig. 6. (Such as Plate 1. Fig. 6. Delineates') as was able to fill almost the whole Tube, we caused a Mixture of Snow and Salt to be placed about the Ball of it, yet we perceived not the Water in the least to rise; but if at all, it might well be ascribed to the the Intumescence of some airy Parts lodged in the Pores of the Water. But the Apex of the Tube being broke off under Water, the External Air forced the Water several Inches up into the Cavity of the Pipe. Another Experiment we made with the following Vessel (See Plate 1. Fig. 7) the Stem of this being no thicker than a Raven's Quill tho' several Inches long, See Plate 1. Fig. 7. and the Ball being about as big as a Nutmeg; we dropped a few drops of Water into the Stem which being suspended there, betrayed very slight changes in the Rarefaction or Condensation of the internal Air. Watching therefore when the Air within had raised the Bubble up to the top of the Stem; we immediately sealed it up, and observed, That tho' the sealed Glass was placed in a Mixture of Snow and Salt, the Bubble did not in the least subside: But if the Apex of the Stem was broke off, the Bubble of Water would be sometimes depressed so low, as to fall into the Ball of the Weatherglass. And what was further remarkable, was, That when the Liquor was descending, if the end of the Tube was sealed up; the Water would immediately stop at the place it rested at, when the Pressure of the Atmosphere was taken off: Where it would continue till the Stem was broke open again, and then the Water would be further depressed; as the weight of the Atmosphere was able to overpower the Resistance made by the internal Air. Having made use of such a Vessel (as Fig. 7. Plate 1.) represents and conveyed a pretty Quantity of Water into both the Legs, See Plate 1. Fig. 7. we sealed up the end of the bend Stem; leaving so much Air above it, as we thought convenient: Which being done, we placed the Ball of it in a frame, in which, the Tube hanging down, we could cover the round Ball with Snow and Salt: Upon which the Air in the Stem was able to expand itself so far, that the Water in the longer Leg was raised the length of a Barleycorn higher than before, and depressed as much in the other: But when the end of the Stem was broke open, the Water was raised 2 ¼ Inches in the longer Leg, and depressed so low in the shorter, that several Bubbles risen into the Cavity of the Ball. In which Experiment it cannot be supposed, That the weight of the Water in the shorter Leg could be able, to raise the Water in the other, except by Virtue of its Spring, which being but small, answerable to the Quantity of of it; it cannot be expected that it should have any considerable Effect upon the Air in the other Leg; tho' its Spring were in some measure weakened by Cold. An Explication of the Figures in the first Plate. Fig. 1. p. 12. A. The Ball or Egg. B C. The Stem. D. The little Aqueous Cylinder. Fig. 2. The open Weatherglass mentioned p. 16, 22. Fig. 3. The Sealed Weatherglass, or Thermoscope mentioned p. 16. Fig. 4. The Barometer or Mercurial Standard placed in a Frame B B. mentioned p. 17. Fig. 5. An Instrument mentioned p. 34. A. The Vial. B C. The Pipe cemented into the neck of the Vial, open at C and sealed at B. Fig. 6. p. 35. A. The Bolt-head. B. The small Stem. B C. The Cylinder of Water enclosed. Fig. 7. p. 36. CHAP. V The Experimental History of Cold begun. TITLE I. Experiments concerning Bodies capable of Freezing others. BEfore we proceed to the natural History of Cold, it perhaps may be necessary to consider what Bodies are capable of retaining such Qualities, and what are not; but that being a consideration not so necessary to our present purpose, which is only to set down what Observations we have made in Bodies subject to be froze; I shall only in short take notice, That most Bodies, except fire, are susceptible of actual Cold, and it is a Question whether even that be not rather a state of Matter in such a peculiar motion, than a distinct and particular species of Natural Bodies; since even Gunpowder, and Spirit of Wine before they are set on fire by some other Body are actually Cold. But to proceed to what Observations relate to our Title. Experiments of Bodies capable of freezing others. 1. Bodies cold enough to freeze others are very few here in England; Snow and Salt mixed being most remarkable; which cool the Liquor contained in those Vessels, which are closed up in such mixtures. 2. Snow alone would not freeze Water, as a Mixture of it and Salt does; and tho' Water poured betwixt the Interstices of Snow or Ice freezes; yet there is a great disparity, betwixt exposing it to the Air, and keeping it up in Vessels; and tho' it is froze, when covered with Snow in a Bottle all night, yet that may proceed from the Coldness of the Air, as well as the influence of the Snow. 3. If Nitre, Alum, Vitriol, Salarmoniack, or Sugar be mixed in due Proportion with Snow; they will enable it to freeze, tho' not so intensely as common Salt. 4. Spirit of Salt being shaken together with Snow in the Vials, they caused a Dew which was gathered on the outside the Glass to be froze; tho' the Mixture within was not, and Oil of Vitriol mixed with Snow in a thin Vial, had the same Effect only more intensely. 5. But not only these Acid Spirits had these Effects on the moisture of the Air condensed on the outside the Glasses; but likewise Spirit of Nitre, Spirit of Vinegar, and Spirit of Sugar, the former of these three being very powerful, tho' the latter were not so strongly frigorifick. 6. Spirit of Urine mixed with Snow in a Vial froze the External moisture weakly; but Spirit of Salarmoniack drawn from Quicklime did it powerfully. 7. Spirit of Urine and Oil of Vitriol poured upon Snow, froze moderately. 8. Sal Gem▪ with a sublimate made with common sublimate and Salarmoniack; nay, and with both loaf and Kitchin-Sugar; as likewise a strong solution of Pot-ashes mixed with Snow did freeze, tho' very faintly. And both a Solution of Salt of Tartar and Pot-ashes Agitated with Snow in a small Vial, produced Films of Ice on the outside the Glass, tho' very thin ones. 9 A sweet Solution of Minium in Spirit of Vinegar mixed with Snow, excited the frigorifick Quality of it; yet some of that Solution being enclosed in Snow and Salt, would not be froze by them. Snow shut up alone, thawed much more slowly, than that which was mixed with Salts or Spirits. No Salts will promote the frigorifick Quality of Snow, so far as to enable it to freeze, which quicken not its Dissolution. Neither Crystals of Tartar, nor Borax, both beaten to powder, nor Sublimate would enable Snow to freeze, as well as the Powder of each lying undissolved in it. 10. Water of Quicklime being twice tried would not freeze, but only gather a dew on the outside; yet the Liquor being kept up 12 Months the Spirits with which those Waters abound flew away. 11. Oil of Turpentine in which Ice dissolves slower than in several other Liquors enables not Snow to freeze. Tho' Spirit of Wine shut up with Snow in a Bottle, enabled it to freeze powerfully, and to Chrystalize even Urine itself, which might be taken off in Scales. 12. Spirit of Nitre and Snow being mixed together in a just Proportion froze very powerfully and speedily, not only Water but Spirit of Vinegar, and weak Spirit of Salt; the first of which retained its taste, when froze, and the latter shot into Crystals which lay across each other. A Solution of Salarmoniack partly evaporated would shoot into Crystals like combs and feathers, and Salarmoniack distilled from Quicklime would shoot into Branches almost like those, so nimbly, that one's Eye might discern them to spread and increase. The like Experiments being tried with Wine and strong Ale succeeded, but very faintly. 13. Since Bodies generally help Snow to freeze, which hasten its dissolution; we threw into a Vial, which contained Snow, heated Sand, which enabled it to cause a Dew, but not to freeze. And warm Water poured into another, when it had been shaken, produced a considerable degree of Cold, and gathered Dew, but froze it not. 14. Tho' it is generally believed, That the Hoar-froast on Glass-windows, is only exsudations through the Pores of the Glass, and froze by the External Cold; yet it will easily appear, That it is rather on the inside the Glass; the Steams which rove up and down the Room being condensed by the External Cold, and froze. 15. To show, That the Ice which appears on the outside of the Vial in the foregoing Experiments, proceeds not from any subtle Parts of the Mixture penetrating the Pores of the Glass and settling on the outside; we found that four Ounces and ¼ of the Mixture of Ice and Salt, being shut up in a Vial, by the access of Dew on the outside, the weight of it was increased 12 Grains. Another Vial which contained two Ounces six Drams and a half increased in weight 4 Grains; the Vial being unsealed under Water, it sucked in a good quantity of it. Six ounces Snow and Salt being sealed up in a Glass, the Hoar-Frost was wiped off but returned again; and the Vial being counterpoised in a pair of Scales, the Vapours condensed by the coldness of it, in the time that the Snow was melting, weighed 10 Grains. A like quantity of Snow and Spirit of Wine being shut up in a single Vial, the outside was presently covered with Ice, and in all it became 7 Grains heavier than before. Another time a mixture of Snow and Salt, which weighed 3 ¾ ounces, afforded 18 grains of condensed Vapours. And a mixture of Snow and Salgem. which counterpoised 3 ounces and 70 grains, upon an additional weight of condensed Vapours, weighed 20 grains more than before. TITLE II. Experiments and Observations concerning Bodies disposed to be Frozen. Of Bodies disposed to be frozen. WIthout any more than barely intimating, that there are several Bodies disposed to be froze by one degree of Cold, that are not with another; I shall observe, 1. That in very cold snowy Wether, Water, Urine, Beer, Ale, Milk, Vinegar, French and Rhenish Wine, were either totally or partly turned into Ice. But besides these more obvious Instances, we froze a Solution of Sugar, and another of Gum Arabic, in Water; a Solution of Alum, Nitre, and Vinegar, froze without affording any considerable Phaenomena. A Solution of Vitriol was in part froze, and in part unfroze, that which was froze being not much different in colour from Water; but the unfroze part was of a very high Vitriol-colour. 2. Spirit of Urine and Spirit of Vinegar exposed to an intense Fire, both of them froze. 3. A drachm of Salt of Pot-ashes being dissolved in two ounces of Water, presently froze in an intense Cold; and Oil of Tartar per deliquium, or at least, a Solution of the fixed Salt of Tartar was congealed in a mixture of Snow and Salt. Appendix to the II. Title. Oil becomes much more hard in Muscovy than here in England in the most excessive Cold, but will in neither be turned into perfect Ice. And Captain James, speaking of an Island where he and his Men were forced to Winter, Pag. 58, says, All our Sack, Vinegar, Oil, and every Thing else that was liquid, was now frozen as hard as a piece of Wood, and we must cut it with a Hatchet. And Olaus Magnus, Gent. Sept. Hist. l. 11. c. 24, says, speaking of the Fights wont to be made on the Ice in the Northern Regions, Glacialis congressus fit in Laneis calcibus, non pellibus, aut coriis unctis. Vis enim frigoris, quodcunque fit unctuosum, convertit in Lubricitatem glacialem. There being a great similitude betwixt Spirit of Wine and Oil, in respect of their inflammability, and being disposed to mix with oily Bodies, and as great an aptitude in the Spirit of Wine to mix with other Liquors: I enquired of the Russian Emperor's Physician, what alterations he had observed to be produced by Cold in Muscovy? To which he answered, That Aniseed and other weak Spirits would be turned into an imperfect kind of Ice, and that strong ones would turn Ice into a kind of Substance like Oil. Particulars referrable to the II. Title. 1, In a very hard Frost in December, a Solution of Minium near the Fire seemed to be froze; tho' it was made with Spirit of Vinegar, and so strong, that part of it was shot into Saccharum Saturni. Some at the top, which was yellow, did not freeze, tho' poured out. 2. A Solution of Gold made with Salts was likewise froze. As also a Pint-vial full of the Tincture of Lignum Nephriticum, which being froze, the Ice had no such colour as the Tincture. 3. It is reported, That in Russia, Brandy will freeze, but the Ice of it is not so hard as common Ice. And I am informed, that in Moscow the Spirit of Wine would freeze; leaving some dissolved in the middle which was much stronger than ordinary Brandy. And I am told, that in Russia it is usual to have Wine froze. French Brandy being exposed to the Air in Russia froze; and Salad-oil become as hard as Tallow, but Water, at the same time did not freeze. TITLE III. Experiments touching Bodies indisposed to be frozen. Bodies not disposed to freeze. 1. THE subtle parts of several Bodies being brought over by distillation, would not freeze by such an application of Snow and Salt as froze other Bodies. Of this sort were Aquafortis, Spirit of Nitre, of Salt, Oil of Turpentine, and almost all the Chemical Oils we had then in possession; Spirit of Wine, and of other fermented Liquors; and Sack, if good, would scarce freeze; but the inflammable Part being spent by burning, it would easily freeze. 2. Two drachms of Salt of Pot-ashes, being dissolved in an ounce of Water, the mixture would not freeze; tho' the outside of the Vessel was covered with Ice. At another time a strong Solution of Salt of Tartar would not freeze, tho' at the same time Salt of Pot-ashes being dissolved did. 3. That common expressed Oils of Vegetables will freeze after their manner, and curdle in cold Wether, is commonly observed; yet train-oil, which is usually made of the Fat of Whales by the help of Fire, continued fluid in Wether that was very sharp, but in an excessive cold night it lost its fluidity; which seems to disfavour what Olaus Magnus writes, who says, That in the Northern Regions it is usual to cast train-oil upon the Water in their Ditches, to keep the Water from freezing, and thereby unpassable, the Oil, as he says, not being subject to congeal with Cold; but it may be worth while to inquire, Whether the train-oil he speaks of be the same as is used by the Swedes, Laplanders, and Muscovites, and whether they have a different way in keeping of it or not? 4. Tho' a Solution of Sugar would freeze, yet a strong Solution of Sugar of Lead would not in a mixture of Snow and Salt; which is remarkable, since the Spirit of Vinegar itself would freeze: Besides there must needs be some Water in the Solution, and the Sugar being but a Vitriol of Lead, it is not a little strange, that it should not freeze as well as common Vitriol; tho' in this latter concrete, Metal be corroded by a Spirit; which, if we may judge by the Liquor afforded in Distillation, is very much sharper and stronger than Spirit of Vinegar. 5. Quicksilver would not freeze in the sharpest Air, tho' exposed to it in very thin Glasses, and in such a manner, that a little quantity of it made a large Surface. 6. A very sharp Frost was not able to freeze a strong Brine, tho' at the same time other saline Solutions were congealed. But a Solution consisting of twenty Parts of Water and one of Salt, was froze in a very sharp Night; the Ice swimming at the top, in Figures almost like Broom, spreading from the surface of the Water downwards: The Salt dissolved in this Water, is double the proportion of that which is usually in Sea-water. I thawed Ice of Salt-water, to try whether the dissolved Ice would be fresh or not, but it retained a little brackishness, which, I suppose, it received from the contiguous Brine; tho' I am informed, That in Amsterdam they make use of thawed Ice, instead of common fresh Water, in Brewing. And Bartholinus de usu Nivis, Cap. 6. p. 42. says, De Glacie ex marina aqua certum est, si resolvatur, salsum saporem deposuisse, quod etiam non ità pridem expertus est Cl. Jacobus Fincbius Academiae Nostrae Senior, & Physices Professor, benemeritus, in Glaciei frustis è portu nostro allatis. Particulars referrable to the III Title. 1. Spirit of Salarmoniack made with Quicklime, volatile Oil of Amber, a small quantity of Oil of Vitriol, being exposed two Nights and a Day, froze not. A Solution of Silver in Aqua fortis was; and Spr. Sanguinis Humani, being froze, swollen so much as to force out the Cork. 2. Unrectifyed Oil of Turpentine exposed to the Cold in a Bottle would not freeze; but another Portion being contained in an earthen Porringer did. 3. I am informed, That there is a Lake of Water in Scotland, out of which a small River runs, the Water of both which is never froze; but dissolves Snow or Ice if cast into it. 4. Salad-oil being made use of to keep the Locks of Guns from freezing, hindered them from being discharged; but Oil of Hemp, or train-oil kept them from freezing. TITLE IV. Experiments and Observations concerning the degrees of Cold in several Bodies. Of the degrees of Cold in several Bodies. TO discover the different degrees of Cold we have proposed several Thermometers in the preceding Chapters, concerning which we shall add this Advertisement viz. That tho' those which are to be immersed in Liquors, have the Ball end round; yet, when we are to try the degrees of Cold of consistent Powders, it is better to make use of such as have flat Bottoms, that they may be able to stand on their own Basis: For so it will be pleasant to see the suspended Bubble in one of our Thermometers rise and fall, as it is removed from one Body to another. 2. Freezing hath been so generally esteemed, the utmost Effect of Cold, That most have been content, without examining strictly the several degrees of it. Nor indeed is it very easily done, since if we do it with common Weather-glasses it will be a hard thing to distinguish whether the Cold of one Day, exceeds that of another; since there intervening so much time betwixt the Observations, the Alterations may be caused by an increase in the weight of the Atmosphere. And should we make an estimate by the Testimony of our Senses, we should easily be mistaken; since it is believed, That the different sensations of Cold which we perceive, depend on the various Dispositions of our Bodies. But allowing, that vulgar Thermometers might give us a true Information of the degrees of Cold, which Nature affords, yet they acquaint us not whether Art may not produce greater; much less will they help us to make an estimate of this Disparity. And though we may make some guess by the Operation of Cold on Liquors exposed to it, yet some as Aqueous Liquors frieze too soon, and vinous Liquors here in England will not freeze at all, except French Wine; which happens seldom and leaves too great an Interval betwixt the degrees necessary to congeal Wine, and sufficient to freeze Water, besides the uncertainty proceeding from the several strengths of Wines. Wherefore to discover the Intensity of Cold, produced by Art above the highest degree that Nature affords, See Plate. 1. Fig. 1. we furnished a sealed Weatherglass (Such as Plate 1. Fig. 1. Delineates') with Spirit of Wine, and immersed the Ball and part of the Stem in a Vessel of Water, which was half buried in Snow and Salt, and when the Water began to freeze at the bottom and about the sides, the Liquor was Subsided to 5 2/● Divisions, each Division being half an Inch; and then the Weatherglass being taken out of the Water and applied to the Snow and Salt, it Subsided to 1 ½ Division. To this we shall add another which shows, That the Water tho' froze was warmer than the Spirit of Wine, when the Mixture of Snow and Salt was applied to it. Jan. 15 the Weatherglass being kept in the Water till it began to freeze descended to 5 ½ but being removed into the Snow and Salt it Subsided first briskly and then more gradually till it sunk to the Bottom of the Stem; but being removed into the Water again, it ascended to the same height, the Water had before depressed it to. For a further Trial, how much Liquors may be condensed by Cold, we took Oil of Turpentine rectified in a gentle Heat, and having weighed a Glass-ball with a long Stem, it being one Ounce, one Dram, five Grains and a half; we poured on it so much of the Turpentine as increased the weight to, two Ounces seven Drams and thirty four Grains and a half; which reaching a little way into the Stem, we marked the Superficies with a Diamond; after which we poured a Dram more in, and successively more; still marking how high each Parcel, which was weighed exactly, wrought in the Stem, till the Additional weight increased the former to three Ounces, one Dram, four Grains, and a half; and then taking a wide-mouthed Glass with Water in it, we immerged the Weatherglass in the Water as before; the Vessel in which it was contained being first encompassed with Snow and Salt: When the Water began to freeze, we marked the Stem of the Glass which contained the Oil at the place to which it subsided; and then conveying it into a Mixture of Snow and Salt, when it had subsided as low as it could, we marked the Superficies, and then removed it into the Air, till it risen to its first station; and then we poured so much of the Oil out into another Glass carefully poised in a pair of Scales, that the Superficies of the Oil remained at the Mark which it subsided to in the Water; and we found that the Oil poured off weighed about 10 Grains: And so much more being poured off as made it stand at the Mark to which the Snow and Salt depressed it, it weighed about as much as the former; so that the Oil was Artificially condensed, so far, That it subsided as much after it had been condensed by Cold strong enough to freeze Water, as it was caused to fall by the force of that. And by dividing the whole Proportion of Oil, by the number of Grains whose Bulk it seemed to lose by subsiding in Water, we found that it was condensed by the first degree of Cold to a 94th Part of its Bulk and by dividing it by the Additional number of the Grains more, we found that the Snow and Salt had condensed it a 47th Part of its Bulk. Having circumscribed Water moderately Cold with a Mixture of Snow and Salt, what it shrunk was, if not insensible, inconsiderable. To measure the differing weight and Density of the same Proportion of Water, in the Heat of Summer and when extremely Cold; we weighed a Glass-Bubble in it, which was Heavier than Water moderately cool, and by the Diminution of its weight in that Medium; we found, according to the Rules of hydrostatics, the weight of a Portion of Water of equal Bulk: And then weighing it in Water cooled, by a Mixture of Snow and Salt, we were informed by a new Decrement of its weight, of the weight of an equal Bulk of that Cold Water; by which we were enabled to make an Estimate of the Gravity and Density acquired by the Action of Gold, and by weighing the same Bubble in the same Water in hot Wether, we Learned further how much more dense and heavy Water moderately Cold and extremely Cold, is than warm Water. It would be of use to try such Experiments as these in Italy, where they have the Conveniency of keeping Snow, and of freezing warm Water speedily. A Glass-Bubble which in the Air, weighed 150 Grains being weighed in Water; on a Day not frosty, it weighed 29 ●/8 and being weighed in Water which was a little froze in a Mixture of Snow and Ice, it was not above ⅛ Part of a Grain lighter than before; so that the Water by Condensation lost not above a 230th Part of its former Bulk. How far it may be of use at Sea to make such Experiments as these, and whether they may thereby learn to know, by finding the Density of the Water in several Places; what Loads to carry in their ships and what the Water will be able to bear, I shall leave others to Judge: But if such Experiments be tried in several Parts; our Sealed Weather-glasses, or that which contains the Pendulous drop of Water, may be of use; since they not being subject to be varied by the Alterations in the Atmosphere's Gravity, and since they may be conveniently carried from one Country to another, the different degrees of Cold in various Regions may be better Estimated; a Register being kept of the degrees the Liquor or Pendulous drop stood at such times as the Trials were made and where, and when exposed to such a degree as was able to freeze. To conclude this Title I shall add, that in making these Experiments, with the Thermometer in which the Pendulous Water is contained; the Stem may, for conveniency, be held either Horizontal, upwards or Perpendicular. TITLE V Experiments concerning the Tendency of Cold upwards or downwards. What way or in what Line Cold acts most vigorously. THAT Heat generally acts most powererfully on Bodies above it, and that its Tendency is upwards, is self-evident: But to discover in what Line Cold acts most vigorously and furthest, we made the following Experiments. A Glass-Bubble with Water in it, having a flat Bottom, was suspended within less than half an Inch over a Mixture of Ice and Salt, but froze not. A Bottle which contained a Mixture of Snow and Salt being held under Water, it was cased with Ice, especially about the Bottom; so that the Action of Cold seems chief to tend downwards. But I rely less upon this Experiment, because it is observed, That when a frigorifick Mixture is exposed in a Vial, the Ice on the outside is always opposite to the Mixture, not reaching higher or lower than that Mixture, above half the Breadth of a Barleycorn; and as the Mixture dissolves, and that which swims upon the dissolved Part grows less and less, so Proportionably the circle of Ice grows narrower on the outside, till the Mixture is wholly dissolved, and then the Ice vanishes. And from an experiment shortly to be mentioned, viz. Eggs suspended under Water, it appears, That Cold acts on every side, the Shells being wholly incrustated with Ice. To put an end to this Title, I shall, in order to facilitate some Experiments hereafter to be made, advertise, That whereas in common Experiments Water naturally beginning to freeze at the top, and that Ice confining the subjacent Water, so that when froze it hath not room to expand; I say, whereas in such cases the Glasses are subject to break, to prevent such ill Consequences; I lay the frigorifick Mixture first about the bottom of the Glasses, by which means the Water beginning to freeze at the bottom, the Water is raised up above it; and as the Salt and Ice is raised higher about the Glass, so the Ice gradually rises, without danger of breaking the Bottles. To this Advertisement I shall add, That tho' I only at the first lay the mixture about the bottom of the Glass, yet to keep the Water above, cool, I usually put Ice itself or Snow (either of which will succeed in these Experiments) above that Mixture. TITLE VI Experiments and Observations concerning the preservation and destruction of (Eggs, Apples, and other) Bodies by Cold. Of the Preservation of Bodies by Cold. IT is a common Tradition, That if Eggs or Apples be thawed near the Fire, it spoils them; but if they be immersed in cold Water, they thaw slowly without damage. To try the truth of this Tradition, I made the following Experiments. An Egg which weighed 12 drachms and a grain, being wrapped in a waxed Paper to defend it from the thawing Snow, was froze in a mixture of Snow and Salt; and then wanting 4 grains of its former weight, it was put into a Basin of Water: It acquired such a Crust of Ice about it, as increased the weight to 15 drachms and 9 grains; and the Ice being taken off, and the Egg dried, it weighed 12 drachms and 12 grains; being broke we found it almost thawed: When froze it swum in the Water, but when thawed it sunk. We took two Eggs well froze, and placing them both at an equal distance from the Fire, the one was put into Water and the other laid on a Table: When that in the Water was crusted over with Ice, we took it out, and breaking it, found that the Yolk and some part of the White were thawed; but the other Egg being cut asunder, the White was wholly frozen, and the Yolk hard as if it had been overboiled: There likewise appeared in it certain concentrical Circles of different Colours, and a very white Speck in the middle of it. The same Experiment being tried a second time, we were confirmed in our Persuasion, That frozen Eggs will thaw sooner in cold Water, than in the open Air. An Egg being suspended in Water, was covered with a Crust of Ice equally thick on all sides. Frozen Pippins being put into a Basin of Water, were covered over with a Crust of Ice of a considerable thickness; where it was observable, 1. That that Part of the Pippin which was immersed, was covered with a much thicker Crust than that which was above it. 2. The extant Part seemed harder than the immersed. 3. Those in the Water were thawed, but one that lay out of it was much harder and more froze. 4. Neither the frozen Eggs or Apples condensed and froze the Air, tho' they incrustated the Water. Eggs being froze in Snow and Salt till they cracked, we put one into Milk, two into a Glass of Beer, and two more into a large Glass of Sack, but produced no Ice. Eggs being put into Vinegar produced no Ice; but the Vinegar corroded the Eggshells. A Cheese immersed in Water in a cold Country, was crusted over with Ice; but lumps of Iron, pieces of Glass, and Stones, being kept longer in Snow and Salt than was sufficient to freeze Eggs, produced no Ice in Water. Water being poured into a Bottle which stood on the North-East side of our Elaborotory, Part of it was presently turned into Ice. Ice and Juice of Pippins shaken together in a Vial produced a great deal of Dew, and so did Ice beaten into a Liquor with the White of an Egg. Pippins were much better when thawed in cold Water than hastily. It hath been observed in the cold Northern Climates, That when they have come out of extreme Cold too hastily to the Fire, it hath raised Blisters; wherefore it is a custom amongst the more careful sort, to wash their Hands, or other frozen Parts, in cold Water or Snow before they approach the Fire. I am told by one, That Cheeses being froze in Muscovy, those thawed in Water were crusted over with Ice; but were much better than others thawed in a Stove. And Guilielmus Fabritius Hildanus, Cap. 10. de Gangraena & sphacelo, gives an Account of a Man who was successfully thawed and crusted over with Ice as our Apples and Eggs were. Tho' a moderate degree of Cold preserves Bodies from putrefaction; yet Glaciation leaves them more subject to it upon a thaw, tho' whilst they are in that state they putrify not. To prove that the highest degree of Cold under Glaciation hinders Bodies from Corruption, I shall allege the following Instances, Bartholinus de usu nivis, says, p. 80. Regii Mutinenses nivem hoc fine arcte compactam servant, in Cellis Nivariis, in quibus fervente aestate vidi carnes mactatorum Animalium a Putredine diu se conservasse. And Capt. James in his Journal, p. 74. hath these words, By the ninth of May we were come to and got up our five Barrels of Beef and Pork, and had four Butts of Beer and one of Cider— It had lain under Water all the Winter; yet we could not perceive that it was any thing the worse. P. 79. he farther says, That a Cable having lain under Ice all Winter, was not in June found a jot the worse. And from Simlerus his Account of the Alps, it appears, That entire Bodies may be preserved by Snow without Glaciation. Refert (says Bartholinus, speaking of him, p. 79. de figurativis) in Rhetis apud Rinwaldios; nivium è monte ruentium moles Sylvam & proceras Abietes dejecisse, accidisse etiam Helvetio Milite per Alpes iter faciente, ut 60 homines & plures eadem Nivis conglobatione opprimerentur. Hoc igitur Nivium tumulo sepulti ad Tempus aestatis delitescunt, quo soluto nonnihil Nive deciduâ Corpora Mortua inviolata patent; si ab amicis, vel transeuntibus quaerantur. Vidimus ipsi triste hoc Spectaculum, etc. To prove that inanimate Bodies whilst froze are not subject to Putrefaction, I shall bring several Instances. Nor indeed is it much wonder, since, whether Glaciation proceeds from intruding Swarms of frigorifick Atoms, wedged in betwixt the Parts of a Body, or whether we suppose it to arise from an avolition of those restless Particles which before kept the Body fluid or soft; we must suppose an unusual rest, and consequently the concomitant cause of Corruption to be wanting. But to proceed to Instances, I am told, That on the Coast of Sweeden and Denmark, the Cold will preserve Bodies a long time from putrefaction. And Bartholinus relates a Story of several dead Bodies (p. 83. de usu Nivis) which being killed in a Battle in the Winter, were froze in several Postures, and continued so without being corrupted as long as the Winter lasted. To which I shall add, that Capt. James tells us, p. 76. of a Man whom they found froze in the Ice six Weeks after he had been committed to Sea, and all the alteration the Frost had wrought on his Body, was, that his Flesh would move up and down upon his Bones like a Glove upon a Man's Hand. And Bartholinus de usu Nivis, Cap. 12. further tells us, That 'tis observed in Greenland, that the Frost preserves Bodies from Putrefaction 30 Years. But tho' freezing preserves Bodies from Putrefaction for the time, yet when they thaw they presently discover, that the Textures of them were impaired and vitiated all that while by the action of the Cold; for having froze an Ox-Eye, I observed, that the Crystalline humour, which was so transparent before, being froze, lost its diaphaneity and became white. And it hath been observed by others, That tho' Cheeses which were thawed in Water, were better than those that were otherwise freed from the Ice; yet they were all, in some measure, impaired by the Frost. To these Instances I shall add, that Purchas, Lib. 3. Cap. 5. Sect. 2 p. 493. tells us, That in Nova Zembla, their strong Beer being froze, was wholly vitiated, and without strength or taste. And Capt. James tells us, That strong Alicant Wine, by being froze, had lost much of its Spirits. And it hath been observed in the Northern Country, less cold than Muscovy, That Beef having been froze, was almost insipid, and yielded Broth little better than Water. Besides which Instances I am informed, That Bodies much harder than any yet mentioned may be worked upon by Cold; not to mention, that it is observed, That Bones, and even Steel itself, are much more subject to break in frosty Wether than at other times. And it is to our present Purpose, further observable, That Capt. James relates, that in Charlton-Island the Wood must be thawed before the Carpenters are able to work it. And I am further informed, That the Timber of the Houses in Moscow will not only crack in frosty Wether; but 'tis observed, That Brick-Houses in the West-Indies decay much sooner than here in England. And it hath been further observed, That Marbles themselves have not only flown in pieces in frosty Wether, but that Brass-Instruments, and even Iron-Hoops have been cracked by extreme Cold; as Olaus Wormius, and the Dutchmen in their Voyage to Nova Zembla witness. But I am apt to believe, that the breaking of the Iron-Hoops rather depended on the operation of the Cold on the Liquor contained in those Barrels; than immediately on the Iron-Bars themselves, and that they were broke by the expansion of that Liquor. An Appendix to the VI Title. In confirmation of what hath been delivered before, the Russian Emperor's Physician told me, That if those that have their Noses or Cheeks froze, don't rub them with Snow before they go into the Stoves, they sometimes drop off; and he likewise told me, That moderately weak Wine by being froze, would lose both its colour and taste. He further told me, That Bodies there, will keep all the frosty Wether uncorrupt; and that Venison and Beef, and other Flesh, will be preserved a long time by Frost; but if it is not thawed leisurely before it comes to be roasted, it will be much impaired. And I am told, That a young Man having been froze all over, was recovered by being first rubbed with Snow before any other means was used. Particulars referrable to the VI Title. Fishes taken from under the Ice, in Lakes and Ponds which were frozen over, and packed up, would be preserved a Month without being salted or dried; and it was observed, That when they were taken out of the Water in the cold Air, they would be froze immediately. It was likewise observed by the same Person who told me these things, That tho' Flesh-meat froze was better when thawed leisurely in cold Water than hastily by the Fire, yet it acquired not a Crust of Ice about it. In Lapland when any Part is froze, they toast Cheese made of Deer's Milk, and anoint the affected Part with the Cows-body. I had some Cheshire-Cheeses froze myself, one of which being thrown into Water gathered a Crust of Ice about it. There are white Bears in Green-Land which have so excellent a scent, that when the Carcase of a Whale was left at some distance from the shore; they would raise themselves, on their Legs, and with their two Paws, would fan themselves with the Air, and snuff it in at their Snouts, and then throwing themselves into the Sea would Swim towards the dead Carcases; the fat of some of them would yield a Hogshead of Oil. In Moscow a Hogshead of Malaga-Sack being froze, a Spirituous Liquor distilled out of it stronger than the Sack itself; but the Liquor left behind it, was a strengthless Phlegm. A Barrel of Beer being froze on the Coast of Green-Land, the Spirituous Part was contained in the middle. The Spanish and French Wines, that are brought to Moscow betwixt Russia and Poland, are sometimes so frozen by the time they come there; that they are forced to break the Casks, and to transport it in Jars from one place to another, and when they have a mind to thaw it, they put it into another Hogshead, and that being placed in a hole made in Ice or Snow, it thaws leisurely there without being so much impaired as if thawed in a Stove or by the Fire. TITLE VII. Experiments concerning the Expansion of Water, and Aqueous Liquors by freezing. Of the Expansion of Water and other freezing Liquors. THO' it hath been generally allowed, that Water and other Liquors are condensed by Cold; yet from what I shall offer, it will appear, That Ice is not Water condensed but Rarified. For I have not only observed, That Water exposed to be froze in a Bolt-head, would if the frigorifick Mixture inclined it to begin to freeze at the Bottom first, be expanded, so as to rise considerably higher in the Stem, but when that Ice was thawed again will subside. And to this I shall add, That having included Water in a Cylinder, both ends of which were stopped up with Wax, the Cylinder being hung up in the Air, and the Water froze; it was so far expanded, That it forced the Wax out of each end of the Pipe, and formed a Rod of Ice much longer than the Cylinder; from whence it appears, That the breaking of Bottles by Cold rather depends on the Expansion of the Included Liquor, than that the weight of the Air caused that Effect, as some Moderns teach; or that the Internal Liquor being condensed by Cold, the Air breaks in to prevent a Vacuum: For that Water is expanded by Cold, appears from what I have said; besides nothing is more commonly observed, than that Water being froze in a Vessel whose sides are strong enough to keep it from bursting them, the Superficies of the Ice is generally protuberant and convex. And that the breaking of Bottles depends not on Nature's abhorrency of a Vacuum, appears; since should we suppose, That the Fluid contained in a Bottle would be so far condensed as to possess less space than before; it is possible there might be a Vacuum there, and the Bottle not burst; since Glass-Bubbles much thinner than ordinary Bottles will endure the frost, tho' stopped close with Air in them. But not only Water expands itself upon freezing but other Aqueous Bodies; so Eggs being froze, burst their shells asunder. And Milk, Urine, Rhenish Wine, and good Spirit of Wine, being set to freeze in distinct Glass-Eggs; the Wine being froze swelled an Inch above the first Surface, the Milk two Inches, and the Urine six or seven. And a Solution of Dantzick-Vitriol, did not only become Opace, but risen considerably higher in a Cylindrical Pipe, upon Congelation. Whether more stable and consistent Bodies are capable of being expanded by Cold; would be worth enquiring; since it hath been observed, That in Nova Zembla the very Clocks have been froze so that they would not go; and the like hath been observed by Capt. James in his Voyage at Charlton-Island; his Watch being froze as well as his Clocks. Whether these Effects depended on any Swelling of the Ropes, or whether the Spring of his Watch might be weakened by Cold, or whether some Iceicles stuck to the Internal Parts of it; I shall leave as bare Conjectures, to be further examined into by Experience. The Phaenomena of an Experiment about Freezing referrable to the VII Title, read before the Royal Society. Having filled a Bolt-head which was as big as two Turkey Eggs with Water, till it wrought, a pretty height into the slender Stem, being put into a Mixture of Snow and Salt, it subsided a little; but when it began to freeze it would sensibly swell. The Experiment being repeated with a Glass whose Stem was as thin as a Raven's Quill; when first the Ball of it was immersed in the frigorifick Mixture, the Water presently ascended the height of a Barleycorn, and presently subsided again, which the Florentine Virtuosos would attribute to a Constriction of the Glass upon the Application of the frigorifick Mixture. Secondly, And tho' the Florentine Virtuosos, relate, That they have observed, the Water after it had subsided, a little to rest, and then subsided again; yet in all the Trials I made I did not observe it. Thirdly, When the Water had subsided a little, it would be at a stand, till the Liquor began to freeze. Fourthly, The Experiment being tried with Glasses whose Stems were unequally big, upon Glaciation, the Ascent of the Water in the large ones would be indiscernible; but in a slender one it would ascend several Inches in a Minute, till it risen up to the top of the Stem. Fifthly, Tho' the Forentine Academians, say, they have observed the Water to rise again, before Glaciation; yet I could never see such a Phaenomenon. Sixthly, If the Glass was taken out of the Mixture when first it began to freeze, as soon as the small Iceicles were melted, it would subside again; yet if reapplyed to the Mixture a second time, it would freeze in half a Minute. TITLE VIII. Experiments concerning the Contraction of Liquors by Cold. Of the Contraction of Liquors by Cold. 1 THO' the Liquors we have mentioned expand themselves upon an Intense degree of Cold, yet we are not thence to conclude, that all will; since we have found it by experience not only in Spirit of Wine, Aqua fortis, Oil of Turpentine and several other Liquors which would not be brought to freeze; but also in Oil congealed by the vehemence of the Cold. 2. Amongst the several Experiments made of the Efficacy of Cold to condensed Liquors, I shall lay down the following. 3. Spirit of Wine being put into a small Glass-Egg with a slender Stem, in a Mixture of Snow and Salt subsided ¾ of an Inch. 4. Mercury being freed from Air, and placed in a Bold-head in a Mixture of Snow and Salt, subsided 2 Inches. Common Oil placed in the same Mixture subsided till it froze; but if it were immediately thawed near the fire, it would expand itself so much as to rise about the Mark. The Experiment succeeded a second time, and being tried a third time, the Lumps of the congealed Oly would sink in the fluid Oil. Oil of Aniseeds artificially froze subsided considerably in a small Pipe. Empyreumatical Oil of Gaujacum being exposed to the utmost degree of Cold, would not freeze; but evidently subsided. Particulars referrable to the VIII Title. 1. Two sealed Weather-Glasses, the one made of a Tincture of Cochineal in Spirit of Wine; and the other of a blue Tincture of Spirit of Man's Blood and Copper in Spirit of Wine; were immersed in Water till it began to freeze, and then being removed into Oil of Turpentine set in a Mixture of Snow and Salt; we observed, That the Liquor in both Thermometers subsided. Oil of Aniseeds being put into a small Glass with a large Stem, and placed in a frigorifick Mixture made by a Solution of Salarmoniack subsided 3 Inches; the substance of the Oil being turned into a white Concrete, which when it was leisurely dissolved, the fluid Part emitted several Bubbles; and it was further observed in this Concrete, That tho' when thawed it swims upon Water, yet when congealed it will not. TITLE IX. Experiments concerning the Bubble from which the Levity of Ice is supposed to proceed. Of the Levity of Ice and its Cause. 1. IT is usually accounted an Argument of the levity of Ice above Water, that it swims upon it: For tho' the superficies of small Portions of it are not sensibly emergent above the Surface of the Water; yet in Greenland, where huge Rocks of Ice float in the Sea, they are observed to be as high above the Water as the Masts of Ships, which could we suppose to float in an erect Posture, and to be of a prismatical Form, that Part immersed would be nine times as much as that above the Water. As for the Reason why Ice is born up above the surface of the Water so much in Greenland more than in our Climate; besides that the size of those pieces of Ice contributes to the rendering the Observation more remarkable, the Water's expansion in that cold Climate may cause it to be further expanded there than here, and consequently lighter. 2. Pieces of Ice free from Bubbles floated in Spirit of Wine drawn from Brandy, and likewise from Quicklime; and tho' if that Spirit were warmed, it would presently subside, yet as it cooled, the Ice would ascend; nevertheless some part of it being thawed, the Water would subside in a stream through the Spirit. In warm Water the Ice would swim; but in Oil of Turpentine and the rectified Spirit of Wine it would sink like a Stone. 3. A piece of Ice which was clear from Bubbles, for as much as we could discern, and very transparent, would not sink in Water; but another piece, which in a Microscope appeared to be full of Bubbles, was nevertheless transparent, and would float on Water. 4. That the levity and expansion of Ice depends on the number of Bubbles dispersed through it, is unquestionable; but how it comes by those Bubbles is a matter that deserves our Inquiry: And tho' Mr Hobbes attributes it to the Intrusion of some external airy Parts, yet we observed, That Water defended from the Intrusion of external Air, was not without Bubbles, when froze in a Glass hermetically sealed; but being expanded, the numerous Bubbles dispersed through it, gave it a whitish Opacity; and the same Phaenomena were afforded by Ice froze in Metalline Vessels. 5. And that the Ice froze in the hermetically sealed Glass, received not its Bubbles from the Air shut up with it; is reasonable to believe: First, Since the Water must be expanded before it could divide that Air into Bubbles. Secondly, That the Air in the sealed Glass cannot be dispersed through the Ice, and thereby cause it to expand, appears; since oftentimes it is so far compressed by the swelling Ice, that it breaks the Glass, which it would not do, could it be mixed with the Ice and dispersed through the freezing Water. But, Thirdly, Were the expansion of Ice to be attributed to the insinuation of airy Parts, it may be questioned, How, when Liquors begin to freeze at the bottom first, the Air, which is so many times lighter than Water, can dive into the bottom of it, and that too without being seen? Fourthly, If the Bubbles contained in Ice were derived from the external Air depressed through freezing Water, Ice thawed would yield Air enough to fill as much space as the frozen Water possessed more than the thawed Water. 6. That the Bubbles contained in frozen Water are not adequately filled with Air, tho' sometimes the Air that they contain be afforded by those airy Parts dispersed through the Pores of Water; and that they are often generated numerously, notwithstanding a recess of the greatest part of that Air, will appear from the following Experiments. I. Water freed from Bubbles in Vacuo Boyliano, and afterwards conveyed into a frigorifick Mixture expanded not so much as common Water, nor was the Ice near so full of Bubbles. II. Water which had been freed from Bubbles in our Prismatical Engine, being froze, contained few Bubbles, but being thawed and then poured into a Glass-Cylinder, it was powerfully expanded so far as to burst the Glass. III. A Glass-egg with a narrow Stem being filled so far with Water, that the surface of it risen an Inch within the Stem; it was conveyed into a Receiver, and whilst the Air was exhausting, Bubbles risen so plentifully, that the Liquor seemed to boil: Which when it was in a great measure cleared of, we placed it in a mixture of Snow and Salt; and observed, that the expanded Liquor being froze, had risen a great way above its first height. When it was placed in the open Air, of such a temper as made it thaw leisurely, we observed, That the exterior part of the Ice was full of Bubbles: But when that was dissolved, the Ice in the middle was of an unusual Texture; being void of Bubbles and not unlike a frosted piece of Glass, whose aspereties were very thick set: When the Ice was almost thawed, we conveyed the Bubble into the Receiver; but tho' the Air was exhausted, we perceived not that the Ice was sooner melted; but the Water afforded a few Bubbles, and in a little time some few appeared in the Ice. When the Ice was wholly thawed, we took the Glass-Bubble out of the Receiver, and found, That the Water had subsided to its first Mark, if not a little below it; so that the Water when expanded rising three Inches in the Stem, and the weight of the whole Water being but two ounces and a half; the Ice seemed to take up about a twelfth Part more than the unfroze Water. 7. A Cylinder of Water being immersed in a Mixture of Ice and Salt, and that conveyed into a Receiver; we found, That when the Air was exhausted, and the Water in a great measure freed from Bubbles, the surface of it was considerably raised; the Water in the bottom being turned into Ice as far as the Mixture wrought, in which we perceived, besides a few large Bubbles, small ones enough to render it opacous. 8. To show, that the Bubbles perceivable in Ice are not filled with true and springy Air, I shall subjoin the following Experiment. We placed a Glass-egg, which was about as large again as an ordinary Egg, in a mixture of Ice and Salt; the Cavity of it being fiilled with Water, which rising up into the Neck, stood about an Inch above the superficies of the frigorifick Mixture which circumscribed it; the Diameter of the Stem being large enough to receive the end of my Finger. The Particulars afforded by this Experiment were, I. The Water did not sensibly subside before it began to freeze. II. Some part of it began to swell in a quarter of an Hour. III. In an Hour the Liquor risen 4 2/9 Inches, and continued to rise till it was above five Inches ½ when we took it out. iv The frigorifick Mixture being below the surface of the Water, it froze at the bottom first, leaving the top of the Water uncongealed. V. No Bubbles appeared in the Water tho' the Ice was full of them, some being as large as small Pease. VI We poured as much Salad-oil upon the Water, as wrought two Inches in the Stem, and then hermetically sealing the end of it up; the Water subsided a little, but was presently raised again to its former height in the Mixture; about an Inch and a half of the Stem remaining above the Oil filled with Air. VII. The Glass-egg being weighed first in Air, was left in the Water poised with its opposite weight. VIII. Upon the thawing of the Ice, several Bubbles risen which vanished at the top. IX. The Water being thawed, the Aequilibrium continued the same, and subsided to its first Mark and no lower, tho' it had parted with so many Bubbles. X. The Glass being inverted, the sealed end was broke off under Water; upon which some of it being forced up into the Pipe, pressed the contained Air into less room than before. XI. The Water and the Oil possessed the same Places that they did before. XII. The Oil being thrown out, and so much Water put into the Stem as raised the surface as high as it was raised by Glaciation; the Glass weighed 4374 Grains: When filled to the lowest Mark it weighed 4152, and when empty 1032; so that the Water contained betwixt the two Marks, was about the 15th Part of the whole. 10. A large Glass-egg with a proportionable Stem, being so far filled with Water, that it wrought up an Inch into the Stem; the next Day the Water was raised 15 Inches: The whole contained in the Cavity of the Egg being froze; the frozen Water continuing to swell, was raised 4 Inches higher, a few drops running over the top of it; but when the Ice was wholly thawed it subsided again. 11. Another Egg about the same height, being placed in beaten Ice and Salt, the Water risen an Inch in an Hours time, and several Laminae of Ice appeared at the Jointure of the Ball and the Neck; but after an Hour and a quarcer, those disappeared, and the Ball seemed to be filled with white Ice; the Water in the Neck being raised 4 ½ Inches above the first Mark. Several small Bubbles ascended through the Neck till it was wholly thawed, and the white Ice was full of Bubbles. The Experiment being further prosecuted, the Water swelled till some of it ran out at the top of the Tube: Upon which, the top of it being sealed up, we placed it in a warm Room till the Water was quite thawed; so much Air only-remaining above the Water when froze, as in dimensions equalled a small Pea. When the Ice was wholly thawed, the Water subsided to its first Mark, and then the top of the Stem being broke off under Water; so much of it was impelled by the external Air, as, when the Pipe was re-inverted again risen 7 Inches, above the first Mark, and left about an Inch ¼ above it; so that the Air which caused the Water when froze to swell, and which was generated there, took up one Inch and ¼: Which being expanded through the Cavity of the Cylinder, above the surface of the Water when thawed; so far appeared not to be Air, that it wanted a Spring to resist the ingress of the Water. 12. Another time the tip of a sealed Stem being broke under Water, it received 10 Inches and above ½ 13. In the same Bolt-head wherein the greatest condensation of Air was tried, the Water being froze, was raised a Foot above its former station; and then being sealed up, and leisurely thawed; it subsided again to its former Mark: And then the Seal being broke off under Water, so much of that contained in the Basin was forced into the Tube, as fill'd 11 Inches of it; near ⅛ of an Inch of Air being generated in the former part of the Operation. 14. Another time the Water swelling 10 Inches in the same Glass, we broke off the Neb under Water, and it received as much of the external Water; so that in this no Air was generated. 15. The like Experiments being tried with aqueous Liquors; the Neb of one that contained Milk being broke off under Water, it was manifestly impelled by the outward Air. And another being likewise opened under Water which contained Urine, it received about five or six Inches of Water. 16. Another Glass which contained Claret-Wine, being opened under Water, the Water was impelled near an Inch above the Mark; which would not have happened, had the Bubbles been filled with true and permament Air. TITLE X. Experiments about the Measure of the Expansion and the Contraction of Liquors. The expansion and contraction of Liquors measured. TO measure the expansion of the Air, we took a Bolt-head, and poured in so much Water, that it risen a little way into the Stem; which being done, and the number of Ounces it contained set down, to those we successfully added one Ounce after another; marking how high each of them wrought: Which being done, we poured out a convenient quantity, and froze the remaining Water from the bottom upwards, and the Ice that consisted of 82 parts of Water, filled the space of 91 and ½; so that the congealed Water possessed a 9th part of space more than it did before. In another Experiment 55 Parts of Water being froze, were extended to 60 ½; 6 of those remaining unfroze. 2. Another way we took to measure the expansion of Water, was, by marking a Cylindrical Pipe at the superficies of the Water contained in it; which, when it was froze, was raised a tenth part higher than before. Another more exact Cylinder being made use of, we found, that Water froze expanded to about a ninth Part of the space it possessed before. 3. But perhaps this Method of measuring the expansion of freezing Water may suggest a difficulty to those that are acquainted with hydrostatics: since Archimedes hath made it appear, as well as Stevinus, That floating Bodies will so far, and but so far, sink in the Liquor that supports them, till the immersed Part of the Body be equal to a bulk of Water, weighing as much as the whole Body. 4. For Capt. James hath observed Ice to float a great deal above the Water; and the Hollanders in their Voyage to Nova Zembla, take notice of a Hill of Ice which was 16 Fathom above the Water, tho' but 36 below it: And Janus Munkius in his Account of G●…enland, observed, That one that was but 4● Fathom under Water, was 20 above it; whereas according to our Computation of the expansion of Water, the Part under Water ought to be 8 or 9 times as deep as that above it. 5. But to clear this difficulty I have these things to represent; First, That the Ice which we take notice of, floats in fresh Water, but that observed by Navigators, being fresh floats in salt Water; yet this is to be likewise considered, That near the Poles the Seas are not so salt as ours, or those under the Line, and consequently will not be able to bear up the floating Ice so high; except the coldness of that Region recompenses the want of Salt. 6. But besides these Considerations, that which I would chief insist upon for the removal of this difficulty, is, That these huge Piles of Ice are made up of vast Lumps, betwixt which are large Vacuities which are only filled up with Air; so that we are not to judge of their weight by the bulk they appear to be of to the Eye; but by the specific weight incumbent on that part immersed in the Water: For we see in Barges, that sometimes they carry Loads, which consisting of light Matter, may be piled a great height above the Water, without depressing the Vessel so much as heavier Bodies of less bulk, which are more ponderous in Specie; for the greatest part of these floating pieces of Ice, as Bartholinus takes notice, are compiled of store of Snow frozen together. Besides, it is observed, That most of those stupendious Mountains which lay so much above Water below rested on the Ground, so that probably they might have sunk much lower, had the Water been deep enough for them; for Mr. Hudson in his Voyage takes notice, in a Bay that bears his Name, of a piece of Ice sevenscore Fathom deep. 7. Having said thus much of the expansion of Water, it perhaps may be expected, that I should say something of the expansion of aqueous Humours; and also of the degrees of the Condensation of Water and watery Humours: But as for the first, I doubt whether there be any expansion, except of the watery Parts of them; but if it may be of any use to direct us in making an estimate of the different Proportions they contain of Phlegm, or other more spirituous Ingredients; I would not discourage those whose Curiosity shall prevail with them to prosecute such Experiments. And as for the condensation of Water by Cold, tho' perhaps in hotter Climates it may be considerable, yet I have not found it very sensible in all the Trials I have made here. Particulars referrable to the X Title. 1. A Bolt-head whose Stem was 17 Inches above the Water being sealed up, and placed about 9 hours in a frigorifick Mixture, the Water ascended 15 Inches ½ and afterwards ½ of ¼ of an Inch; being neglected for an hour the sealed end was blown off, and the Bottom of the Glass broke in pieces. 2. Water freed from Air in. our Receiver, and sealed up in a round Bolt-head, in which the sealed Apex was about 5 Inches above the Water, afforded an Ice very free from Bubbles, and having stood in a frigorifick Mixture about 2 hours, it was raised 4 Inches and ⅜: The Conical Apex being broke with a noise and a seeming smoke, we found Water unfroze, under the Pipe, and that the Air was condensed to a 20th Part of the space it possessed before. 3. The Globous part of a Glass-Egg 3 Inches Diameter was filled with Water and froze from the Bottom upwards; after it had been Hermetically sealed, it risen 8 ½ Inches, the length of the whole Stem being 10 Inches and a half. But being a second time sealed up and froze with Ice in it, it wrought not 4 Inches above its first station. TITLE XI. Experiments touching the Expansive force of Freezing Water. Of the Expansive force of freezing Water. 1. TO help us to make an estimate of the Expansive force of freezing Water, We filled a Pewter-Bottle full of Water; it being large enough to hold half a Pint: In a frosty Night it cracked the Bottle; and the like success we had with frozen Water in a Pewter-box, such as they keep Salves in. And we found the Expansive force of Frost so strong, That it burst a Bottle, the thinnest part of which was 1/14 of an Inch, and the thickest ●/86: It also broke an Earthen Bottle of Flanders-Metal, the thinnest part of which was as thick as the strongest of the other. 2. To make a more Determinate Estimate of the Expansive force of Frost; we made use of a Brass-Cylinder, to which we adapted a Plugg, which falling a little way within the Cylinder rested upon the edges of it. The length of the Cylinder was about 5 Inches and the breadth 1 ¾ The Experiment made in this Instrument was by filling it full of Water and then laying 56 pound weight upon the top of it: And tho' it was a hard matter to cause the Mixture to freeze; yet we were at the last able to do it, and then we observed, That the Expanded Ice lifted up the one side of the lower so high, that the weight fell down; but at another time it succeeded so well, that the lower was uniformly raised, the breadth of a Barleycorn. Upon a gentle thaw the Superficial Parts being taken out, the Ice appeared full of Bubbles: And in the Morning when it began to melt before the fire, the weight being taken off; several drops of Water, dilated into numerous Bubbles, issued out, like a kind of Froth. 3. Another way we took to measure the Expansive force of Cold, was, by driving a Wooden Plugg so fast into the end of the Brass-Cylinder, That half a hundred weight and a quarter of a hundred, might be suspended at it without pulling it out; yet in two frosty Nights the expanding Water was able to raise it a quarter of an Inch. 4. There is one thing in these Trials deserves to be taken notice of, viz. That the Expansion of Air by Heat being sufficient to make it possess 70 times it's former space; yet the utmost degree, Water by Glaciation will extend itself to, is a ninth: So that the former by Expansion acquires 60 times the space that Water does; taking Mersennus his account of the Air's Expansion to be true, which comes short of what we have shown it capable of being Expanded to. 5. We endeavoured likewise to measure the force of Water's Expansion when congealed, by enclosing it in a Iron-Globe whose Diameter was about 3 Inches, and which had a Female Screw continued from its Cavity to the out side; to which was adapted Male a screw so close, That we were forced to use a Vice to screw it in; but our hopes were frustrated; the Compactness of the metal, as we supposed, keeping the Liquor from freezing. 6. It would be worth while to consider the cause of so powerful an Expansion, since neither the Cartesian nor the Epicurean Doctrine are able to explain this Phaenomenon: For the first only accounting Cold to be a Privation of Heat; and depending upon the recess of those subtle Parts, which he supposes Expansion to depend on; according to him, they should rather continue an Inactive Mass, than retain such a Springyness. And since according to Epicurus, Expansion depends on an Insinuation of frigorifick Atoms, It may well be questioned, how parts of Matter, which have such a free entrance into such Vessels, should not rather find as easy a Passage out again as in, without breaking them? Besides in several Oils and other Liquors which must receive those frigorifick Atoms we perceive not the least Expansion at all; but they are rather condensed. 7. How great the Expansive Force of congealed Wine, Milk, Urine and other Liquors is, I shall leave it to others to inquire, and shall only take notice, That undoubtedly it is considerable; since in the Dutch Voyage to Nova Zembla it was observed, That even Iron-hoops were burst by the forcible Expansion of included Liquors. And in Russia it hath been observed, that tho' Beer and Wine would not burst Wooden Vessels, yet Glass and Stone-Vessels would be often broken Particulars referrable to the XI Title. 1. We took a Brass-Cylinder 2 Inches Diameter, and having put a Bladder with Water tied close up in it, so that upon Expansion it could not get out into the Cavity of the Cylinder; we put a Plugg into it, upon which were placed several weights; which amounted to 120 Pounds, yet the frigorifick Mixture being applied to the Cylinder, the Water expanded raised the Plugg, near half an Inch; and the Experiment being repeated again the next Day the freezing Water raised 130 Pound-weight. 2. An Iron-Barrel 14 Inches long and ⅜ of an Inch in Diameter, whose sides were at the thickest Part 1/16 and at the least ●/16; was filled with Water, and being buried in a Mixture of Ice and Salt 2 hours, it made an obliqne crack in the Barrel Six Inches long; and the Ice being taken out seemed full of Bubbles but very small ones; and the like success we had with another Barrel of a Gun, whose Muzzle and Touchhole were stopped up with Metal; nor had we less success when we buried a Pewter Bottle in a frigorifick Mixture, both the Barrel of the Gun and the Bottle being burst in a quarter of an hour. TITLE XII. Experiments concerning a new way of Estimating the Expansive force of Congelation, and of highly compressing Air without Engines. A new way of Estimating the Expan●…e force of Congelation. HOW far we were able to compress the Air by the Incumbent weight of a Cylinder of Mercury, we have else where shown; but to reduce it to a greater degree of Condensation I made the following Experiments. 1. Having filled a Glass-Egg with Water till it wrought about an Inch into the Stem, we placed it in a Mixture of Snow and Salt, and in a few hours the Surface of the Liquor was raised about 7 Inches; and the Apex of the Stem being sealed up, by a fresh application of Snow and Salt it was raised 8 Inches higher: So that the Air being compressed into the space of an Inch, possessed about nine Parts of ten of what it did before: Whereupon the Stem being inverted and the sealed end opened, the Air which when the Stem was inverted, risen up to the Ice, and separated the unfrozen Water in the Stem from it, powerfully expanding itself; forced out about ten Inches of Water, with Violence and Noise, besides a great number of Bubbles ascended from the Bottom of the Glass to the Top. N. B. when the Air was compressed beyond seven Inches, we several times observed, That the Glass just above the Water on the inside was full of little drops of Dew, which when the Apex was broke off Disappeared. 2. A Vial whose neck was drawn out into a slender Pipe, being filled till it wrought an Inch within the Pipe; in a little time, by the Expansion of the Water, the Air being too much compressed, the head of the Pipe flew off; and the same happened to a round white Glass whose Stem, filled with Air, was about 3 Inches: Nor was the success otherwise when we repeated the Experiment in a large single Vial, whose Stem was four Inches long, and its Basis an Inch broad. 3. An Oval Glass about the size of a Turkeys-egg, with a neck almost Cylindrical, was filled with Water within four Inches and a half, and then a piece of Paper being pasted upon the Stem divided into half Inches and quarters, and the Apex being sealed up by a moderate Heat; the Surface of the Water was raised considerably, but the Oval Part of the Glass being covered with a Mixture of Ice and Snow, the Air was compressed into a 17th Part of the space it possessed before; And the Ball of the Glass bursting afterwards with a considerable Noise, the Ice appeared full of Bubbles, which rendered it white and Opacous. In another Glass whose Ball was larger in proportion to the Stem, the Air was compressed into a 19th Part of its former space before the Glass flew in pieces. 3. And this way of trying how far the Air might be compressed and Water expanded by Cold, we thought least Exceptionable; because the Pores of Glass are more impervious to Air and Water, than some Metalline Vessels; for having broken open the Apex of the Stem of one of our Glass-Eggs, we found, that tho' the Water was but a little expanded; yet not finding a way out at the Pores of the Glass, the Water risen up a quarter of an Inch. TITLE XIII. Experiments and Observations concerning the Sphere of Activity of Cold. Of the Sphere of Activity of Cold. IN estimating the Sphere of Activity of Cold, we are not only to consider the Degree of it in the cold Body; but also the Medium through which it is to pass, and the Consistence and Texture of it; as likewise the Instruments employed to receive or acquaint us with the Action of Cold: Since, from what hath been before laid down, it appears, That Weather-glasses give us a more nice account of the Degrees of it; and that our Sensories may mis-inform us, upon the account of their various Predispositions. Besides the Sphere of Activity may be varied by the Bulk of the cold Body. 1. But to consider the Sphere of Activity of small Pieces of Ice; we have found it very small in comparison of the Atmospheres of odorous Bodies; insomuch that I am persuaded, we can have no sense of Cold, without the immediate Contact of a cold Body; since Ice approaching our Sensory, or a Weatherglass, affects neither; tho' held as near as possibly they may without touching. And the like hath been observed at Sea, where in foggy Nights the Seamen have not been able to discern neighbouring Mountains of Ice: Tho' by a Merchant who made the Observation in Greenland, I am told, That he perceived a manifest access of Cold, upon the approach of a floating piece of Ice. 2. And I am told, that in Ispahan the Capital City of Persia, the Ice being never much more than a Finger thick, they usually pour Water upon it, which as it runs over the Ice, is in part froze, by which means, they thicken the Ice, and preserve it in proper Conservatories. This Experiment having been tried in England, by pumping of Water upon Flakes of Ice; I found, That the Pump-water, being warmer than the Ice, thawed it, instead of increasing the Thickness of it. And tho' here in England, Water poured upon Snow promotes its Dissolution, yet in Russia and Muscovy I am told, That Water thrown upon Snow freezes it; which they therefore make use of to incrustate several Bodies with Ice; yet one thing is to be observed, that generally at the same time, the sharpness of the Air is so violent, as to incrustate several Bodies with Ice, when only Water is made use of; so that in trying such Experiments, we are to consider the Temperature of the Air at the same time, which hath a great Influence in promoting or varying the Effects of such Trials. 3. How deep Frost penetrates into Water and Earth will be a very hard thing to determine; since Earth especially, may be more or less disposed to freeze, according to the several Degrees of Cold, and its Duration; the Tex●●●… of the Earth, and the Nature of the Juices d●●●…ed through it, or subterraneal Steams: Whence large Tracts of Land that lie over some Mines, are always free from Snow, good quantities of Limestone being near the Surface of the Earth. 4. But tho' it be so difficult to know to what Depth Frost will reach, yet that we may contribute as much as we can to the general History of Cold, we shall add the following Notes. After four Nights hard Frost the Ground in the Orchard was froze about 3 Inches deep, and in the Garden about 2; after ten Night's Frost, the Ground in the Garden was froze about 6 Inches ½, and that in the Orchard was froze 8 ½ or more. Eight Days after, it was froze about a Foot Deep. 5. A Pipe of Glass 18 Inches long being thrust down into a Hole in the Ground, the Surface of the Water contained in it being level with the Earth; the next Morning the whole Capacity of the Cylinder was froze 3 Inches, from which Stick of Ice a Part of the Cylinder was froze 6 Inches deep; but the rest of the Water remained unfroze: The Ground in the Garden, that Night was froze ten Inches deep. 6. It hath been observed, that in Moscow the Ground in a Garden was not froze above two Foot deep; but Capt. James says in Charlton-Island he observed the Ground froze ten Foot deep; and the same Author in his Journal, p. 86. says, That the Water does not freeze naturally above six Feet. One Particular referrable to the XIII Title: I am told, That a Lee-ward of great Banks of Ice, they may discover them by the access of Cold, twenty Leagues. TITLE XIV. Experiments concerning the Different Mediums through which Cold may be diffused. Of the Mediums through which Cold may be diffused. IN trying these Experiments we are to take Notice, that the Mediums are not to be too thick; since, from Experiments already delivered it appears, That a compact Medium very thick will not give way to Cold. 1. Having placed a Mixture of Snow and Salt in a Pipkin, and another in a white Basin glazed within and without, they were both incrustated with Ice. And that Cold will penetrate Pewter-Bottles, appears from Experiments already laid down. 2. Having caused two Cups to be made of Latin, or Plates of Iron covered over with Tin, the Convex Part of one of which, was less than the Concave of the other; and the less having a broad Ledge, by the help of which it rested on the Brim of the other, so as to leave an Interval betwixt its Convex Superficies and the Concave of the other; we filled that Interval with Water, and putting a Mixture of Ice and Salt within the less Cup, and on the outside of the other, we had Cups of Ice made of the enclosed Water. 2. The Learned Erasmus Bartholinus in his discourse De figura Nivis mentions an Experiment by which Air is turned into Water in the midst of Heat, viz. Ice or Snow being put into a a funnel; which he supposes refrigerateth and condenses the Ambient Air; but I rather think, That the Dew which he supposes to be condensed Air, is made up of moist Vapours swimming in it; which is so small in Quantity, That having suspended a Tunnel in the Air, with a Mixture of Snow and Salt; which is much more refrigerating than either Ice or Snow by themselves, it gathered but a very small Quantity, and that too lasted no longer than whilst the Mixture was dissolving; besides those condensed Vapours were first Froze before they dropped down in the form of Water. 3. That in Hermetically sealed Glasses, a Mixture of Snow and Salt will freeze Vapours on the outside, is evident, from what hath been laid down; but that Cold should not only penetrate Glass, but afterwards act upon Water in Vacuo; was a little more strange: For having suspended a Tube of Water in Vacuo and piled Snow and Ice about it, as high as the Included Water wrought; it worked upon it, and Froze it from the top to the bottom. 4. But what is yet more strange is, That Cold will act through a evidently hot Medium; for drinking a good quantity of Mineral Water's timely in the Morning, I observed a Manifest Coldness through the Muscles of my Abdomen, which was in a higher degree remarkable in a Gentleman who drunk much greater quantities. 5. To try whether the fluidity of Water depended on a Congenite motion in the Parts of it, or whether it was conveyed to it by impulse from the Ambient Air; we provided a Glass-Bubble about the size of a Walnut and of a Pear like shape, whose Stem was purposely made crooked, and suspending it by a thread in Oil of Turpentine contained in a narrow Glass; and this being placed in a Mixture of Snow and Salt, tho' the Oil continued fluid; yet the Water in the Bubble was froze. And when we went to take it out, the Bubble being cracked, the greatest Part subsided to the Bottom of the Mixture; but we perceived, That, that which was pulled out, was divided by a line through the middle from the top downwards. And it was further observable in this Trial, That the two separable Pieces of Ice, being left in a Mixture of Ice and Salt for 14 hours, were very little wasted. The like success we had with a Bubble of Water suspended in Spirit of Wine; but another suspended in Sea-Salt was not froze at all; nor was another that we hung in a sharp brine: But the same Experiments being tried another time; the Water was froze both in the Bubble suspended in Spirit of Wine, and in that which was immersed in the strong Brine; the Bottle which contained the latter being cracked, which cracks were not much unlike the lines drawn from the Pole of a Globe to the Meridian; reaching from the top of the Bubble downwards. 6. A Bubble suspended with Water in it, in a Glass immersed in Snow and Salt, was froze, without the Intervention of any Liquor. TITLE XV. Experiments and Observations concerning Ice. Concerning Ice. 1. THO' in the East-Indies it hath been thought strange, That Water in England should without any Artificial means be turned into a consistent Body; yet it is related by some, That in Russia the Ice on the contrary, is found much harder than Ours. 2. To make an Estimate of the Cohesion of the Parts of Ice, we thought to have tried what weight Cylindrical pieces of Ice of different Diameters would bear: But being frustrated in such Trials, we tried how much weight a Plate of it placed betwixt two Iron-Bars would bear; but having not convenient weights we were forced to be content to know, That it bore a much greater weight than one could suppose it capable of. 3. A piece of Ice 3 Inches long, and as many broad; and about 4 of an Inch thick was laid cross a frame; and a piece of Iron of this Figure (7) having a scale hung at the longer Leg, the Horizontal Leg was placed upon the middle of the Ice; and then 117 Ounces Troy-weight being put into the Scale, when the Iron had melted half the Ice through on one side, and a third Part of the other, the weight was able to break it. The Experiment being repeated when the piece of Ice was 2 Inches and a half long, it bore 17 pound Averdupois and 48 Ounces Troy-weight, when the Iron on one side had melted ⅔ and on the other ½ Parts of the thickness of it. 4. Plates of Ice being laid upon a stool, and Bay-salt strewed on some Parts of them, they promoted the melting of the Ice so much, That they buried themselves in it; but the Parts thawed by this means, were so incorporated with, and froze to the stool, That we could not separate them without knocking them in pieces: At another time Salt thrown upon Ice made a crackling Noise and by a Candle-light, several Steams were observed to rise from them, like from some hot Liquors: A few drops of Aquafortis dropped upon Plates of Ice, and Oil of Vitriol, the latter sooner penetrated but the former with more Noise as if the Ice were cracked. 5. Olaus Magnus Gent. Septentr. Hist. Lib. 1. Cap. 14 says, of the strength of Ice, Glacies primae & mediae byemis ad●ò fortis & tenax est ut spissitudine seu densitate duorum digitorum sufferat hominem ambulantem, trium verò digitorum Equestrem Armatum; unius palmae & dimidiae, turmas vel exercitus militares; trium vel quatuor palmarum integram Legionem vel myriadem Populorum quemadmodùm inferius de bellis hyemalibus memorandum erit. But this account is the less satisfactory; because he tells us not how far distant from the shore this weight would be born, for the weight of one Man may be much greater at some distance from the shore than of more, upon or near the side; since the shore hath there a greater strength to support it. 6. Purchas Lib. 4. Cap. 13 says, That the Ice in Russia was as hard as a Rock; and it is observed by the same, Lib. 4. Cap. 13. p. 813, That the Ice which floats in the Sea being taken up and thawed yields fresh Water; but whether it consists of an accumulation of fresh Particles in the Sea, or whether it is a Collection of Ice carried thither from some fresh Water I much Question; since the main Ocean is seldom froze, and especially since Purchas Lib. 3. Cap. 7. says, That the floating Ice near Nova Zembla which closes up the strait of Weigals flows down from the Rivers Oby and Jenesre and several others. 7. As for the bigness of some Pieces of Ice they seem almost Incredible; the Dutch in their Voyage to Nova Zembla take notice of one 96 foot high; and Capt. James hath met with some as deep under Water, besides what floated above, and some much higher: And Purchas Lib. 4. Cap. 18. p. 837. Tells us of a Mountain of Ice which was 140 fathom high. As for the Length of these pieces of Ice, all that I can meet with is an observation of Capt. James' who measured a piece of Ice which was 1000 paces long. 8. As for the bigness of concrete Pieces of Ice, Mr. Hall in his Voyage to Greenland takes notice of one 24 Miles long. And by another, a vast Tract of Ice hath been observed, which was so long that the Bounds of it could not be discovered from an indifferent high Hill. To which we may add what the French Hydrographer Fournier relates in his Passage to Canada, That he met with some Pieces of Ice as big as Mountains; others, as Ships; and one 80 Leagues long; in some Places plain, and in others unequal with high Mountains. And Olaus Magnus, Lib. 3. Cap. 2. pag. 384. says, Neque minori bellandi impetu Sueci & Gothi super aperta Glacie, quam in ipsa solidissima Terra confligunt: Imò ut prius dictum est, ubi antea aestivo tempore, acerrima commissa sunt Bella navalia, iisdem in locis Glacie concretâ, Aciebus militari modo constructis, Bombardis ordinatis, habentur horrendi conflictus, adeò solida Glacies est in Equestribus Turmis sufferendis, ampliter vel strictè collocatis. And it is known to us all, that not long since, the King of Sweedland and his whole Army marched over the Sea to Zeeland, where Copenhagen the Capital City of Denmark stands. And Bartholinus, de Nivis usu, takes notice, That in the Eastern Regions the Sea hath been froze a considerable Depth. To which I shall subjoin that Glycas apud Fournier, Lib. 9 Cap. 19 observes, That in the Year 775, the Mediterranean was froze for 50 Leagues, 30 Cubits thick, upon which as much Snow fell as raised it 30 Cubits above the Top of the Water. 9 To what Instances we have already recited, we shall add that of the Dutchmen in their Voyage, viz. that some pieces of Ice which were 18 Fathom below Water and ten above, were very blue; the like to which Capt. James takes notice of; and Virgil, speaking of the Frigid Zone, says, Caerulea glacie concreta, atque imbribus Atris. 10. In the Spring the Ice is observed by Olaus Magnus to be much less compact than in the Winter; and it is attested by the same, and also by Mr. James Hall in his Voyages, that when these Rocks of Ice break they make a vast Noise; and the like hath been observed by others: And tho' Olaus Magnus' attributes the cleaving of these Rocks of Ice, to the Effect which warm Exhalations have upon them; yet I am told, that sometimes they are observed to fly in pieces upon excessive Cold. Particulars referrable to the XV Title. 1. A Decoction of Sage, Rosemary and Parsley being exposed to be froze in distinct Vessels, the Superficies of the former was very rough. Juice of Lemons froze, represented Trees without Leaves. 2. Hard Ice beaten, and common Salt being mixed together, afforded white Fumes like Smoke, tho' the Experiment was tried in a close Room. Snow-Water froze in Ice and Salt, afforded an Ice very transparent, and with minute Bubbles. 3. Ice partly powdered, and in part grossly beaten, being mixed with Bay-salt, when the Mixture was stirred, afforded a sensible Smoke, which was greater or less as the Mixture was more or less stirred; and floating over the Brim of the Vessel, rather sunk than risen; just as the Fumes do from a Cloth dipped in Aq. fortis and hung up to dry. 4. I am told by one who was in the Frigid Zone, that he supplied himself with fresh Water from the Ice, by digging Pits in it; and the same Person tells me, That he hath observed Pieces of Ice 50 Fathom deep, which were not above a tenth Part above Water. He likewise observed near the Coast of Greenland, the Variation of the Compass to be 22 Degrees; and a little time after scarce any thing at all. He told me further, That sailing in the Main Sea in the Height of 77 Degrees, his Ship was surrounded with Ice till the 7th of June; and the Ice opening he failed through it; Part of it passing along towards Hudson's straits. And it is observed, That these Mountains of Ice much weaken the strength of Winds, insomuch that if they be driven near them by a Storm, the Wind is so much quashed that they immediately find a Calm. TITLE XVI. Experiments and Observations concerning the Duration of Ice and Snow, and the destroying of them by the Air and several Liquors. What Liquors soon dissolve Ice and Snow. TO discover what Liquors Ice would be soon dissolved in, we contrived to freeze Water in a long Cylinder; which being loosened by applying a warm Hand, we divided some into Pieces ¼ of an Inch long, and others into Inches, and our Experiments being made with these Cylindrical Pieces of Ice: In the first Trial. 1. In Oil of Vitriol, a Cylindrical Piece of Ice of an Inch in length lasted 5 Minutes. 2. In Spirit of Wine 12 Minutes. 3. In Aqua fortis 12 ½. 4. In Water 12 Minutes. 5. In Oil of Turpentine about 44 Minutes. 6. In Air 64 Minutes. The second Trial. 1. In Oil of Vitriol an Inch of Cylindrical Ice lasted undissolved 3 Minutes. 2. In Spirit of Wine 13 Minutes. 3. In Water 26 Minutes. 4. In Oil of Turpentine 47 Minutes. 5. In Salad-oil 52 Minutes. 6. In Air 152 Minutes. 2. We likewise thought it worth while to try, what difference there would be in the Duration of Pieces of Ice, of the same Bulk and Figure, but of different Liquors; as also whether Attrition would contribute to the Dissolution of Ice, which Iobserved it did: Whence it appears, That as the Agents contiguous to Ice are different, they dissolve its Texture sooner or later, and if Snow or Ice be kept in a Place where neither the Sun nor the Air hath much Influence upon it, it will continue a long time. An Appendix to the XVI Title. 1. In confirmation of what was said in the Close of this Title, I shall add the following Account of the Italian Conservatories, sent me by my ingenious Friend Mr. J. Evelyn: The Snow-Pits in Italy, etc. are sunk in the most solitary and cooled Places, commonly at the Foot of some Mountain or elevated Ground, which may best protect them from the Meridional or Occidental Sun; 25 Foot wide at the Orifice, and about 50 deep, is esteemed a competent Proportion. And though this be excavated in a Conical Form, yet it is made flat at the Bottom, or Point. The Sides of the Pit are so joyced, that Board's may be nailed upon them very closely jointed. About a Yard from the Bottom, is fixed a strong Frame or Tresle, upon which lies a wooden Grate; the Top or Cover is double thatched, with Reed or Straw, upon a copped Frame or Roof; in one of the sides whereof is a narrow Door-case, hipped on like the Top of the Dormer, and thatched— To Conserve Snow. They lay clean Straw upon the Grate or Wattle, so as to keep the Snow from running through, whilst they beat it to a hard Cake of an icy Consistence, which is near one Foot thick; upon this they make a layer of Straw, and then Snow, and Straw again; and continue S.S.S. till the Pit is full, and then laying Straw or Reeds upon all, they keep the Door locked. This Grate is so contrived, that the Snow melting by any Accident in laying, or extraordinary Season of Wether, it may drain away from the Mass, and sink without stagnating upon it, which would accelerate the Dissolution; and therefore the Bottom is but very slightly steened, etc. 2. And it hath been observed by the Dutchmen in their Voyage to Nova Zembla, That in June, the Sun was not powerful enough to melt Snow: And even in warmer Climates, where the Reflection of the Sunbeams is not so considerable, Snow continues unthawed all Summer; as upon the Top of the Alps, and other high Mountains. And Capt. James observes, that, in August, Ice that was kept in the Sunbeams, continued unmelted 8 Days or more; and the same Author observes, that the very Ground was frozen in June. TITLE XVII. Considerations and Experiments concerning the Primum frigidum. Of the Primum Frigidum. 1. THO several Sects of Philosophers have disputed about a Primum Frigidum, some contending for Earth, others Water, others Air, and another Sect for Nitre; yet I am apt to believe, That there is no such thing as a Primum Frigidum, or 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, in which that Quality principally resides, and from whence all other Bodies derive theirs; no more than that there is a 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉, or Principle subject of Residence for any other Quality: For if an intense Degree of Motion amongst the minute Parts of a Body, be sufficient to give it the Quality of Heat; it may be enough to render a Body cold, that that Motion is diminished upon a removal of its Cause; so that it may be doubted whether Cold be a positive or a privative Quality. The Earth not the Primum Frigidum 2. Indeed Plutarch supposes the Earth to be the Summum Frigidum: But we daily see, That it is froze by the contiguous Air communicating Cold to it, and, by the Interposition of another Body, may easily be preserved from that. So the Salt-Works upon the Marshes of the Island Xaintonge in France, are preserved from the Damage the Frost would do them, by letting in Water, by Sluices, to overflow them. Besides, were the Earth the Summum Frigidum, it might justly be wondered, why it congeals not the Water contiguous to it, sooner than Hail or Snow in the Air? Since Terrene Parts of Matter cannot be brought thither without some Cause able to elevate them, and perhaps to alter the Qualities of them. Not to mention those Vulcano's which argue the Earth to abound with Subterraneal Fires; and that in several Places where there are no such Vulcano's, as in deep Mines, those that work there, find it very hot and troublesome: And in deep Wells, it is observed, that the Water is so far from being froze, that it comes up reaking hot; which cannot be supposed to proceed from the Beams of the Sun, since it hath been observed by Monsieur de Claves, Livre 11. Chap. 8. That in the Southern Countries the Heat of the Sun penetrates not above six or seven Foot deep. And the subterraneal Parts are so far from being extremely Cold, That it is observed by Miners, That the lower they dig, the more Vapours, exhalations and Heat they find. And Jo. Baptista Morinus, witnesses, That in Mines in Hungary four hundred fathom deep, after the descent of 80 fathom, it is always hot; but whether these may proceed from Subterraneal Fires or a Mixture of other Bodies I shall not determine; since I have seen Bodies actually Cold mixed together produce Heat. And I am told, That in some Parts of England they dig up a Mineral, which, upon a Addition of Water only, becomes Hot; and for a like reason perhaps those Heats in the Hungarian Mines may be caused: For that Mineral Steams ascend, is evident, since they have been observed in a Perpendicular Groave not only to stink●, but by their Corrosive Qualities, to corrode the wooden Ladders. And Morinus himself tells us, That descending into the Golden Mines at Cremnitz, the Heat increased extremely as he descended; which they attributed to a Mine of Smaragdine Vitriol, which lay under it; of which kind of Vitriol, there is some, even in the Cold and Superficial Region of the Earth. 3. But if against what hath been said it should be alleged, That by the Primum Frigidum they only mean some Earth Mixed with the common Parts of the Terrestrial Globe, I should be glad to know, how we must discover this. But tho' I have brought these Arguments against this common received Notion; I cannot agree with Gassendus, who thinks, that the Earth is no more Cold than Hot: Since it being naturally a Body whose Parts are inclined to rest; it, without the assistance of some Extrinsic Agent to put its Parts in Motion, must consequently affect our Sensory with a greater degree of Coldness, than Air or Water, whose Parts are more Agitated. 4. And if those that argue for the Earth's being the Primum Frigidum, had only urged that it was the Summum Frigidum, Earth the Summum Frigidum. I could have more easily agreed with them: Since, in the Straits of Weigats, the Seas are froze; but not in the Northern Seas, nor that of Tartary; for the main Seas never freeze, but only near the Land, where it is much Colder than in the Ocean. Water not the Primum Frigidum. 5. It is the Opinion of Aristotle, and the Schools, That Water is the Primum Frigidum; but in all Waters that are Froze by Cold we always see, they begin at the top, where the Air is Contiguous; which argues the Air Colder than the Water, since it congeals it: Whereas if Water was the Coldest Body, it ought always Naturally to be Froze, or to begin to freeze, rather in the middle than at the top, and rather in the main Ocean than in Gulfs, Straits and small Rivers: For it is observed, That those vast heaps of Ice that float in the Sea, and which we have so often mentioned, depend not on the Penetration of Cold to that depth they sometime sink to; but vast pieces of Ice being gathered together from the shore and small Rivers, and cemented together, depress each other by their own weight; upon which, the falling Snow, gradually increases their Bulk. 6. But tho' I am far from taking Water to be the Primum Frigidum; yet I cannot agree with Gassendus, who thinks it indifferent as to Heat and Cold: For except where some adventitious cause Concurs, the Parts of Water being less Agitated than the Humours about our Sensory, by it, we must adjudge it Cold. And tho' by the Heat of the Sun the superficial Parts of the Water are a little warmer; yet all Divers Unanimously agree, That it is Colder, at the depth of a few Fathoms. Besides it is observed in warm Regions to be much warmer at Land than Sea, and those Countries that lie near the Sea are generally cooler. But as Cold as it is there, they don't find, That it is able to congeal the Water, tho' at the top it is often Froze. Air not the Primum Frigidum 7. By the Stoics and many of the modern Philosophers, the Air is looked upon to be the Primum Frigidum. Yet considering how great a Part of it lies under the Torrid Zone, and that it is for the most Part very Hot, and likewise, that Water enclosed in a Mixture of Snow and Salt will freeze at the bottom and not where it is contiguous to the Air; I say, considering these things, it will appear, That the Air is so far from being the Primum Frigidum, That it is not the Summum Frigidum. Besides Air condensed to the utmost degree it was possible by the Coldness of the Air; and shut up in a convenient Glass, hath been condensed further by the Application of other Bodies: Whence it appears, that the Coldness of the Air depends on the Mixture of some frigorifick Corpuscles with it, and not on the Specific Texture of its own Parts. Besides, Water may be Froze when enclosed in Substances not apt to freeze, and when the Air is not Contiguous to it. Nitre not the Grand Efficient of Cold. 8. The next Opinion I shall consider is, That of the learned Gassendus, who ascribes the frigorifick Virtue of Bodies to the admixture of Nitre: But tho' I allow Nitre to be a substance dispersed through most Bodies; yet, since Cold is only a Privative Quality and an absence of Heat; there are other Agents, which, by stopping the motion of the Insensible Parts of a Body, may deprive it of its power of Heating. Besides, it must be a prodigious Quantity of Nitre, That would be able to render every Part of the Sea so Cold as it is found to be; rot to mention, That Nitre is scarce ever found so deep in the Earth as some Seas extend; besides the Seas afford us very little Salt-Petre, but a great deal of common Salt. 9 And tho' Gassendus asserts, That Bodies receive the Impressions of Cold, from Nitrous Exhalations swimming in the Air; yet amongst all the Experiments I have made, to resolve Nitre into Vapours, I have not found, that it was able to effect more in the Production of Cold, than other Saline Bodies. And Spirit of Nitre is so far from having an actual Coldness greater than other Bodies, That it is potentially Hot. And whether the Exhalations of Nitre will congeal Water or not; Spirit of Nitre, I have observed, will dissolve Ice, as soon almost as Spirit of Wine: And tho' Nitre mixed with Snow or Ice may promote Congelation; yet it proves not that the Parts of Nitre are frigorifick; since the Experiment will succeed with Spirit of Wine. 10. Having said, thus much of Gassendus his Opinion, we shall in the next place, propose some Experiments; which will be a further Confirmation of what we have been saying. 11. Rock-Petre and Ice, being put into a Bottle, congealed the Vapours on the outside; but pieces of Salt-Petre laid upon Plates of Ice dissolved it. Water being satiated with Salt-Petre, and exposed to the Cold in a Bottle, broke it; several Crystals of Salt-Petre having shot in the Bottom of it. From these Experiments it appears, That there are Colder Bodies than Salt-Petre, and that it dissolves Ice, and it is rather Hot than Cold in respect of Ice. 12. On a windy and a cloudy Day, having suspended a Weatherglass in Water satiated with Salt-Petre we observed, That when it had stood a considerable time, and was raised by the string up into the Air, the Liquor contained in it was raised about 2 divisions; and being again immersed in the solution of Nitre, it was presently raised; so that the Air was Colder, than the solution of Nitre. 13. But to conclude this Title; tho' I am far from thinking Nitre to be the Summum Frigidum; yet I doubt not, but that Parts of it rising from the Earth in the form of Vapours, may contribute to the refrigeration of the Air. Not but that there are several other Bodies in the Bowels of the Earth, whose Effluvia being mixed with the Air and dispersed through it, may cool the Air according to their Proportions, as much as Nitre: Besides, since common, Salt co-operates with Snow in the Production of Ice as well as Salt-Petre, and according to Democritus, hath Parts of a Cubical figure, which he assigns to Cold Atoms: And since Gassendus observes, That Salt-Petre consists of Parts not altogether so apt for the production of Cold; these Figures being not Pyramidal but Prismatical; I say, since these Circumstances all concur, I see no reason, why common Salt may not be numbered amongst those Bodies, that are apt to produce Cold. 14. Nay, sometimes it may happen, That more violent degrees of Cold may be caused by a like Coalition of several sorts of Salts. So the Coldness of Snow is advanced by a Mixture of Nitre or common Salt, or other appropriated Additaments. But I must confess, That it is a doubt with me, whether Cold depends on any such saline Exhalations, or the Effects of frigorifick Atoms; but to pass by this Scruple at present without any further Notice: I shall add, that what I have said upon this Title is not so much to confute what Opinions I have mentioned, as to show, that they are Doubtful. One Particular referrable to the XVII. Title. I am told by the Russian Emperor's Physician, That in the Northern Province of Russia; the Earth is thawed but the depth of two foot, and yet good Corn grows upon it. TITLE XVIII. Experiments and Observations touching the Coldness and Temperature of the Air. Of the temper of the Air. 1. THO' Gassendus and several others assert, That the Air is Indifferent as to Cold and Heat; yet since Cold is only a Relative Quality, and since the Parts of the Air, are of themselves in a less degree of Agitation, than the Humours about our Sensory; I see no reason why it should not be esteemed Cold: For notwithstanding it may acquire a considerable degree of Heat by the adventitious Effects of the Sunbeams, or fire; yet we see, that it naturally tends to coolness itself again. And as for the Coldness of the Air, tho' I deny not but that frigorifick Atoms may be mixed with it; yet I judge them not absolutely or altogether requisite to the Production of Cold; since a bare Diminution of the motion of its Parts, is sufficient to produce such a Quality in higher or more remiss degrees. 2. But the Principal intent of this Section being to produce Experiments and Observations; I shall begin with the former. A sealed Weatherglass with Spirit of Wine in it, being enclosed in a Cylindrical Receiver, when the Air in the Receiver was exhausted, it subsided the length of a Barleycorn; but risen again when the Air was let in again; which Effects I attributed to the Expansion of the Included Air, when the External was drawn out. When the Air was drawn out of the Receiver, hot Bodies Externally applied, affected not the Weatherglass; but when the Air was let in again they caused the Spirit to rise sensibly. 3. To measure the Condensation of the Air by Cold, we made the following Experiments. And, First we enclosed Air in Weather-glasses hermetically sealed; which, when it was artificially or naturally refrigerated, and the Apex of the Weatherglass broke open, we could not discern, by the Water it received, that it was condensed above a 30th Part of its former dimensions. A Glass-egg being inverted into Salt Water, in a Cold Night, the Air was so far condensed in it, That the Water risen five Inches in the Stem. And Jan. 29 the Air extended into 2057 Spaces was in a frosty Night contracted to 1965 Spaces. So that the greatest degree of Condensation we could observe was a 22 Part and a little above a third. But a Mixture of Snow and Salt being applied to the Elliptical Part of the Glass, the Water risen 4 Inches higher than in the former Experiment; and the Air was contracted from 1965 Spaces to 1860; so that the Artificial Cold contracted is more in respect of the Contraction, which the natural Cold produced, than That Condensation was in Proportion to its natural temper or rather a moderate degree of Coldness. 4. But to proceed to Observations: Cold may hinder the Operation of the Sun upon the Air in the middle of Summer; and I am told, That it hath been observed to Snow in Greenland all Midsummer Night, and in the Northern Parts of Muscovy it hath been observed, That severe Frosts happened in the close of August. And further, Capt. Weymouth says, That in the midst of Summer, when they sailed not near the Latitude of Nova Zembla, their very sails and Tackling were froze: To which we shall add, that the English when they were sailing to Cherry-Island, which lies betwixt 74 and 75 degrees Latitude; in July it froze so hard, that the Ice hung upon their . 5. As for the degrees of Cold in the Air, Dr. Fletcher tells us, that in Russia, if they go out of a warm Room into the Cold, it makes them Breath with difficulty. It is observed at Moscow, That Water thrown up into the Air falls down congealed, the Air is so Cold; and at Smolensko in Russia, the Spittle freezes before it can fall from one's Mouth to the Ground. 6. I have observed the Air grows sensibly heavier, in frosty Wether; but whether it depends on any frigorifick Atoms dispersed through the Air, or not, I shall leave to be decided by further Trials. In Northern Countries it is observed, That foggy Wether presently vanishes when Frost gins; the moist Vapours being, by that, condensed and precipitated, and the Surface of the Earth so closed up, that other Vapours were repressed, and kept from rising; and the Air hath been by several observed to have been much more clear in the Winter, here in England, and Sweedland, and elsewhere, than at other times. 7. The Refraction of Luminaries in the Northern Air in Nova Zembla is so great, that the Dutchmen observed the Sun to appear to them 14 Days sooner than it ought to have done. And Capt. James tells us, That he observed the Latitude of Charlton-Island to vary 52 Minutes, and the Sun to rise 20 Minutes sooner than it ought to rise: Besides several Instances of Refraction, laid down in the History of the Air. 8. To what we have said, of the Coldness of the Air; we shall subjoin the Relations and Observations of Navigators, which we shall either propose as promiscuous, or in Confirmation of the three following Observations. 1. That the greater or lesser Coldness of the Air in several Climates and Countries, is nothing near so regularly proportionate to their Respective distances, from the Pole or their Vicinity to the Equator as Men are wont to presume. It hath been observed, That of Places of an equal distance from the Northern and Southern Poles, those near the latter are Colder. Tho' in Moscow, the Cold is almost intolerable; yet in Edinburgh, which is a degree more Northwards, the Air is temperate enough, and the Snow seldom lies on the Ground. Mr. Pool in his Northern Voyage tells us, That it did not freeze near so hard near the 79th degree as in the 73d. And tho' Nova Zembla, lies near 4, 5 and 6 degrees more Southerly from the Pole than Greenland, yet the latter hath Grass and Trees and such Beasts as feed upon them; whereas in Nova Zembla there is no Grass and only such Beasts as feed on Flesh. To which I shall add, That Josephus Acosta tells us, That under the Line, when the Sun was in the Zenith and just entered into Aries, in March, he felt himself very Cold; and he likewise tells us, That under the Burning Zone in Quitto and the Plains of Peru the Air is temperate; at Potofi very Cold; and in Aethiopia, Brasile and the Moluccoes very Hot. And he observes further, That Snow lies on the tops of the Hills, and that it is extremely Cold, when the Sun is for their Zenith under the Line. Mr. Hudson in his Voyage hath observed, That one Day, they were much disturbed with Ice; and that the next Day, it was very Hot: And we are further informed by Acosta, That tho' the Seas of Mozambigus and Ormus in the East, and Panama in the West, are very Hot; yet that of Peru of the same height is very Cold. And Capt. James' Observes, That tho' Charlton-Island is Colder than Nova Zembla, yet is it of the same Latitude with Cambridge. To which I shall subjoin, That an English Navigator tells us, That tho' Pustozera in Russia is 68 ½ degrees, yet it is well inhabited, and a Town of great Trade. And in Hudson's Voyage it was observed, that beyond 80 degrees they found it moderately warm. 2. The next Observation is, That the degree both of Heat and Cold in the Air may be much greater in the same Climate, and the same Place, at several seasons of the year, or even at several times of the same Day, than most Men would believe. In Proof of this Proposition we shall produce the following Testimonies of Travellers and of Navigators. And 1. That there is a great variety Weather in Russia, Dr. Fletcher witnesses, who observes, that tho' all Winter the Ground is covered with Snow and the Fields frozen up; yet the Fields in the Summer are covered with flowers and filled with the delightful noise of Birds; and then the Wether is as much too Hot, as it was before Cold; June, July and August being warmer than the Summer in England: And the like is confirmed by the Observations of others, amongst whom Olearius tells us, that at Moscow he saw Melons of 40 Pound weight better than those in Italy. And at Pequin, the Royal City of China, tho' it is but 42 degrees Latitude; yet in the Winter, Martinius the Jesuit tells, us it is a hard frost for four Months together, so that all the Rivers are froze up. And Prosper Alpinus tells us, that Grand Cairo, which is only 6 degrees from the Tropic of Cancer, tho' the Summers are insupportably Hot; yet the Winters are considerably Cold: And one thing he there takes notice of is, That in that Place they are seldom or never troubled with Distillations or Rheums. And Purchase tells us, That in Greenland one Day will be extremely Cold and the next as violent Hot; so that at Midnight Tobacco may be lighted at the Sunbeams, by the help of a Glass: To which Relations I shall add, That Capt. James tells us, That in Charlton-Island, tho' the Winter was excessive Cold; yet in June it was so Hot, with Thunder and Lightning, That the Men were forced to go a shore to cool themselves in the Water. Alpinus tells us likewise, that in Egypt the Air is some part of the Day extremely Hot and at other times very temperate and cool. And Olearius tells us, That travelling over Mount Taurus in Persia; tho' it was too Hot in the Day for them to proceed in their Journey; yet at Night they were so benumbed with the Cold, That they were scarce able to light off their Horses; and the same Traveller observed at Fallu in Persia both Lightning and Thunder, Winds, Snow, Rain and Ice, in one Night. And in Charlton-Island tho' the Heat of the Sun in June be insupportable in the Day; yet at Night, the Cold is strong enough to freeze Water, in Vessels, an Inch thick. 3. The third Observation is, That in many Places the Temperature of the Air, as to Cold and Heat, seems not to depend so much on the Elevation of the Pole, as upon the Nature and Circumstances of the Winds that Blow there. It is commonly known, That in this Part of the World, Northerly and North-easterly Winds are accompanied with Cold, and in Winter with Frost: But I once observed here in England a Southwind when it froze hard; and Capt. James in his Voyage hath observed the like: And Prosper Alpinus observes in Egypt, That the Northwinds are extraordinary cooling; and that upon the Blowing of the Aetesian Winds the Plague ceases, at Grand Cairo. That this cooling Quality depends on the changes it receives from the Places it passes over, is highly probable, as well as that it acquires other Qualities the like way. Acosta Lib. 3. Cap. 9 Takes notice of Winds, That, in some Parts of the Indies, so corrode Iron-gates, That they will crumble away in one's Fingers. And the same Author tells us, That tho' in Spain an Easterly-wind is Hot and troubles one; yet in Murria, it is Cold and healthful; but in Carthagena not far from the former Place, it is troublesome and unhealthful. The Meridional (which they of the Ocean call South, and those of the Mediterranean Sea, Mezzo Giorno) is commonly Rainy and Boisterous; and in the same City, I speak of, it is wholesome and pleasant. And in Peru, he says, the South and South-west-winds are very pleasing. How the Winds come by these Qualities I shall not now dispute; but to give some light into the matter I shall propose the following Experiment. Setting a Weatherglass with a flat Basis upon a Board, and Blowing several times upon it with a large pair of Bellows, tho' the Air seemed Cold to my Hand; yet the Pendulous drop ascended a little, the Air being a little heated in the Bellows: But if the Clack of the Bellows was so fastened, That the Air must wholly enter in at the Nose of it; the stream of Air, which was by that means drawn toward the Weatherglass from the Window, being cooler, would cause the Bubble to subside. But having provided such a Tile as they lay on the ridges of Houses and filled the hollow side with a Mixture of Snow and Salt, and Part of that Mixture being placed about the Bellows; I found, That the Air blown upon my Hand was, by that means, highly refrigerated: And this Air being blown upon the Ball of a common Weatherglass, the Water manifestly ascended; but subsided again, when we left off blowing. But to prosecute the Trial, we drew back the Nose of the Bellows, and upon that, the Wind blowing along that Cavity upon the Weatherglass, manifested a higher degree of Coldness. But tho' it from hence appears, That frigorifick Atoms may refrigerate the Air; yet I believe not, that all Winds must necessarily be cooled so; since the Cold Air near the Poles swimming upon that which fills the lower Part of the Atmosphere, may, for want of a Reflection of the Sunbeams, be so Cold, as to cool the Air suddenly, when by the falling of Rain it is beat down upon us: For Acosta hath observed, upon Mountains higher than the Alps, That the Air was extremely Cold. And the Hollanders who failed within 17 degrees of the Pole observed, That their Cold Winds were chief Northerly and North-easterly. But, To conclude this Title, I shall add an instance or two to show, That Cold Winds receive not so much their Qualities from the Quarters from whence they Blow, as from the Regions over which they pass. For Mr. Wood tells us, That tho' in England the most troublesome and unwholesome Winds came from the Sea; yet in New-England those are the most wholesome: Because the North-east-wind coming from the Sea thaws the Ice and melts the Snow; but the North-west-wind coming over the Land causes Cold. And Capt. James observed the like in Charlton-Island, viz. That the Southwind was Coldest which came over a frozen Tract of Land. Particulars referrable to the XVIII Title. 1. The little sealed Weatherglass being immersed in Water, contained in a Glass-Vial greased in the inside, when the Water was froze, and the Ball of the Weatherglass was incrustated, being taken out, the Ice was broke off: Upon which the Tinged Liquor immediately risen in the shank of the Weatherglass; but presently subsided again below the former Mark; from whence it appears, That the Air may communicate a greater degree of Cold than Ice itself. 2. Having placed a Weatherglass, made by the Standard at Gresham-College, in a Cellar, where Beer continued unfroze in a very sharp Winter; last Night and this Morning the Tinged Liquor stood 2 Divisions and ⅛ above the freezing Mark; but being removed into the Garden, it subsided to the freezing Mark: But tho' the Cellar was warmer than the Air; yet it was not so warm as my Chamber; the Weatherglass there standing two Inches above the freezing Mark, in the Morning before the fire was made; and in the Summer the Tinged Spirit ascended to the 8th 9th and sometimes almost to the tenth Mark. 3. The last Night being rendered very Cold by Snow, Frost and Wind; this Morning, the Weatherglass being removed into the Garden, the Tinged Spirit subsided two Divisions below the freezing Mark: Yet the Cellar did not become so much Hotter, by an 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉; but that Oil of Aniseeds continued undissolved in it till, the next Morning, tho' the moderate warmth of Spring or Autumn is sufficient to keep it fluid. 4. A Weatherglass being held in the Stream of Water as it came reaking Hot out of the Pump, the Liquor subsided considerably; and being carried to my Chamber, the Air there being Colder than the Water, it was depressed lower. 5. Having held a Weatherglass in the reaking stream of Pump-Water, the Spirit risen about 5 Inches higher than it did at a Well in Oxford; and being in some measure immersed in a Spring that usually smokes in the Winter, it was raised a little higher. And the Weatherglass being placed on the North side of the House about Noon, I found that the temper of the Air then, was much the same with the temper of the smoking Spring. 6. Feb. 19 The Frost having continued 3 Days, the Spirit was raised as high, by the warmth of the Spring as it used to be. The next Day the Spring beginning to smoke, the warmth of the Water raised the Spirit near a quarter of an Inch higher than it used to rise at the Springhead some Months ago. And the Water was then much warmer than the Air, for the Spirit when brought to my Chamber subsided; the Ground without being covered with a little Snow 7. A Gentleman told me, That he had observed the Tinged Spirit sometimes higher, when it was frosty, than when it was not. And he further told me, That the Weatherglass being left in Water till it was froze, when it was cleared of the Ice and exposed to the Air, the Spirit manifesty subsided. The size of the Ball of this Weatherglass was as big as that of a large Crab, and the Stem was about 2 foot and ½ long. And the distance betwixt the station which the Spirit rested at in the Water and the Air was above three Inches. A Relation given me by an Ingenious Gentleman lately returned out of Poland. 1. In frosty clear Wether, he observed the Sun and two Parhelions one Eastward and the other Westward; betwixt ten and twelve a Clock; and when the Sunshine appeared it was full of glittering Particles of Ice. 2. A Dutch and a Scotch Ship having sailed beyond Greenland, within one degree of the Pole, they observed, That tho' there were vast Regions of Ice near the shores; yet near the Pole, the Sea was open and free enough. From the North-East they observed, That there came a great rolling Sea, not unlike the Spanish Seas: And that the Cold was no violenter than that in Greenland. And further they observed, That sailing from Greenland, the Compass first varied a Point and then two, and when they came near the Pole, the Compass varied 4 Points, and that towards the East. The Captain likewise told me, That they are troubled at Sea, sometimes with thick Fogs, some of which last half a Day, others a Day; and others a whole Day. And he likewise told me, That lying at Anchor near Bellsound on the coast of Greenland, near a very high Rock, he and some others got to the top of it; which they judged to be half a Mile high: And when they came there; they found the Wether clear and the Sky serene, and so Hot that they were forced to strip themselves: But below they could discern a thick fog; which when they came down, they found was very Cold, and Dark. A Passage taken out of the Czars-Doctor's Letter. 1. At Vologda in the North-East from Moscow we found the Cold Wether in December not to last 3 Days; but the Rain was unusual and dangerous. And for 30 years past the Winters have been so moderate, That People are not froze on the Roads in several Postures; but sometimes they lose their Noses, and have their Faces froze. 2. The Warmer the Room is in the Day, the thicker the Hoar is at Night upon the Glass; being sometimes an Inch thick: And if it be a small Frost, The Nails of the Windows and Doors will be tipped with Frost. The Falconers say. That the Birds creep under the Snow at Nights. Bears make themselves Caves against Winter, and I remember I kept one two Days without meat or drink; he in the mean time, making a Lather with his Tongue and sucking his Paws. 3. A Wind from the Sea causes a Thaw as well as at Archangel. The Air is so healthful they use very little Physic, so that the Poorer sort live 80 or 100 years old. TITLE XIX. Of the strange Effects of Cold Of the strange Effects of Cold. THE Dutch tell us, That they found it so Cold in Nova Zembla that when their Sheets were washed and hung to dry by a fire, one side would freeze as the other thawed, and that they themselves were so Cold, That they could not warm themselves by the fire; for they usually smelled their stockings burn, before they were sensible of the Heat. And Capt. James tells us, That in Charlton-Island, the one side of Water in a Vessel froze, whilst the other was next the fire. To these Relations I shall add, That Marcus Polus was told, That on a Plain, which was betwixt two of the highest Hills in the World; fire would neither burn so briskly, nor boil things so effectually as in other Places; which I am the more unwilling to reject as impossible: Because if Snow and Ice own their Coldness to something which reigns in the Air, Nature may make the Air as Cold in any other Northern Climates; Saline Expirations being every where dispersed through the Earth and Sea. And this Cold is so violent, that Water being poured on a stool and a Tankard placed upon it; by a Mixture of Snow and Salt, the Tankard will be so frozen to the stool, That the one being lift up, raises the other along with it. 2. Gerat de Veer, says, That if they put a Nail into their Mouth it would be froze, and bring Blood along with it when taken away. And Dr. Fletcher tells us, That in Muscovy, if one hold a Pot in ones Hand; being froze to it, it will pull off the skin at Parting. And in Nova Zembla, it hath been observed to be so Cold, That it froze Salt Water two Inches thick. 3. In the Marketplace at Moscow, Olearius tells us, That the extreme Cold caused a Clift a foot broad and several Inches long; and that considerable Cliffs will be made by the Cold, I am informed by others: And the Dutch in Nova Zembla acquaint us, That the Ground was so froze, that they were not able to thaw it by burning Wood upon it. 4. As for the Effects of Cold on compound Bodies, etc. That it will freeze Beer, Ale, Vinegar, Oil, common Wine, and even Sack and Alicant we have already shown; and that it hath considerable Effects on Wood, Bricks, Stone, Vessels of Glass, Earth, and even Pewter and Iron themselves. To which I shall add, That tho' Cold preserves some Plants; yet an excessive degree of it destroys them. 5. Capt. James tells us, That he found the Cold when at the highest degree insupportable; and Olearius acquaints us, that sometimes the Cold in Muscovy is so excessive, That neither motion nor resist the ill Effects of it; but in Moscow the Air is very good and healthly, the Plague very seldom happening there. And Dr. Fletcher tells us, That in Russia it is so Cold sometimes, That People fall Dead in the Streets, and that the Bears and Wolves invade and Plunder the Towns in whole Troops. And the Effects of Cold have been found so strange sometimes, That it hath caused Blisters to rise, not only upon the Hands and Face but their Arms and Legs: Besides these Instances, Capt. James tells us, That their would be covered over with Frost, and Iceicles would so hang to their Hair, That he was forced to shave his Head and Face, that they might have nothing to hang at. And Purchas says, That their very shoes would be covered over with a Hoar-Frost on the inside, so that they were not able to wear them. And I am told, That an Army of 40000 of the Turks all perished at once by excessive Cold. I am also informed, That a Province of Poland, of the same height of the Pole with Normandy, is subject to some sort of Colds, which occasion a peculiar kind of Sickness and at other time's Death. And Cancerous Sores are as fatal as those caused by Hot corroding Humours; and those that die of the Cold, either are seized with a drowziness and Coldness of the Extreme Parts, and die in a sleep, or having their Guts and Reins first froze and then Gangreed and Mortified, vomit every thing they take, and then languish with violent pain and Dye; and their Bodies being opened, their Guts are black, and as if it were glued together. 6. What effects Cold hath upon other Animals, hath not been much observed by Authors: But a French Author tells us, That the Cold in ukrain as the Polanders call it, is sometimes so great, That it destroys Horses and some other tame Beasts. And the same Author mentions a fourfooted Creature, called Bohack, peculiar to that Province, one of which being dug out of the Ground where he was froze, (for they usually hid themselves there in the Winter) when they were about to flay him, the sense of Pain recovered him; and this was presented to a Polish Lord from whom I had the Relation. 7. It is reported, That in the Northern Countries, the Birds and wild Beasts are usually turned white: But tho' I done't wholly reject it as false; yet I cannot believe it universally true. But this is certain, That good Author's mention, white Bears and Foxes in Nova Zembla, and white Partridges upon the Snowy Alps; and I have heard of white Pheasants in Savoy. What may be the Reason of this Colour I shall not dispute, nor shall I determine, whether it be caused by any seminal Impressions, or the Imagination of the Females, who have Snow always as an Object before them: But that all Beasts and Fowls in the Northern Climates are of that white colour I find is a Mistake; for I have seen Deers skins brought from Greenland of a Dun colour. Yet one thing which is very strange is, That in Greenland and Livonia Hares become white in the Winter, and return to their Natural colour again in the Summer. And Capt. James tells us, of Foxes in Greenland which are pied black and white. Particulars referrable to the XIX Title. 1. Lieutenant G. Drummon told me, That at Smolensco, the Barrels of Beer, being frozen a considerable thickness; the Liquor contained within was much stronger. 2. Two Swedish Ambassadors confirmed to me, That the Hares in Muscovy, change from their Natural colour to white in the Winter, and recover their own colour in the Summer; and that on one side the River Duna which separates Livonia and Muscovy, the Hares are white, and on the other side of ordinary colours. 3. It is observed in Russia, That if a Man, touches his Tongue with the Metalline Head of a Cane, it freezes his tongue immediately; so that he cannot separate it without much Pain: For the Parts of the Metal being at rest, and the Spittle whose Parts are in a weak Motion, striking against the Metalline Body, are wholly deprived of it, and consequently freeze. So in a Billiard-Table one Bowl in Motion striking against another not in Motion, communicates as much of its Motion as it can to the other, and loses it's own; and so the Vapours and steams in a Room, in frosty Wether striking against the Glass-Windows, are deprived of their Motion and froze, which is observed to be much thicker upon the Glass in Russia than here in England. A Note out of Martinius in his account of China. This Author tells us, That at Peking, tho' the Pole be not elevated above 42 degrees; yet for four Months together, from the middle of November, the Rivers are froze in one Day, so that they bear Coaches and Horses. A Note taken out of Martinius Cromerus his Polonia. The Cold is so violent in these Countries sometimes, That the Trees whither at the Roots, and Water is froze as it falls through the Air; and the Waters are froze up for two Months, so that they bear Horses loaden, and Coaches. And this Author tells us, That he passed over the Weisell in Massovia with a Coach and Horses, and other Horsemen. And in Prussia the Fishing in the Ice began after the beginning of November, and lasted till March was ended. Another Note out of the same. 1. They catch Fish more commodiously in Winter than Summer; for breaking holes in several Places in the Ice, a Net being cast into one of them, and ropes fastened to it, Men with Poles, and Horses, draw the Net from one Place to another. 2. I am told that at Warsaw, in twelve Hours the Water was froze 4 Inches downwards. One that sailed to make Discoveries beyond the Arctic Circle, told me, He could eat as much in one Day, as in ten here; and that after they had sailed over a deep blue Sea, they came to one as black as Ink, which being sounded, it was above 70 Fathom. Sack being froze, and thawed again, presently lost its Vigour. 3. In these Parts the Frost penetrates the Ground five Foot; and the Ice in Iberia in the River Ob, is said to be a Fathom and a half thick; there being there but twelve Weeks in the whole Year without Frost: The Rivers have breathing places a Mile long, out of which Fumes ascend, as out of a Cellar, when the Door is opened. Death by Cold is not painful, if it be intense. Cold dries excessively, cleaves the Earth, and causes Timber to crack. TITLE XX. Experiments concerning the Weight of Bodies frozen and unfrozen. The Weight of Bodies frozen and unfrozen. 1. TO try whether Bodies upon freezing would grow heavier, since Epicurus and other Atomists, suppose Congelation to depend upon the crowding in of frigorifick Atoms; we exposed Eggs to be froze all Night, and in the Morning we found they had lost four Grains of their Weight, which we suspected to proceed from the Avolition of some Exhalations through the Shell; since at other times we observed, That Eggs counterpoised lost eight Grains of their Weight, in some process of Time. 2. Water froze and weighed, counterpoised a Grain and a little more, than when it was thawed: But the Experiment being made in a Glass with a long Stem, hermetically sealed when the Water was froze; it was as heavy or heavier after it was thawed; and the same Equality of Weight betwixt frozen and unfrozen Water, happened in other Experiments. 3. Stones being weighed after exposed to the cold Air, and also in a warm Air, they seemed to discover an Increase of Weight; but I suspected it proceeded from Water imbibed into their Pores, since Stones are observed to increase their Weight in Water: And further, because one that was well polished, and not apt to imbibe Water, retained barely its own Weight. So that the Doctrine of the Epicurean Freezing, must be invalid, except he supposes the frigorifick Atoms, like those of a Loadstone, to be without Weight. An Appendix to the XX Title. The foregoing Experiments, may not only satisfy us, That the Doctrine of the Epicureans is erroneous, but may likewise help us to correct some extravagant Relations, on the other Hand: For Helmont tells us, That Water thawed in a Vessel Hermetically sealed, was ⅛ heavier than before. But perhaps this Difference might in part depend on the Access of Vapours on the outside the Glass. In opposition to what Manalphus tells us, I found, That Water froze in a Metalline Porringer, in one Experiment lost 50, in another 60 Grains of its Weight; which I attributed to an Avolition of some Parts of the Water, since when we ordered the Matter so, that no Water could steam out, there was no considerable Increase or Decrease in the Weight of Water froze or thawed. Particulars referrable to the XX Title. 1. Quicksilver being weighed in the Air, and afterwards counterpoised in Water, when by the application of a Mixture of Snow and Salt, it began to freeze; the Bubble weighed ¾ of a Grain less than before. A Globe of Snow rammed into a Mould, whose Diameter was an Inch, weighed 112 Grains. A Globe of Ice of the same Diameter weighed, 2 Drams, and 5 Grains. 2. After a long Frost and Snow, the Liquor in the gauged Weatherglass stood below the first Mark; but the Mercury in the Baroscope stood at near 2/● below 29 Inches; which perhaps might be attributed to the high Wind. 3. Four Ounces of Snow being counter poised were exposed to the Frost all Night, and at 10 or 11 in the Morning, had lost near 30 Grains, which Parts seemed to have been evaporated; the melted Liquor in the Bottom of the Scale amounting to no more than 8 Grains. 4. Two Ounces of Snow depressed flat, so as to form a large Superficies, and counterpoised, in a Night's time, lost 55 Grains; no Water being found in the Scale; and two Hours after, the Decrement was 63 Grains, none of the Snow appearing yet to be melted. TITLE XXI. Promiscuous Experiments and Observations concerning Cold. Whether Frost hinder odoriferous Effluvia from exerting their Power. 1. SEveral Flowers being gathered in December and January, and hastily smel●ed 〈◊〉 had no sensible effect on the Sensory, whic● Phaenomenon I attributed to the Frost, hindering a sufficient Quantity of spirituous Sap from rising up into them; and not that it prevented those spirituous Parts from emitting Effluvia; since a vigorous fresh Primrose, had an Odour genuine and sweet. 2. Rose-water being froze, when it was wholly Ice, afforded a genuine Scent, but something fainter, than when it was thawed again; but in making these Experiments it is requisite, that the Body smelled at, should not be held too long near the Nose, lest the warmth of one's Face should help to excite those Odoriferous Parts, and consequently frustrate the Trial. 3. Stinking Water being exposed to the Cold and froze, was altogether inodorous. 4. It is reported by several, and attested by Olearius, That the Russians and Livonians, enable themselves to bear Cold extremely, by going out of their Store naked, immediately into cold Water, and even Ice itself. 5. Having made use of a good burning-Glass to concentre the Rays of the Moon, I could neither perceive them cold or hot; tho' Sanctorius tells us, That they are hot, and that being concentred, and cast upon the Ball of a common Weatherglass, the Water was sensibly depressed; but since my Glass, for as much as I can gather from the Narrative, was better than his, I must suspend my Assent, till further satisfied by Experience; for since he tells us, that several of his Scholars stood by to watch the Event, the Effect might in a great measure depend on the Warmth of their Breath. One Particular referrable to the XXI Title. The Samojedes themselves with Renes Skins, the Hair being outward; and I have found a Pair of Cangies warmer than furred Gloves. They are chief made use of for the Sledge, tho' one may walk in the Snow with them, it being so dry, that a Scarlet being covered all over with it, it will brush off without wetting or endamaging it. To the XI Title. The force of Expansion by Cold. 1. The Barrel of a Gun which was about a Foot long, and of a proportionable Diameter, had the Touchhole riveted up, and a Screw fitted to the Nose of the Barrel, which being done, it was filled full of Water, and suspended in a Perpendicular Line: The Screw having been thrust down as forcibly as a Man could; in a frosty Night, the congealed Ice raised the Screw considerably, so that Ice had made its way out at the sides of the Barrel: But the Experiment being repeated, and the Intervals of the Screw filled up with melted Bees-wax, the expanded Ice not being able to raise it, the Nose of the Barrel was cracked obliquely; besides several other Flaws in other Places, which gave way to the Wind blown into the Barrel to try it. An Appendix to the XVII Title. Of the Effects of Nitre in freezing. Bartholinus citeing an Experiment, wherein the Proportion betwixt Nitre and Water was 35 to 100; to try the success of it, we mixed a Pound of Salt-Petre with 3 Pounds of Water, and stirring it about constantly, as Cabaeus directs, in an Hour and half we perceived not the least Ice; whereas, according to him, it ought to have been wholly froze in less time; but we could not perceive the Vapours on the outside of the Glass in the least froze. For a further Trial, we mixed two Ounces of Salt-Petre with six of Water in a Glass-Vial, but by all the shaking we could not produce the least Ice; tho' whilst the Nitre was dissolving the Mixture was sensibly colder; and the same we have observed to happen upon a Dissolution of Common Salt; tho' the Degree of Cold was not sufficient for Congelation, which I was satisfied in, by removing a Thermoscope out of the Mixture of Nitre and Water, into Water which was placed in Snow and Salt: For by that means the Liquor in the Weatherglass subsided in the latter about 3 Inches; so that I am apt to think the Learned Cabaeus mistook Crystals of Nitre for Ice. It is believed by most Watermens, That the Water gins to freeze at the bottom, because they observe large Pieces of Ice rise from the bottom of the Water: But the Truth of it is very reasonably questioned, since we not only see, that Water in Vessels, but in Wells, gins to freeze at the Top; and several Arguments in proof of the contrary may be found in our Section of the Primum frigidum. And as for those Pieces of Ice, which they observe to emerge, that Phaenomenon may easily be solved, without supposing the Water to begin to freeze at the Bottom: For since the Water, which runs along the sides of the Banks being froze, several Stones may stick to it; they by their Weight may cause it to subside, when it is partly loosened by the Heat of the Sun, and the Water, by that Rarifaction becomes lighter: Yet, when the Water above is cooled, and the Water below being warmer, hath melted the Ice in some measure, and loosened some of those Stones which were before froze to it; the Ice becoming specifically lighter than the Water, must consequently emerge. On which occasion, I shall here observe, that Capt. James Hall takes notice, That they found a Stone of three hundred weight upon a Piece of Ice. In confirmation of our Solution of this Phaenomenon, I might allege the Experiments laid down in the Section of the Duration of Ice. And it were to be wished, that for a further Decision of this matter, that either Divers were sent down, or Instruments which would bring up Ice if any were there. We took a sealed Weatherglass, and having inverted the Stem of it when furnished with Spirit of Wine, so that, that being placed in a Hole purposely made in a Box, the Ball of the Weatherglass rested on the Box; about that we placed a Mixture of Snow and Salt, and found, that presently the Spirit of Wine was retracted. So that Liquors may be condensed, without the assistance of their Gravity, to depress and cause the Parts of the Body to sink together: But whether in this case, the Contraction was assisted by the Tenacity of the Liquor or the Springiness of some Elastic Particles, will be inquired into in a more proper Place. Frogs and Toads being taken up from under Ice, were brisk and lively; and it is observed, that in frosty Wether they generally lie in the Bottom of Pits, for their Security. Paralipomena to the TWO and XX Titles, of the frost getting into hard and solid Bodies. Of the Effects of Frost on solid Bodies. In England it hath been observed, That Wood whose Diameter, was a Foot through hath been froze; and in Poland the Frost hath been so powerful, that it hath rendered the Timber so hard, that Hatchets would not cut it; and the Wood with which the Houses were covered would give Cracks as loud as Pistols. And I am told by one, that his Bow being froze, if he did not take a great deal of Care in thawing it, it would break. Marle and Chalk will be shattered with the Frost, the Texture of those Bodies being by that means opened and rendered more fit to nourish Plants and Grass. And I am told by an Experienced Mason, that even free stone, of which Houses are built, will crack and flaw in frosty Wether. And it is observed in England, That stones dug up in the beginning of Summer and seasoned in the Air are not near so subject to flaw as those that are dug up and worked, whilst the Frost continues. And it is further observed, That both Earthen as well as Glass-Vessels are considerably impaired by the Effects of Frost upon them. To which instances I shall add the Testimony of Maistre Bernard Palissy who says, That tho' the stones of the Mountain Ardenne are harder than Marble; yet for fear of Frost they are drawn out of the Quarries in the Winter: And he further adds, That in the Winter the Rocks sometimes crack and fall down without being cut. And it hath been observed, That Iron-Instruments brought out of the Cold into a warm Room have been covered over with a white Hoar; and it is not only confirmed by foreign Artists but several here, That Cold hath so great an Effect on Steel as to make several Pieces of Metal more brittle than in the Summer; so that they are then forced to work them another way and to give them a different temper. Hot Water does not frieze sooner than Cold. It being a Tradition, and also taught by Aristotle, That Hot Water is sooner froze than Cold; to determine the matter, I made the following Experiments. Cold Water being exposed to freeze in one Porringer, boiled Water cooled in another, and Hot Water in a Third, at 8 a Clock; the Cold Water began to freeze at ¼ after ten; the Boiled Water cooled, at ¾ past ten; and the Hot Water at ¼ an hour past Eleven. And the like success happened, when the Experiment was tried a second time in Metalline Vessels: And the Experiment being again tried with greater exactness, the Cold Water and the rest being exposed to freeze at ¼ after 6, the first beganto frieze ¼ after 7; the Water heated and cooled again ¾ after 7, and the Hot Water was not froze ½ an hour after Eight. The like Experiment being tried with Water contained in Glass-Cylinders of an equal Boar sealed at one end, we found that there was very little difference in the time of their Congelation, when immersed in a Mixture of Snow Salt and Water; but once, when the end of one of the Cylinders was drawn smaller than Ordinary, the smallness of the Pipe occasioned the Hot Water to begin to freeze sooner than the Cold Water. Postcript. Accidentally looking upon the Circulus Pisanus of Berigardus, I found, That tho' that Author opposes Aristotle in other Points; yet he agrees with Him, That Hot Water cooled, will sooner freeze than ordinary Cold Water; but having tried the Experiment, I observed, That both being exposed to freeze when by a Weatherglass I found them of the same temper, my Domestic who attended them, took notice also that they both began to freeze at one time. And tho' Berigardus further wonders, That warm Salt-Water should be less subject to freeze for being Salt; yet from▪ Experiments already laid down, it abundantly appears, That tho' Salt Externally applied promotes it, yet Internally being dissolved in Water, it prevents Congelation. Particulars referrable to several Titles. For a further Confirmation of the VI Title. I shall add that Purchas relates Lib. 4. Cap. 19 That the Samojeds, when they Bury their Dead, only cover them with a Pile of stones, and tho' the Dead Bodies may be seen through them; yet the Coldness of the Air preserves them from stinking. And the same Author tells us, That in a certain Island they preserve their Fish and Flesh, by hardening it in the Air, better than if it were corned with Salt. In Confirmation of what hath been delivered under the VII Title, I exposed several Vials filled with Water and unstopped, to be froze, and found that the Bottles were broke in pieces, by the Expansion of the frozen Water; so that the Phaenomenon could not be attributed to Nature's abhorrency of a Vacuum: For if either the Expanded Water could have made its way by stretching the Glass, or leaving the Superficial Ice congealed at first in the Neck, or any other way easier than to break the Vessel; the Vessel would probably be left entire, I say probably, because sometimes in such Experiments something may intervene which requires further Trials and Observations to discover: Since I have in other Experiments made it appear, That the Water beginning to freeze at the Bottom risen a considerable height in the Stem without breaking the Bottle, and I have sometimes had a good deal of a Liquor froze in a stopped Vial without breaking it, as if the success were varied by some uncommon Properties in the Glass, or some peculiar softness of the Ice. In Confirmation of what is delivered in the VII Title, of the Expansion of freezing Water, I shall add, That the Capacity of a large Bottle being filled with Water, except the Neck, and that filled with Oil, the expanding Water not only elevated the Cork; but raised it several Inches; it being supported by a Cylinder, partly consisting of Oily, and partly of Watery Particles of Ice. It is a General Tradition amongst Fishermen, That when Ponds or Rivers are froze up, except several holes are broke up for the Air to communicate with the Water, the Fishes will be suffocated; and Olaus Magnus, tells us, That Fishes are usually found suffocated, when a thaw comes, where Veins of living Water do not enter. But I am not satisfied, whether, if the Tradition be true, they may not be killed either by some Subterraneal Steams or their own Excrementitious Effluvia prevented, by the Ice, from making their way out of the Water; and it may be questioned further, whether this Phaenomenon may not be caused, by excessive Cold as well as for want of Air. Wherefore to satisfy myself, whether the Vulgar Opinion be true or not, I enclosed some Gudgeons in a large Glass with a long Neck, and having froze the Water in the Neck by applying a Mixture of Snow and Salt, I found, That the Fishes lived a considerable time. And the like I observed, when the same Fishes were contained in an Earthen Vessel with a little Water frozen over: Where the External Air was wholly separated, and prevented from communicating with the Water under the Ice; yet one thing observable was, That there was a large Bubble of Air, under the Ice, which I suppose came from the Fish: For I have observed, not only these sort of Fish but Lamprels take in Air, and then being immersed under Water emit Bubbles, both at their Mouths and Gills. Gudgeons frozen up in Ice in a Basin recovered when it was thawed; but some that continued 3 Days in Ice revived not. Frogs froze in Water till they were all enclosed with Ice, and till one of them was stiff with it, recovered when it was thawed, and Swum about; tho' before some of them lay with their Bells upwards and void of Motion. As for the weight of Bodies frozen, Capt. James tells us, That Wood, that had lain all Winter under Ice would sink when cast into the Water. And he likewise tells us, That the Ice of Wine is so durable, that a Butt of Wine which was froze in the Winter; continued unthawed in May. Purchas tells us, of two pieces of Ice which they found lay fast on the Ground, the one of which was 20 fathom under Water and 12 above, and the other 18 fathom below the Surface of the Water and 10 above it. It is observed by Purchas and several others, That the Snow lying upon the Ground in Russia as well as in England makes it fruitful. Of the separation of Liquors by Cold. It would be worth while to try, what Effects Cold hath upon occult Qualities as well as manifest ones; and likewise upon Fermentation; since it is observed to retardate the working of Ale extremely; and it is observed, That Must may be preserved sweet a long time in a deep Well, or if let down into the Bottom of a River; and will when taken up, be less apt to ferment than other parcels of Must kept in the warmer Air. It hath been observed in the Northern Countries, That the most Spirituous Parts of Liquors, have been separated and Collected together by a Congelation of the Phlegm; wherefore to try what Cold would Effect in our Climates, I hung out a Bottle of Beer in a sharp Night; and found, That most Part of it being froze, the Liquor which was not froze, was very strong and Spirituous; the frozen Part being Spiritless. But Rectified Spirit of Wine tinged with Cochineel being mixed with Water, Congelation separated not their Parts, nor did it separate the red and the Watery Parts of Claret. I made several Trials upon Milk and Blood, as also on Vinegar, in which my Attempts proved insatisfactory: But a Solution of Salt being made in 24 Parts of Water, so that it was as strong as the Sea-Water about us, I caused it to be exposed to freeze in a flat Vessel, which was the larger, That the Superficies of the Water might be considerable; and when it was covered with a Cake of Ice, that being taken off, it acquired another; which, when dissolved, yielded Water, not near so Salt as that which remained unfroze; and being Hydrostatically weighed was considerably lighter. Having exposed several Vegetable and Animal Substances to be froze, I found, That by that means I could discover, their succulent juices, and squeeze them out in the form of Ice, which being done; by cutting them transversely and length ways, I could discover also the Figure and Size, of the Pores in which those Juices lodged. Amongst the Animal substances exposed to freeze, were the Eyes, and the Brains of Animals; which by being froze would be fit to be dissected; the latter, when cut in two seeming like an Apple froze, the Ventricles and i●… whole substance being filled with Icy Particles. Neither an Eye nor a Liver, lean flesh or fish▪ nor a living Frog; would be crusted over with Ice, as Eggs and Apples are, when put into Water; after they had been froze. As for the Reason why flesh is usually much impaired by being froze, I suppose it to proceed hence, viz. That the Alimental Juice being expended by freezing hath not its own texture altered only, but even the solid Vessels which contain it, are thereby bruised and crushed; for from several Experiments it is evident, That Eggs will be burst by the freezing of the Alimental Juice, and that the Textures of Stones and Vegetables will be destroyed by the Powerful Congelation of their respective Juices, which will be less wondered at, if we consider that Aqueous Parts by their Expansion were able to burst the Barrel of a Gun: Had I had leisure and conveniency I would have tried what Effects Cold hath upon Animals froze to Death; but having exposed a Rabbit to the Cold all Night, I found that only one Leg was swelled and a little stiff. But a strangled Rabbit being exposed to be froze, Ice was produced in several Parts. It is affirmed by several Modern Writers, That if Water be impregnated with the Salts of Vegetables; upon Congelation, they will represent the shape of the Plant they belong to: But notwithstanding I have several times tried the Experiment, I found it either false or very contingent; since it did not once answer Expectation. But having exposed a Lixivium of Pot-ashes to freeze; I found, That the Crystals upon the Surface of the Water were Prismatical, and that under those lay a great many thin Parallel Plates of Ice; but not ranged in such an order as to represent the shape of Trees: And tho' Bartholinus tells us, That if a Decoction of Cabbage be froze it will represent a Cabbage; yet I could never find, That the Experiment succeeded, except that once there appeared the faint resemblance of a single Leaf. But I have found, That fair Water froze would represent the shapes of Vegetables oftener than their Decoctions. And tho' Berigardus also affirms the same; yet I suspect, That he only wirt, without trying the Experiments himself. And yet, I deny not, but that prepossessed Spectators may fancy they see such things when they do not, for tho' Sea-Salt and Alum consist of Parts of determinate Figures; yet when dissolved in Water they exhibit Figures too various and extravagant, not to be referred to Chance. And on this occasion, to what hath been said I shall add, That by Distilling and rectifying Oil of Turpentine from Sea-Salt in a Glass-head, as the degrees of Heat were varied, so would the Figures of Trees be represented different on the inside the Glass. And I have several times produced the shapes of Trees from Bodies belonging to the Animal Kingdom. And I have found, That tho' Figures curious enough would be represented by Spirits, Solutions, Decoctions, Vinegar, Milk and even common Water; yet it was in vain to hope for the same success, and that the like Figures should always be afforded by the same Liquor; since very small Circumstances would vary them considerably: And in trying of such Experiments as these it may not be amiss to advertise, That it will be convenient, that the Liquor should be as shallow as it possibly may, That it may be more speedily froze. A frozen Egg being Put into Oil of Turpentine instead of common Water it gathered not about it any crusty Film. It is observed by Mr. Wood, That tho' New-England be 10 or 11 degrees remoter from the Pole; yet the Winters are much more piercing and Cold than ours. And to what hath been delivered in the XVIII Title of the infrigidating Power of Wind, I shall add, That sometimes it hath been so much more Cold than at others, That being blown through the frigorifick Mixture, it would cause not only the Spirit of Wine to subside; but being blown upon the Ball of another Weatherglass; not only the Liquor; but even Mercury itself would be forced to ascend, tho' the Vicinity of the frigorifick Mixture could not cause that Effect. And I have often tried, That when the Temperature of the Air was such, that tho' when first blown upon the Ball of a nice Thermoscope; it would not cause the Liquor to ascend; yet at another season the Tinged Liquor ascended, as if the Air by being more than ordinarily compressed in the Room, had some sensible Effect in compressing and contracting the Air included in the Thermoscope. To try whether Liquors, by losing their fluidity and becoming consistent would acquire a greater degree of Coldness, I caused the Ball of a Weatherglass to be immersed in Salad-oil, and a Solution of Minium in Vinegar, or of Quicklime in Water, either of which will coagulate the Oil; but I did not find, That the Mixture tho' consistent was Colder than the fluid Ingredients. To try whether Water was capable of Compression, we took a Glass-Ball with a long Stem, and filled it with Water within two Inches of the Top; then we Hermetically sealed it up, and freezing it from the Bottom upwards in a frigorifick Mixtre, when the included Air was compressed as much as we thought the Glass would bear, we nipped off the Apex; and found, That thereupon the Air flew out and the Water risen ¼ of an Inch above its former Surface: So that it seemed to be compressed ⅜ of the length of the Aqueous Cylinder; but whether this Phaenomenon might be occasioned, by the Spring of some latent Air in the Pores of the Water, or whether it might be occasioned by some Springiness in the Ice, or Whether the Glass being before distended and now reduced to its former Dimensions occasioned this Phaenomenon, I will not undertake to determine without further Trials. And, To what hath been observed in this Experiment, I shall add, That if the Apex were broke off before the Air was much compressed, it would cause no considerable Noise: And further, when the Experiment was a second time repeated with one of the same Glasses, and the same Liquor; it would rise ⅛ and ¼ in the Stem, higher than before, upon breaking of the Apex. CHAP. VI An Examen of Antiperistasis, as it is usually taught and proved. Arguments alleged in Favour of an Antiperistasis. THO' the Doctrine of Antiperistasis be asserted by Aristotle; and some of his followers urge Reason and Experience in favour of it, yet from what follows it will appear, That what is offered is not sufficient to maintain his Doctrine. For first it is Reasoned in favour of it, That nothing can be more requisite for the Preservation of things, and more agreeable to the wisdom and goodness of Nature, than to furnish Cold and Heat with a self invigorating Power, which each of them may exert when encompassed with the other; and that nothing is more Natural, than for one Quality, when surrounded with a Predominant one, to retire into the innermost recesses of that Body; where the force of it being increased, an occasional Exertion of that Power is called Antiperistasis. But from Reason to proceed to Experience, it is offered by the maintainers of an Antiperistasis, That in the Summer, when the lowest and uppermost Regions of the Air are insupportably Hot, the Cold flies to the middle Region of it, and there defends itself against the other two about it: And as the Cold remains in the middle Region, by virtue of an Antiperistasis, so Lightning is but an Explosion of Exhalations pinned up in the Cold. And to this it is further offered, That the Effects of Antiperistasis are not only evident in the Air, but the Earth itself; for in the Summer, when the Air above the Earth is Hot, that in Cellars to which the Cold retreats is of a contrary Quality; and on the contrary in the Winter, when the Air without is excessive Cold, that in Vaults and Cellars is warm; and even the Water drawn from Wells is warm, when at the same time Rivers themselves are covered over with Ice. And, To these things it is further offered in Favour of an Antiperistasis, That in deep Pits as well as Mines, it is observed, that the Air is troublesome hot in the Winter: And that it is further observed, That the Water in Charlton-Island hath been observed to be much Colder in June when Ice swum in it, than in December; and that a Well which furnished them with Water in December, afforded none in July; and further, That in Musco the Cellars are able to defend them in Winter from the Excessive Cold; and that even in those Gelid Climates, Water drawn out of Wells usually steams or smokes if agitated when newly drawn. Thus much being offered in favour of the Doctrine of Antiperistasis, Those Arguments exmined. it is answered on the contrary; first, as to the rational defences of it, That there it no necessity that these two Qualities should thus invigorate themselves, there being no danger of them being lost out of the World; since without the help of an Antiperistasis, there are several substances, which are plentifully stocked with matter to supply each Quality: Besides, according to the course of Nature, contrary Qualities rather destroy than preserve one another; and even the Peripatetics themselves allow, That all Agents act as much as they can. And we have several Instances in the Northern Countries, That the Natural Heat of Animals is destroyed and not increased by the help of Cold; and tho' it be commonly alleged, to show that Contraries endeavour to shun each other, That a drop of Water falling upon a Table keeps in a Globular form; yet the Reason of that seems only to be this, viz. That the specific Gravity of the drop is not so far prevalent above its Tenacity, as to cause it to spread; besides, it is prevented partly by the Ambient Pressure of the Atmosphere: And that it's Globous Figure is not owing to its aversion to spread upon a dry Body, and its disposition to shun Contraries is evident, since it retains the like Figure when mixed with fluid Oil; and Mercury on the contrary, tho' it be apt to retain a Globular Figure upon a Table, yet if put upon Gold it loses that Figure. Whether the Phaenomena of slacked Quicklime be an Argument of Antiperistasis. But to pass by what Reasons may be offered against the Doctrine of Antiperistasis: To proceed to examine what Experiments and Observations have been alleged in favour of it; I shall first observe, That tho' the slacking of Quicklime with Cold Water be generally looked upon to be an Effect of Antiperistasis; yet it appears otherwise, since it will cause a much more violent Ebullition, if boiling Water be made use of instead of Cold; the Parts of the hot Liquor being much more apt to penetrate and dissolve it, and to set the Igneous Parts at Liberty; for which Reason, Spirit of Salt causes still a stronger ferment than hot Water. But to show further, That Water slacks not Lime, because its Coldness keeps in, and thereby invigorates the Power of the Igneous fiery Parts of the Lime, I put a piece into Oil of Turpentine, which did not in the least dissolve it, nor did Spirit of Wine, tho' upon the removal of it into Water, it was presently dissolved. Another Argument Examined. Another Argument alleged for an Antiperistasis, is the freezing of a Pot to the Top of a stool at the fire side, by a mixture of Snow and Salt; but this Experiment having likewise succeeded, where there was no fire near, it could not be said that the Effect depended upon the force of the fire invigorating the Cold. Another Experiment employed by the Asserters of an Antiperistasis is, That if a Pot of Snow be set over the fire, and a Vial full of Water be placed in the middle of it, it will upon the melting of the Snow be turned into Ice; but this Experiment having been often tried, succeeded not; yet tho' it should, any other Agent which would melt the Ice would as soon produce the Effect. What the severel Regions of the Air offer in Favour of Antiperistasis. But as a further Argument of an Antiperistasis, it is urged, that in the Summer the lower and third Regions of the Air are Hot, and the middlemost Cold, which to me seems rather asserted; than proved, for not to insist on this, viz. That according to the Peripatetics, the Natural State of the Air being Hot, I see not how it should be Cold in Summer, nor can I see why the Third Region should be so Hot, since it lies so far from the Superficies of the Earth, that the reflected Rays of the Sun cannot reach it; and tho' it be urged that it is Hot, because Meteors have been kindled there; yet the same Argument would prove the middle Region Hot, since Meteors and Lightning have been observed there; and even in the lower Region; it being common in Storms for't hose fires called Helena, or Castor and Pollux, to hover about the Masts of Ships. An Aphorism of Hypocrates examined. It is an Aphorism of the Great Hypocrates, ventres byme esse Calidiores; but this being grounded upon a Supposition that Digestion depends on Heat, and therefore it must be greater in Winter, because Men have sharper Appetites; All that I need to offer to repugn this, is, that Digestion is not performed by Heat; since several voracious Fishes digest very strongly, whose Stomaches and Blood is Cold. But tho' Concoction depended chief upon Heat; yet the greater Heat of the Stomach in Winter could not be attributed to Antiperistasis; but a Retention of Hot Humours generated in the Heart, which gradually increasing, produce in all Parts of the Body a more than ordinary Heat, and by that means prepare a greater Quantity of the Stomachical Menstruum. Bends Contraries themselves, in respect of other Qualities, agree in this, That they increase Appetite, as Spices, Wine, and Vinegar; and also Wormwood and Juice of Lemons. And Fromundus hath observed, That he himself hath been taken with a 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 upon walking upon Snow, which since they are not so frequent in the Northern and Colder Climates, I am apt to believe proceed from some other Particles conveyed into the Blood along with those frigorifick Atoms. Hail is thought by the Aristotelians to be generated in the lower Region of the Air, The Aristotelian Production of Hail examined. the drops of Rain that fall out of the middle Region being there congealed, by an Antiperistasis, and that it is only generated in Summer. But on the contrary, I have observed myself the greatest shower of Hail that ever I saw to fall in January, when the violence of the Frost had rendered the lower Region of the Air Cold; at which time a Servant to one of my Domestics told her Master, That she was led out of her way by an Ignis Fatuus, which, till she could follow it no further, she took to be a Candle, carried by another Person before her; where how the Nocturnal Air could kindle a fiery Meteor by its Coldness, and congeal Snow by its Heat, I profess I cannot understand: Besides were Aristotle's account true, I see not why they should never see it Hail at Alexandria and Pelusium, places in Egypt, where the lower Region of the Air is hot enough, and where it reins frequently; besides we have seen Grains of Hail larger by much than dreps of Rain, and at Lions in France the Virtuosos took Notice of a shower of Hail whose Grains were as large as a Tennis-Ball; and Bartholinus tells us, That he himself hath observed some so large, That they weighed a Pound; and to these I shall add, that tho' Aristotle asserts Hail to be generated in the lower 〈◊〉 and Snow in the upper, I have observed Grains of Ice, which contained Snow in the middle of them. The next Argument alleged in favour of Antiperistasis, and to be examined, is the Coldness of Cellars in Summer, and their Heat in Winter. And first, I deny that the Air in Cellars is cooler in Summer than Winter; since the reason why we feel it so, is only the Predisposition of our Sensories, which are comparatively warmer, by being enclosed in so warm an Air as that they are encompassed with in the Summer: But supposing, that not only our senses, but Weather-Glasses should inform us, That the Air in Cellars were Colder in the Summer than Winter; yet it might be accounted for without an Antiperistasis: for since there are several hot Effluvia sent up from subterraneal Parts, these restrained and kept from flying away in the Winter, may alter the temper of the Soil, and Subterraneal Waters; but when by the Heat of Summer the Pores of the Earth are opened, and way is made for the Avolition of them; upon that account the Superficial Parts of the Earth may be a little cooler. And for a like reason; we may think Cellars hotter in the Winter than the Summer, if we judge of them by the Testimony of our Senses; since we are not there affected with those Winds and External Agents of Cold, as in the open Air; and therefore to one that comes out of the open Air into them, they may seem Warmer. But that Cellars are Colder in the Winter than the Summer, when we estimate the degrees of them by Bodies that are not alike subject to Predispositions as our Bodies are; will appear from what follows. And first, two sealed Weather-Glasses being hung out in a frosty Evening, till they were both of an Equal temper; the one of them removed into a Cellar, in two or three Hours ascended five or fix Divisions; whilst that which remained in the Air rather descended than risen; but in the Morning that in the Cellar descended a little, so that the outward Air instead of Increasing rather Diminished the Heat of the Cellar: And Oil which in thawing Wether was usually Liquid, being placed in a Cellar in a frosty Night, was congealed; so that it would subside in other Oil: And I have further observed, That Oil that was froze in the Cellar upon a thaw risen instead of subsiding according to the Doctrine of Antiperistasis. And in Poland it is observed, That in the Winter small Beer freezes in the Cellars; and the like I have observed in England in a Cellar, which in the Summer kept Beer cool enough. And I am told, That in Russia, the Cellars are so far from being so Cold in Summer as in Winter, that they are forced to keep their Beer in the Summer in Water froze with Snow, and to dig their Barrels out as they have occasion. But tho' we should allow, That some Cellars and Vaults are warmer in Winter than Summer, yet it does not therefore follow, that it must be the Effects of an Antiperistasis; since it may be done by the Influence of Subterraneal fires; for which Reason deep Cellars are generally warmest: And it hath been observed, That the deepest Mines in Hungary are always the hottest; and tho' the upper Region in some measure seems Cold, yet that may easily be caused by the Predisposition of our Sensories, when out of the warm Air we find it comparatively Colder in the top of the Groove, and in our ascent Colder in respect of those Regions which are nearer the Influence of Subterraneal fires. And that the lower Regions are hotter than the uppermost, is not only evident from what hath been elsewhere delivered; but from what Archbishop Vpsal hath observed in the deep Mountains in Poland, from whence they dig Rock-Salt. And tho' the Heat of Springs in the Winter may be alleged by some as a cause of Antiperistasis; yet it is easily otherwise explained, since the Subterraneal Effluvia of the Earth, as well as the Comparative Coldness of the Air is sufficient to solve that Phaenomenon: And that the Antiperistasis is not so powerful in the Winter, as to have any effect on the Subterraneal Parts is evident; since Capt. James tells us, That he had a Well which remained unfroze all Winter; so that by breaking the Ice on the top they could get fresh Water: And it is attested by a Latin Author, That in or near the Island Hueena, wherein the famous Tycho built his Vraniburgum, there is one Spring which is not froze in Winter, and Olaus Magnus tells us, That near Nidrosia, one of the chief Cities of Norway, there is a Lake that in that Northern Region never freezes. And Josephus informs us of a hot Spring in Peru, from whence the Water's issue out boiling hot; yet a Spring which is just by it is Cold as Ice; so that the Nature of the Soil through which Bodies flow, may have a considerable stroke in altering the Temper of the Water. And to favour what I have said of the Reason why Springs steam in the Summer, I shall add, That it is observed, that our Breath as well as the steams of Issues are visible in the Winter; tho' not discernible in the Summer; and the very steams of a labouring Man have been froze on the outside of his waistcoat whilst he was working. And it's commonly observed, That the steams of a River are very apparent in the Evenings, tho' not discernible at Midday in Summer. And that the Earth is not only heated by those Subterraneal steams▪ but that those Meteors which we frequently see, proceed from Subterraneal Effluvia, will be rendered probable, by observing, That Miners usually foretell Storms and alterations in the Air, by the damps which rise in their Mines: And in Cornwall it is observed by the Fishermen, that those Sulphureous Exhalations which appear like fire up and down, generally precede considerable Storms. And the like hath been observed on the Coast of Ireland, when a black Cloud like a Barrel rising out of the Water, a violent Storm presently succeeded. And an Anonymous Writer tells us, That in Comitatus Zotiensis in Hungary, a Clift of Ground emits such steams, that Birds and Cats or Dogs being held over it are killed by the steams of it: And the same Author tells us, That near the City Buda, there are such hot Springs, that the River Danubius is not able to keep them cool; and he tells us likewise, that in the River Istroganum, they may discover hot Springs; by removing the sand with their feet. And I am informed by credible witnesses, That in the North of England there is a ditch which emits steams, which are inflammable; and probably there may be other places which emit such kind of Effluvia, and afford matter for fiery Meteors and Winds. And we are told, That not only in Muscovy, a Tract of Water a Mile long continued unfroze, when the rest was, and emitted hot steams: But Olaus Magnus tells us of a Lake Veter, which thaws with a considerable noise, That as well as the River Peking near China, which thaws in one Day, beginning at the bottom and so thaws upwards; and in these thaws it is observed, That they are foretold by a great boiling of the Water first under the Ice. And that such Effluvia being detained from flying away, and kept up in the Earth may contribute to the Heating of Cellars appears further; since in Muscow, when a Cellar hath been long kept shut; when first the door is opened, the steams will affect the Men so Powerfully, as almost to suffocate them. So that from hence it appears, That the Retention of hot Effluvia depend on a Constipation of the Pores of the Earth; and not on the Disposition of hot Vapours to fly away from their contrary; since we see that they have no such Disposition, the Vapours of a Well rather dispersing themselves in the Air than flying away from it. But to disprove the Doctrine of Antiperistasis, further, I shall add, That a rod of Iron, which had a piece of Iron fixed to one end of it, having that end made red hot, and quenched in Cold Water, the Heat did not recede into the other end, to avoid the Coldness of the Water. But a more convincing Experiment is, That a Weatherglass being suspended in a wide-mouthed Glass in Water, when that Glass was placed in hot Water, the Coldness of that in the wide-mouthed Glass, was so far from being driven upon the Weatherglass, that the Spirit of Wine did not in the least subside; but when the Heat of the External Water was diffused through the other, it manifestly rose. And this Experiment being tried with warm Water in the wide-mouthed Glass, and Cold Water about that, the Heat was not more intense about the Weatherglass; but when the Cold had diffused itself through the warm Water, the Spirit of Wine subsided. Postscript Tho' from what hath been said, it appears, That the Doctrine of Antiperistasis is not without Reason exploded; yet I shall suspend my Judgement, whether Cellars are warmer in the Winter than the Summer or not; since the learned Jesuit Zucchius tells us, That having suspended a Weatherglass 3 years in a Cellar, the Water would rise in the Winter and descend in the Summer. And another tells us, That he knew a Well Colder in Summer than Winter, yet I am far from believing this Observation universal; since what hath been said evinces the contrary; for, tho' the superficial Parts of the Earth are subject to vary in their Temperature, as the Wether influences them; yet Subterraneal Cavities than are very deep are neither hotter or colder in the Winter or Summer; and tho' Zucchius hath undertaken to measure it by the assistance of Weather-Glasses; yet since ordinary Weather-Glasses are subject to be influenced by the Gravity of the Air, as well as the Heat and Cold of it; and since some places are fuller of Subterraneal Vapours than others, and consequently the sudden ascent of Exhalations may presently increase the weight of it, I think the following Experiment made by the learned Maignan sufficient to balance what Zucchius hath delivered, and therefore I shall deliver it in the Author's words. Expertus ego sum (says he) Thermometro fidelissimo & a praecedente hyeme in sequentem aestatem prorsus invariato, instructo etiam tali aqua, nempe in hoc ipsum, ex praescripto Trebellii ita comparata ut non exhaletur, neque minuatur, expertus inquam sum, in supradictis optimis cellis Vinariis maximum, quod ardentissima aestate fuit, frigus non adaequasse illud quod ibidem erat brumali tempore, ut dixi— si quidem in Tubo vitrei Thermometri quatuor circiter palmos longos & in octo gradus Graduumque minuta diviso, aqua hyeme ascendit ad Gradus 7 cum semisse, aestate autem vix gradum sextum superavit, cùm tamen ad sensum multò magis vigerat frigus istud aestivum. CHAP. VII. An Examination of Mr. Hobbes Doctrine of Cold. Mr. Hobbes Doctrine of Cold. Mr. Hobbes in his Doctrine of Cold tells us, That the Air being put into an Expansive motion by the Beams of the Sun, it is beaten down upon the Surface of the Earth; where finding a resistance below, it spreads itself every way towards the Poles, and as the Parallel Circles grow closer towards the Poles, so the Air being straitened and more condensed causes a greater degree of Cold. To which he adds, That as the Air moves betwixt these Parallers, it rakes upon the Surface of Water, more or less as the Air is more or less straitened; by which means the Water not only tending towards its Centre by its own Gravity, but being also condensed by the rakeing Pressure of the Air, the Surface of it is first congealed, and then it gradually descends; and for a like Reason when Water is immersed in Snow and Salt, the Mixture melting those very Parts which lodged in the Pores of it, they rakeing against the sides of the Glass, give it such a motion, as when communicated to the Water contained in it causes it to congeal. And for a Reason not unlike the former, the Particles of Air contained in Clouds being in their descent squeezed out, rake the drops of Water in their passage, and so harden them. And the Reason why serene weather is Colder than rainy weather, he says is; because the force of the Wind is broken and dissipated by the falling drops; which Reason he likewise alleges, why Water in Wells is not froze, the Wind not being able to beat strongly enough upon the Surface of the Water. And as for the Reason why Ice is lighter than Water, he attributes it to Airy Particles, forced into it whilst it is congealing. But it may easily be urged against this Doctrine, Examined. that all congealed Liquors, instead of having their Parts pressed inwards, and so condensed, manifestly expand upon Congelation. And as for Animal Bodies, such an inward endeavour of the Humours, as his Doctrine supposes, is not requisite to produce a sensation of Cold; since a decrease of the motion of the fluids about our Sensories, or an Impulse made upon the sensitive Parts, by some alteration in the motion of the Blood and Spirits, or a turbulent motion of some excrementitious Particles hindered from flying away is sufficient; so some Hysterick Women perceive a Coldness on the top of their Heads and the Vertebra, when they are otherwise hot; and Avicen tells us, That the biting of some Vipers in hot Countries causes a sensation of Cold: And I know a Noble Man who feels an extraordinary Coldness upon him, when he is seized with a fit of the Stone. And an inward compression of the Parts of a Body is so far from being sufficient to produce Cold, that compression in some Bodies produces Heat. But to examine what he assigns as the Grand Cause of Cold, viz. Wind, which according to him is Air moved in a considerable quantity, and that either forwards only, or in an undulating motion. But against this Doctrine I have several things to offer. And first, that several frosts are begun and continued when the Wind is serene and calm; and that a gentle North-east-wind is much Colder than a boisterous Southerly Wind. Secondly, That the Wind which issues out of an Aeolopile is not Cold but Hot, tho' it moves more violently than the Wind which is blown from the Mouth. Thirdly, We have made it appear, That Water will freeze, tho' sealed up in a Glass, and tho' that Glass be enclosed in another, so that the Wind cannot beat upon it; and even an Egg frozen will be crusted over with Ice, when suspended in Water, so that the External Air cannot Effect it. And tho' he tells us, That all Winds produce Cold: Prosper Alpinus in his Medicina Aegyptiorum acquaints us, that he hath found the Winds in those Torrid Regions insufferably hot. And Marcus Paulus Venetus tells us, That the Winds near Ormus have been so hot as to destroy an Army of Men at once: And tho' some Winds put into motion feel Cold, yet that depends on the Predisposition of our Sensories, and the deeper penetration of that fluid into the Pores of the Body, in respect of which it hath a comparative Coldness; and that it is but a comparative Coldness is evident, since the same Wind blowing upon a Weatherglass affects it not at all; except sometimes by accident, when, by that means, some calorifick Atoms swimming in the Air, are driven away by it. And tho' Mr. Hobbes tells us, that all Winds cool by diminishing former Heat, yet we see, that Water actually Cold, becomes still Colder by freezing, where the Heat cannot be said to be diminished in a Body actually Cold before. But to proceed, tho' Mr. Hobbes says, that Wind is generated upon the Surface of the Earth by the action of the Sun; yet he tells us not how that Wind must produce Cold; nor does the motion of it towards the Poles help the matter, since we have shown, that motion in itself is not sufficient to produce Cold; and should he say, that the Coldness is derived from the Mixture of freezing Vapours in its passage, than those steams would rather be taken for the cause of Cold, than the Wind; and then I should ask him, Whence the Coldness of those Cold Vapours proceeded? Besides, since in his account of the freezing of Water, he says the Parts of the freezing Water will be raised in Congelation, I see not how it will happen; since Oil and several other Liquors are contracted by it, and I have not yet seen any one Instance in which Water was ever congealed by a Compression: Since when we enclosed Water in a Pewter-Bottle and beat the sides of it together, till the Water made its way out; we perceived not, that that powerful compression had in the least inclined the Water to Congelation. And tho' we should allow, that the Superficial Parts of the Water might be froze as Mr. Hobbes tells us, yet I see not how the Air can beat upon Water, severed from, it by Ice nine or ten Foot thick. Besides, I think it altogether inconceivable, how Wind by taking upon the outside of a Glass, should cause the Water within to freeze, since the freezing of Water is an action much different from the putting of the Glass into a trembling motion; besides we see, that Water will not be froze by the blowing of a strong Wind against the outside of a Glass, tho' it will when enclosed in Liquors where no Wind can come at it, and those two which are not subject to freeze themselves. And whereas Mr. Hobbes gives it as a Reason why some Wells frieze not, because the Wind hath not liberty to blow strong enough upon the Water, I shall add, that those Wells that are subject to be froze when Northerly or Easterly Winds blow, will freeze, tho' covered over and sufficiently guarded from the Winds; and in Cold Winters, whether the Wind blows or not. And, Whereas Mr. Hobbes tells us, that the lightness of Ice above Water, proceeds from the bubbles received into it whilst it is freezing; the Contrary is evident, since Water froze in a sealed Glass, will be plentifully stocked with bubbles as well as that which is frozen in the free Air. Postscript To conclude this History of Cold, I shall instead of some other Experiments designed for this Treatise, subjoin an Experiment elsewhere mentioned in the History of whiteness and blackness, viz. Take a piece of Cork and having burnt it, till it be reduced to a black Coal, and then having slacked it in fair Water, it will, by being mixed with Gum-water, form a black Ink, which you may write what you please with; which writing if it be interlined with a colourless Solution of Minium in Spirit of Vinegar, upon wetting the Paper with a sponge dipped in a fluid Liquor, prepared by mixing three Parts of Quicklime and one of yellow orpiment, and digesting them two or three hours in sixteen Parts of Water, the invisible Solution of Minium will exhibit black Letters, and the other black ones will disappear; but whilst this fetid Liquor is preparing, it must be well shaken several times, that the Quicklime and the powdered orpiment may the better impregnate it, and then the decanted and filtered Liquor must be kept for use. But besides this, there are several other ways of making Ink, which I could be glad to learn: And I myself have tried that Words might be writ with a Solution of Minium, which I could render legible by the help of the fire. CHAP. VIII. An account of Freezing made in December and January, 1662. By Dr. Merret. Several Experiments about freezing. THE following Experiments were made in Wether which was very frosty, continuing six weeks, yet not without some alternate Relaxations, in Stone-Windows exposed to the North and North-East-Winds. The Vessels in which they were tried were Glass-Canes of several Boars, Earthen and Pewter Vessels etc. Cold Water exposed to the Air in open Pans was froze in an hour, boiling Water in two; boiling and Cold Water mixed in ½; the Cold Water beginning to freeze at the top and and sides, but the other at the bottom; and when the Water was Cold at the top. The same succeeded, with Water thrown upon a Table, the Cold Water being first froze. A four ounce Vial with a Stem a Foot long and half filled, being exhausted of Air in Vacuo Boyliano, was almost froze as soon as Water exposed in an open Pan, and appeared white seeming to consist purely of bubbles. Water in which Arsenic was eight Months infused, congealed into a white Ice sooner than Water, and so did Solutions of all sorts of Vitriols; and sooner than Solutions of other Salts; except Alum, which froze into an Ice whiter than Milk, and stuck so fast to the Pan that I could scarce separate it. Sandever presently freezeth, but Eris sooner, and Kelp in less time than that; all of them forming white lumps of Ice. Salarmoniack frequently froze before the rest of them, but once after them. Two drams of common Salt dissolved in four ounces of Water was in hard frost congealed into a white Ice in about thirty hours. Stinking Sea-Water full of Salt being exposed in a Beer-Glass, was covered with a film of Ice as thick as ½ a Crown in twenty six hours; when froze it tasted Salt and smelled stinking; but when thawed it had lost the fetor: In four days more the whole was froze, but that in the bottom tasted sharper than the rest. The same Water in broad Pans was quite froze through in thirty six hours, and sooner in a Mixture of Snow and Salt; neither a strong Solution of Salt-Petre, no● Bay-Salt, nor Salarmoniack were froze in six days. But a Solution of Salt of Tartar froze in a little more time than Water; and being exposed in a Tube it began to freeze at the bottom, top and sides all once; whereas other Liquors frieze uniformly either at the top or bottom first. Salt-Petre in a Cold season was in twenty eight hours froze into a white Ice, which was mistaken for Sal-Prunel, and sparkled in the fire as that Salt usually does. A lixivium of it made with Copperas or Alum singly or mixed, set in Snow and Salt or Snow alone, was frozen in one Night. Salgem, tho' Snow and Salt were mixed with it, and tho' it were set in Snow and Salt, would not be brought to freeze. But Phlegm of Vitriol froze sooner than the Solutions before mentioned Oil of Vitriol is coagulated sooner than any of the afore mentioned Liquors, except Water; a large Tube being filled ¼ with it, and being froze, tasted of a strong Vitriolate taste; the coagulated Part, was of a paler colour than the other, and both being poured together in a Bottle, it became too hot to hold in one's hands, this coagulated Part remained unthawed a week after the rest of the Liquors; and another Tube of the same Oil being wholly froze, it subsided ½ an Inch below its station to which it risen again upon a thaw, but the other Liquors risen upon congelation. A flask of small Beer froze in thirty eight hours, but three Parts of Ale continued unfroze after six days hard Frost; but at four a Clock in the morning, the unfroze Liquor tasted much stronger and brisker than before it was froze; the Ice was less firm and fuller of bubbles than common Ice, and being thawed was very pale and of a quick Aleish taste. A Beer-Glass of Hull-Ale being exposed to the Cold in a Glass, in twenty four hours was crusted over with Ice, as thick as half a Crown, and that being taken off, it yielded another; and so successively, till the whole was froze; these Laminae were all of the same colour and taste, but the lowest was the most tender: This Ale would not freeze so soon as that which I exposed before. Hull-Ale hath a brackish taste. Claret exposed in a spoon, in thirty five hours was turned into a soft Ice, which had the Genuine colour and taste of Wine. In thirty eight hours Canary exposed in a spoon was covered with a thin film, which grew no thicker in four days. But neither Claret or Canary would freeze in Tubes or Bottles. Two ounces of Spirit of Wine exposed in a spoon all evaporated in twelve hours; but the same quantity of Brandy left about a spoonful of Ice void both of taste and it's Inflammable Quality; but being held betwixt my Eye and a candle it discovered several bubbles. An Ox and a Sheep's Eye were both frozen through in one Night, the three Humours being Opacous, hard and inseparable. The Crystalline humour was white like Whiting boiled, the waterish and glassy humour seemed to be made of flakes of Ice. Sheep's Blood exposed to freeze, the Serum was turned to Ice, which, being separated from the Blood and thawed at the fire, congealed a second time into a Membranous substance; but the Blood was not in the least froze. The Heart and Blood in the Vena Cava of a Dog and Cat exposed dead to the Air were both froze: Milk froze into white flakes, being soft and with few bubbles in it, and retaining the proper taste of Milk. The yolks and Whites of Eggs were froze in one Night, they thaw best by lying on Newcastle Coals or in a deep Cellar: I am told that Eggs, tho' they have been froze, will produce Chickens-Eggs held near the Surface of the Water when froze will acquire a crust of Ice on the outside, the inward Parts of it still remaining froze; and if those Eggs whilst froze, be poch, they will be very tough. An Egg and an Apple being suspended two Foot deep in a Cistern and taken up after twenty four hours, tho' both of them were full of Ice within, yet neither of them had contracted Ice on the outside. Horse-Radishes and Onions froze, yet Beer in which Horseradish and Scurvey-Grass are infused will not freeze so soon as strong Beer without them. Oranges and Lemons froze, have a hard and tough rind, and lose their genuine taste; and when thawed they soon become rotten: Apples Cut in the middle, will have a thin Ice on both plains, which may be discerned by a knife or the touch. The skins of these Apples soon turn brown, and they begin to corrupt there. Oil exposed looked like Butter melted and coagulated again; but in Caves and Cellars, it would never appear more than Candied. White Wine-Vinegar froze in a Tube without apparent bubbles. Whatever hath a watery humour in it will coagulate. But what will not, the next Paragraph contains. Spirit of Wine, Aq. Mariae, Coelestis &c, and Canary in large Vessels, Soap-Boilers Lees, Spirit of Salt, Vitriol, Salt-Petre, Aqua fortis, Spirit of Sulphur, and Spirit of Soot will not freeze, but the two last afford a Precipitate; the first of the colour and taste of Brimstone, but not inflammable; the latter a yellowish powder more bitter than the Spirit and inflammable. But tho' these Spirits would not freeze, yet being mixed with twelve Parts of Water, all of them froze except Spirit of Salt, Nitre and Aqua fortis: I am told that one having dissolved Ice in the North Seas found it Salt. As for the figures of Liquors froze, Alum appeared in lumps, Salt-Petre, Tartar, Milk, Ale, Wine and Salarmoniack in plates. And other Liquors which composed a soft Ice, seened to be composed of Globuli adhering to each others. Water, Kelp and Frits resembled the fibres of an Oaken leaf, the interstices being filled up with smother Ice, and the middle Fibres, as in Plants, appeared larger than the others, and made acute Angles at the lesser end of the leaf. But as for the figures of frozen Urine, those having been accurately described by the curious Mr. Hook, I shall pass that part of my task by. I took the Salts of Rosemary, Rue, Scurvey-Grass, Mint and Plantain, and putting ½ or ¾ of an ounce of each into ½ of a pint of their distilled Waters; the Rue and Plantain being sealed up, none of them froze resembled the Plants they belonged to; but the Aromatic Waters were much enriched in their scents, especially the Rosemary; Kelp froze represents the leaves of Alga Marina. A Recipient full of Water being froze and the top of the Ice broke, there appeared a Cavity within, which was thick set with Plates of Ice from which Stiriae appeared on each side like the Teeth of Combs, some of which stood at such a distance that I could put my finger betwixt them. A flask full of Water being froze it appeared full of bubbles like tailed hailshot, the sharp points of all of them pointing upwards. They had Cavities which would admit a Pin into them and might be discerned in the Ice, appearing like black spots: And in the middle of the Ice was contained a Cavity filled with Water in which were several of these bubbles imperfectly form. All the Liquors I made Experiments with, did sensibly rise above the mark, before they froze, and more after congelation. Vinegar and Urine risen ½ an Inch, and Lees made of Salts of Rosemary, Kelp and Frits, about ½ of an Inch. Solutions of Alum and Copperas less, and Saline Liquors in general less than Water, which risen a full Inch, and small Beer in a narrow Tube four Inches. Oil of Vitriol alone subsides below the mark, hot Water subsides till it is cool and then rises again. Water being froze in Beer-Glasses, rises up and forms solid Triangles, but the rising of it is more visible in narrow Glasses: Ice in a flask risen four Inches above the Water-mark, and hung two Inches out of it, but in a Bolt-head it risen five Inches above the Water-mark. If Glasses be filled about ⅔ full they seldom break. Round Spherical Glasses usually break uniformly. A Bolt-head being filled up to the neck with Water, the top which was twelve Inches above it, was sealed up; upon which the Water being froze, was raised three Inches into the neck; and the Glass breaking in the thinnest Part, from that point, several Lines ran as from a Pole to the Meridian, but none of them went round the Glass, nor were they all of the same length: In a flask cracked in many places the cracks were irregular: Glass Bottles and stone-Jugs, kept little order in breaking, and Metals none at all, but Woods cleave with the Grain. Two oval Boxes, one of Box and another of Maple, containing each two ounces, were filled full, and by the Frost in one Night were cracked from the bottom to the top. A Pepper-Box of Latin, had its neck broke off and the joints at the bottom loosened. Lead-Pipes above ground were broke in many places, and some that lay a foot under ground: Brass-Locks and Barrels of Pumps usually break with the Frost. A Copper-Box of the shape of a Pear was cracked the fourth time it was froze. The Cylinder of a silver Ink-horn bore the Frost, but a silverball was considerably extended by the Frost. Tobacco-Pipes and Earthen Ware were burst with the Frost, and Tiles of Houses and stone-Buildings scale upon a thaw; for which Reason the North side of Buildings first decay. Alabaster and Marble that have chinks in them usually break with the Frost, but solid Marble does not, nor does Frost affect those stones or Bitumen which will bear a Polish. Ice laid on a Table, and having Salt strewed upon it, it stuck so fast that it could not be separated without being broke in pieces; and the Salt made its way through the Ice down to the board; but if Salt be strewed betwixt the Ice and the board, it will not be froze to it but thawed. The following Salts cause not so firm an adhesion as common Salt, viz. Kelp, Sandever, Sal Indus, Gem, Prunel, Armon. and Pot-ashes. A nail held betwixt my lips could not be removed without difficulty and Pain. A Tincture of Cochineel with Spirit of Wine, and another with a little Sea-Salt Water, being froze throughout, retained an equal colour in all Parts, and so did a Tincture of Mades-weed, and Indigo. A Decoction of Soot was froze without any Concentration; yet Mr. Hook, a worthy Fellow of the Royal Society, hath observed the contrary effect. Eggs and Apples-froze differed not in weight, nor do Bodies weighed in sealed Glasses. Frost renders Wood, Iron, Steel and the Bones of Animals, more friable in frosty Wether; especially in those that are tainted with the Lues Venerea. Frost preserves Bodies from Putrefaction, and confirms the Tone of Animals, and fattens some; it clears the Air, so that musty Stone-Bottles being filled with Water and froze, after a Thaw were very sweet; it likewise destroys Animals and Vegetables, so that in Greenland nothing but Glass grows, as also in Nova Zembla. The qualities of Ice. As for the qualities of Ice, it is slippery, smooth, hard, firm and strong, diaphanous, interposed betwixt the Eye and a Candle, appears in many round Circles, from whence proceed Rays, in the form of a Star, a quarter of an Inch in diameter. I have seen the Ice in the Thames eight Inches thick, and in Garden-walks the Earth froze near two Foot thick, but in rich Soils it did not penetrate above a Foot and a quarter Ice generally swims, but I have seen Snowballs, compressed and moistened with Water, sink Congealed Oil of Vitriol sinks. Ice is colder than Water, and that quality is increased by adding Salt or Snow. It hath no smell, but checks that quality in other Bodies. It yields both Reflection and Refraction. North and North-east Winds, the absence of the Sun, the highest Parts of Mountains, a mixture of Snow and Salt, promote freezing. Water falling upon Ice or Snow freezes, and a mixture of beaten Ice with Sea-Salt, Kelp, Alum, Vitriol, or Nitre, and Oil of Vitriol, will promote freezing; and if Water be set upon such Mixtures, it gins to freeze at the Bottom; Salt Petre dissolved in Water, and agitated in a cold Season, turned not the Water into Ice. A Bolt-head being placed in Snow in a Pan, tho' the Pan was set on the Fire, and thawed gradually, yet the Water in the Bolt-head froze not. Water frozen in Pans, being set on Newcastle Coals in a Cellar, and likewise on Sand, and on the Earthen Floor, they thawed in the same order; and so did Eggs and Apples. A Syphon may be made of Ice, through which Water will run very fast. Another use which may be made of Ice is for Refraction, of which Mr. Hook hath given a learned Demonstration. Having form Ice into various Figures, the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 were the same as those mentioned by Dioptrick Writers. We may likewise make a Speculum of it, by holding a piece of Paper behind it; The Learned Bartholinus delivers the following Propositions of it. 1. That the more subtle distilled Spirits gain a clear splendour and elegancy from Snow placed about them. 2. The Rays of Snow newly fallen, glitter and dazzle the Eyes: by reason of the multitude of Globuli, by which they are reflected. 3. A Cabbage putrified in that part which was above the Snow. And I have observed great Housleek, or American Aloes destroyed by Cold in an upper Room; and Sea-Onions as well as common Onions will be putrified by the Cold. 4. Snow yields Vapours plentifully, when melted by the Sunbeams. 5. It melts and falls off from Ivy. 6. It contains a little Earth in it; which I have found true by Evaporation. 7. Viscosity with Softness is greater in new than old Snow, 8. Watercresses and Scurvygrass will grow under Snow in Gardens; but I am apt to believe they are at a perfect stand, the nutritious Juice being congealed. 9 Air is included in Snow. Whites of Eggs being beaten into a frothy Consistence, and this being laid on a Trencher, soon appeared to be Snow. A Pail being filled with warm Water, and Hair, Moss and a piece of Rosemary hung over it, the rising Vapours sticking to them form a Hoar-frost, and the like is observed on the Beards of Men, and the Hairs of other Animals. 10. Snow abounds with Fat. 11. Snow with Ice swims on Water. 12. Snow-water boils Meat sooner, and makes Flesh whiter. I could not find that this holds in Fish or Flesh. 13. Snow newly fallen hath no taste, but when it hath lain on the Ground, it bites the Tongue. This I could not discern. 14. Worms are sometimes found in Snow. I could never observe this, 15. A strong Salt may be drawn from Snow by a peculiar Art. 16. After much Snow plenty of Nuts. It sometimes fails. The Duke of Tuscany distilled a Spirit from Wine, only by putting Snow upon the Alembick; and the Duke of Mantua had a Powder, which would freeze Water in the middle of Summer. Weather-Glasses being framed after the Italian mode, and in part filled with tinged Spirit of Wine; I placed one of them in a Northwest Window, and the other in Mr. Pullyn's Warehouse under St. Paul's Church, in the warmest place; the Spirit of both, when they were settled on the fifteenth of Octob. 62. having the Altitude of three Inches; and when that in my Study-Window was depressed an Inch, that in the Cellar received no manifest alteration: But when the other was depressed two Inches, it subsided ¼ of an Inch, which was the lowest Station it subsided to all Winter; and in April following it risen not above the three Inches it first stood at, above ¼ of an Inch, tho' that in my Study was raised four Inches ¼. In this Cellar, Liquors that were froze above Ground, would be thawed in the Morning, The Spirit in the Glass above ground subsided into the Ball after two days hard Frost. Whence it appears, that Cellars are not hotter in Winter than Summer. One thing observable was, that the tinged Spirit had lost its Colour in the Cellar. In January, a Pint-Bottle of Claret, a Glass-Cane filled with Canary, a Solution of Sal Gem. train-oil, and the Oil of fructus Musae, in a Night's time were all froze, except the Shall Gem, in the bottom of which chrystallized Salts appeared. The Oil of the Fruit became very friable, and of a milky-white Colour, but the Train Oil only lost its fluidity, and became of the consistence of soft Grease. And the same Night, a Bottle of Rhenish Wine, and another of strong White-wine, were for the most part froze, the Ice tasting weaker than the Wine; but the Wine being several times froze and thawed again, neither lost any thing of its Colour, Taste, or Strength. Mr. Hook showed me an oval Glass, which had at one end a narrow Cane an Inch long, in which Water tinged with Cochineel being froze, the Ice on the outside was colourless, but in the middle of a deep Tincture; and I have observed the like in Flasks containing the same Tincture froze. Flesh, Fish, Eggs, and Apples, being held near the surface of Water, and immersed in it, are crusted over with Ice; and I have observed that Mortar and Plaster of Paris will freeze. I have seen Ice three Yards thick on the Banks of Thames, the Water which flowed successively over the Ice being froze, and gradually thickening it; and I have froze a whole flask full of Water, by gradually pouring it into a Pan; which confirms what Olearius says of making huge heaps of Ice to preserve Bodies. Tho' my Lord Verulam tells us, that Eggs and Apples covered with a wet Cloth will not freeze; yet I have not observed any difference betwixt them and others. Oils of Animals, and vegetable Oils by Expression, subside. Syrups frieze not. Cold affects not Lodestones sensibly in their Operations. Having exposed distilled Waters of Plantain, Poppies, black Cherries, Nightshade, Scurvygrass, and Horseradish to the Cold, in order to make a Standard for Weather-Glasses, I observed that the Black-cherry-water was froze first, and the Horseradish and Scurvygrass Water's last. The best way to discover when Liquors begin to freeze first is, by drawing a Pin through the surface of those Liquors. CHAP. IX. A new Frigorifick Experiment, showing how a considerable degree of Cold may be suddenly produced without the help of Snow, Ice, Hail, Wind, or Nitre, any time of the year; comunicated in the Transactions of July 18. 1666. Cold produced by a mixture of Sal-Armon. and Water. IF a pound of powdered Sal Armoniac be mixed gradually with three pints of Water, and the Liquor be stirred with a stick or a Whale-bone; whilst the Salt is dissolving, it will produce a considerable degree of Coldness; which will not only be sensible to the touch; but if it be contained in a Silver Tankard, the outside of it will be covered over with a multitude of little drops of Condensed Vapours, as high as the Mixture reaches; and if some of it be quite wiped off, before the Mixture hath lost its virtue, it will again be covered over with dew. And if the Ball of a sealed Weatherglass be immersed in it, the tinged Liquor will presently descend, lower than it did in common Water, and upon a Removal of it into the Air again or common Water, the spirit will manifestly ascend. And this Coldness is more or less lasting, as the seasons of the Air contribute to its Coldness, and as the Quantity of the Salt in proportion to the Water is greater or less; or as it varies in Goodness; or as the Salt is put in in grosser Powder, and more leisurely. And the degrees of Cold may easily be discovered, by frequently immerging, and removing a Weatherglass out of it into Water, and from the latter into it again. Whether Shall Armoniac mixed with Sand or Earth will cool Drink better than without, when the Mixture is sprinkled with Water, I have not yet tried. But I have found the aforementioned Mixture cool Liquors conveniently enough after Midsummer. March 27. A sealed Weatherglass being immersed in Water, the Spirit that rested at 8 1/● Inches, descended to 7 ●/8; and then the Sal-Armon. being put in, within a quarter of an hour, it descended to 2 1/● ⅙ Inches, and before that time, it began to condense the Vapours on the outside of the Glass. And when the frigorifick Mixture was coldest, Water placed thin on the outside would be froze in a quarter of a Minute. About 3/● of an hour after the Salt was put in, the tinged Liquor being removed out of Water into it, subsided an Inch below the freezing Mark. At 2 ½ hours after the first Solution it was at 5 ½ Inches, or 4 ¾, which Mark the Liquor stood at, in hard and lasting Frosts in the Winter. Three hours after the first Dissolution, the Liquor stood at the uppermost freezing Mark. In trying of which Experiment it was observable, that some Water being shed, it froze the Cucurbite to the Table it stood on. In another Experiment, before the Weatherglass was put in, it stood at 8 ⅛, but when immersed in Water it sunk to 7 ⅝ or 6/8; in half a quarter of an hour in the frigorifick Mixture it subsided to 7 ¾, and in an hour below 5, and consequently within a quarter of the lowest freezing Mark. Salt which once hath been dissolved, may, by being crystallized in an Iron Vessel, be fit for use again. So March 29. the Thermoscope, which in the Air stood at 8 ⅞, in Water subsided to 8, and in the frigorifick Mixture made of Salt, twice used before, it subsided to 4 Inches; but upon an addition of fresh Water, it risen gradually. CHAP. X. Of the positive and privative Nature of Cold. Arguments alleged in favour of its positive nature answered. BEfore I proceed to enumerate what Arguments may be alleged either for the positive or privative Nature of Cold, I shall briefly intimate, that the word Cold may be either considered in reference to the effect such Bodies have upon the Sensory, or upon other Bodies: If in the latter, then in frosty Wether the Sun may be said to warm the Air, because it enables it to melt the Snow, and thaw Ice, as on the contrary, warm Water is said to be cold in respect of a Hand that is much hotter. The first Argument. But to pass on to Arguments in favour of the positive nature of Cold: The first Argument alleged is, The considerable Effects it hath both upon the Sensory and other Bodies; so that we may sum our Argument up in the words of Gassendus. Two sunt frigoris effectus, quales habere Privatio, quae actionis est incapax, non potest. To which it is answered, That Heat and Cold depending only on a greater or less degree of motion of the parts of Matter, than those about our Sensory; and all Perceptions being carried to, and distinguished in the Brain, and being various, as that Motion is different, and it being likewise considered, that when one Body communicates Motion to another, it loses of its own; it will follow, that when I take a piece of Ice into my Hand, and it is dissolved by the motion communicated to its Parts, the motion which the Humours in my hand lost, by putting those of the Water into motion; induces a sensation of Cold; and consequently there seems to be a privation of that motion which before caused Heat. The second Argument. Another Argument alleged for the positive Nature of Cold, is this from Gassendus. Cùm per hyemem immittimus manum in labentis fluminis Aquam, quod frigus in ea sentitur, non potest dici mera privatio, aliudque prorsus esse apparet, sentiri aquam frigidam & sentiri non calidam. Et fac eandem aquam gelari, sentietur haud dubie frigidior; an dices boc esse nihil aliud quam minus calidam sentiri? Atqui calida jam antea non erat, quomodo ergò potuit minus calida effici? To which it is answered, That our Sensories may mis-inform us; as when a Stick is partly immersed in Water, should we judge of it by what appears to our Senses, we should conclude it broke; but our Reason rectifying the Error of our Senses, we are satisfied it is not: Besides Sensations may depend on alterations in the internal Parts, as well as on the impressions of outward Objects, as in Hunger, Thirst, Coldness in Agues, and Titilation upon venereal Thoughts; besides which Argument, that urged against the former Objection, may be offered against this. And since Water is not so cold as Ice, it may in a Philosophical Sense be said to be comparitively warmer, and tho' in respect of the Humours of our Body it be cold, yet by the same reason we might conclude warm Water cold, when the Hand is removed out of hot Water into it. A third. But in favour of the positive nature of Cold, it is further offered, that Cold is sometimes introduced into Bodies not hot before. To which it is answered, That since Fluidity consists in an agitation of the insensible Parts of a Body, and Heat in a tumultuary one; those Bodies into which Cold is introduced by Congelation, differ whilst they are fluid, only in degrees of motion from Heat; and even when Water is froze it is not absolutely and perfectly cold; since the Ball of a Weatherglass being immersed in a Glass of Water, and taken out when the Water was froze about it (the Glass having been before tallowed over, to make it part with the Ice) the Ice being broken off the Ball of the Weatherglass, the Air which was colder caused the Liquor to subside. And that there may be sensible Perceptions of several degrees of Privation of the impressions of outward Objects appears, since we perceive a sensible privation of Light when the Moon is eclipsed nine Digits, and a more sensible one when it is totally darkened. But tho' I argue for the privative nature of Cold, yet I would not be thought to mean, that an absolute Privation of Motion is the cause of it, and by which it is affected; for I rather think them the occasion, than the efficient cause; the motion of the Blood and Humours being differently modifyed, upon a privation of their motion, and consequently a different Sensation impressed upon the Sensory; and that a Privation of the motion of some Parts of matter about our Sensory may occasion a new Determination of the Motion of those Fluids, may be inferred from easy Observations; for a Tennis-Ball is variously determined in its motion according to the Angle of Incidence upon another Body; and tho' the Arches of a Bridge be quiescent Bodies, yet by throwing the Water together, they render its Stream violent enough to turn Mills; and even the rapid motion of a Bullet may receive a new determination of its motion, by striking upon the surface of the Water, if, when it was first discharged, it made a sharp Angle with the Water, so that its Angle of Incidence might not be too blunt; and that various effects may ensue a Privation of some principal cause of former Events, appears further from observing, that by stopping the motion of Water, a Mill presently ceases to move, tho' no positive violence be offered to it: And upon a relaxation of the violence of Wind, all that was performed by the Mill presently ceases for want of Wind: And in Paralytic cases, a viscous or narcotic Humour obstructing or disaffecting one part of a Nerve, so that Spirits cannot freely circulate through it, occasions several odd and terrible Symptoms: And Animals included in an Air-Pump die barely by a privation of Air, tho' nothing else is present to disaffect them. And even Infects, tho' void of motion upon a privation of Air, yet when it is again let into them, they move about as the advantages of their Species enables them; so that from what hath been said it appears, that a privation of the Agitation of the Humours may occasion a contrary, and probably the effects ascribed to Cold. A fourth. The next Argument alleged by Gassendus and to be considered is this. Fac manuum immitti in aquam nunc calidam, nunc frigidam, quamobrem manus intra istam, non intra illam refrigeratur? An quia Calor manus intra frigidam retrabitur, manusque proinde relinquitur calida manus? At quidnam calor refugit, quod intra frigidam reperiatur nonne frigas? At si frigus est Tantum Privatio, quidnam calor ab illa metuit? Privatio sane nihil est, atque adeo nihil agere, unde ejus motus incutiatur, potest. But without supposing insensible matter to be in the least capable of proscecuting or avoiding what is hurtful to it; this Objection is easily answered; for the Reason why warm Water feels hot; and cold affects us upon immerging our hand in it, is, because the Parts of the one is more, and the Parts of the other less agitated than those about the Sensory, and the motion of Humours about our Sensory; being increased we feel a hot sensation; and a cold one upon a Privation of that motion. A fifth. And tho' it be urged by some in favour of the positive Nature of Cold, that Water is froze by externally applying to the outside of a Glass a Mixture of Snow and Salt; yet to show that Argument proves not that Cold acts positively, I shall add the following explication of des Cartes. Quia materia subtilis, partibus bujus aquae circumfusa crassior aut minus subtilis, & consequenter plus virium habens, quam illa quae circa nivis partes herebat, locum illius occupat, dum partes nivis liquescendo partibus salis circumvolvuntur. Facilius enim per salsae aquae quam per dulcis poros movetur, & perpetuo ex corpore uno, in aliud transire nititur, ut ad ea loca perveniat in quibus mortui suo minus resistitur, quo ipso materia subtilior ex nive in aquam penetrate, ut egredienti succedat, & quum non satis valida fit, ad continuandam agitationem hujus aquae illam concrescere sinit. And in a similar manner Calces or Precipitates, or other Powders, are dried by being placed on a piece of Paper, not that that acts positively upon them, but imbibes the moisture. And I have seen a Cold Liquor acquire a hardness, its moisture being imbibed by a piece of Bread immersed in it; as also Spirit of Wine dephlegmed by a Mixture of Salt of Tartar, without so much as Heat, the Aqueous Parts finding a more ready and easy passage into the Pores of the Alkaly, than through the Spiritous Liquor. And I know a saline Body, which when incorporated with Water, the Water will leave this a consistent mass, and be imbibed by the Spirit of Wine. And for a further illustration of the Cartesian Explication, I shall add, that Camphire by floating upon Aqua fortis will become a fluid Oil, and continue in that form till the subtle Spirit, which, by pervading it, kept it fluid, flies away and evaporates; for being put into Water, the Spirit leaving the Camphire, and being imbibed into the Pores of the Water, it becomes a consistent mass again, which, that it depended not on the Coldness of the Water was evident, since the same would happen on warm Water. But tho' Cold should depend primarily on the influence of frigorifick Atoms, yet since those by acting on the Body cooled, may produce their effect by expelling calorifick Atoms, the privation of those calorifick Atoms, is the cause of freezing; so tho' a Bullet kills a Man, yet the issue is a privation of life; and when a Room is darkened by extinguishing the light, the darkness depends on the privation of light. A sixth. The last Argument of Gassendus is this, Tametsi multa videantur ex sola caloris absentia frigescere, nibil ominous nisi frigus extrinsicus inducatur, non tam profectô frigescere quam decalescere sunt Censenda. Esto enim Lapis, Lignum, aut aliquid aliud, quod nec calidum nec frigidum sit, id ubi fuerit ad motum Igni calefiet sane, at cum deinceps calor excedet, neque frigidum ullum circumstabit, non erit cur dicas ipsum frigefieri, potius quam minus calidum fieri rediere in suum statum. But to this it may be answered, that if we speak of Coldness with respect to sense, I see not why any Body that grows hot by the action of the fire may not be said, to grow Cold rather than Decalescere, since Heat being only too brisk an agitation for our Sensory, when upon a removal of that Cause, and a declining of that motion, it became less agitated than the Humours about our Sensory, we may not then say it grows Colder and Colder till it become Ice. But to conclude this Chapter, I shall add, that tho' I have offered these Arguments against Gassendus, yet I shall wave determining the Controversy till further satisfied in some Speculations, and in the Phaenomena of some Particular Experiments; besides I would first know, from those that would have Cold to be a positive Quality, whether and on what account those little fragments of matter are Cold, Whether their frigorifick Atoms have weight? As also what is their Texture, and whether that Quality may be destroyed; and whether they be primitive Bodies or not? And why Coldness ensues the Mixture of two warm Bodies. And in order to the solving of some of which it would be requisite to inquire, how Water comes by its expansive force upon congelation? And since Cold is a Privation of motion, why upon the Mixture of certain Bodies Cold ensues, tho' their Parts be thereby put into motion. CHAP. XI. Two Problems about Cold. An attempt to measure the great expansive force of freezing Water: Of the Production of Cold by the conflict of Bodies appearing to make an Ebullition. The first Problem. THE first Problem I shall propose is; how upon the Mixture of two or three Bodies, there should ensue a great and tumultuary agitation of small Parts, and yet even during this conflict, not any sensible Heat; but a considerable degree of Cold be produced. Concerning which I shall only propose the question, whether local motion be not Generical; and whether the figure and size of Parts variously moved may not be able to cause a sensation of Heat, and when variously modified, a sense of Cold; or whether the sense of Cold depends not on some frigorifick Atoms which are let lose in the Ebullition and affect the Sensory, which would otherwise perceive a hot sensation by the effects of the motion of those Parts, with which cold Aoms are mixed, and which they overpower. The second Problem. The second Problem is, Whence the vast force of freezing Water proceeds? For since Cold depends on an Imminution of local motion; it is not a little strange how it should be able to break resisting Bodies, which require local motion to separate their Parts. And tho' Gassendus tells us, that they proceed from the ingress of frigorifick Atoms; yet till Glaciation succeeds, notwithstanding Water grows colder gradually, it subsides and does not expand: And Spirit of Wine, and Chemical Oils, the greater degree of Cold they are exposed to contract the more; and some Oils even when coagulated are condensed instead of being expanded. And as for what the Cartesians offer for the removal of these difficulties, it may well be questioned how their Eel-like Particles being relaxed and their spring weakened, they should be able to expand in spite of Opposition. So that considering that Water when expanded is full of bubbles, I was apt to suspect, that the Air contained in them contributed to the effect, and that a constipation of the Pores of Water might give them a springiness. The great expansive force of Water froze. To try the expansive force of freezing Water, we conveyed a Bladder full of Water into a Brass Cylinder, and fitting a Plugg to it, upon that we placed a flat Board to hold Weights on, and then the Cylinder being encompassed with a frigorifick Mixture, upon the freezing of the Water, in one Experiment the Plugg raised 115 pound, weight and in another 100 pound Averdupois, and in a third 254 pound weight. Three saline Bodies, each purified by the fire, being mixed together, Of the Production of Cold. produced a cold Effervescense with a hissing noise and a considerable Intumescense. And in the mean time the Glass which contained it would grow colder than before, and gather a Dew on the outside, which would reach as high as the Mixture; but on the concave bottom of the Glass there was no Dew, that being not sufficiently exposed to the Air; so that the Mixture could not be supposed to sweat through the Pores of the Glass, since it tasted not in the least of saline Ingredients: But lest our Senses should misinform us of the degrees of Cold, in this Mixture, we at another time immersed a Weatherglass, in which the Liquor subsided above four Inches lower than in common Water. Tho' the Acid Liquor itself, being kept all Night in a Room with Water, was of the same temper with it, which appeared by a Weatherglass immersed in both successively. And the Salt itself being cast into Water scarce made it sensibly colder; nor did the Glass wherein this Salt was kept disclose any remarkable degree of Coldness. And even the frigorifick Mixture itself, when the Ebullition was over, appeared not colder than common Water in a Night's time; so that the Coldness depended purely upon the Texture of the fermenting Liquor. And to this I shall add, that tho' I made use of a Spirit that was drawn off at the same time with this Salt, and which in the Judgement of my senses appeared to be of the same kind, yet instead of a cold Ebullition, it produced a Lukewarm Heat. And to these I shall further subjoin, that tho' the Liquor above mentioned would produce a cold Ferment with the dry Salt, yet with the Spirit it grew warm; tho' some of the same frigorifick Spirit kept warm by the fire till the Liquor in the Weatherglass risen, yet upon the injecting of some of the dried Salt it would be manifestly depressed. Nay, though the Spirit and Salt were both warm, yet upon their Mixture they would produce a manifest Coldness. And to this Experiment I shall add, that Salt of Tartar mixed with Spirit of Vinegar produced, upon their Ebullition, a degree of Coldness greater than that of Water, and when a Weatherglass was removed out of Water into it an hour after the ferment, the Spirit was depressed about half an Inch; tho' Salt of Pot-ashes mixed with Spirit of Vinegar produced Heat, as appeared by the same Weatherglass successively immersed in either. CHAP. XII. Of the Mechanical Origin or Production of Heat. Of the mechanical Production of Heat. HEAT being a quality whose nature seems to consist in a mechanical Motion of the Parts of the Body said to be hot, it may be requisite to note, that the three following Conditions are necessary in modifying that Motion. First, That the Motion be more rapid than in Bodies barely fluid; so Water becomes hot by an increase of the motion of its Parts, which argue their vehement motion by dissolving Butter, and rising in the form of Vapours: Which effects are more conspicuous as the degree of Motion is greater or less. Another Instance to show that the Parts of hot Water are in a more violent agitation than those of cold, is in Water cast upon a hot Iron; for they presently acquire such an additional Motion from that hot Body, that it hisses and boils, yielding Steams copiously. But a stronger instance of the vehement Agitation of the parts of hot Bodies is in actual Flame, since they move so impetuously as to dissolve and shatter whatever lies in their way. A second Condition requisite to render a Body hot, is, that the motion of its Parts be variously determined; which variety of Determination is apparent in Fire, which produces the same effects on the same Bodies, whatsoever is their Situation in respect of that Fire; so a red Coal melts Wax, whether held above, below, or on one side of it; and that a variously determined Motion is requisite, appears, if we observe that the rapid motion of Water in a River which is only one way, contributes not to the increase of its heat. A third requisite is, that the Parts in such a Motion should be very minute, so as to be insensible; since it is manifest, that tho' Sand be put into a violent motion, it acquires not a heat by it. This account of heat being considered, it will appear, that a Body may become hot as many ways as it is capable of having its parts put into such a Motion: To illustrate which Observation, I shall subjoin some instances of the Production of Heat several ways; as first by an effusion of Oil of Vitriol upon Salt of Tartar, Aq. fortis upon Silver. But to pass over these common Instances, I shall proceed to some not so frequently known, having first taken notice of the Heat which succeeds an effusion of cold Water upon Quicklime, which Phaenomenon, tho' it be commonly held to be an effect of an Antiperistasis, upon the enclosure of the Lime in cold Water, yet that the effect is produced by another cause appears, since the like succeeds if hot Water be made use of instead of Cold; and further, because, tho' Oil of Turpentine be poured on it cold, no such Effect follows. EXPERIMENT I. Tho' Helmont ascribes the Incalescence of Quicklime upon an Affusion of Water, to a conflict of an Alkalizate and an acid Salt, set at liberty by being dissolved in the Water; yet since no such acid appears to be latent in Quicklime, the account is unsatisfactory: For I might as well suppose an Acid latent in other Alkalies, in as much as Salt of Tartar mixed with Water, either in the Palm of ones Hand or in a Vial, affords a sensible Heat. EXPERIMENT TWO, III, IV. Others think that the cause of the Heat of Quicklime proceeds from some fiery Empyrumatical Atoms lodged in the substance of the Stone, when calcined, and set at liberty in the form of Effluvia; but this Hypothesis is not without some difficulties, since no such Heat succeeds an affusion of Water upon Minium, or Crocus Martis per se, tho' their increase of weight argues that they are stuffed with fiery and metalline Particles: To which I shall add, that I knew two Liquors, which being several times separated, and reconjoined without addition, did at each Congress acquire a sensible heat; so Salt of Tartar several times freed from Water, The effects of a mixture of Salt of Tartar and Water. will produce Heat when mixed again with that Water; which shows that the violence of the Fire is not requisite to impress upon all calcined Bodies that will heat with Water, what passes for an Empyreum. And this Phaenomenon I am apt to believe proceeds from a disposition of the Texture of the Salt being stocked with store of igneous Parts, which upon an ingress of Water pressed into the Pores of the Body, by the weight of the Atmosphere, are apt to break the Texture of that Body, and to put them in motion, so as to produce a sensible Heat. And that the Ferment depends upon the peculiar Texture of the Salt, I am persuaded, and a constipation of the Pores of it; since Sal-Armon. dissolved in Water and boiled to a dry Salt, was not so much impregnated with fiery Parts, as to cause a Heat upon its mixture with Water again, but a considerable degree of Cold; and tho' one would expect a greater cognation betwixt the Particles of fire adhering to Quicklime, and Spirit of Wine wholly inflammable; yet the latter poured upon the former did not produce any sensible incalescence, or dissolution of it; and when this Spirit was soaked into it, I poured Water upon it, without perceiving the least Heat or the Lime broken, till within a few hours after; so that the Spirit being sucked into the most capacious Pores of the Lime, and associating with the Water, rendered it more unfit to penetrate the minuter Pores, and to dissolve the Lime. EXPERIMENT V. Quicklime being immersed in Spirit of Wine in a Retort, and the Spirit and Phlegm drawn off, the remaining Quicklime, instead of being slacked, was a more fiery substance than before, for if a piece of it was thrown into Water it would hiss like a Coal, and heat the Liquor; which property it retained several weeks, being kept close from the Air. Whence it appears how much the Texture of Quicklime, and the association of the Spirit of Wine improving that Texture, contribute to the Phaenomena offorded by Quicklime; and that the Spirit of Wine was associated with the Quicklime is probable, since Part of it became a Spiritless Phlegm; and I have observed, Quicklime and Spirit of Wine sometimes to come over in white fumes. To which I shall add, that in such distillations the Odour of the Spirit hath not only been changed, but its taste rendered more fiery, and brisk: But the success is not always the same; being diversified according to difference of the Quicklime, which may be more or less calcined; or the stone may be of a different nature itself. EXPERIMENT VI. But to proceed to other Experiments which show, that Heat may be produced mechanically. A nail hastily hammered grows hot, the Parts of the metal being by that force vehemently and variously determined; tho' the hammer and Anvil be not warm; so that hence it appears, that it is not requisite a calorifick Body should be hot itself, the Hammer being able, tho' cold, to warm the Iron it beats upon; and so the head of a nail grows hot, when it can pierce no deeper into wood, the force of the beating Hammer being not spent in depressing the nail, but putting the resisting Parts into agitation. EXPERIMENT VII. And once I caused a piece of Iron to be beaten by three Smiths, till it grew so hot as to kindle Sulphur upon it. EXPERIMENT VIII. And that Heat may be produced by percussion and attrition appears further, since Iron grows hot by being boiled, a knife by whetting, a Brass nail by being rubbed, and flints by being struck together. EXPERIMENT IX. To show that Heat may be produced without the attrition of contiguous Air, I placed pitch under Water; and by the Sunbeams cast into a Focus by a burning Glass upon it, it was not only melted, but seemed to boil and smoke. EXPERIMENT X. The Powder of slacked Quicklime, washed from its Salts, being mixed with Salarmoniack and melted together, the cold mass being put into a Glass, upon an affusion of Water, grew too hot to be touched with one's hand, tho' the Salarmoniack itself in Water produces Cold. EXPERIMENT XI. Salarmoniack and filings of Steel being sublimed together, the Caput Mortuum in which the greatest Part of the Salt remained, instead of increasing the coldness of Water, being poured upon it several Months after the Caput Mortuum was first laid up; gave the Water a notable degree of Heat. EXPERIMENT XII. Equal Parts of Antimony and Salarmoniack being sublimed with several degrees of Heat in a Glass-Vessel, we obtained three several substances; which being severally powdered; the Caput Mortuum which was like Antimony, being put into Water in which a Thermoscope was immersed, scarce raised the Liquor sensibly: But the yellow sublimate which consisted of the Sulphureous flowers of Antimony and the more Volatile Salts of the Salarmoniack, caused the Weatherglass in another parcel of Water to descend a quarter of an Inch, and the lower sublimate which was black, being put into a third parcel of Water the Liquor in the Weatherglass subsided near three Inches. But the like Experiments being tried with the Caput Mortuum of Minium and Salarmoniack, it neither caused the Liquor in the Weatherglass to rise or fall; but the sublimate raised from these ingredients, caused the Liquor to subside a little. EXPERIMENT XIII. Whether Solvents dissolve Minerals, and cause that Heat observable in their Action, by any Antipathy betwixt the Mineral and the Menstruum, or whether it did not rather proceed from the violent agitation of the parts of the Metal, either dissolved by the insinuation of its parts into the Pores of the Metal, or by obstructing the passage of some aethereal Matter through those Pores, which wanting its usual course dissolves the Metal, by forcing a new way, I shall not undertake to determine; but having agitated Oil of Vitriol with four times its weight of Water, thereby it obtained a sensible Heat; from which Experiment it appears, that the Heat produced by Minerals depends not on a conflict of Acid and Alkalies, since Water is void of either of those chemical qualities. EXPERIMENT XIV. If a piece of wet Ice be thrown into a Viol, which before contained Oil of Vitriol, the Oil mixing with the Water dissolves the Ice, and causes a strong Fermentation, and a violent Heat. EXPERIMENT XV. Half an ounce of Spirit of Wine being mixed with an ounce of Oil of Vitriol, acquired a considerable degree of Heat presently, and almost most filled the Bottle with Fumes; and the Bottle grew so hot at the last that I could not hold it in my Hand. The like Succeeded, only in a more remiss Degree, with common Brandy; and also with Aqua Vitae. EXPERIMENT XVI. Tho' the Chemists teach, that the Incalescence of Bodies depends on an Antipathy of the mixed Bodies, yet I found an intense Heat ensue the Mixture of Parts of the same Bodies; viz. Calcined Colcothar, and Oil of Vitriol. EXPERIMENT XVII. Oil of Vitriol and Oil of Turpentine mixed together, produce a considerable degree of Heat. EXPERIMENT XVIII. An ounce of rectified Petroleum being mixed with an equal weight of Oil of Vitriol, the former Liquor seemed to work upon the surface of this, like a Menstruum upon Metal; the Fumes of the Oil of Vitriol rising into the Ol. Petrae; and the mutual re-action of both the Liquors caused a moderate Warmness. And we had almost the like success with Petroleum, and Spirit of Nitre. But in these last mentioned Trials, Spirit of Salt made use of instead of Oil of Vitriol had no such considerable Effects. EXPERIMENT XIX. Oil of Vitriol caused a considerable Effervescence upon Filings of Steel; especially if they be soaked in Water: And it will grow sensibly hot with Lime, Oyster-shells, Chalk, Lapis Calaminaris, etc. EXPERIMENT XX. Oil of Vitriol grows hot with Cherries, and likewise with Raisins of the Sun beat in a Mortar, as well as with several other Vegetable Substances, and very considerably with Crumbs of white Bread. EXPERIMENT XXI. Oil of Vitriol causes a considerable Heat if mixed with minced Flesh. EXPERIMENT XXII. Tho' Sea-Salt imparts a Coldness to Water, yet with Oil of Vitriol it causes Heat; yet with Sal Armon. part of which consists of common Salt, it produces a Coldness. EXPERIMENT XXIII. Common Sulphur acquired a Heat by attritition, and emitted sulphureous Steams copiously; so that Sulphur itself, as well as other Bodies, owes its Heat to local Motion. EXPERIMENT XXIV. Equal parts of Sal Armon. and Quicklime being fluxed together, an ounce of the Powder put into Water, caused a violent Heat, tho' Sal Armon. itself produces Cold. EXPERIMENT XXV. We observed that beaten Sublimate being mixed with powdered Antimony, after it had stood some time in the Air, the Mixture grew sensibly hot, which Phaenomenon I attribute in part to the Moisture imbibed from the Air, since it is requisite to make the Experiment succeed, that it should be exposed in a moist Cellar. EXPERIMENT XXVI. Trials have assured me, that in Summer, fine Sulphur and Filings of Steel being mixed together in Water, will grow intensely hot, if stirred about an hour after they are mixed; and will likewise emit Steams copiously. EXPERIMENT XXVII. Several Trials have convinced me, that a Mercury may be so prepared as to afford an Incalescence with Gold. EXPERIMENT XXVIII. Having distilled from Quicksilver four times its weight of Oil of Vitriol, and by that means reduced it to a Powder, which upon the account of the Salts of the Menstruum was white and glistering, and being put into Water in which a Weatherglass was immersed, it caused the Spirit to rise manifestly; which is the more remarkable, because Helmont observes, that the Salt adhering to the Mercury, corroded in a good quantity, by Oil of Vitriol, if it be washed off and coagulated, becomes a kind of Alum. And this Phaenomenon is still the more remarkable, because Vitriolum Martis made with Oil of Vitriol and Filings of Steel, being put into Spirit of Wine, was not impelled up as by the former Mixture, but after a while rather subsided. Common Sublimate dissolved in Water, neither sensibly depressed or raised the Spirit of Wine. CHAP. XIII. Of Mercury growing hot with Gold, communicated in the Transactions of Feb. 21. 1675/ 6. Of Mercury growing ho with Gold. HAving obtained a Mercury fine and clean, and even purged by Sublimations and Distillations, and incorporated a multitude of heterogeneous Particles with it, so that they could not be discovered, and much less separated, except by a skilful Artist; I mixed sometimes half and sometimes an equal quantity of Calx of Gold with this Mercury, in the Palm of my Hand, stirring and pressing it with the Finger of my other Hand, by which means the Ingredients being mixed, they grew sensibly hot in a Minute; and I observed, that when they were mixed in equal quantities, they would produce a much greater degree of Heat, than if their Proportion was not exact. And the like success ensued, when the Mixture was preserved from being contiguous to the Skin, by being contained in a piece of Paper, laid betwixt my Hand and it; and the same succeeded in the Hands of other Persons. But with Silver, it would not produce an Incalescence. But tho' this Mercury grows hot with Gold, yet I much question, whether, as Chemists call them, Mercurii Corporum, made by extraction from Minerals and Metals, will grow hot with Gold, as I found Antimonial Mercury did. And I am far from affirming, that that which is called Philosophic Mercury, or even those obtained from Gold and Silver are fit for such uses, than common Mercury skilfully purged and impregnated with the subtle and active Particles of congruous Metals and Minerals. To what hath been said of this Mercury, I shall add, that it preserves its quality of growing hot with Gold two or three Years, and tho' it be distilled from Gold again and again. And whereas its usual to take eight or ten parts of Quicksilver to make an Amalgama with Gold; this Mercury would do it, being used in an equal Proportion. As for the manner of preparing this Mercury, I don't think it convenient to publish it, only this I shall say, that it may be made more ways than one, and without employing. Antimony, or such solid Metals as Mars. But that of ours, I observed, succeeded best, in the production of Heat, by being mixed with Quercetanus' Calx of Gold, viz. by melting Gold with three or four parts of Silver; for by putting this into Aq. fortis the Silver will be dissolved, and the Gold remain in the form of a Calx. But lest an Incalescence, produced by such a Calx, should be supposed to proceed from saline Particles of the Aq. fortis working on the Quicksilver, I shall add, that it will not produce such an effect on common Quicksilver; but ours will cause an Incalescence even with pure Leaf-Gold. CHAP. XIV. New Experiments to make Fire and Flame ponderable. EXPERIMENT I. A Thin Plate of Copper being placed in a Crucible, which had a Hole on purpose in the bottom of it, this Crucible was inverted into another, which contained flaming Sulphur, so that the Copperplate was exposed to the Flame of it. In two Hours the Sulphur being consumed, the Copperplate was manifestly swelled; and tho' its Weight at the first was but a Dram and a half and twenty five Grains, yet it became thirty two Grains heavier, which is about a fifth part above its former Weight. EXPERIMENT II. Refined Silver being placed over the Flame of Sulphur after the same manner as the Copper was, in an Hour and a half weighed one Dram five Grains and three quarters; its weight before being a Dram wanting two Grains. Whether it depends on the closeness of the Metal, and incongruity of the Pores, that Silver acquires not proportionably so great a weight as Copper, I shall leave to the Reader to consider: But from these Experiments it appears, that the Corpuscles of Fire, like other Menstruums, may be united with the Bodies it works upon. EXPERIMENT III and IV. An ounce of Copper Plates, being kept in a shallow crucible in a Cuppelling Furnace two hours, weighted thirty grains more than before. But an ounce of filings, in three hours' time, were caked into a lump, and weighed forty nine grains more than before. EXPERIMENT V. Calcined Hartshorn, and an ounce of Brick; being two hours in a cupelling Furnace, the latter neither increased or lost of its weight, but being exposed to the Air in a scale, by imbibeing the moisture of the Air, in a little time caused it to preponderate; but the Hartshorn lost near eight grains of its former weight; which I supposed to be caused by an Evaporation of some moist Particles of the Air, because by being exposed to the Air a while, it increased in weight again. EXPERIMENT VI and VII. An ounce of Tin being calcined in a Cupel under a Mouffler, in two hours had gained a dram in weight. And an ounce of Lead placed upon a Cupel made of calcined Hartshorn was turned into a lethargy upon it, and the Part of the Cupel was lost in the fire, yet the Lead and it weighed seven grains more than before. EXPERIMENT VIII. A Cupel made of ten Parts of Bone-ashes, and one of Charcoal-ashes, with a sufficient quantity of Ale, weighed about two ounces, and this being placed under a Mouffler, and weighed again when it was throughly hot, it weighed two grains more, but being kept under the Mouffler two hours longer, and then weighed whilst red hot, it had gained twenty one grains in weight, and by being exposed a while to the open Air, it grew three grains heavier than before. EXPERIMENT IX, X and XI. Four drams of filing of Steel, in two hours increased in weight one dram, six grains and a quarter. A piece of silver, which before weighed three drams thirty two grains and a quarter, in an hour and a half increased to 34 1/● grains. Another time half an ounce of filings of silver in three hours gained six grains. A drachm of Zink or Spelter in three hours gained six grains. EXPERIMENT XII. Two drams of filings of Tutenâg, a metal brought from the East-Indies, being kept upon the Cupel two hours, was not melted into lumps, but looked like Cerus and Minium powdered and mixed together, some Parts appearing white and others red, the Calx being weighed had gained 28 ¼ grains. EXPERIMENT XIII. To try whether in Cupellations, all the Lead that is usually employed about them, flies away in smoke, we heated a Cupel and weighing it, placed two ounces of Lead and a drachm of filings of Copper upon it, and after it had been two hours in a Cupelling Furnace, tho' nothing appeared upon the Cupel, worth weighing distinctly, yet weighing the whole together, they amounted to four ounces three drams and eleven grains, which wanted but nine grains of the whole weight of the Cupel and metals, so that allowing for what the Cupel itself might have gained, the greatest Part seemed to be sunk into the Cupel. EXPERIMENT XIV, XV and XXI. To show whether metals separated from an immediate contact with the fire would have their weight increased by it, we included an ounce of filings of Steel in two Crucibles luted together, and in two hours being taken out, they had acquired a dark colour, betwixt black and blue, and were increased in weight five grains, and this Experiment being repeated they gained six grains. Two ounces of Copper in an hour and half gained eight grains, the like quantity of Tin being partly reduced to a white Calx, and partly melted in a yellow lump like Gold, it had gained six grains in weight. But an ounce and four drachms of this Copper being a second time exposed for two hours to a strong fire in two Crucibles as before, gained ten grains more in weight, and had divers dark coloured flakes upon the Metal, which upon handling, for the most part, fell off. Adrachm of Tin being mixed with two ounces of Lead, tho' at the first the mass was dry at the top, and seemed swelled and discoloured, yet Tin gives Led such an Indisposition to Cupellation, that it answered not our Expectation. EXPERIMENT XVI, XVII and XVIII. Copper being made use of which consisted of thinner Plates than the former, an ounce increased twenty one grains in weight. Half a pound of Block-Tin being kept in Fusion in a Glass-Retort placed two days in a sand Furnace, it increased about two grains in weight. I tried likewise to make a Precipitate of Mercury per se in sealed Glasses, but either by their breaking or other Inconveniences, it answered not my design. EXPERIMENT XIX and XX. A Calx of Tin per se which weighed an ounce, being kept upon a Cupel under a Mouffler two hours, gained in weight one drachm and thirty five grains, and became much whiter than before. No Part of the Put was melted, much less reduced into Metal. An ounce of filings of Steel, which had been before exposed to the fire increased in weight two drams and twenty two grains; the filings being baked together, and when broke appearing like Iron. CHAP. XV. Additional Experiments about arresting and weighing of igneous Corpuscles. EXPERIMENT I and II. EIGHT ounces of Block-Tin being cut in pieces and put into a good round Vial, with a long neck, and being cautiously melted over Quick-Coals, the Glass being frequently shaken, to promote Calcination, near an hour, the neck of the Vial being most of the time preserved from the steams of the Coals with a cover of Paper; the Tin which was partly calcined, increased eighteen grains in weight. This being done we melted the remaining metal into thin Plates, by which Operation, it lost three grains of the eighteen it had got; but being a second time exposed to Calcination in another Vial, it afforded a much greater Quantity of it than before, and increased in weight to eight ounces and twenty four grains. In which Trials it is observable, that agitation much contributes to the Calcination of Metals. EXPERIMENT III, IV, V. Eight ounces of Tin being exposed to calcine in a Bolt-head Hermetically sealed, the Glass flew in pieces, and a yellowish Liquor, which was of an odious taste and smell, was found in the neck. But the Experiment being a second time repeated, the Metal being suffered to cool, before the Glass broke, the weight was twenty three grains more than before, tho' the whole Calx amounted to no more than four scruples and eight grains: The top of the Metal was very asperous and of a dark colour, tho' the neighbouring Surface and some places near the dark coloured Calx, which was between the bottom and lowest part of the lump, was of a Golden colour by candlelight. Two ounces of filings of Tin being exposed to Calcination two hours in a small Retort, at the first several steams issued out at the small Apex of the Stem, but then the Apex being sealed up, a yellowish clammy substance thinly spread and which smelled like fetid Oil of Tartar, was gathered in the neck; and the Glass being broke, the lump of Metal which was in some measure covered with a grey Calx, weighed twelve grains more than before. EXPERIMENT VI and VII. An ounce of filing of Zinke being kept in a Bolt-head four hours over live Coals; fumes copiously were emitted out of the unstoped Apex of the Stem; and the whole remaining Zinke, and the flowers which had ascended being weighed, wanted five grains of an ounce. But four ounces of Lead being enclosed in another Retort, it was held over a fire two hours; and then the Apex which was small being sealed up, the Glass was exposed to the fire two hours longer; in which time the Surface of the melted metal was dark and rugged, and Part of it was turned into a dark coloured Calx. The Lead being weighed had gained about thirteen grains in weight. EXPERIMENT VIII and IX. Pieces of red Coral being exposed to the fire, till of a dark colour, gained three grains and a half in weight. Fresh and strong Quicklime being placed upon a Cupel two hours, and which before weighed two drams, increased in weight twenty nine grains. From whence it appears, that tho' Lime hath been before exposed to the fire, yet it is capable of having more igneous Corpuscles united with its substance; from whence we may infer, that tho' Limestone by calcination hath lost much of its weight, yet it may have received a considerable addition from the fire, which may in Part make amends for those Corpuscles which have flown away; upon which account it may be uncertain in other Bodies, which we have made Trials with, how much weight they have truly received from the fire, since it is uncerain how much of their first weight might be lost in Exhalations. CHAP. XVI. A discovery of the Perviousness of Glass to ponderable Parts of Flame. EXPERIMENT I. TO show that Glass is Pervious to the ponderable Part of Flame, I shall to the Experiments already laid down subjoin. That having fixed a small Pan which contained Sulphur, upon another which contained Coals, to continue its Flame; I contrived it so that nothing but the Flame of the Sulphur should come at the Retort, and that the fire and smoke of the Coals should be carried off another way, which being done, two ounces of filings of Tin were Hermetically sealed up in a Retort, and the Glass being gradually exposed three hours and a half to the Flame of the Sulphur, there was a good quantity of grey Calx at the bottom, and upon some Part of the Metal. In which Operation, it gained four grains and a half. And the Experiment being again repeated, the Metal acquired eleven grains and a half. And that it may not be thought that the increase of weight depended upon Particles of Glass dissolved and fixed upon the Calces, I shall add, that I several times exposed Glasses to the fire without perceiving any considerable alteration in the weight of the Glass. EXPERIMENT II. Tho' common Sulphur be a Body homogeneous enough, consisting of inflammable Parts, and an acid near akin to Spirit of Vitriol; yet to vary the Trial, I made use of inflammable Spirit of Wine, over the Flame of which, a Glass Retort with an ounce of Tin was held for two Hours; the Calx being considerable in quantity, was weighed, together with the remaining part of the Tin, which was hardened into a Lump, and it appeared that it had increased its weight four grains and a half. EXPERIMENT III. An ounce of Lead being sealed up in a Retort, and exposed to the Flame of Spirit of Wine, seven scruples were turned into a grayish Calx, which being weighed again with the rest of the Metal, it appeared, the increase of Weight was six grains. NB. But lest it should be thought, that the Particles of the Flame, which increased the weight of the Metal, were turned into Metal, I weighed the Calces in Air and Water, and found, that whereas Lead is to its Bulk of Water as 11 ½ to 1, this Calx was but as 9 to 1. From which Experiments it appears, that Metal receives an increase of Weight from Flame, and that too, through the Pores of Glass. But tho' I believe that Glass is penetrable to the Parts of Flame, yet I am far from thinking that it is pervious either to Chemical Liquors, Quicksilver, or Air. And this I shall add, that it may be worth while to consider, whether all the parts of Fire are fine enough to penetrate Glass, since Metals acquire not so much weight when shut up in Glasses, as when exposed to the open Fire. And it may be likewise considered, whether the Pores of Glass are naturally large enough to give way to the Fire's igneous Particles, or whether their Heat and rapid Motion does not enlarge the Pores of the Glass, and contribute to their Penetration of it: For I know a Menstruum, which will not work upon a Metal whilst cold; but when hot it will reduce it to a Powder. And on this occasion I shall add, that till I am further satisfied, I shall forbear to determine, whether the Rectitude of the Pores of Glass contributes to the Perviousness of it, and whether metalline Vessels are pervious to the ponderable parts of Flame, or not. Having laid down these doubts, I shall thence deduce the following Corollaries. COROLLARY I. Confirming the Parodox, That Flame may act as a Menstruum, and make Coalitions with the Bodies it works upon. From the Experiments laid down it appears, that Flame is capable of acting as a Menstruum, not only in dissolving, but by associating with the Parts of the Body it works upon, and thereby to add Substance and Weight to them; and tho' it renders not Lead and Tin liquid, yet it may still be accounted a Menstruum, it not being a constant property of a Menstruum to dissolve the Body into a liquid; since Tin dissolved in Aqua fortis remains in the bottom in the form of a white Calx. And when Oil of Vitriol is drawn from Quicksilver, it leaves the Mercury in the form of a white Powder, but a small Part of which, will be dissoluble in Water. And one thing observable in this Menstruum is, that whereas other Menstruums are several times the proportion of the Body dissolved, in this, the Corrosive makes but a twentieth part of the Body corroded. COROLLARY II. Proposing a Paradox about Calcination and Calces. From our Experiments it appears, that Bodies may be calcined, without having the greatest part of their Substance driven away, and only the Caput Mortuum, and some fixed Salts; remaining behind, as the generality of Chemists and Philosophers teach; since it is evident, that in our Trial, no considerable Particles flew away, but that the Metal gains more than it loses. And hence we may have reason to judge of the erroneous opinion of those who suppose Saccharum Saturni to be the sweet Salt extracted by the Spirit, whereas it appears, that it plentifully concurs in the Composition of it; so that from hence it appears, that the Calx of a Metal, may be in some cases not the Caput Mortuum or Terra damnata, but the Magistery of it, since the bulk of the Body is preserved, and it only, with a Solvent acquires a new form. And I have elsewhere made it appear, that the dry Calx of Lead may be turned into a malleable Metal again, without Flux-powder, or any other Additament. COROLLARY III. From the foregoing Trials it likewise appears what will become of the Epicurean and Cartesian Doctrines of Fire; the one teaching, that tho' Fire may penetrate Glass, yet it passes through Metals, without being arrested by them; and the other, that igneous Particles cannot penetrate Glass. Whether Fire is arrested in Meat as it roasts or not, I shall not undertake to determine; but if it does, it may be considerable in reference to men's Health, to employ Fire which may be least noxious. COROLLARY IU. From hence it likewise appears, that so subtle, spirituous, and fugitive a Body as Fire, may by uniting with congruous Parts of Matter, form a ponderous and stable Body; and whether the Sunbeams may have the like effect on several Bodies it works upon, I shall leave to be considered. And I shall also leave others to consider, whether all the Particles of Fire and Flame, that are subtle and agitated enough to penetrate Glass, and fasten themselves to included Bodies, be reduced by Ignition to the same Form, or else retain somewhat of their proper Qualities, only I shall add, that in such kind of Inquiries it may be of use to compare the specific gravities of the Calces of Metals, made in Glasses, by the operation of Flames, whose Fuels are of very different Natures. CHAP. XVII. New Experiments touching the relation betwixt Flame and Air. BEfore I lay down the Experiments, I shall first proceed to offer the Difficulties which occurred in the Trials; and first, that some of them in which the Burning-Glass was employed, I could only try them in clear Sunshining Days, the concentred Rays of the Sun being otherwise inconveniently reflected and partly refracted. Secondly, Where I was forced to employ hot Irons, if the Cavity of the Receiver was large, the Iron would be cold before the Air was exhausted; but if it was small, the Cement would be melted; so that I was forced to make use of a peculiar sort of Cement, which was not so subject to be melted. But to these difficulties I shall add, that we must not be too apt to conclude, that the Receiver in these cases is exhausted sufficiently, when the Mercury in the Gage is depressed; since that may happen upon the account of the Air expanded by the Heat of the Iron; and therefore the Air is to be exhausted, till the Mercury in the Gage can be depressed no lower. But if it should be asked, whether a Vacuum may not more conveniently and speedily be made by Mercury, in the Torrecellian Experiment? I shall answer, That tho' the Vacuum be more nimbly made, yet the Phaenomena exhibited there are apt to be influenced by some extricated Particles of Air expanding themselves, it being impossible to leave that space wholly void of Air; besides it appears by a Bubble being broke in my Engine, that it exhausts the Air more clearly than Mercury; since in a Vacuum made by the latter, the Air included in a Bubble was never able to expand itself powerfully enough to break it. Besides, there is one conveniency in our Engine, that, as Air extricates itself, it may be drawn out by plying the Engine as occasion requires, whereas in the Torrecellian Experiment, the Vacuum is made all at once; besides the Mercurial Tube is not so proper for the following Experiments as our Engine is. But to proceed to the Experiments contained under the following Titles. The I. TITLE. Of the difficulty of producing Flame without Air. EXPERIMENT I. An endeavour to kindle Sulphur in Vacuo Boyliano. A Piece of red hot Iron, half an Inch in Diameter, and an Inch thick, being conveyed in a glazed melting-Pot into our Receiver, we carefully exhausted the Air, and letting down flowers of Sulphur in a Paper, the Paper was presently consumed, and the Sulphur falling into the Concave Surface of the Iron, only smoked a little, but did not actually kindle. EXPERIMENT II. Another way we made use of to kindle Sulphur in Vacuo was, by putting Flowers of Sulphur into a Glass-Bubble, and when the Air was exhausted, placing it upon live Coals, the Heat would not kindle the Sulphur, but raise it in the form of a yellow Varnish up to the opposite side of the Glass, and by turning that to the Fire, it would rise again to that side of the Glass which was uppermost. EXPERIMENT III and IV. To show how much interest the Air hath in the production of Flame, when the Sulphur was too cool to burn without Air, we took off the Receiver, upon which it presently flamed: And another time when the Receiver was thrice successively so far exhausted, that the Sulphur ceased to Flame, each time, that the Air was again let in, we could discern several flashes of fire, which by their blue colour appeared to be Sulphureous flames. EXPERIMENT V and VI Endeavours to explode Gunpowder in Vacuo. The Beams of the Sun in the Summer being cast upon Gunpowder in Vacuo, it first smoked and then melted, but did not explode whilst I continued the use of the burning Glass. But another time having conveyed the Iron mentioned before red hot into our Receiver, as soon as it was exhausted we let down a piece of Paper with Gunpowder in it, and tho' the Paper was consumed, and the Sulphur melted, yet it did not go off. But the Experiment being repeated with a grain of very good Sulphur, when it had burnt so long that we no longer expected an Explosion, I let in the Air, and sometime after it went off. EXPERIMENT VII and VIII. Several grains of Gunpowder being conveyed into an exhausted bubble, and that placed upon the live Coals, it flamed considerably and afforded sublimate, which by the light of a candle exhibited livid colours of a Rainbow. In our Physicomechanical Experiments, we mentioned an Experiment where a Pistol was fired in our Receiver; but the Receiver not being then sufficiently exhausted we reiterated the Experiment, and found, that when by the help of the Turn-Key, the Trigger of a primed Pistol was pulled by a string purposely fastened to the Trigger and Turn-Key, the Powder in the Pan would not go off, yet when a little Air was let in, the Gunpowder remaining in the Pan, would flash off when the lock was cocked, and let off as before; yet one thing observable was, that tho' the Gunpowder would not explode, when the Receiver was totally exhausted, yet the violent percussion of the flint would cause sparks of fire to fly from it. EXPERIMENT IX. Aurum Fulminans was exploded in the exhausted Receiver with a considerable noise, by the Sunbeams cast upon it with a burning Glass; and a quarter of a grain being let down by the Turn-Key upon a piece of Iron red hot, it exploded with a flash, which was visible; the place where the Experiment was tried being purposely dark; and a yellowish powder was scattered about the Cavity of the Receiver. The II. TITLE. Of the difficulty of preserving Flame without Air. EXPERIMENT I. Of the flaming of Sulphur in Vacuo. FLowers of Sulphur being kindled upon a metalline Plate and conveyed into the Receiver, when the Air began to be sucked out gradually decayed, till at the last, the Receiver being totally exhausted, the Flame was extinguished, and upon a reingress of Air, it only began to smoke again. EXPERIMENT II. A larger piece of Iron than that formerly mentioned, being made use of, and conveyed into a Receiver, a good quantity of Sulphur was let down upon it, which flamed considerably, and continued not only till the Receiver was exhausted, but a little after, and till it seemed to be extinguished for want of fuel. In trying of which Experiments, the following particulars are to be observed. First, that the Iron is placed on a Pedastal of Tobacco-pipe-clay not too near the Glass lest it should break it. Secondly, upon the concave Surface of the Iron, we placed a Convex-shell which was shaped like a flattish bottom, to keep the Ha●…e from having too large a Surface, and consequently from consuming too fast. Thirdly, it will be convenient, for the more commodious discerning of the Phaenomena of this Experiment to try it in a dark place. And fourthly, it is convenient to advertise that the Sulphur frequently so obscures the Glass with its fumes, which partly stick to it, that sometimes it is very difficult to discern what happens within the Glass. Fifthly, it is requisite the Heat of the Iron should be considerable, that the Flame of the Sulphur may be more lasting; the flaming of it depending on the Heat of the Iron, and not the force of its own Flame. EXPERIMENT III. A very volatile and saline piercing Liquor being dropped upon filings of Steel, the Mixture grew hot, and emitted out of the Vial it was contained in, very fetid steams, which would kindle at the flame of a Candle, and continue to burn a good while; where we conveyed it into our Receiver, and upon the first Exsuction of Air it flamed brisker than before; and likewise upon the second and third; but after it went out, it would not be kindled again, tho' the Air was let in upon it. EXPERIMENT IU. Spirit of Wine being impregnated with a Mineral, which tinged its Flame, I conveyed it into the Receiver in a small Glass-Lamp with a slender wick; and observed, that in half a minute after the Pump was plied, the Flame was extinguished: But letting Air in and out as occasion required, I observed, that when the Flame began to decay, the Turn-Key being successively drawn almost out, the Flame lasted a minute and a half, and sometimes longer. The Turn-Key being taken out in the beginning, it lasted two minutes or better. A Pipe being bedded in the Cement at the bottom of the Glass, and having at each end an open Orifice, almost of the bigness of that which the Turn-Key usually fills, the Flame burned very well, and would have continued longer than it did if we would have permitted it. The Orifice at the top being stopped, the lower was left open, yet the Flame began to decay, but Air being blown in with a pair of Bellows, it was presently refreshed again, yet in a minute after it was quite extinguished. EXPERIMENT V. Flame preserved under Water. Tho' it is taught that Naptha and Camphire will burn under Water, yet I could never find that they would; but three ounces of Gunpowder, a drachm of well Charcoal, good Sulphur half a drachm, of choice Salt-Petre near a drachm and a half, being all powdered and mixed together, a Quill or a Tobacco-pipe stopped at one end being filled with this Mixture and kindled in the Air, would burn, till it was wholly consumed, under Water, the force of the Flame keeping the Water from breaking in upon it at the open end. In which Experiment Flame seems to be continued without. Air, there being no Air to preserve it under Water, but what may be lodged in the Pores of the Water; except some moist Particles betwixt the Particles of the Nitre, in favour of the necessity of Air to preserve Flame, may be supposed to be rarified and form Air for a time, as the rarified exhalations which flow out of an Aeolipile, which are not true and permanent Air, but presently return to Water again. EXPERIMENT VI. Of the flaming of a Metal in Vacuo. Having placed the piece of Iron, so often made use of in our Receiver, we designed to let a parcel of Sulphur fall upon it, but when we went to drop the Sulphur down, by accident it fell on one side the Iron; and whilst we were considering what to do, we discerned a a blue Flame in the middle of the Glass, which continued much longer than that of ordinary Sulphur, and when we opened the Receiver, we found that it was afforded by a metalline substance which lay melted in the middle of the concave superficies of the Iron, being a composition of Lead and Tin; but tho' these Metals mixed, so opened the Bodies of each other as to yield a Sulphureous fuel for Flame in Vacuo, yet in the open Air they would not. The III. TITLE. Of the difficult Propagation of actual Flame in Vacuo Boyliano. EXPERIMENT I. HAving kindled some Sulphur, which was of a peculiar sort, upon the Iron so often mentioned, I let down a piece of Spunk upon it, when the Receiver was exhausted; and by being contiguous to the flames it was turned into a substance as black and brittle as Tinder, and disposed to kindle when touched with fire. EXPERIMENT II. Another parcel of the same Sulphur being kindled in Vacuo Boyliano, Camphire, tho' in the open Air, disposed to draw the Flame of Sulphur, yet it was not kindled by hanging in the Flame of it. And a Match being partly dipped in Sulphur, and let down upon the hot Iron, burnt as far as the Sulphur reached, but no further. EXPERIMENT III and IV. Having placed a piece of Paper upon the Plate of our Pump and whelmed over it a very clear and thin Receiver, we laid a train of Gunpowder upon the Paper, and observed, that tho' by a good Burning-Glass, several grains would be exploded; yet those would not kindle those that were contiguous to them, the Propagation of Flame so much depends on the free access of Air. And to confirm this, I shall add, that a little Instrument made to try Gunpowder, being charged and primed and suspended in Vacuo, tho' by the help of a Burning-Glass the priming would be exploded, yet that would not kindle the Powder contained in the Box; but when the exhausted Air was let in again, and the Pan new primed, tho' the Receiver was shut, it would in that close Air go off readily; and also in the open Air. EXPERIMENT V. Gunpowder being put into two Bubbles, one of which was exhausted and the other not, they were placed upon Live-coals, upon which, when they had stood a while, they where both burst in pieces, but without the appearance of any Flame, which effect seemed to depend on this, viz. That the Heat of the coals acted not only on a few grains of Powder at once, but upon the whole Area, so that every Particle being equally acted on, as to sense, they were exploded at the same time, so the Focus of a Burning-Glass acting uniformly on Aurum Fulminans, causes it to explode at once, but it may be so ordered, that the Focus not sufficiently warming one Part, a partial explosion will only ensue. CHAP. XVIII. New Experiments about the relation betwixt Air and the Flamma Vitalis of Animals. EXPERIMENT I. Animals included in Receivers with Flame and Air. REctified Spirit of Wine contained in a Glass-Lamp with a thin Wick, and at the same time, a small Green-Finch, being both conveyed into a Receiver eighteen Inches high, and which was large enough to contain about twenty pints of Water, the Flame of the Lamp was extinguished at the end of two Minutes; but the Bird being brisk at the end of the third Minute, was taken out. And when the Bird recovered again, the Experiment being repeated, the Flame was extinguished in two Minutes, but the Bird continued well longer. The Experiment being again repeated with two Lamps, they were both extinguished in a Minute, but the Bird continued well five or six times as long. A Mouse continued well a long time after the Lamp was extinguished. And the same Mouse being shut up in another Receiver with a Wax-Candle, seemed to have received no damage ten Minutes after the Candle was out, tho' the Air was clouded with the Smoke of it. EXPERIMENT II. A Goldfinch and a Piece of a Candle being included in a Receiver, large enough to hold two Galons, the Candle was extinguished in two Minutes; but the Bird in that smoky Air continued well a good while after. And the like succeeded with a wax Taper in another Receiver. Being shut up with a piece of a Candle in another Receiver, which the Air was drawn out of, the Bird outlived the Flame, but not without Convulsions. And the like succeeded with a wax Taper. The same Bird being included with a piece of Charcoal two Inches long, and half an Inch thick, when the Air was so far pumped out, that the Coal was past being renewed by letting in the Air, the Bird was sick, but presently recovered. And the same Experiment was repeared with the like success. Whether the Fire and Flamma vitalis of Animals feed upon distinct parts of the Air or not, and whether the former destroys its Pabulum sooner or not, I shall leave to be considered. EXPERIMENT III, IV, and V. Of the shining of Glow Worms. It being the opinion of some, that the shining of Glow-worm's proceeds from a kind of Effulsion of the Biolychnium, or Vital Flame; I shall subjoin, That Glow-Worms being included in a Receiver in the Dark, as the Air was exhausted, their Light was diminished, and as it was let in again, renewed. And lest this should depend on the Glow-Worm drawing the luminous Part of its Body into the dark Part, and so obscuring it, I enclosed the luminous Parts by themselves, and observed the same Phaenomena as before; save that, upon the Re-ingress of Air, they seemed more lucid than before. The like Experiments being repeated with a dead Worm, it at the first retained its Light when the Air was exhausted, but after a while it diminished and increased as the Light of a live one, only it shone more vividly, and as the Light of the live one was a greenish blue, so this afforded a white yellow. EXPERIMENT VI. A Mouse being weighed alive, and then strangled, tho' nothing fell from him, he seemed 7/16 of a grain lighter when dead. And a young Catlin of about ten or eleven Ounces weight, lost four grains of its weight whilst a strangling, so many subtle parts being evaporated by its violent Struggle. So that the common Tradition that Animals are heavier when dead than alive holds not true. To this Experiment, I shall add, that having enclosed Silkworms Eggs, and those small Infects which turn to winged Infects, and form Gnats, in Vacuo, neither of them hatched or generated as in the open Air. CHAP. XIX. New Experiments about Explosions. THE Learned Dr. Willis, and others having endeavoured to account for some Phaenomena by Explosions, I shall lay down the following instances of Explosions made by Liquors. EXPERIMENT I. Strong Spirit of Nitre being put into a Bolt-head, to the quantity of an Ounce, upon the Affusion of Spirit of Wine, part of it flew up to the Ceiling of the House, and dropping down upon a Man's Skin burned him terribly; and as Spirit of Wine was successively poured in, it grew intensely hot, and emitted red Fumes, which would take Fire at a Candle held a quarter of a Yard from the Mouth of the Glass, and would burn there till blown out. And an ounce of Spirit of Nitre being conveyed into another Bolt-head, and a Bladder tied over the top of it, which contained Alkohol of Wine, a little of it being poured into the Bolt-head, it caused a vehement Explosion, by which the Bladder was presently expanded, and the Fumes presently made their way out in the form of an Orange-coloured Smoke. EXPERIMENT TWO and III. Oil of Vitriol and Oil of Turpentine being shaken together, produce a strong Ferment, and an Expansion or Explosion. The Blood of Fishes and Sea-Monsters is actually cold, and yet they move very violently; wherefore in favour of those that believe Animal Explosions, I shall add, that if Oil of Vitriol and Salarmoniack be mixed gradually, the one being contained in a Bladder, and the other in a Bolt-head, to which it is tied (as in the first Experiment) when the Salarmoniack falls upon the Oil, it will cause a violent Explosion. CHAP. XX. New Experiments concerning the relation betwixt Light and Air, in shining-Wood, and Fishes. Communicated in the Transactions of Jan. 6. 1667/ 8. EXPERIMENT I. Of the relation betwixt Light and Air. A Piece of good shining Rotten-wood, being conveyed into our Pneumatick Engine, at the seventh Suction it began to grow more dim, and at the tenth it quite lost its Light. EXPERIMENT II. But as soon as the Air was let in again, the Light appeared again like a little Flash of Lightning, and more vivid than before. These Experiments being a second time tried, the Light was diminished at the second Exsuction, and at the sixth disappeared, which was but six Minutes from the first Exsuction. EXPERIMENT III. In a third Trial, the Wood having been kept in Vacuo half an Hour, recovered its Luminousness upon a readmission of the Air. EXPERIMENT IU. A shining Body being included in a Receiver, and the Air exhausted till the Body had almost lost its Luminousness, we left it some time in that rarified Air, and observed that the Light gradually diminished, tho' the Receiver was no further exhausted. EXPERIMENT V. Having included shining-Wood in such an Instrument as Mr. Hook hath invented to compress Air, I found, that tho' the Air was forcibly compressed, the Light was not sensibly impaired. EXPERIMENT VI. Shining-Wood being included in a sealed Glass, for two Days retained its genuine Lustre, but the third Day the Light was more obscure. EXPERIMENT VII. What effects the exhausted Receiver would have had on Bolonian Stone, Diamonds and Glow-Worms, I had not opportunities to try: But a piece of red hot Iron being stuck in Tobacco-pipe-Clay, and conveyed into the Receiver, there was no sensible effect produced by evacuating or replenishing the Receiver. EXPERIMENT VIII. Wood being enclosed in a Glass hermetically sealed, and that conveyed into the Receiver, the Rays of Light were equally visible through the vacuous Medium, as through the Air when let in again. EXPERIMENT IX. We took a Glass Tube sealed at one end, and putting a piece of shining-Wood into it, we propped it with a Cork, to keep it from falling out; which being done, we inverted the open end of the Tube into stagnant Mercury, and conveying it into a Receiver, we exhausted the Air, that that in the Pipe by expanding itself, might make its way out, through the Quicksilver; which being done, we observed, that the Wood which lost its Light in the rarified Air, recovered it again, when by the Pressure of the external Air the Mercury was buoyed up within two Inches of the Wood, the rarified Air being thereby condensed again. EXPERIMENT X. A shining Fish which was very vivid, lost much of its Lustre, when the Air was drawn out; and a small piece of it, which was less luminous lost its Light in another Receiver, but recovered it again, when the Air was let in again. EXPERIMENT XI. To try whether the Fish which retained its Light in some measure, did it upon the account of some peculiarity in its Nature, I enclosed a large piece of Wood in a Receiver, but it lost its Light in Vacuo, and regained it when the Air was let in again. EXPERIMENT XII. Rotten shining Fishes being included in Vacuo twenty four hours, they regained their Light again when the Air was let in. EXPERIMENT XIII. Considering how much Putrefaction contributes to the shining of Fishes, and the Air to Putrefaction, I took a Fish, and hanging a piece in the Air a little before the time they usually grow luminous, I included another in Vacuo, to try whether the Fish would grow luminous there, or whether, tho' it appeared not to be so, yet when the Air was let in it would disclose its Light; but the Attempt being twice made, the one was frustrated by the breaking of the Glass; and the other, by the peculiar Qualities of a Fish, which in the Air grew not luminous in the usual time, nor much beyond it. EXPERIMENT XIV. A shining Fish being immersed in Water in a wide mouthed Glass, was not at all affected, upon the exhausting of the Receiver, or when the Air was let in again. EXPERIMENT XV. A shining Fish, which lost not its Lustre upon the exhausting of the Receiver, was kept in Vacuo forty eight Hours, in which time it lost its Light wholly, till the Air was readmitted, and then it shone again; but the Receiver being a second time exhausted, it lost its Light in four Hours, but renewed it again upon a re-access of Air. The suddenness of this renewed Light, put me in mind of those Lights which are sometimes seen in Vaults and Caves newly opened, and upon the first ingress of Air; but those are not so lasting, by reason of the less tenacity of the substance which yields those luminous Rays. Another Fish being included in Vacuo three days, renewed its Light when the Air was let in; but a third did not recover its luminous quality till it had remained sometime in the Air. And two other shining Fishes, being included three Days in Vacuo, when the Air was let in again, that which was first most vivid, recovered its Light first; and the other sometime after. CHAP. XXI. Observations and Trials about the resemblances and Differences between a burning Coal and shining Wood Communicated in the Transactions of Feb. 1667/8 Resemblances. Resemblances of a shining Coal and Wood 1. BOTH of them afford Light. 2. Both of them require the presence of the Air to continue their Light. 3. Being deprived of Light by withdrawing the Air, they recover it again upon the re-access of it. 4. Both of them will lose their Light in Water. 5. Coldness of the Air extinguishes not their Light; for, shining Wood being put into a Glass Tube sealed at one end, and that placed in a frigorifick Mixture, till Water contained in another Pipe was froze, it still continued Light, tho' a shining Fish lost its Light in a quarter of an hour. Differences. Their Differences. 1. A live Coal would be extinguished by Compression, but shining Wood will not. 2. Shining Wood will recover its Light when the Air is let in again, but a Coal will not. 3. Shining wood will contive to give light in a close Glass, but the Coal will not. 4. A Coal emits smoke, but the other does not. 5. A Coal consumes, but the other does not. 6. A Coal is hot, but shining wood is not warm, which I discovered by applying to the shining wood the Ball of a Weatherglass described in the History of Cold, in whose Stem is contained a Pendulous drop. CHAP. XXII. Some Observations about shining Flesh, communicated in the Transactions of December 16. 1672. A Flesh which shines in the dark. A Neck of Veal which was observed one Night to be Luminous in the Larder, afforded the following Phaenomena in a dark Room. 1. It shone in several places; those shining spots varying likewise in bigness and form. 2. The Parts which shone most were those grisly or bony places which the Butcher's cleaver had past. And we perceived likewise that the Medulla Spinalis did shine. One place of a Tendon shone, and several spots in the flesh distant from the Bone. 3. By the light afforded by these spots, I could discern several Letters in the Title of the Philosophical Transactions; the most vivid Rays being of a greenish blue, like the tails of Glow-worm's. Neither a Weatherglass or the touch could discover any more Heat in those Parts than in others; nor were they in the least putrid. 4. The window of the Larder is Northward; and the floor a story below the Kitchen, and separated from it only by a Boarded floor. 5. The Wind was high, and South-west, the Air being hot for the season. The Moon was past its last quarter, and the Mercury in the Barometer stood at 29 1/16 Inches. 6. A piece of a shining bone being cut off the thickness of half a Crown shone on both sides, and the place it was cut off shone likewise but more faintly. 7. The Flesh lost some of its light by rubbing; but imparted no light to my hand: But the Flesh being pressed betwixt two pieces of Flesh it lost nothing of its Light. 8. A piece of it, having lain a quarter of an hour in inflammable Spirit of Wine lost its Luminousness; but in Water it continued an hour without being impaired. But being conveyed into our Pneumatick Engine, it was diminished gradually and considerably. 9 I observed several Luminous places in a Leg of Veal brought out of the same Larder. 10. A piece of Veal kept all Night in a Phial, shone in the Morning, and continued its Light till the sixth Day at Night. 11. A Pullet hung up in the same Larder, appeared also to be Luminous. CHAP. XXIII. Observations of a Diamond that shines in the dark. Observations on Diamonds. HAving met with a Diamond, which, tho' it would not yield light in the day, would afford a conspicuous light in the Night, I thought it would be of no small use in explaining the abstruse Nature of Light. And tho' a great many think it no rarity, that there are Carbuncles and Diamonds which shine in the dark, yet there are some who deny, that there are any shining stones at all, as Boetius de Boot; Johannes de Laet, and Olaus Wormius, yet Vatemannus and Garcias ab Horto, pretend to be Eye witnesses of Carbuncles which shone in the dark; and Marcus Paulus Venetus tells us, that the King of Zeilan had a Ruby as thick as a Man's arm, and a Palm long. And two Russian Cossacks tell us, that they heard from the People of Cottay, that their King had a Ruby which would shine Night and Day. And Benvonuto Cellini, an Italian Writer, gives us an account of a Carbuncle which afforded a considerable Light in the Night. And we ourselves have been informed of a shining substance found in Scotland. And I am further told, that a Dutch Admiral had a Diamond, which when he opened a Coffer under Deck in a dark Room, would shine by its native Light, which is the more strange, because that is a much colder Climate than the East-Indies; for it is observable, that warmth much contributes to the shining of such stones, since rubbing will cause some to shine, which when cold will not; which makes me the less doubt of what is said of right Turquois, viz. That it changes colour as the wearer is sick or well, and loses its splendour after Death, which is attested by the Observations of Boetius de Boot, and Olaus Wormius; and tho' Antonio N●ri tells us, that a Turquois discoloured and grown white, will regain its colour, if immersed in Oil of sweet Almonds, yet Wormius tells us, that a Nephritick stone being dipped in a Decoction of herbs lost its virtue. And it is observed, that the Texture of Oculus Mundi will be so changed by being left in Water, that from Opacous it will become Transparent, which acquired lustre it will soon lose in the Air. Observations made on Mr. Clayton's Diamond. It was a flat Table Diamond ⅓ of an Inch long, and less in breadth, of a bad Water, and less vivid in the day than other Diamonds, being blemished with a whitish Cloud about the middle of it, which blemish covered near a third part of the stone. This Diamond being looked upon in a shady place in the day, and also with a Microscope, neither any thing peculiar in the stone, nor any light was perceived. Secondly, when the Candle was removed in a dark Room, it did not shine without being rubbed or otherwise prepared. Thirdly, I could neither produce Light by rubbing together two Pebbles, nor by a vehement attrition of Rock-Crystal, nor by two Diamonds, as by this stone. Fourthly, it was hard enough to grave upon Rock-Chrystal with it, and was endued with an Electricity. Fifthly, by rubbing it in the dark, it would be excited to shine like rotten wood, but much fainter than the scales or slabber of a Whiting, or than Glow-worm's; and it presently ceased after the attrition was ended. But being rubbed brisksly it would continue its Light much longer, so that it lasted eight times as long as it was a rubbing▪ Sixthly, holding it near a faint fire excited its Luciferous Qualities a little, but by holding it near a Candle it was more apparently excited in a dark Room; and it acquired a little glimmering by being held near a red piece of Iron, as also by being contiguous to my naked Body sometime. Seventhly, by being rubbed till it acquired Luciferous Qualities, it was also Electrical, but not when it was excited to shine by the Heat of the Fire or a Candle. Eighthly, attrition varied its Luciferous Qualities, as the Cloth varied in colour; but on white and red it succeeded best. It was likewise excited in some measure by being rubbed upon a white wooden Box; and a purely glazed Earth, which excited it much better than any other Body except white ones. Ninthly, when it was excited, being plunged into Water, Spirit of Wine, Oils of all sorts, Acid Spirits, and Alkalizate Solutions, none of them destroyed its shining properties, but when it was taken out of the Water it was not so easily excited as before. Tenthly, neither Spittle nor warm Liquors would extinguish its Light; but being rubbed with a transparent horn, I could discover Light through it, and sometimes little sparks of fire. Eleventhly, being rubbed upon a blue Glass, the faint Light was not visible through it, but being first excited and then applied to the Glass, the Rays were tinged in their passage through it. Twelfthly, by pressing it hard upon a piece of white Tile it became Luminous, as also it discovered a short Coruscation when I pressed my finger upon it: And if I thrust or stuck the point of a Bodkin against it, it would discover a short, but not a lasting Coruscation, so that its Light seemed to be promoted by pressure rather than attrition. The same Experiments being tried with other precious Stones, some Diamonds would by attrition be brought to a glimmering Light, but others would not; but neither the other precious Stones, nor Artificial or Natural Crystal would afford the least glimmering of Light. CHAP. XXIV. The Aerial Noctiluca, or some new Phaenomena; and a process of a Factitious self-shining substance. Of an Aerial Noctiluca. Phosphorus' are either natural, as Glow-worm's, some sorts of rotten Wood and Fishes; or artificial, which are the chief subject of this discourse; and are either, First, such as will retain a Lucidness sometime after they have been exposed to the Sunbeams, as the Bolonian Stone, and Phosphorus Hermeticus of Balduinus, which may be made of Chalk, the latter of which succeeds much better than the former; for it is presently excited in the Sunbeams, and even at the flame of a Candle, and continues to shine a considerable time in the dark; yet this advantage the Bolonian Stone hath above the other, that it retains its Virtue of being excited much longer. Or, Secondly, self-shining substances, such as are usually called Noctiluca; and are either consistent or liquid, such as Mr. Crafft brought to London, the consistent one being of a gummy Nature and constantly lucid; but the other apt to vanish, if exposed to the open Air. To which I shall add, one of my own preparation, which does not shine itself, but when exposed to the Air, the Effluvia mixing with it became lucid, which therefore I call the Aerial Noctiluca: In preparing of which, from some Parts of a Man's Body, it was not only difficult to hit upon the true degree of Heat, but the Vessels in which it was raised by Distillation, being not able to hold out so long as they should, we were forced to save the Luciferous matter, by small parcels and in distinct Vials. Observations made on the Liquor which was contained in the second Vial, which tho' it was large enough to contain two ounces, had but a spoonful of the Liquor in it. 1. By Daylight this shining Liquor was not near Diaphanous, but of a muddy grayish colour. And when it was disposed to shine in the dark, the Cavity of the Vial above the Liquor seemed to be full of whitish fumes, tho' at other times transparent. 2. The Vial when close stopped was not Luminous in the dark, but the Light or Flame appeared as soon as it was exposed to the Air, and the Vial was unstopped; and that the Accension and Propagation of this Flame depended on the contact of the Air, appeared, since agitation would not kindle it, but when the Bottle was unstopped the kindled Flame would gradually be propagated downwards; and if a few Bubbles of Air were only let in by removing the cork aside and putting it close in again, the Flame would appear upon the top of the fumes, without being able to propagate itself much downwards. To which Observations I shall add, that when the Flame appeared it was most vivid the nearer the Air, and when it was extinguished, it first disappeared in the bottom, and then expired at the top. But when the Vial had been unstopped for some time, when it was stopped again, the Air that had leisurely insinuated itself would cherish the Flame for an hour or two. 3. It was observable, that when the Air had been long penned up with this shining Liquor, the spring of it would be so far weakened, that when the Vial was unstopped, the external Air would presently rush in again, from whence appears the Interest of the Air, in promoting the shining of this Acry Noctiluca. Of the Reason of Noctiluca's As for the Reason why the Air should▪ contribute to such Phaenomena, I shall offer the following Conjectures, viz. That the Saline Parts of the Air, caused a Fermentation in the fumes of the Liquor, by which means, they being briskly agitated, are either conveyed to, or unite with the common, Aether, and affect the Eye jointly; and tho' Mr. Craft's consistent Noctiluca shines when closed up from the Air, yet that may be attributed partly to the Viscousness of the Luciferous matter, which is less apt to be dissipated; which I am the apt to believe, since it being once exposed to the open Air, it was considerably wasted and was rendered much more violent; so that it produced considerable effects of actual Heat. But tho' I am inclined to believe that the Air contributes thus to the shining of these Noctiluca's, by putting the Particles of the fumes into a brisk agitation, yet whether it acts immediately on the fumid matter it invades, or whether it dissipates it, or acts after the manner of a Vital Spirit, or further, whether the Air uniting with these fumes forms a Body fit to be agitated about, by the Aether, I shall leave to be further inquired into. But to return to our Observations. 4. Tho' agitation before the Vial was unstopped would not kindle the Light; yet when it was opened, it would be increased by it. And even when it was in its dark state, if I poured a little of it upon my hand, and rubbed it with my finger, it would presently become vivid, and emit store of Luminous Rays, as well as fumes very offensive to the Nostrils; and when I ceased to rub, and the Luminous Quality was lost, it would be renewed again by a repeated attrition; but in a little time its lucid Virtue would decay. 5. As for the degree of the Light of this Luminous matter, it was equal with that of some rotten wood; and it was observable, that the Rays of it were reflected but weakly by black Bodies, but appeared very lucid when enclosed in white ones, tho' I could not perceive the Rays of it reflected from a reddish Diamond or an Emerald. This Light in respect of itself was Opacous, but transparent when held near external Light, and interposed betwixt it and the Eye. 6. I tried whether the Sunbeams would excite those fumes, which are Concomitants of its Luminousness, but could not perceive them raised in the least. As for the Nature of this Liquor I could not perceive it upon my Tongue either Acid or Alkalizate, but Empyreumatical, almost like that of Spirit of crude Tartar, its smell being like that of an Empyreumatical Oil, compounded with a stink like that of stolen Urine. It turned not Syrup of Violets green, as volatile Alkalies, or urinous Salts do; nor did it by other Trials appear to be an Acid. 7. This Liquor in its lucid State being agitated, several consistent Particles being by that Agitation raised, and sticking to the sides of the Glass, appeared to be more lucid than the Fumes. Having wet my Finger with this Liquor, and rubbed it upon my Hand till it became luminous, I immersed my Finger in Water, upon which the Light was extinguished; but when I took it out of the Water, and rubbed it again, it became lucid as before. 8. But twice I observed, that there was such a peculiar Temper in the Air, that it continued to flame twelve or fifteen Hours after it had been stopped up. And at last this Liquor became so effaete, that it would not yield Light, till its Parts were agitated by Attrition, or put into motion by the Heat of the Fire. 9 To what Observations have been already made, I shall add the following, made on the Liquor contained in the first Vial. Observations on the Liquor contained in the first Vial. 1. The Liquor being muddy shone ten hours after it was first poured into the Vial, and when the Vial was unstopped the Fumes were put into a circular Motion round the sides of the Glass, like a Whirlwind; which perhaps might depend in some measure on the violent Ingress of Air, upon opening the Vial; tho' I have sometimes observed lucid Rotations of Matter in the Cavity of the Vial, a considerable time after such Eruptions. 2. The Flames which were afforded by rubbing these Liquors, yielded white Fumes of a rank offensive Smell; the Colour of the Flame being yellow, and tremulous in their Motion, and inconstant, sometimes flashing out more than at other times; but it neither burned the Skin, nor singed fine Linen: So that if any, it must resemble that Flamma Vitalis which is supposed to reside in Animals. 3. A Pencil being dipped in this Liquor, and drawn upon white Paper, deposed only its watery part; but the more gummy Matter in the Pencil being squeezed out, it seemed to burn like a Candle, and sometimes shooting downwards, as if it were played about the Hairs that made up that part of the Pencil, which brought into my Mind those Verses of Virgil, Ecce levis summo de virtice visus juli Fundere lumen Apex, tactuque innoxia molli Lambere flamma Comas, etc. Aeneid. And it was observable, that this Flame would successively appear and disappear for a considerable time, and sometimes when the wreathing of the Hairs was violent, the Flame would be accompanied with a momentary, tho' sensible Heat, yet it would not fire Gunpowder; tho' some of the consistent Matter, whilst it was preparing, being taken out with a Knife, and the Knife rubbed betwixt the Thumb and Fingers with a blue Calico Apron, the Matter received such an Impression from that Attrition, as put its parts into so violent a Motion, that two Holes were burnt in the Apron. Some of the Liquor contained in the Receiver, and diluted with Water, turned Syrup of Violets green, and fermented with Acids. 4. Some of this Liquor being contained in a Vial, and conveyed into our Pneumatick Engine, tho' the Air could not be so far exhausted, but that there was a sufficient quantity left behind to kindle the Flame; yet the Commotion occasioned by Pumping, would be, as if it were ventilated, or blown up, and made to shine more vividly. And a piece of Paper moistened with this Liquor, being conveyed into a Receiver, tho' by the Commotion of the Receiver, the Flame seemed to be still increased, yet in those Parts betwixt the Folds it appeared to be much less than in the open Air; and tho' when moist Air was let in again the Flame was extinguished, yet upon a removal of the Receiver, when the Paper was exposed to the open Air it renewed its Flame. 5. Some of this Liquor being at the first filtered, the Substance remaining in the Filtre being enclosed with it in a wide-mouthed Glass, it became luminous when exposed to the Air. And another piece of Paper being shut up in another Glass, when it was spread open in a dark Place, several Flashes sprang out incessantly and successively, first in one place then in another, and were not only various in their Figures, but had frequent Emications and Tremble. 6. Some of this luciferous Matter being dissolved in an aqueous Liquor, which was transparent when it was settled, tho' a moderate Agitation would not produce Light in it, yet being set in a Sand-heat in a Bolt-head till the Ball was too hot to be touched with one's hand, I caused it to be removed into a dark place, and found that it had acquired a manifest Luminousness, and the Liquor being variously agitated and broke, several Flakes of Light ascended to the top of the Stem; and when the Liquor was agitated till it was spread over the inside of the Ball and part of the Stem, it was adorned with luciferous parts of Matter, which twinkled like so many Stars, and descended in Lines, some of which were very obliqne and pleasant. 7. Once I observed, that when the Liquor contained in a Bolt-Glass was not very hot, having given it a rude shake, a Spark risen on one side, and spread all over the Cavity of the Ball. And to what hath been observed, I shall add, that some of this Liquor was having been hermetically sealed up, it retained its luciferous Qualities a long time. 8. The way to make the Phosphorus Balduini, is the following, viz. Having dissolved fine white Chalk in Spirit of Nitre, or clean Aqua fortis, it must be filtered through Cap-paper, and the clear Solution is to be evaporated till there remains a dry substance; which being spread over the inside of a round Vessel which will endure the Fire, you are to give it a peculiar degree of Heat; and which commonly requires a convenient shaped Vessel, whereby the Flame or Heat may be reverberated, till the Matter hath acquired a disposition to retain Light; and then the Vessel must be covered with a Glass or fine Crystal Cover, to keep it from the outward Air. 10. The Process which we took to make our Airy Noctiluca was the following; We took a considerable quantity of putrified Urine; which was distilled till all the spirituous Parts were drawn off; after which the superfluous moisture was also abstracted, till the remaining Substance was brought to the Consistence of a thick Syrup, which being well incorporated, with three times its Weight of white Sand, the Mixture was put into a strong Retort, to which a large Receiver was joined in a good measure filled with Water: Then the two Vessels being carefully luted together, and a naked Fire being gradually administered for five or six Hours, that the Phlegmatic or Volatile Parts might come over first. When this was done, the Fire was increased, and at the length for five or six Hours, made as strong and intense as the Furnace was capable of giving; by which means good store of white Fumes came over, almost like those that appear in the Distillation of Oil of Vitriol, which when they are passed, and the Receiver grew clear, they were after a while succeeded by another sort, which seemed, in the Receiver, to give a faint blueish Light, almost like that of little burning Matches, dipped in Sulphur. And last of all, the Fire being very vehement, a more ponderous Substance passed over, which fell to the bottom of the Water, which being taken out, appeared to be luciferous. But whether the shining Faculty depends on the volatile and spirituous Parts of this Animal Liquor, or of the fixed Salt, and ponderous Oil, I shall not determine, till further satisfied by Observations. An Appendix to the Aeerial Noctiluca. 1. Some luciferous Matter, that had a long time lost its shining Faculty, being heated by the Fire, presently shone vividly enough, and continued to do so whilst it was sufficiently warm; but in a few Weeks, it likewise lost this Disposition of Heating. And tho' some consistent Matter had lost its Power of shining, yet the Superficies being taken off, the Matter that lay under it rubbed upon my Hand would presently become luminous. 2. Tho' this luminous Matter be not feculent, yet it usually leaves some of its gummy Parts sticking to the sides of the Vial, which may be discovered by heating the Vial, or if it be broke in pieces, and agitated in another Vessel; for by that means, the Parts being rubbed one against another, and variously placed with their sides upwards and downwards, they would every way diffuse a clear Light. 3. A twelfth part of a Vial being filled with a liquid Phosphorus of another kind, so that a greater quantity of Air might be contained in it, it continued to shine without unstopping the Vial. And I sometimes observed several Exhalations like Clouds, or Aggregates of Smoak, to roll to and fro in the Cavity of the Vessel; and would grow much more lucid upon shaking the Vial. 4. When it had lost its Light for some time, it filled the Cavity of the Vial, when unstopped, with Fumes, which like those of the other Noctiluca's, appeared white in the Light, and luminous in the Dark. A Bolt-head half full of this luminous Matter being sealed up hermetically, it continued luminous six Days and Nights; and when a great part of the Liquor was poured off, the remaining Sediment being spread about the sides of the Glass, by inverting it, they appeared like so many bright twinkling Stars in a clear Night. CHAP. XXV. New Phenomena exhibited by an Icy Noctiluca, or a solid self-shining Substance; and first, some Qualities of the Noctiluca itself. Some Qualities of the Noctiluca. HAving by a method, not unlike that taken to produce the Aerial Noctiluca, obtained the following Qualities in it; and, first, It came over in Distillation in little Grains of different Shapes and Sizes, and most commonly irregular, being void of Colour, and when held against the Light, transparent; and the greater Pieces looked so like Ice, that for that reason I called it the Icy Noctiluca. But tho' generally it was colourless and transparent, yet some small Pieces were Opake, and of various Colours compared with each other. 2. This Noctiluca is heavier in Specie than Water; and tho' consistent, yet not so hard as common Ice; but it is brittle, and may be spread upon a solid Body, like the unmelted Tallow of a Candle, it may be melted in hot Liquors without waste, but in the Air a great Part of it will be consumed. As to sense it is Cold; but is of such a Texture that it easily becomes hot upon agitation. 3. When held in the Air it yields a vivid Light if wet over, and when first exposed to the Air, it not only shines, but emits store of Effluvia, as long as it is kept there; when it is immersed in Water it ceases to shine and also to smoak, but as soon as it is taken out, it gins afresh, and if part be immersed and part above Water, the latter will shine vividly tho' the other will not. The Qualities of Water in which it had been immersed. 4. The Water in which this Noctiluca had been sometime immersed, had a strong and penetrant taste like a Mixture of Brine and Spirit of Salt, and relished a little of Vitriol. Being held in a small Concave Vessel of Silver over lighted Coals and ashes, it evaporated very slowly, and would not shoot into Crystals, nor afford a dry Salt; but coagulated into a substance like a Jelly, or the whites of Eggs, which would be easily melted by Heat. When kept on a hot fire it would first boil, and then make a crackling Noise, and the Explosions would be accompanied with flashes of fire and light, which if they were small were generally blue, like flames of Sulphur, but more vivid, and sometimes bluer; but the greater flakes appeared yellow and very Luminous, and these Phaenomena appeared likewise for some time after the Vessel was taken off. When this matter was almost melted by Heat, if it was permitted to cool, it acquired a rosinous Consistence, and tinged the Flame of a Candle blue. By the Fire working upon it, it acquired a Garlic Smell, and being left in the Air all Night, it turned to a Liquor almost as strong as Spirit of Salt. Being put upon the Fire again, it would afford the same Phaenomena as before, but some of the Matter which before broke out in Flashes, sometimes risen only in the form of Smoke, of a rank Smell. And tho' the quantity of this Matter was small, yet it afforded Flashes plentifully for an Hour. What Liquors it would be dissolved in, and what not. It would not dissolve in cold Water, tho' the Water would be thereby impregnated; so Crocus Metallorum impregnates Wine or Water, without having its Bulk diminished. It fermented not with Spirit of Sal-Armon. nor did it lose its luminous Virtue, but would shine when exposed to the Air again. Oil of Vitriol when cold would not dissolve it, but when hot would melt it; and it would lie at the bottom of so heavy a Liquor. Aqu. fortis had not visible effect on it, nor Oil of Turpentine when cold; but the latter being hot, it wholly vanished in a Night's time, without making any alteration in the Oil. Being put into Oil of Cloves, and melted by a Fire, when it was cool, and the Vial unstopped, it yielded not only a Light, that was rendered more acceptable to the Standers-by, by its grateful Smell; and the like succeeded with Oil of Cloves, in which Liquor, when impregnated with the Noctiluca, it was observable, that the Vial being opened in a dark place, it would yield a flash of Flame very vivid, which would last a Minute; and sometimes, if a Candle were in the Room, the shining fluid would appear of a pleasant blueish Colour; and another thing observable was, that the Light would vanish, whilst store of white Fumes remained upon the Liquor, as if the Light chief depended on the finest and purest Part. In Oil of Mace it did not appear luminous, nor in Oil of Aniseeds. This Noctiluca continued in Spirit of Wine, a considerable time undiminished. 6. This Noctiluca being included in rectified Spirit of Wine, was partly dissolved; and left some earthly Parts at the bottom of the Liquor, but did not discolour it: upon unstopping the Vial no Light appeared, but being dropped into cold Water, the Drops were kindled by it; but those Flashes immediately disappeared, the Water not being luminous; which Phaenomenon, lest it should be thought to be an effect of Antiperistasis, I dropped the impregnated Spirit upon hot Water, and found, that the same Phaenomenon succeeded. And this Noctiluca diffuses its Virtue so far, that one Grain impregnated a thousand of Spirit of Wine. As for the reason why these Flashes so suddenly disappeared, it might proceed from a sudden dispersion of the Particles of the Spirit through the Water, and the Avolition of the luciferous Matter. So Camphire dissolved in Spirit of Wine, and dropped upon cold Water, is left upon the Surface of it, the Spirit being immediately dispersed through the Liquor. Experiments discovering a strange subtlety of Parts in the Glacial Noctiluca. Having dissolved a Grain of our Noctiluca in a Drachm of Spirit of Wine, and added gradually fifty times its weight of Water, the Noctiluca rendered the whole light, when shaken in the Dark, so that one Grain rendered 100000 times its weight of Liquor luminous; and what was more strange, was, that not only the Steams appeared luminous, but the Light seemed in some measure diffused through the whole Water, which I am apt to believe proceeded from the Exhalations which shined through that Diaphanous Water, tho' when the Glass was shaken the whole Mass appeared luminous. And the Experiment being further prosecuted, a Grain of the Noctiluca dissolved in Alkohol of Wine, and shaken in Water, it rendered 400000 times its weight luminous throughout. And at another Trial I found, that it impregnated 500000 times its weight; which was more than one part of Cochineel could communicate its Colour to, the utmost being 125000 parts of Water. In which Experiments, ⅛ of the Noctiluca was undissolved. And had we to the aforementioned Estimate, added the Proportion of the illuminated ambient Air, the Expansion of this Noctiluca would have been incomparably greater than the abovementioned number denotes. But to demonstrate further the strange Subtlety of our Noctilucal Matter, I shall add, that three Grains of our Noctiluca being placed upon a flat-bottomed Glass, that was broader at the Top than the bottom, and shallow, that the Matter might be more fully exposed to the Air, it was placed in a shelving Posture, that upon its resolution in the moist Air, it might presently run down, and not hinder the free Evaporation of the remaining Matter: The Vessel being thus placed, all the Fragments about ten a Clock at Night began to shine briskly, and continued to do so till reduced to very small Parts; so that so small a parcel of our Noctiluca continued to shine above a hundred and fifty Hours. In which time the following Circumstances were observable, First, That the luciferous Fumes were visible both Night and Day; and risen from the Particles of the Noctiluca, like Smoke from so many Chimneys. Secondly, This Smoke was so copious and tenacious, that it lost not that Form till it risen a Foot above the Matter that afforded it; the Motion of it being swift, and sometimes tending directly upwards, sometimes horizontally, and sometimes downwards, as if their Motion had been determined by the situation of the Noctilucal Fragments, by which they were emitted. And one thing further observable was, that when it had been a long time exposed to the Air it emitted strong and odorous Exhalations, distinct from the visible Fumes. As for the Liquor which dropped from this Noctiluca, and which remained in the Glass Vessel, I put it into a Concave Silver Vessel, and held it over Small-Coals and Ashes, where it evaporated not so easily as I expected, but turned into an unctuous Substance, of a dark reddish Colour; and being thence removed and held over quick Coals, it boiled and crackled like Bay-Salt cast into the Fire, and emitted several successive Flashes. Another piece of this Noctiluca, which weighed three Grains, being put into a small Glass Funnel, whose Stem was so fine that it was less than a small Pin's head, and the Pipe of the Funnel being purposely placed in a Vial, to catch the colliquated Liquor; and this being set in a South-Window all Day, and placed in my Chamber at Night, I observed, that it continued luminous no less than 360 Hours. From whence appeared the extraordinary Minuteness of the parts of our Noctiluca; and what is more strange, the Weight of ●●r Noctilucous Matter colliquated, exceeded the Weight of the Noctiluca itself two thirds. This Noctiluca being spread upon Paper, and held to the Flame of a Candle, when the Flame came to the Noctiluca, it burned away in a flashing and spluttering manner, and cracked like Salt. And some of this Paper being put upon Embers covered with Ashes, the Noctiluca would take Fire, and communicate its Flame to the Paper. And to show its inflamability further, I put a Grain of it into Spirit of Wine, and tho' it discoloured not the Flame of the Spirit, which was partly red and partly blue, yet when the Spirit was consumed, and the Flame was contiguous to the immersed Phosphorus, it took Fire, and emitted a yellow Flame copiously. And a piece of this being set on fire by the Sunbeams concentrated, it burned very vividly and clear; and the expiring Flame left behind it a Caput Mortuum, which form several Circles like those of a Sardonix, whereof the largest was white, another yellow, and the third red, all the three Colours being vivid and pleasant. Some part of the Caput Mortuum being left in the Spoon, was presently resolved per deliquium, into a Liquor as sharp as Spirit of Salt; and other parts having free access to the Air appeared combustible. Another instance of the Inflammability of it, was by rubbing it in a Mortar, for by that means it took Fire, and burned vividly, but was soon extinguished by the Fire. Of the burning of Bodies with the Noctiluca. If our Noctiluca be pressed hard betwixt ones Fingers, or against a Board, it will feel sensibly hot; and will sometimes be violent enough to scorch the Skin: And one thing observable is, that Blisters raised by its Heat, are not only more painful, but harder to be cured than ordinary ones. But tho' some parts of this Noctiluca are disposed to take Flame, yet they are not all equally prone to an Incalescence. To these Observations of our Noctiluca I shall add, that some of it being rubbed betwixt Folds of Paper for some time, they took Fire, and so did it when rubbed with Gunpowder, by which means the Gunpowder was exploded: And once when my Servant carried some of it in his Pocket, the Glass being broke, the Attrition and Heat of his Body set it on Fire, by which means several Holes were burnt in his Breeches. To which I shall subjoin, that six Parts of Sulphur, and one of this being mixed and beaten with the haft of a Knife, the Noctiluca shone through the Paper, and as soon as these Ingredients were exposed to the Flame, they immediately took Fire; and once the Experiment being repeated, the Brimstone did not burn with a slow Flame, but flashed away like Gunpowder. And once my Laborant having prepared some of it, and trying to write upon a dry Board, the force of Attrition kindled the Wood, and afforded not only vividly shining, but burning Letters. To try what was the Nature of this saline Noctilucal Matter, I dropped some of it upon Syrup of Violets, and found that it did not turn it green, but of a fine Carnation Colour, as Acid Spirits usually do. And I likewise found, that it presently destroyed the blue Colour, tho' not the other of the Lignum Nephriticum. I likewise poured some of this Noctilucous Liquor upon Filings of Copper, and exposed them to the Air for two or three Days, I found, that tho' the Filings were dissolved, yet the Colour of the Tincture was not a deep Azure, as if made with a Volatile Urinous Salt, but seemed to partake of green and blue. It likewise fermented with Powder of red Coral, and also with Salt of Tartar. From whence it appears, that the nature of our Salt is not Urinous, but of the Family of Acids. But to proceed, I enclosed a parcel of this Icy Noctiluca in a small Vial, and another, together with the Water it came over with in Distillation, and I observed, that the former lost its Light in four Days, and the other in about a Week. But to try whether a sufficient Degree of Heat would not cause our Noctiluca to take Fire, I enclosed some of it in a Glass-Egg, with Hermes his Seal, and found, that the Ball of the Egg being held near the Fire, the Noctiluca presently took Flame and burned much longer than we expected; and when the Flame was over, we sometimes observed a little Liquor in the Glass, the rest of the Matter, by the Operation of the Fire, acquiring a red Colour. Some of this Noctiluca being put into a Glass Egg, and Water poured upon it, when the Water was heated very hot, and the Noctiluca was melted, we poured the Water off; upon which the Noctiluca remaining in the Glass, immediately being exposed to the Air, took Flame, and part of it running out with the Water, burnt fiercely upon the Surface of it, and with a crackling Noise, the remaining Caput Mortuum appearing red. To which relations I shall add, that the Beams of this Noctiluca, passing through an Orange coloured Glass, appeared of a very pleasant Colour. And on this occasion I shall subjoin, that tho' once I could not obtain any Light from some of this Noctiluca included in a Vial with Oil of Mace, as with Oil of Cinnamon, yet upon further Trials, I found that it succeeded. And to what hath been delivered on this Subject, I shall further add, when the Noctiluca was wholly consumed to a Caput Mortuum, that as soon as it was turned with the other side upwards, it would immediately take Fire afresh. THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. BOOK V PART I. CHAP. I. New Experiments of the Positive or Relative Levity of Bodies under Water. Arguments against the Positive Levity of emerging Bodies. WHEN any Body that is lighter in Specie than Water is immersed in it, and upon the removal of that force which depressed it, it rises again, it is usually attributed to the Positive Levity of that Body; but since the instance of Wood emerging is that which is usually offered as an Argument, to it I shall answer, That Wood being a Body full of Pores (except some which will not swim in Water) and upon that account specifically lighter than Water, the Water by the Pressure of that which is incumbent, getting betwixt the Superficies of the Vessel, and the Body immersed, causes it to rise, the Water which succeeds it in its place making a more powerful Pressure against it, than its Specific Gravity enables it to resist. And that Bodies Specifically lighter than Water will be thus buoyed up by it, will appear from the Hydrostatical Paradoxes hereafter to be laid down. And tho' it be usually urged, that the Bodies imimmersed are too closely contiguous to the bottom of the Vessel for the Water to insinuate themselves betwixt; yet from the following Experiment it will appear, that were the contiguous Surfaces so close, the positive Levity of the Wood would not be able to raise it; for two black Marbles, being so exactly polished as to be as contiguous as possibly they might, we tied a Bladder full of Air to the uppermost, and then causing them both to be immersed in Water, the positive Levity of the Bladder, would not cause the Bladder to rise; but as soon as by a servant the uppermost Marble was gradually slipped half off the Polished Surface of the lowest, the Water which before was not able to insinuate itself betwixt the Surfaces of the contiguous Marbles, and to separate them, presently caused the Bladder to rise with a considerable swiftness and force, above the Surface of the Water: Which Event, that it did not depend on Nature's abhorrency of a Vacuum is evident, since that would have an equal force when the Polished Surfaces were wholly contiguous, the Power of Nature's abhorrency of a Vacuum being held by its Assertors to be unlimited. And that it was not the heaviness of the upper Marble, nor want of lightness in the included, appeared, since when the Surfaces of the polished Marbles were not contiguous, the Bladder was able to lift up a weight of six or seven pound, besides the Marble. And to show, that the Bladder might be raised by the Pressure of the Water, according to the laws of hydrostatics usually buoying up Bodies Specifically lighter than itself, having pressed out the greatest part of the Air contained in a Bladder, I tied a piece of Iron to it, and immersed it in a wide-mouthed Glass, which was so deep that the Bladder was totally immersed, and yet not far below the Surface of the Water, and this being conveyed into our Pneumatick Engine, when by exhausting the Air part of the Pressure was taken off, the Air in the Bladder expanding itself, and takeing up more Room in the Water, and consequently becoming so much more Specifically lighter, and the resistance of the Water which endeavours to buoy it up becoming respectively greater, it was together with the suspended weight, raised to the Surface of the Water, and continued there till the outward Air was let in again; and then the Air being contracted into its former dimensions, it subsided again. In which Experiment the positive Levity of the Air was not varied, but only its relative and respective weight in reference to its proportion of Water. And that Rarefaction altars not the positive Levity of Bodies, may appear from the following Experiment; for having oiled a Bladder, and when the Air was expressed, tied it to the neck of a Vial, I found, that in the exhausted Receiver, tho' the Air in the Vial was so far expanded as to fill the whole capacity of the Bladder, yet the Vial neither rose higher; nor subsideded lower when the Air was drawn out, or let in again. CHAP. II. New Experiments about the Pressure of the Air's Spring on Bodies under Water. The Pressure of the Air's Spring on Bodies under Water. TO show that the Spring and Weight of the Air hath manifest effects on Bodies separated from an immediate contact by the Interposition of Water, I shall subjoin the following Experiments. EXPERIMENT II. We luted the neck of a Vial, which was capable of containing above a point of Water, upon that pipe which conveys Air out of the Receiver into the Pump, which being done, we whelmed over this Receiver our large one, and having poured in a sufficient quantity of Water, we closed it up with the Turn-key, that no Air might get out that way, and then the Air being exhausted out of the Vial, if flew into a great many pieces, the sides of the Glass being not able to resist the Pressure of the Air, that lay upon the Surface of the Water in the large Receiver. EXPERIMENT II. The greatest part of the Air being squeezed out of a Bladder, and the Bladder tied to a weight, which kept it something below the Surface of Water contained in a wide-mouthed Glass; this being conveyed into a Receiver, the Air in the Bladder expanded, as the Air on the Superficies of the Water was extracted. EXPERIMENT III. A Brass Plug being fitted to a Cylinder which was closed with a Plate of the same Metal at one end; we put a Bladder half blown into the Cylinder, and placing the Plug upon it, with a weight of a Conical figure upon that; we poured so much Water into the Receiver in which it was placed, as covered the top of the Conical weight, but left the Ring which was fixed to the top of it, and which was fastened to the Turn-key by the help of a string; and things being thus ordered, when the Air above the water was considerably exhausted, the Spring of the Air in the Cylinder raised the Plugg and Weights a considerable height, tho' the whole weight amounted to twenty eight pounds. EXPERIMENT IU. A Glass Vial being closed with Cement, and immersed in a deep Brass Cylinder of Water, this was conveyed into our Receiver, and when the Air which pressed upon the Water was drawn off, the Vial in the bottom of the Water was violently shattered in pieces by the Spring of the included Air, for want of a sufficient Pressure of the Air incumbent on the Water, to resist the force of that Spring. EXPERIMENT V. To show that the Expansion or Rarefaction of Air increases not the positive Levity of Air, we suspended a Bladder half full of Air, with a Counterpoise, at a balance in our Receiver, and tho' when the Air was exhausted, the Bladder was sufficiently distended; yet it seemed to retain the same weight, whether dilated or contracted. CHAP. III. New Experiments concerning an effect of the varying weight of the Atmosphere upon some Bodies in the Water. Communicated in the Transactions of Feb. 24.1672/3. Of the Effects of the differing weight of the Atmosphere on Bodies under Water. COnsidering that the Pores of most Liquors are plentifully stocked with Airy Particles, and that upon that account the Atmosphere may according to its several degrees of weight have considerable Effects on them, I caused three small Glass-Bubbles with slender Stems to be blown, which were so equally poised in Water by their weight, that a little thing would make them emerge or sink. And I observed, that these being put into Water contained in a wide-mouthed Glass, sometimes they would emerge and sometimes subside, and sometimes emerge again, as the Atmosphere varied in weight or degrees of Heat and Cold. And it was easy to observe, that when the Heat of the Air raised one of these Bubbles, the heat of the Sunbeams would so rarisie the Water included in them, as to cause some of it to get out, upon which the Bubbles emerged, but when those Beams were intercepted, the Water being condensed, and getting into the Bubble again, it would subside. But when their subsiding depended on the weight of the Atmosphere, if the Mercury in the Baroscope stood high, the Heat of the Sun would not raise the Bubbles. N. B. 1. That the Bubbles not being all equally poised, sometimes one and sometimes two would rise, as the Air was heavier or lighter, and consequently capable of affecting the lightest only, or all. 2. The Success did not always answer, for when the subsiding depended on some occult cause, they would continue there, as if some airy Parts had insinuated themselves into the Water. 3. The fittest time for these Experiments, and in which they best succeed, is in the Spring, the Air being more subject to vary in its Weight, as well as other things. CHAP. IU. New Experiments about the differing Pressure of heavy Solids and Fluids. Of the different Pressure of Solids and Fluids. ONE great reason why some Learned Men believe that the Air hath no such a considerable Pressure on subjacent Bodies as we teach, is, because they think it would be too heavy for Animal Bodies to live or move under it; but since we have positive proof of it, we may as well doubt whether the Loadstone be endued with an attracting and other Virtues, because we cannot understand how they are performed. Besides, Men being born under such a Pressure, their Bodies seem not only accustomed to it, but proportionably strong. But could we suppose a Man born somewhere, without the incumbent weight of an Atmosphere, doubtless such Bodies would not be so able as ours to resist its Pressure. But it is urged by some, that were there such a Pressure of the Atmosphere, it would cause Pain; but to this it may likewise be answered, that our Bodies being from the Birth accustomed to it, we only feel Pain upon some new unaccustomed and additional Pressure; so when we are accustomed to wear heavy , we are not sensible of their weight, nor are we sensible of the Heat of the Blood in our Heart, because it's habitual to those Parts, whereas if our finger be put into the Heart of a newly dissected Animal, we shall find it sensibly hot. But further, from what I have elsewhere laid down, it appears, that a Cubick Inch of Air will be able to resist the weight of the whole incumbent Atmosphere, and that a little quantity of Air resists a further compression as well as a greater; and I have likewise shown, that the Pores of the Parts of Animals whether fluid or consistent, are plentifully stocked with numerous Aerial Bubbles, which cause those Bodies to swell or expand in our exhausted Receiver. And as for those membranous and fibrous Parts which are not altogether so porous, they are of so strong and firm a Texture, as to resist external Pressure upon that account. Besides, there is a great deal of difference betwixt the partial Pressure of a solid Body, and the Pressure of an Ambient Fluid, which presses uniformly, and is resisted either by the solidity of the Parts, or the Spring of those Airy Particles contained within their Pores. And that the uniformness of the Pressure makes it less sensible, is evident, since it hath been observed, that tho' the Atmosphere is so much lighter upon the tops of some high Mountains, as not to elevate Mercury so high in a Baroscope by three Inches, as at the bottom, yet those that have been upon those Mountains tell us, that they perceived no considerable difference in the Pressure of the Atmosphere above and below; nor are Miners sensible of any great weight upon them, tho' in deep Mines in Mountainous Countries; nor are Divers sensible of any Pressure when under Water; but that Air weighs in Air, and that Water weighs in Water, I have elsewhere made it evident; yet I don't think that a Diver is violently depressed by the weight of the incumbent Water, since from what we have elsewhere delivered it appears, that if a Man's Body were of an equal specific Gravity with the Water, the subjacent Water would sustain him, but his Body being heavier than an equal bulk of Water, the Surplusage of weight depresses it; for which Reason, in some Sea-Water, which is near of the same specific Gravity with their Bodies, Divers find it very difficult to dive. However it is not a little strange, that at so great a depth as one hundred fathom Divers should not perceive a sensible Pressure, especially upon their Thorax and Abdomen: But I am apt to believe that the inadvertency of some of them, rather than any thing else makes them not take notice of it; or else the haste which they rise and sink in; since I have been told by some, that they have perceived a manifest Pressure when they sunk leisurely. And I was likewise told by another, that when he descended a great depth under Water, the Blood was squeezed out of his Nose and Eyes; and another who dived in a Leathern-case told me, that it was so much pressed against his Thorax and Belly, that he was forced suddenly to come up again. But since these Relations are not altogether to be relied on, I shall endeavour to give a Reason why the Pressure is no more sensible; which I take to be the strong Texture of a Human Body, and the uniformity of the Pressure. As to the first, to what I have said of the Resistance made by our Bodies to external Pressure, I shall only add, that a Bladder being tied upon the end of a Cylinder, about an Inch in Diameter, when the Air was exhausted, the incumbent Pressure of the Atmosphere was not able to break it, tho' when a Man's hand was placed there, he was not able to raise it till some of the Air was let in again, the Pressure which held his hand down being equivalent to a Cylinder of Water thirty foot high. But to show the effects of an uniform Pressure of Liquids upon Solids contained in them, I shall subjoin the following Trials. EXPERIMENT I, TWO, and III. Having placed an Egg betwixt two Bladders half blown, in a Brass Cylinder, and cautiously put a Plug upon them, with as much weight upon it as amounted to thirty pound, I placed them all in a Receiver, and when the Air was exhausted, tho' the expanding Bladders must needs press equally against the Egg and the Plug, yet the incumbent weight was raised, and the Egg when taken out as whole as before; the weight it sustained in the Cylinder being not quite so much as the weight of the Atmosphere. But tho' the Egg was able to sustain so much weight when pressed upon uniformly; yet Weights being successively laid upon the same Egg exposed to the open Air, four Pound weight crushed it in pieces. And by further Trials we found, that an Eggshell, which had all the Yelk and White taken out, as also a thin Glass Bubble, being placed betwixt two Bladders, as in the first Experiment, neither of them was in the least cracked. EXPERIMENT IU. To show that what we have taught of the Nature of Fluids', will hold in Water as well as Air, if the Pressure be uniform, we enclosed an Egg in a Bladder almost full of Water, and putting it into the Brass Cylinder, we heaped upon the Plug as many Weights as amounted to seventy five pound, yet the Egg being taken out, was as found as when first put in. In which Instance it cannot be pretended, that the Egg bore no weight, by those that allow not Water to gravitate in Water, since there was a considerable Pressure made by Metalline Weights, which every body allows to weigh in Water. From this Experiment, and the other before mentioned, of an Egg being broke by a partial Pressure, it appears, that the Strength of the Texture of a Humane Body, together with the Uniformity of the Pressure of ambient Water, may be the reasons why Divers feel no greater Inconveniency under Water; for tho' their Thorax may be a little more compressed than other Parts, yet that Part being naturally dilated and contracted, a little Pressure may make no sensible Alteration: But I have been told by a Diver, that at a consicerable Depth, he perceived a painful Pressure upon the Drums of his Ears, till he contrived a way to guard them from that Inconveniency; the reason of which Phaenomenon seemed to be no other, than that in that Part there was not an equal internal Pressure, to resist and counterbalance the external Pressure of the Water. CHAP. V An Invention for estimating the Weight of Water in Water, with ordinary Balances or Weights. Communicated in the Pub. Transact. of Aug. 16. 1669. A Bubble about the bigness of a Pullet's Egg, with a long Stem turned upon at the end, was heated; and, when the Air was most of it expelled, sealed up; and then being by a convenient weight of Lead immersed under Water, it was suspended at the end of a Balance, and counterpoised; and then the Apex of the Stem being broke off with a Forceps, so much Water got into the Cavity of the Bubble, as required four drachms and thirty eight grains to reduce the Balance to an Aequilibrium. Which being done, we drove out the Water by the help of a Flame of a Candle into another Glass, which was counterposed, and we found that it weighed four drachms and thirty grains, which together with what was evaporated and lost, and the weight of the Apex, amounted to the weight first mentioned. So that from hence it appears, that Water weights as much in Water, as it does in the open Air; which according to the best Computation we could make, succeeded a second time in a larger Bubble. As for the Objections which Mr. George Sinclair hath made to this Experiment, since it is the Opinion of our Author, that he only differs from him in Expressions, I shall wave what he there says, as not at all requisite in this Place; and shall only add what our Author hath said, to explain what he means by Water weighing in Water, viz. That it gravitates or weighs, in as much as it tends downwards, upon the account of its specific Weight, tho' it does not preponderate, that is, the Parcel of Water weighed hath but an equal Tendency downwards with the Ambient Water, but upon an additional Weight it preponderates as much as the additional weight increases its Tendency towards the Centre. CHAP. VI Hydrostatical Paradoxes made out by new Experiments. BEfore I proceed to the Hydrostatical Paradoxes, I shall briefly intimate, that tho' I can readily assent to the Hydrostatical Conclusions laid down in Monsieur Paschall's Discourse; yet as for the Experiments he makes use of to prove them by, I must own, I am not satisfied with them; since he makes use of such as require that a Man should sit under Water fifteen or twenty Foot, with the end of a Tube leaning upon his Thigh. But he neither acquaints us how a Man shall be able to continue there, or how he shall discern the alterations in the Mercury or other Bodies, at the bottom. Besides, such Experiments as he proposes require Tubes twenty foot long, and Vessels as many foot deep, which are hard to be got in England; nor is it possible to obtain from a Tradesman, Brass Cylinders or Pluggs, made with so much Mathematical Exactness as he proposes. Having therefore contrived a more easy way to demonstrate the Truths contained in the foregoing Paradoxes; before I proceed to examine them, I shall premise a word or two by way of Postulatum or a Lemma; which consists of three Parts: The first of which is, That if a Pipe open at both ends, and held perpendicular to the Horizon, have the lower of them under Water, there passes an imaginary Plain, which touching the Orifice of the Pipe, is parallel to the Horizon, and likewise, as to sense, to the upper Surface of the Water. To which it will be consonant, secondly, that as long as the Surface of the Water is even, the Water incumbent on this Plain will equally press on all the parts of it. But, thirdly, if there be a greater Pressure on one part of this Plain than another, as when a Stone presses upon it, the Water which lies under that Stone will be displaced, as the Stone subsides successively, till it come to the Bottom. But on the contrary, if there be less Pressure on one part of that Plain than on another, the Liquor will be raised on that part so high, till the Liquor on that part of the Plain gravitates equally as the Water incumbent on the other parts of it; which will appear from the following Experiments. And first, If a Cylindrical Pipe open at both ends, be held in a perpendicular Posture, and the lower end be immersed three Inches in Water, the Liquid within the Tube having a free Communication, will be of an equal height with the external Water, and in thin Tubes, a little higher. But if Oil be gradually poured upon the Water without the Pipe, the superficial Plain will have a greater Pressure upon it without than within, and consequently the Water under the Tube, finding not so great a Pressure within the Pipe as without, it gradually rises, till the external and internal Pressure upon the imaginary Plain be equal. But since this will be further evident from what is contained in the following Paradoxes, I shall proceed to them, as soon as I have laid down the following Experiments, to show Air is not a Body devoid of Weight, as some Peripatetics suppose. The first is, that a Glass Bubble being blown, whose Capacity was short of two cubical Inches, it was instantly hermetically sealed, whilst hot; and when it was cool, being placed in a nice pair of Scales, and then the Apex of the Stem being broke off, the Air rushing in with a noise, caused the Bubble to preponderate half a Grain, tho' by breaking of the Stem under Water, it appeared that the rarified Air remaining in the sealed Glass, possessed one fourth of its Capacity. Another time the same Experiment being tried, the Air contained seemed to weigh near three quarters of a Grain; and the Capacity of the Receiver being filled with common Water, it weighed 905 Grains: So that allowing the Air contained to take up one fourth, and that the weight of the remaining Part was ¼, probably the weight of the whole was about a Grain; and consequently the Water weighed little more than nine hundred times as much as an equal Bulk of Air. PARADOX I. paradox 1 That in Water, and other Fluids, the lower Parts are pressed by the upper. If in a Glass of Water, See Plate 2. Fig. 1. A B C D (see Plate the second, Fig. the first) a Cylindrical Tube be immersed, which contains Oil of Turpentine; and that Oil be suspended there, (by keeping the upper Orifice close, after it hath been sucked up to a convenient height) till the Pipe is depressed to a convenient Depth in the Water; if the lower end of the Pipe B Q be immersed till it reaches to the imaginary Surface G H, and the Oil X Q presses no more upon that imaginary Surface, than the Water without the Tube, than the Oil will be suspended there, and not be able to depress the Surface of the Water below it; but if the Surface of the Oil in the Tube be much above the Water, and it presses more upon the imaginary Surface G H than the Water without, than it will make its way through that Surface, till the Oil within and the Water without are brought to an Aequilibrium again, so that they both equally press upon the Surface G H; and the like will happen, if the Tube be raised to the Surface D S, and gradually on to the Surface L M; for as the Pressure of the external Water grows less and less, as the imaginary Surface is nearer the top of the Glass, so the Oil in the Tube growing preponderant, falls out at the lower end of the Tube, till the Tube T V being almost raised to the Surface L M, but a little Water pressing upon that Surface, the Oil is almost wholly fallen out of the Cylindrical Cavity of it. But if instead of raising the Pipe P Q, it be depressed to the Position N O, the Water incumbent on the Surface E F on the outside the Pipe, being more powerful than the Cylinder or Oil W A, which is only aequiponderant to a Cylinder of Water leaning on the Surface G H, the Oil must be buoyed up by the Pressure of the external Water, and the Space O A filled with Water, so that the Oil betwixt W A, and A O, being both aequiponderant to a Cylinder of Water, they may equally press upon the Surface E F with the Water on the outside. And agreeable to what hath been said it is, that the Cylinder of Oil X Q will be something above the Surface L M, when the Tube is only immersed to the Surface Q. Since Oil of Turpentine being specifically lighter than Water, the Cylinder must be longer, to press upon the Surface G H, equally with a Cylinder of Water, no longer than from the Surface L M to G H. And if a heavier Liquor than Water were made use of, the Surface X must be more above L M than in Water, otherwise it would not press equally upon the subjacent Surface. From whence appears the Truth of the Proposition, for if the Oil be kept suspended at a different Height as the external Water is deeper, to countervail it; and if as it is raised from G H to I K, the Oil in the bottom of the Pipe is pressed out, it must needs follow, that it is pressed down by the weight of the incumbent Oil, since then the surface of the Water I K, being not equally pressed upon from without, as by the Oil, it is able to break that Surface and make its way out. But before I proceed to the following Propositions, I shall subjoin the following Advertisements. First, What we say of the Pressure of Fluids upon one another, is to be attributed to heavy Fluids in general, except some reason appears for a particular exception in some Places. Secondly, That in slender Pipes the Surface of the Liquor within, is generally above the Surface of the external, Thirdly, Small Pipes are the fittest for these Experiments, because in larger the emerging Oil passing through the Water obscures the Light of what is designed to be visible. Fourthly, We make use of Oil of Turpentine, rather than any other Liquor, because clear and colourless, and not apt to slain one's ; and as for the offensive Smell, that may be corrected with Oil of Rhodium, or any other odoriferous Oil, tho' any other Liquor may be made use of, that will not mix with Water. Fifthly, Oil of Turpentine may be tinged with Copper, to render the Phaenomena within more visible; for which reason we often employ a Decoction of Brasil instead of clear Water, or of Log-wood, or red Ink itself. Sixthly, the Figure of the Glasses may be what you please, but the Pipes must be broader or longer as occasion requires. Seventhly, The Pipes are to be filled by sucking up the Air to a convenient Height, and then stopping the Orifice above with one's Finger; but if it be too high, the Experimenter may let it out as he pleases, by admitting a convenient quantity of Air in at the Top, by gradually removing his Finger. Lastly, In such Experiments as require a considerable disparity betwixt the two mingled Liquors, we may make use of Oil of Tartar per Deliquium instead of Water, and Spirit of Wine instead of Oil of Turpentine; these Liquors being not disposed to mingle with one another; and instead of fair Water 06 we may make use of a filtered Solution of Sea-Salt, when the other is not easily got. And when we have a mind to vary the Experiment, we may make use of Oil of Turpentine along with the other two; and by depressing a Tube into them with Water in the bottom, exhibit very pleasing Phaenomena. PARADOX II. That a lighter fluid may gravitate or weigh upon a heavier. paradox 2 The truth of this is evident, since all Bodies have a tendency towards the Centre; by which they are always disposed to press downwards, tho' sometimes they have a respective Levity, as when a piece of Wood emerges in Water, yet nevertheless that relative Levity argues not that it hath no weight at all, since tho' when a Man stands in a pair of Scales and lifts up a weight, notwithstaning the Ascent of the weight he will perceive a manifest tendency of it downwards. But to make it more plain (See Plate 2d. Fig. 2.) where supposing a Cylinder of Water I G, See Plate 2. Fig. 2. to be immersed in Oil of Turpentine to the immaginary Surface E F; the Water in the Pipe I H being heavier in Specie than the Oil, it will equally ponderate upon the Surface E F as the lighter Oil K E L I, and if the Pipe be immersed deeper, the Cylinder of Water being not equiponderant with the extenal Oil, the Oil will, tho' a lighter Body in Specie, rise in the bottom of the Tube and buoy up the Water. Again the Bubble X which consists of a Glass heavier than Water and Air which is lighter; See Plate 2. Fig. 3. or partly of Water itself which is specifically as heavy, as long as the whole aggregate is lighter than Water of an equal bulk it will float, but if it grows heavier it will sink, and if any heavy Body presses upon it, which is specifically heavier than Water, by which the included Air may be compressed, the Bubble will subside, but when that Pressure is taken off, and the Air expands itself again, it will as soon emerge, the Water that was before sucked in being by that means expelled. But for a further Confirmation of this second Paradox, I shall add the following Experiment, viz. That having put a Glass-Bubble pretty well poised, into a Tube filled within a foot of the top with Water, it swum there, till a good deal of Oil of Turpentine was poured upon the Water, but then more Water being forced into the Bubble by the weight of the incumbent Oil, it presently subsided; but when part of that Oil was taken off, the spring of the Internal Air forcing the impressed Water out again, the Bubble presently immerged. And, For a further Confimation of this Paradox as well as the first, I shall add, that a Bubble swimming in a Tube, as in the former Experiment, tho' depressed to the bottom by a Wire, yet when that Pressure is taken off again it will rise up as before; but if it be held under Water till more is poured in, and till it rises about a foot above it in the Tube, the weight of the incumbent Water will depress it, but if that Water be gradually taken off, the Bubble will presently emerge. If it should be asked why in these Trials I did not make use of Oil of Tartar per Deliquium, instead of Water? I shall answer, That in such slender Pipes as the first Experiment was made in, as the Oil of Tartar flowed down one side, the Oil of Turpentine would rise on the other; which makes me wonder that Monsieur Paschall should teach, that if a Tube filled with Mercury be immersed fourteen foot under Water, if the Tube be fourteen foot long, the Mercury will not wholly run out, but continue to the height of a foot in the bottom of it; and I the more wonder at it, since probably the Impetus would make it descend; and since the like would not succeed with much more favourable circumstances, betwixt Oil of Turpentine and Oil of Tartar. PARADOX III. paradox 3 That if a Body contiguous to the Water be altogether or in Part lower than the highest level of the said Water, the lower part of the Body will be pressed upward by the Water that touches it beneath. This may be proved from what hath been delivered under the first Paradox, for wherever an imaginary Surface is beneath the real one, the weight of the Water being incumbent on all other Parts of the same Superficies, that part on which the immersed Body chances to lean must have a Proportionable endeavour upwards; and if that endeavour be greater than the specific Gravity of the immersed Body is able to resist, than it is buoyed up; and tho' the Gravity of the immersed Body is so great, as to overpower the tendency of the Water upwards, yet the tendency of that Water is not therefore to be denied, for as much as it in some measure resists the subsiding of that Body. And this may be confirmed by the Experiment tried in the second figure, for as more Oil is externaly poured on, the Water is impelled and buoyed up in the Pipe by the subjacent Oil, which could not be, if the Oil did not press against it beneath; and even when the Water and Oil are in an Aequilibrium, the latter presses upwards, in as much as it resists the descent of the Water out of the Tube. And the truth of this Proposition is equally true, whether we suspend Oil in Water or Water in Oil. And that the Water makes a resistance to Bodies that descend in it, See Plate 2. Fig. 4. will appear from the following Scheme; for supposing the Pipe E F to contain Oil specifically heavier than Water, and when the Oil and Water without were in an Aequilibrium, the Pipe be raised, drops of Oil will fall out, but much more slowly than in the open Air, where if the drop G were not specifically heavier than the Water, it would not break the imaginary Surface of the Water H I. But further, it not only from hence appears, that since as long as the two Liquors are in Aequilibrium they are not able to remove each other out of their places; but from hence we may infer, that a Liquor of an equal specific Gravity with Water, being placed in any part of that Liquor, would remain in the place assigned. But to illustrate what we have said, of Water obstructing the descent of Bodies heavier than itself, I shall add, that if twelve ounces of Lead be counterpoised in the Air, when the Lead is let down below the Surface of the Water, the Scale in the Air will manifestly preponderate; which shows that the Water hinders the descent of the other. And the resistance of Fluids to the lower superficies of Bodies may be further confirmed by observing, that Bodies specifically lighter than Water are raised by it, as Wood and drops of Oil; the Reason of which seems to be this, that there is a greater Pressure upon the lowest part N, than upon the upper part of the drop M, because that upon all the Surface K L there is an uniform Pressure of the Water A K. B L, and upon all the Parts of the Surface H I there is a greater weight of Water A H. B I, except at the part N, for there the Oil G, being not so heavy as so much Water, it is consequently unable to resist the ascent of the Water beneath it, for which Reason it is buoyed up; and the case being the same with that and any other Parallel Plain, wherever it is in its ascent, it must be by the same Reason gradually raised up, for the Oil being pressed against by two Pillars of Water, the one above and the other below, and the lower being longer by the thickness of the rising Body, than that which lies upon it, it must consequently be buoyed up, and more or less swiftly as the lower Basis presses more or less on the subjacent superficies. And for the like Reason when two pieces of stick of a different length are immersed in Water; the longest rises the fastest, for if O P were two foot high, and Q R but one, and both rested upon the same imaginary Plain, the one hath a Pillar of Water a foot longer to resist its rising than the other, and as the emerging Body rises slower, as the proportion betwixt the upper and the lower Pillar of Water is less; so thence may be deduced a Reason why in some Liquors, whose whiteness depends on the intermixture of drops, are so long a rising, the minuteness of them rendering the difference of the upper and lower Pillar of Air inconsiderable, but as these drops by moving up and down unite into larger, the difference growing more considerable, they are accordingly buoyed up in less time, and swim upon the top of the Water. And for the same Reason, See Fig. 3. Plate 2. that these Bodies float upon Water, a Cubick Inch of Wood is by its specify Gravity only so far depressed into the Water contained in the Vial A B. C D, till the Water about it makes an equal Pressure upon the imaginary Surface X W, and because the Wood is not so heavy in Specie as Water, therefore part is kept emerging above the superficies of it. But to show further, that the weight of a floating Body is equal to as much Water, as its immersed Port takes up the Room of, I shall subjoin, that having placed several Marks upon the Surface of a floating Glass, and, when it was taken off the Water, put just so much Water into it as filled it up to those Marks, by that means I found, that the weight of the Water which was sufficient to fill the space possessed by the floating Vessel, below the Surface of the Water, was equal to the weight of the whole floating Vessel, and all that was contained in it. And the same end may be obtained another way, viz. By first filling a Cistern or Pond with Water, by a Vessel of a known capacity, and then having emptied it again; for if the Vessel be placed in that Cistern or Pond, and Water put into the Cistern again till it floats the Vessel, and fills the Cistern or Pond full, as much as it falls short of the weight of Water first contained in the Cistern, so much is the weight of the floating Body. PARADOX IU. That in the ascension of Water in Pumps, etc. There needs nothing to raise the Water, but a competent weight of an external fluid. The truth of this Paradox sufficiently appears from what hath been before delivered; however to make it plainer, if possible, I shall add, that if a tinged Liquor be sucked up about an Inch into a Tube, and whilst the upper Orifice is covered with one's Thumb, it be depressed in Water till the superficies of the external Water is above the Surface of the internal, and then a considerable quantity of Oil be poured upon that, and when ones Thumb is taken off the upper Orifice of the Pipe, the external Fluids' will by their Pressure, raise the tinged Liquor above the Surface of the Water, tho' not quite so high as the Oil: From whence it appears, that a Liquor may be raised in a Tube by the Pressure of an external fluid, and that lighter than itself in Specie, which may illustrate what we have said of the rising of Water in Pumps, where by the Pressure of the Atmosphere the Water is buoyed up, when the Pressure of the incumbent Atmosphere is taken off the internal superficies by the rising sucker, and makes way for the Water to ascend within the Pipe. I took likewise a small Tube, whose Diameter was the sixth part of an Inch, and having immersed it an Inch in Quicksilver, I put my Thumb upon the upper Orifice, and kept it there till I had immersed the Tube eighteen Inches in Oil, by the weight of which pressing against the Quicksilver, it was not only kept from falling out of the Pipe, but raised a little, and as when the Tube was raised some of the Mercury would fall out, so when it was depressed the Mercury would be buoyed up, by the greater weight of the external Liquor upon it. And indeed that the Water in a Pump may be raised by the Pressure of an external fluid, will appear more fully to him that shall consider, that in the Torrecellian Experiment the Pressure of the external Air is able to raise Mercury in a Tube twenty nine or thirty Digits, which is equiponderant to a Cylinder of Water thirty three or thirty four foot high. paradox V PARADOX V That the Pressure of an external fluid, is able to keep an Heterogeneous Liquor suspended at the same height in several Pipes, tho' those Pipes be of very different Diameters. This is evident from what is represented in Fig. 6. Plate the second, See Fig. 6. Plate 2. for if the Orifice of that Vessel A B C D be closed up with a Cork, and that Cork have four holes, in three of which the Pipes are fixed, and in the fourth the Tunnel, and if, when so much Water hath been poured in as reaches to the Surface E F, Oil be poured through the Tunnel till it reaches to the Surface G H it will depress the Surface of the Water down lower, and the Oil not being able to get into the Pipes L. M. N. by its weight, it will cause the Water to rise to O P Q, the Surface of the Water, which before rested at E F, being depressed down to I K, upon which imaginary Surface the Water contained in the Tubes, answerable to their Bulk, making an equivalent Pressure with a Cylinder of external Oil of the same Boar, the Water must consequently be buoyed up to the same height in all, except the last Pipe be very small, but the difference on that account being easily distinguished, it will be no difficult matter to make an allowance. N. B. when the Oil is poured through the Tunnel, it will be requisite to put some Cotton Wool in it, to break the force of the falling stream, lest the violence of it should prejudice the Experiment. PARADOX VI If a Body placed under Water, paradox VI with its uppermost Surface parallel to the Horrizon, how much Water soever there may be on this or that side above the Body, the direct Pressure sustained by the Body (for we now consider not the Lateral or the recoiling Pressure, to which the Body may be exposed, if quite environed with Water) is no more than that of a Column of Water, having the Horizontal superficies of the Body for its Basis, and the Perpendicular depth of the Water for its height. And so likewise, If the Water that leans upon the Body be contained in Pipes open at both ends, the Pressure of the Water is to be estimated by the weight of a Pillar of Water, whose Basis is equal to the lower Orifice of a Pipe, (which we suppose to be parallel to the Horizon) and its height equal to a Perpendicular, reaching thence to the top of the Water; tho' the Pipe be much inclined towards the Horizon, or tho' it be irregularly shaped, and much broader in some Parts, than the said Orifice. As for the first part of our Paradox, it is proposed by Stevinus in more general Terms, and thus demonstrated, (See Fig. 7. Plate the second) where, supposing A B C D to be a solid Rectangular figure of Water, whose Basis E F is parallel to the Horizon, and whose height G E is a Perpendicular from the Surface of that Water, the bottom D E, E F, and F C cannot be charged with a greater weight than what is respectively Perpendicular, because none of them can receive an Additional weight from the Water Collaterally, but it must diminish the weight of Water Perpendicularly incumbent on that other bottom, else there must be a greater weight upon the Basis D E F C, than is contained in the Surface A B. C D, which is impossible. To which instance of the learned Stevinus I shall add the following. For if Oil be sucked up into the Pipe represented by Fig. 8 Plate the second, and when it is at a convenient height in the longer Leg, you nimbly stop the upper Orifice, till it be depressed so low into the Water, that the Oil is but little above the Surface of the Water, it will rest near that station, when the upper Orifice is unstopped; and if it be depressed lower than that, the weight of the incumbent Pillar of Water will force its way into the Pipe, so far as answers the weight of a Cylinder of Water of an equal Boar with the Oil contained in the Pipe, and on the contrary, if the Pipe be elevated above its first station, as much Oil will rise out of the Pipe and emerge, as answers in weight to the part of the incumbent Pillar of Water removed by that means from gravitating upon it. And to this I shall add, that tho' Water is not contained in Pipes, yet it presses as regularly upon subjacent Bodies as if it were; which will be evident, if a Vessel of the shape of the Funnel delineated in Fig. the 6th be employed, for the Liquor contained in the small Stem of that will be able to sustain the whole incumbent Water: In confirmation of which, we made use of such a Vessel, as Plate the third, figure the first represents, See Plate 3. Fig. 1. and filling the parallel Leg with Oil, and the other as well as the Ball with Water, the Oil was elevated no higher in the longer Leg, than if the less Leg had been an uniform Tube of the same Diameter; and when the Experiment was reiterated with Oil in the Ball, and Water in the long Leg, the weight of that Oil was not able to raise the Water in the long Leg to an equal superficies with itself; the Liquors in both these Experiments which was contained in the capacity of the Ball, being sustained by the concave sides of the Glass. And the like Experiment being tried with Quicksilver, which was poured into the shorter Leg C D, till it wrought almost to the bottom of the Ball, and as high in the longer Tube A B, upon an affusion of Water into the longer Leg, the Mercury was buoyed up into the Ball, till it wrought to H E G, where if more than what was Perpendicularly incumbent on the Tube C had pressed upon it, the Water would not have been able to keep it at such a height. But to confirm the second part of our Paradox, See Plate 3. Fig. 2. we made use of a Glass, such as Plate the third Fig. the second represents, and having filled the Glass half full of Water, we stopped it with a Cork, in which the Pipes there delineated were fixed, and likewise the Tunnel, the bottom of each of the Pipes, being each immersed considerably in Water, and then pouring in Oil through the Tunnel, we observed, that the Water was elevated to an equal height from the lower superficies of the Oil which pressed on the Water; in which Experiment, tho' the Pipes contained more Water by being included, yet that Water pressed no more upon the imaginary Plain, than an erect Pipe of equal Boar with the lower superficies of the Water contained in it would have done. And if Oil of Turpentine be poised in a Pipe in an erect Posture, and then by inclination a greater portion of it brought under Water, yet the external Water will raise the Oil contained in it; and the same was evident, when Oil of Turpentine being contained in three Pipes of such figures as Plate the third Fig. the third represents, for in all such cases, See Fig. 3. Plate 3. where the Pipes are in an inclined Posture, or some Parts of them larger than ordinary, part of the weight of the Liquors contained weigh upon the sides of the Vessel, and no more presses upon the subjacent Liquor, than is answerable to an erect Pipe of equal Boar with the lower Orifice, and of equal height with an erect Tube, answerable to the length of one end of that Pipe from the other. To make out what Stevinus hath asserted, viz. That if a Cylinder of Water be placed upon a subjacent Body, the Basis will sustain a weight equal to that Circular Basis, and to the Perpendicular height of it, we provided a Vessel of Laton, See Fig. 4. Plate 3. of the figure represented by Fig. twelve Plate the third, which being furnished with a close bottom C D, made of a flat piece of Wood, covered with a soft Bladder, and greased on the lower side near the edges, that leaned on the rim of Wood G H, contiguous every where to the inside of the Latin, that it might be easily lifted up from off the rim, and yet at other times lie so close upon it, that the Water should not be able to get out between them. To the midst of this bottom was fastened a long string, for a use to be hereafter mentioned; the Instrument being thus prepared, the Water was poured in at the top of the Pipe A B, which pressing upon the false bottom C D, against the subjacent rim G H, contributed to render the Vessel more close, and to obstruct its own passage, whereupon we tied the upper end of the string I K to a beam, and put so many weights into the opposite Scale, as were sufficient to raise the false bottom C D from the rim G H. And then deducting from that weight, the weight of the false bottom, and the Water contained in the broad Cylindrical Box B E C H. G D F, we found that the Pressure, which was made upon C D was much greater than what reading Stevinus would make one expect, and than all the Water contained both in the Pipe and Cylinder would have been, had it been contained in an uniform Cylinder. paradox VII PARADOX VII. That a Body immersed in a fluid, sustains a Lateral Pressure from the fluid; and that increased, as the depth of the immersed Body below the Surface of the fluid increaseth. This appears from what is represented by Plate the third, Fig. the fifth, See Plate 3. Fig. 5. where Oil being sucked up into the Pipes G F K, and they sufficiently immersed in the Water contained in the Vessel A B C D, so that the Surface of the Oil I K, may be but a little above the Water, the Imaginary Pillar of Water H G will suspend it there, but if the Pipe be raised, the Oil becoming too heavy to be kept up by so short a Cylinder, the incumbent Cylinder will force it out of the Orifice G, but if the Pipe be further immersed, the Water will raise the Oil in the Tube, and fill part of the Cylindrical cavity below it. To this Experiment I shall add, See Plate 3. Fig. 6. that having stopped the Mouth of the Vial ABCD, represented by Fig. six, Plate the third, with a Cork and Cement, and bored with a hot Iron, a hole to receive the Pipe G H, and the other E F, I stopped the Orifice G with a Cork and Cement likewise, and then pouring in Water through the Pipe E, till it risen to the Surface I, the Bubble X was so nicely poised that it swum, but as soon as by pouring in more Water the Surface was raised to K, the Bubble X subsided to the bottom: From whence it appears, that the whole Water contained in the Pipe E, presses upon the whole Water within the Glass, otherwise it could not compress the Air in the Bubble, and make it sink; and likewise that it not only presses upon that subjacent, but likewise upon those Parts that are latterally situated in Respect of it. And that not only the upper Parts of the Water, but even the Cork that is below the Surface of the Water I, is pressed by the weight of it, and obliquely too, appears, since if the Orifice G be not closely stopped, the Water will be raised through it, and if instead of a Cork and Cement, it be only stopped with one's Thumb, one may perceive an evident Pressure of the Water against it. And that the subsiding of the Bubble depended on the Pressure of the Water above it, appeared, since if part of the Water was poured off, by inclining the Vial, it would presenty emerge again. And one thing in this Experiment worthy our notice, was, that if the Glass A B. C D was not wholly filled, but the space betwixt L M filled with Air, yet the Pressure of such different Fluids may be so easily communicated from one to the other, that the Bubble would descend equally as if it were filled with Water. paradox VIII PARADOX VIII. That Water may be made to depress a Body lighter than itself, as well as to buoy it up. The truth of this Paradox will be easily made out by the following Experiments, for if a Glass Syphon, See Plate 3. Fig. 7. of the Figure represented by Fig. 7. Plate the third, be filled from H to I with Oil of Turpentine, and immersed in the Glass A B C D, till the Orifice A of the shorter Leg be under Water, if then the Orifice E be unstopped, and the whole Tube E I F G H be depressed gradually, the incumbent, Water H K will press the Oil out of the shorter Leg H G, into the longer E F. And, For a further confirmation of this Paradox, as well as the foregoing, and the second, I shall subjoin; that having provided a Pipe of the Figure represented by Fig. 8. and sucked so much Oil into it as filled the space L M N P, See Fig. 〈◊〉 I immersed it in Water, and upon the opening the Orifice O, as the Pipe was gradually depressed, the Oil was pressed out of the Pipe L M to N, and from thence to what height I pleased in the Pipe O P N. PARADOX IX. paradox IX That whatever is said of Positive Levity, a parcel of Oil lighter than Water may be kept in Water, without ascending in it. Considering that since the Surface of a Vessel of standing Water is (Physically speaking) Horizontal, the Water that presses against the lower part of the immersed Body must needs be deeper, than that which presses against the upper, and that this is the Reason why Bodies lighter than Water emerge, I concluded, that if the Water upon the upper Surface of Oil in a Tube could be so high as to balance the Pressure of that Water below, Oil might be suspended betwixt two Parcels of Water. To try the Result, I sucked an Inch of Water into a Tube, and by stopping the upper Orifice, and by that means suspending the Water in the Tube, I removed it into a Vessel of Oil, and then opening the upper Orifice till an Inch of Oil was buoyed up into it, I removed it again into a Vessel of Water, and immersed it so far in that, till the Water below the Oil was equal in height to the Water above it, in which station the Cylinder of Oil and Water being equal in weight with the Pressure of the external Water, the Oil Q. R. was suspended betwixt the Water S. R. and that below it P. Q. the Surface of the Water in the Pipe T. S. being so much above the Surface of the Water A D. as was requisite to make the Oil and Water contained in the Pipe to press equally on the Surface G. H. with the external Water, See Plate 4. Fig. 1. as Plate 4. Fig. 1. represents. PARADOX X. That the Cause of the Ascension of Water in Syphony, paradox X and of flowing through them, may be explained without having recourse to Nature's Abhorrency of a Vacuum. To demonstrate this, See Plate 4. Fig. 2. we provided a Glass Tube A B. C▪ D. of a convenient wideness, and half a yard or more in depth, as also a Syphon with two Legs F K, and K G, to which is joined a Pipe E K, and to each of the Legs of that Syphon we tied a Glass Pipe, sealed at the bottom, and having Water contained in each, to the height there delineated. Things being thus prepared, Oil of Turpentine must be poured into the Tube A B. C D, (but that it may not take up too much of the Oil, the bottom of the Vessel to X Y, may be filled with Water) till it reaches above the top of the Syphon F K G, and then by the weight of it the Water in the Pipe will be raised through the Syphon, and run into the lower Vessel H. In which Experiment the Water is raised through a Syphon by pressure, tho' at the same time there be a free communication of Air through the Pipe E K, without danger of a Vacuum. In which Experiment, if the Reason be asked, why the Water does not rather run out of the Bipe H, into G, than the contrary? It may be answered, That tho' externally the Oil is deeper upon the surface of the Water in the Pipe H, and consequently presses more upon it, yet the Tube G, on the other side, instead of having that pressure of Oil, hath a Cylinder of Water of an equal length, which being heavier than Oil, raises the Water out of that Tube more forcibly than it is raised out of the other. And for the like Reason, when once the Water is raised in Syphons, tho' there be a longer Cylinder of Air upon that end which is immersed in the lower Vessel, yet there is a greater weight on the other, because besides the incumbent Atmosphere, there is a considerable Weight of Water: But if the Syphon be above 34 or 35 Foot high the Water will not flow through it, the pressure of the external Air being unable to raise Water to such a height. And one thing observable in these Experiments is, That if when the Water is running through these Syphons, a small hole be made upon the top of a Syphon, the Air pressing upon the Water within the Pipe as well as without it, it will cease to run, tho' the hole be no bigger than one made with a Needle; which hole if it be stopped with a Needle, the pressure of the external Air will by that means be taken off, and the Syphon be rendered fit for use. PARADOX XI. paradox XI That a Solid Body, as ponderous as any yet known, tho' near the top of the Water, it will sink by its own weight; yet if it be placed at a greater depth, than that of twenty times its own thickness, it will not sink, if its descent be not assisted by the weight of the incumbent Water. To demonstrate what is contained in this Paradox, See Plate 4. Fig. 3. we must fill the Glass A B C D, (see Plate the 4. Fig. the third,) almost full of Water, the length of it being near three Foot; in which Water, if we suppose the Weight E F to be placed upon the surface G H, it will sink by reason of its specific Gravity, the Water incumbent on other parts of that Plain being not equiponderant, but if we suppose it to be placed upon the Surface I K, the Pillars of Water being above nine times as thick as it, they will counterbalance it, for which Reason were there no Water upon it, it would subside no further; and were a method contrived to keep the Water from pressing upon it, the like would happen supposing it to lean upon the Surface L M. And to show, that were the weight so depressed free from incumbent Water, it would not subside, I shall add the following Experiment; let then the Brass Body E F, See Plate 4▪ Fig. 4 (see Plate 4. Fig. 4.) be the cover of a Brass valve, the valve being fastened with Cement to the Glass Pipe O P, the Body E F, must by pulling a hair fired to the button of Valve Q close the Orifice of it, and then it being conveyed under Water a foot deep, the Cement and sides of the Glass O P, will keep the Water off the upper part of the Body E F, and consequently the imaginary Surface V W will only be pressed upon by the sole weight of the Body E F, but the other Parts of that Surface by the incumbent Cylinders of Water, so that the Body E F will be boar up without the assistance of any thing else but the Water buoying up against it, but if the Tube be raised till the Body E F be above the Surface I K, and near X Y, the weight of it being greater than the weight of the incumbent Pillars of Water, the Body will be no longer supported; but if upon the first immersion, when the Body E F is let down to the Surface R S, a weight L be suspended at it, that will not be able to sever the Body from the Valve; from whence it appears, that there is no need in our Physicomechanical Experiments to fly to a Fuga Vacui to explain the Reason why two exactly polished Marbles when contiguous are so hard to be separated. To what hath been said under this Paradox, I shall add, that when the weight L is suspended at the button Q, the Body E F will be separated before it rises to the Surface I K. APPENDIX I. Objections to evince that the upper Parts of Water press not upon the lower, Objections answered. answered. The first Objection is, that if the upper Parts of the Water pressed upon the lower, the lower would be condensed; but to this it is answered, that Water consisting of Parts tho' minute, yet very solid, it does not therefore follow, since in a heap of the powder of Diamonds, the lower are no more compressed than the superficial ones,; besides it hath not been found that Water was capable of being compressed by any force we could use. And tho' it be further urged, that Plants grow in the Sea without being depressed, yet that happens, because the Pressure is not only incumbent but Collateral likewise, and so contributes to sustain it, and the rather because the Collateral Pressure is greater than the incumbent. Another Objection is, that a Bucket of Water weighs no more when full in Water than the Bucket itself out of it, nor so much. But the Reason of this is very plain, for supposing A B C D to be a Well, (See Plate the fourth, See Plate 4. Fig. 5. Figure the fifth) in which the Bucket which is contiguous to the Plain I K, is suspended by the string E F, the Water in the Bucket G (if it be made of Wood which is lighter in Specie than Water) and the incumbent Pillar of Water not pressing upon the Surface H equally as the Water on the Surface I K, the Water below must buoy it up. And tho' the Bucket was made of something heavier than Water, yet the whole weight of it will not be perceived by the hand above, but only the Surplusage of weight which surmounts the weight of an equal bulk of Water. And tho' the Schoolmen tell us, that this Phaenomenon depends on the indisposition of Water to weigh in its own place, yet I have found, that Led being conveyed into melted Butter contained in a wooden Box, and that being suspended in Water by a Silken-thred at the end of a balance, we observed that this was as much indisposed to weigh as Water in Water, no more weight than what surmounted the weight of an equal bulk of Water, being made sensible by the balance: But when it was partly raised out of the Water or wholly, a greater weight was requisite to counterbalance it; for supposing, that part of the Bucket N to be above the Surface of the Water L M, a great force is requisite to sustain it, the weight of Water incumbent on the Surface P Q being not able to balance it, and consequently the bottom of the Bucket H, will scarce be pressed upwards half so strongly as before. But if the Bucket be raised to O, the Water being not at all contiguous to it, cannot contribute to the supporting of it. All that is further contained in this Appendix, being only a Repetition of what hath been already delivered on this subject, I shall pass it by as needless to be repeated again. APPENDIX II. Why Divers, and others who descend to the bottom of the Sea, are not oppressed by the weight of the incumbent Water. From what hath been already delivered it appearing, that Water weighs in Water, and consequently presses upon Bodies contained in it, I shall therefore, before I propose my own opinion, briefly take notice of the following. And first Monsieur Des Caries tells us, See Plate 4. Fig. 6. that if the Body of a Man were placed in the bottom of the Vessel B, so as to stop the Orifice A, he would feel the weight of the Water C B A incumbent on him, but if he were placed at B, he would not be sensible of that weight, because should his Body descend, the Water betwixt B and C would not descend with him, but supposing the Orifice A to be stopped with a solid, that would feel the weight of the Water, because it hindered the descent of the Water betwixt B and A, but since the Principles already laid down overthrow the foundation of this Explication, I shall only add, that were the matter of fact true, the Reason would be, that when his Body was at A, the Man would sustain the weight of the incumbent Water, without any subjacent Water at A, to buoy up against him, whereas at B, the subjacent Water buoys up as much as the other presses down or more. But Stevinus, Hydrostat. Lib. 5. Pag. 149. says, Omni Pressu quo corpus dolore afficitur, pars aliqua corporis luxatur, sed isto Pressu nulla corporis pars luxatur, isto igitur Pressu corpus dolore nullo afficitur. Sed Exemplo clarius ita intelliges, esto A B C D, See Plate 4. Fig. 7. aqua cujus fundum D C in quo foramen E habeat Epistomium sibi insertum, cui dorso incumbat homo F, quae cum ita sint, ab aquae pondere ipsi insidente nulla pars corporis luxari poterit, cum aqua undiquaque aequaliter urgeat. Which solution might hold, if the question was only why the Body of a Diver is not pressed down to the bottom of the Sea. But as for what he says, viz. That the equality and uniformness of the Pressure makes it less sensible I am of his opinion, for tho' in the Air the Pressure of it is not perceivable for a like Reason, yet if ones hand be applied to the top of a Receiver, and the Air exhausted, the Pressure of the incumbent Atmosphere will cause a sensible Pain. And to show that the uniformity of the Pressure, and the firmness of the Bodies of Divers, may enable them to bear the Pressure of the Water, I shall add, that having included a Tad-pole in an Instrument, See Plate 4. Fig. 8. such as Fig. 8. Plate the fourth describes, the Plug was so far depressed, that the Air in the end of the Pipe was compressed into an eighth part of the space it possessed before, so that the Pressure upon the Water was equal to the weight of a Cylinder of Water three hundred foot high, yet the Tad-pole moved up and down as nimbly as before, being not at all indisposed, tho' its Body appeared to be compressed into less room than before. CHAP. VII. An Hydrostatical discourse etc. ALL that is contained in this discourse, being chief a Repetition of what hath been before delivered in other Parts of the Author's Works, and now only repeated to obviate some Objections of Dr. More's, and the truth's laid down by our Author in his Hydrostatical Paradoxes, and Physicomechanical Experiments being so plain, and these Objections so trivial, it would but be needless to increase the bulk of the Book, with what may with more Reason be avoided. CHAP. VIII. A new Essay Instrument, and the Hydrostatical Principle it's founded on, etc. Communicated in the Transactions of June 1675. The first Section. Showing the occasion of making this Instrument, and the Hydrostatical Principle it's founded upon. A new Hydrostatical. Instrument and its uses proposed. HAving several years ago made of a Bubble with a long Stem, to estimate the specific Gravity of Metals, by its easy or more difficult immersion with them, I applied it likewise to estimate the weight of other Solids, by observing how Solids suspended at this Bubble would depress it variously according to their specific Gravities; It being a general Rule in hydrostatics, that any solid Body in Water loses so much of its weight, as a parcel of Water of the same Dimensions would weigh in the Air, so that Gold being specifically heavier than Copper, it must lose less of its weight in the Water than Copper; because proportionably the Ignobler Metal possesses the space of a greater quantity of Water, whose weight, by weighing it in that fluid, is lost in the weight of the Body suspended at the Bubble. And consequently an ounce of Gold must cause that Bubble to be immersed deeper in Water, than an ounce of Brass or Copper would, the Brass by Reason of its larger Dimensions losing more of its weight than the Gold. The second Section. Describing the Construction of this Instrument. This Instrument may be made of any Metal or other matter, which will float in the Water, without soaking it in, but the best for the uses hereafter mentioned are those made of Glass; tho' they are not so lasting as those that consist of Copper or Silver. This Instrument is made of three Parts, a Ball, the Stem, and that which holds the Pipe, The Ball consists of two Metalline Plates, each of the fashion of a Convex Glass; and the Cavity within must be so large, that the Air contained in it, may be sufficient to hold as much Air as will keep the whole Stem from sinking under Water; if the Ballast which is to keep the Vessel immersed in an erect posture is to be contained within the Vessel, the Stem ought to be hollow, but otherwise to consist of a small Cylinder without any Cavity, and of a convenient length. The Instrument I employ for Guineas hath its Ball as big as a Hens-egg, and the Stem about four or five Inches long, being soddered on to a hole in the Centre of the uppermost Convex part of the Ball; and to the Centre of the lowermost is fixed a piece of Wire to lay the Guiny upon, or a screwed stirrup to fix it in. If you have a mind to try pieces of Gold of greater weight, the stirrup ought to be fixed to a small Cylinder, upon which several pieces of Metal being fixed, and having holes in the middle, that they may be put on or taken off as occasion requires, the Instrument may be adjusted to any piece of Gold, tho' twice or thrice as heavy as a Guiny. To adjust this Instrument for the use of Guineas, it must be lightened by the use of a file, or made heavier by the addition of Ballast, that it may be sufficiently immersed in the Water without sinking, and then a mark being fixed on the Stem at the Surface of the Water, a piece of Brass must be substituted in the place of the Guiny of the same weight, or a grain or two heavier in the Air, and a mark set at the Surface of the Water, when it is immersed by that weight. In which method of adjusting, the following Particulars are to be minded. First, the Guinea must be placed exactly with its middle in the screw, that it may not incline the Tube, but let it stand erect. Secondly, Quicksilver Ballast in Metalline Instruments is apt to dissolve the sodder. Thirdly, the marks may be made of chewed Mastic fixed in small holes; or by fixing a Silver or a Golden Wire in a nick made round the Stem. Fourthly, one of the heavyest Guineas is to be made use of in adjusting this Instrument, and care must be taken that ½ of an Inch be left above the Water, because all Waters themselves are not of an equal weight, yet those circumstances vary not the success, since the difference in the immerging this Instrument in several Waters, is in considerable in respect of the difference betwixt a piece of Brass and Gold of an equal weight in the Air, it being an Inch and three quarters. Fifthly, before we can determine by this Instrument whether the Gold be good, it must be weighed in the Air, to see whether it be of a just weight, and then this will discover whether it be genuine, for otherwise we may think the Metal not good, when it only wants weight in the Air. The Explication of the Figures See Plate 1. Fig. 00. Fig. 1. A B. The Stem or Pipe. C E. The two Parts of the Ball soddered together. B C D E. The Ball itself. F. The screw. G. The stirrup somewhat out of its Place. H. The mark to which Copper of the weight of a Guinea in the Air depresses it. I. The mark to which the Gold sinks it. Fig. 2. The screw by itself to be taken off or put on the undermost Stem of the Instrument. Fig. 3. The Perforated Plates to be put upon the lower Stem as ballast. Fig. 4. The lower Stem with a Perforated Plate upon it. Fig. 5. The stirrup which my be made use of instead of the screw. Fig. 6. A. B. C. The Glass Instrument. D D D. The Coin supported by four Horsehairs. Fig. 7. The undermost Stem of a Glass Instrument, to which a screw is fastened with Horsehairs or otherwise. Fig. 8. A B C D. The Instrument for estimating the specific Gravity of Liquors. E E The Quicksilver or Water employed as Ballast. The third Section. Representing the uses of this Instrument, as relating to Metals. The first Use. Is to distinguish true Guineas from Counterfeit. The second Use. In examining a piece of Gold lighter than a Guinea; so much Ballast may be added as will make that amount to the weight of a Guinea, and if the Gold be heavier, so many of the perforated Plates must be taken off the Stem, that the Instrument may not be sunk by it, and when a Coin but a little heavier than a Guinea is to be tried, it may be convenient to place a perforated Plate upon the upper screw, so that it may lie upon the Ball, and be taken off, or lightened with a file as occasion requires. That several pieces of Gold may upon some occasions be fixed at once, the aperture of the screw ought to be wider, than what will just admit of a Guinea. If the Instrument be well proportioned, so that a piece of Gold a little heavier than a Guinea, may not depress it under Water; it may be examined without altering the weight of the Instrument. And to the method above laid down, a half Guinea may be tried by placing a true half Guinea with it in the screw. The third Use. This Instrument may be adjusted to try Silver Coins which are lighter than half a Crown, by weighing Silver in it, and marking the Surface of the Water upon the Pipe, and then observing what difference there is betwixt that, and an equal weight of an ignobler Metal in the Air. And tho' several Instruments would be more convenient for the trying of these different Metals, yet by altering the Ballast Plates, one may be made to serve the turn. The fourth Use. And by the like method an Instrument may be adjusted, to discover whether Tin be more or less adulterated with Lead, since Tin being the lightest of Metals, the Lead will depress the Instrument lower if mixed with Tin, as Gold on the contrary is the heaviest Metal, and is lighter upon the addition of another Metal. The fifth Use. It may enable us to guests at the Qualities of Metalline Mixtures, and the proportions of the ingredients, for by adjusting how much such a weight of Gold will depress the Stem, by afterwards trying how much lighter in Water the same weight of allayed Gold in the Air will be, and at the same time observing what was the proportion of Silver in the Alloy, we may be enabled to judge how much other pieces of Gold are alloyed by comparing their weight in Water with this Standard, provided they be of the same specific weight in the Air, with the Gold unalloyed. And the same measures may be taken to make an estimate of the alloys of Silver with Copper, or of Copper with Tin. CHAP. IX. Observations of the growth and increase of Metals. About the growth of Tin. I am told by the Master of a Tin Mine, that after a Tin Mine had been quite drained of its Ore, by washing and vanning about 120 years after, it yielded rich Ore again, and that a good quantity of stuff being choir drained of its Ore, and laid on a heap in the Air, in thirty years it afforded Metal again. And the same Gentleman told me, that having caused the Water which washes the Earth away from the Ore, to lay down that Earth, by stopping the current of it, till its own weight made it subside, that Earth being twelve years exposed to the Air, yielded a good quantity of Metal. And Relations agreeable to these I have received from another. Of the growth of Lead. It hath been observed, that Led Over cleared of its Metal, and laid in heaps for some years yields Metal a second time. And J. Gerhard in Decade questionum p. m. 22. says, Fessularum mons in Hetruria Florentiae civitati imminens, lapides Plumbarios habet, qui si excidantur brevi temporis spatio novis incrementis instaurantur. And Agricola, speaking of the growth of Mines in general, testifies the same; but I am told, that this happens not in all Mines. And tho' it be believed that the Reason why the passages into some Mines grow narrower, is to be attributed to the growth of the Metal, yet I am apt to believe, that it may be caused by the powerful expansion of some frozen Water in the Earth, that encompasses those passages; and whereas it is urged as an Argument of the growth of Metals, that Lead increases its weight by being exposed to the Air on the tops of Churches, yet I am inclined to believe, that it rather proceeds from a Ceruse form by corrosive Parts, uniting with the Parts of the corroded Metal, and chief for this Reason, viz. Because I have observed, that the Wood which lies about that Lead abounds with an Acid Spirit, capable of corroding Lead, and that when they have been long exposed to this Acid, a white Lead may be scraped off better than the common Ceruse, and this is found on that side the Lead which is next the Wood, and not on that exposed to the outward Air. And I have observed, that even Alabaster and white Marble will yield an Acid Spirit, so that we question whether Led fixed to the feet of Statues, may not by the help of that acquire a greater bulk, and increase of weight. Of the growth of Iron. We are told, not only by Pliny and Srabo, but Fallopius and Caessalpinus, that in the Island of Elva not far from the coast of Tuscany, Iron hath been observed to grow; and Agricola attests the like to be observed in Germany. And Johan. Gerherd. tells us, that he was informed, that not far from Amberga, the Ore exposed to the Air for some time in heaps requires Metalline Parts. Of the growth of Silver. I have been told, that Silver grows in the form of Vegetables, and in a Voyage to Pern I find the following relation, viz. That in the Mines of Potosi it is observed, that Earth that was dug out of the Grooves and Shafts, and thrown aside, hath such a propensity to the Production of Metals, that after some years it would yield Metal. Of the growth of Gold. Tho' there is no Gold to be found on the coast of Guyny in Congo, and other Parts of afric, where Writers mention it to be found, yet I am told, that in Hungary, the Master of that famous Gold Mine of Cremnitz hath observed, that the whole Mountain abounds with Particles of Gold, and that when they have cleared a great deal of the Soil in one Place of its Metalline Parts, they throw it into the hole again, and observe, that in a little time it will yield Gold as before; and Johan. Gerherd. gives us an Instance of the growth of Gold in Germany. Postscript Dr. Brown tells us, that he observed the passages in several Mines grown up, especially in moist places, and that the yellow Soil near Cremnitz yields some Gold. Whether the increase of Metals depends on the influence of the Air, or some other cause, till further and more strict Observations have been made, I shall not undertake to determine; but shall only add, that a Marchasite having been shut up in Vacuo, it acquired a Vitriolate Efforescence betwixt blue and green. CHAP. X. A Hydrostatical way of estimating Oars. Oars Hydrostatically estimated. TO help me to make an estimate of the proportion of Metalline or the Mineral ingredients of Bodies, I weighed a piece of Rock-Crystal or white Marble, first in Air and then in Water, by which I found that its weight, to an equal bulk of Water, was as 2 ¾ to 1, or as 11 to 4, and then by weighing Metalline Bodies, such as Magnets and Emeri, I found that the weight of these in Water was more than that of Crystal, the proportion of the latter being as four to one; by which Trials I was enabled to guests that these stones contain Metalline Parts in them: And by the same method I discovered Metalline Ingredients in some Bodies which are not generally looked upon as such, as Lapis Hematites, and American Talc. And as it is generally a certain sign, that a Body contains mineral ingredients proportionably as it is heavier than Crystal, so it is no less certain, that Bodies lighter than Crystal are not impregnated with a Metalline Ore, as Jet, Succinum, Sulphur Vive, common Sulphur, English Talc, Venetian Talc, and black Lead, whose weight to Water is but as 1 1●/100 to 1, and which by certain Trials I have found to be a kind of Talc. As for the advantages that may be reaped by estimating Oars, they may either respect Jewellers, Physicians, or Chemists, as when the Metalline Ingredients are but small; or Mineralists, whose business it is to extract the Metal, when by this Hydrostatical way it appears to be sufficiently impregnated. But, because there are some cruder Metalline Ingredients in some Bodies, as Antimony, Bismuth, Lapis, Calaminaris and Pyrites, which may deceive an unskilful Mineralist who estimates them this way, it may be convenient to make use of other Trials to distinguish them. And since some mineral Oars, when tried in the lump, appear to be poorly stocked with Metalline Parts, it may be of use to beat them to powder, and to separate the Metalline Parts, by washing, or else by fire; for by that means I once found, that a Metalline Ore which was wrought for Lead, afforded a sufficient quantity of Silver to answer the charge of working it, and to this caution I must add the following, viz. That since Marcasites are generally heavier than common Crystal, and by some looked upon to be plentifully stocked with Metalline Parts, because of their weight, and the glittering of their Parts, yet they may easily be undecived, by placing them in a hot fire, for by that means the Sulphureous Parts will be consumed, and leave behind them a black Calx; but tho' Marcasites abound not with Metalline Parts, proportionable to their bulk, yet I have found by experience, that some of them have afforded not only Copper, Silver, and Gold, but sometimes a quantity of running Mercury; but whether Marcasites may be of use in graduating Gold, or not, I shall leave to others to be considered. There is this Advertisement which I must not omit, and it is that tho' some are used to employ flux powders indiffently without understanding the difference of them, I have tried, that Led o'er being fluxed with filings of Mars, afforded a larger quantity of Metal, than with a due proportion of Nitre and Tartar fulminated together; but one part of good native Cinnabar, finely powdered, being mixed with a fixed Alkaly of Tartar, and the other with a different flux powder, we obtained twice as much Mercury from the former, as we did from the latter, tho' it was likewise a fixed Alkaly of a mineral Nature. Some Observations about native Gold. Observations about native Gold. Tho' I once believed, that there was no such thing as a Gold Mine, in which that Metal was predominant, yet I had a Portion of Ore sent me from the East-Indies with the spar about it, which had I broke it, I question not but that it contained Parts which were malleable without the help of the fire: one piece of this had so much Spar about it, that it weighed to an equal bulk of Water, as 2 91/100 to 1. The colour of the Spar was like white Marble tinged with a dash of yellow, and it differed from Lead Ore, in as much as that is usually so soft as to be easily cut with a knife, but this was as hard as a stone, and would yield sparks when struck with a piece of Steel; and it differed further from Spar of Lead Over, in as much as it was altogether incapable of being calcined, tho' kept in a Crucible red hot for some hours. Nor would it be dissolved in Acid Menstruums, as Spar of Lead Over may. A piece of Spar in which but little Gold was contained, being weighed in Water, was to its proportion as 2 65/100 to 1, which is but little above the weight of common Marble. But tho' there is such a thing as true Gold Over, yet I would not discourage Mineralists from seeking it in Veins of other Minerals, since it hath been found not only in Copper Mines, but veins of Tin and Lead; for in a place in Scotland several grains of native Gold have been found, near the Surface of the ground over Led Mines, some pieces of which being weighed Hydrostatically, one piece of Scotch Gold, which was native and free from adhering Spar, weighed three drachms twenty one grains, and another which had Spar sticking to it, weighed three drachms three grains, and a third of Scotch Gold weighed in Air forty three grains, in Water thirty nine. Difference 3 × 1/●. Proport. 12 × ●/● to one. But to distinguish pure Gold from impure, we are to note, that the Proportion of the finest, according to Mersennus, is as eighteen to one of Water, but according to ours, as nineteen to one. So that as it comes more or less short of that Standard we are to estimate its Purity. And thus by weighing Gold Hydrostatically, we may be able to distinguish, that Sand-Gold which is brought from Africa, or that from Guinea, from adulterated; for having once weighed a small Parcel of good, the Weight of that will be a Standard to distinguish the bad by. But since a great many ignorant Seamen are concerned in buying Gold, who understand not how to examine it Hydrostatically, I shall subjoin the following method to distinguish it Chemically, viz. By mixing a few Grains with Aq. fortis, Spirit of fermented Urine, or Spirit of Hartshorn; for if it be adulterated with Copper or Brass, a few Grains laid upon Paper, and moistened with this, will be tinged bluish green. And even rank Urine will be able to extract a blue Tincture from Brass, if made use of instead of the aforementioned Spirits; and the like success will happen with Salarmoniack dissolved in Water. There are in England such a great variety of Stones, that it would be worth while to examine them Hydrostatically, and to compare them with Crystal; for I have found near the high Road an Eagle-Stone, which was not suspected to be of English growth. And I found a kind of Magnesia near a Potter's Workhouse, which he afterwards made use of to glaze his Pots. And I was brought to a Mineral Substance, which tho' it was hard to be known of what Kind it was, yet I soon discovered it to abound with Vitriol, and that it would yield it much more plentifully than the Vitriol-Stones found near the Isle of Wight, or those made use of at the Vitriol-Works near Deptford, and elsewhere. And Ore of Bismuth hath been discovered by a heedful Eye, when common Miners knew not what kind of Substance it was when they dug it up. But this Hydrostatical way of estimating Oars may not only be made of use in judging of Mineral Substances, but those Earth's which are the Wombs of them; since, tho' they cannot be suspended by a Hair, as solid Grains of Ore, yet a Jar may be counterpoised in Water, and then being filled with such Earth's, the weight of them may be discovered, by first counterpoising them in the Air, and then having first wetted them with Water, and conveyed them into the Water in that Hydrostatical Bucket: And that this Hydrostatical way of weighing Earth's may be of use appears, since it hath not only been observed, that a red Mud, which lay at the bottom of Water, abounded with Iron plentifully, but I have observed the same in an English Ochre. And I have been told, that Diamonds, as well as Gold, have been found in a red kind of Soyl. And I have observed in England, curiously figured Crystals lodged in a Soil of a red Colour. And it may not only be of use to weigh divers sorts of Earth's in our Bucket, but also several sorts of Sands; since by a Microscope, I have discerned several Grains to appear, as if they were made of an Aggregate of Granates; and I have experienced, not only Hydrostatically, that that black Sand which is made use of in London, contains good store of Particles of a Martial Nature; but I have likewise been convinced by fluxing it, and by casting it, whilst it was melted, into the Conical Part of a Crucible. And I further observed, that ⅞ of it would be attracted by a powerful Loadstone. But a Mineral of a martial Nature hath not only been observed in Sand, but Gold on the Banks of Guiny, and on the Banks of Tagus which runs by Lisbon and Pactolus; and some hath been found on the Banks of the Rhine, and a little River which runs down from the Mountains in Savoy. But much more Gold may be got from Sand Chemically, than by picking it up, if the Sand be reduced to Glass with lethargy or Minium, and then the volatile Gold be obtained by giving it a Body fit to retain and fix it; such as Silver, out of which I have got by Quartation, out of as much vitrifyed Sand as filled a Retort, and two or three fluxing Additaments of small price, sixteen grains of pure Gold. And tho' by some it is thought strange, that there should be a necessity of fixing Gold, yet I have elsewhere made it appear, that by a small addition of another Substance, Gold may be sublimed without a naked Fire, and form several Crystals like Rubies. And if Sands, as well as Earth's and Stones, abound with Mineral Ingredients, it may be convenient to take an account where such Substances are found, and likewise to take a Sample of them, as also of the Oars of different Mines, and to try them Hydrostatically; for I have observed, that in English Lead Oars of several kinds, those in which thirty pound of Lead is only to be got out of an hundred of Ore, are looked upon as not worth working; those that yield half their weight of Metal are indifferent; and other Ore which yields from fifty five to sixty in the hundred is looked upon to be very good; but those that afford eighty Pound in the hundred, are accounted very rich; but I have not met with any that afforded more than seventy five in a hundred weight: Which Ore seemed to consist wholly of Metal, and was made up of Parts of a Cubical Figure, and much resembling Dies placed one by another. But besides what hath been already proposed, to be inquired after concerning Metalline Fossils', not only its Proportion is to be considered, but the plenty or scarceness of the Mineral, the easiness or difficulty of coming at it, as also its depth and freeness from Waters, its nearness to plenty of Fuel, its nearness to Water to drive Mills, and to transport it, etc. are to be considered likewise before one gins to work a Mine. An Explication of the Instruments employed in these Experiments, and those in the following Chapter. (aa) The Beam, See Plate 1. Fig. 00. (bb) the Dishes, (cc) the Frame to suspend the Beam, upon which (d) a sliding Socket, (e) its Arms containing (f) a Pulley, over which (g) another Pulley passes, (h) a Line fastened to (i) a movable Weight, by which the Beam is raised up or let down, (k) a Hair to suspend (l) the Body to be weighed in the Water, held in (m) the Glass Cistern, (n) the Bucket for Liquors, (o) the Box of grains, (p) the Forceps to manage them, (q) the Pile of Weights, (r) the Handle of the Balance, (ssss) the Table. CHAP. XI. Medicina Hydrostatica. FROM what is contained in the foregoing Chapter, it appearing that white Marble or Crystal may be a Standard to distinguish mineral Substances from other Bodies, I shall here subjoin the way of weighing sinking Bodies in Water. The method of weighing Bodies. And first, the solid Body to be examined, is to be suspended by a Horsehair, at one of the Scales just now described, and there to be counterpoised; then the Weights being taken out, by deducing from the weight of the Body in Air the weight of it in Water, by the Remainder divide the whole weight of the given Body in the Air, and the Quotient will show the Proportion in specific Gravity, betwixt the examined Solid, and as much Water as is just equal to it in Bulk. For Example, if the Weight of a Cubick Inch of Rock-Crystal be 1169 grains in the Air, and 738 in Water, the Remainder will be 431 grains; by which the 1169 grains being divided, the Quotient will be found to be 2 × 71/100 or near enough 7/10, for the proportion of the Gravity of white Marbles to Water. In which Direction it is requisite to observe, first, Cautions requisite to be observed. That what we have said implies, that the Body weighed must be heavier than Water. Secondly, Horsehairs are more convenient than other strings, because they are nearer to a specific Gravity with Water. Thirdly, Where the Figure of a Body disabled us from suspending it by tying a hair about it, we plaited a sort of net of Hairs to hold it in. Fourthly, So much of the Hair as is above the Water must be counterpoised by a Weight in the other Scale. Fifthly, Sometimes instead of the Scale I counterpoised the opposite with a weight of Lead, and suspended the Horsehair at the String; but when I did not take off the Scale, I caused it to be perforated in the middle. Sixthly, Care must be taken that the Water below touches not the bottom of the Scale, and that the Body be freely suspended, and wholly immersed in the Water. Seventhly, Care must be taken, that no Bubbles of Air be contained in the Pores of the Body weighed, since the success will be apt to fail in some Trials upon that account. And these circumstances being observed, it will be easy to know, by the method proposed, the difference betwixt the specific weight of other Bodies heavier than Water. It being agreeable to that Hydrostatical Paradox of Archimedes, That a Body, heavier than Water, weighs less in Water than in the Air, by the weight of as much Water as is equal to it in Bulk or Magnitude. And, The first Use of this method of weighing Bodies. By this Method we found, That the weight of Lapis Hematites to Water, was as four 15/100 to one, and by subliming it with Salarmoniack, we found by the Astringency of it, that it abounded with Metalline Parts of a Martial Nature; which was further confirmed, by observing that a grain of it turned an Infusion of Galls black Lapis Lazuli was to its bulk of Water in weight, as three to one. A Loadstone, which besides Magnetical, hath Medicinal Virtues, appeared to be as four 93/100 to one. Lapis Calaminaris was as four 169/100 to one. In which Concretes, the Medicinal Virtues seem to depend on the plentiful mixture of metalline Ingredients; but some Bodies which abound less with Mineral Substances, may be as operative, by reason of some more active Particles. But, This Hydrostatical method of weighing Bodies, Use TWO may be further serviceable in distinguishing Stones from Plants, or other petrified Substances, as Coral, which weighs in proportion to Water, as two 68/100 to one, and therefore appears to be a Stone, being heavier than Crystal. A monstrous Pearl taken out of an Oyster, which weighed 206 grains, was to Water as two 51/100 to one. A Calculus Humanus, which weighed six drams and a half, was in proportion to Water as one 76/100 to one; and another that weighed four drachms and a half, was to Water as one 69/100 to one. These Stones, tho' the productions of Distempers, have been accounted better than Oriental Bezoar in their Effects. Choice Bezoar Stones, which weighed three drachms in the Air, being weighed in Water, one of them was as one 47/100 to one; another somewhat lighter, was as one 53/100 to one; a third, which was taken out of another Stone, which being weighed in the Air weighed six drachms wanting nine grains, was in proportion to Water as one 55/100 to one: So that these have a much less specific Gravity than Fossil Stones. A third use of this Hydrostatical way of weighing Bodies, Use III may be to distinguish several Species of Bodies into subordinate Species, as the Loadstones of several Countries are different in weight; for I have observed Norwegian and the English Loadstones, to be heavier in specie, than those that came out of Italy, in which the Island of Elba abounds with Mines, whereof one entire Mass weighed a great many hundreds of Pounds. Fourthly, Use IV This method may enable us to distinguish counterfeit Stones, from those that are real and good, since when they are Hydrostatically weighed, there will appear a manifest difference, not only in adulterated Coral, but Bezoar, and other valuable Stones. Fifthly, Use V By this means we may be enabled to distinguish betwixt genuine Concretes used in Medicine, and those that are not genuine; as also whether precious Stones abound more or less with Metalline Ingredients. But tho' sometimes Stones that are transparent may not be so plentifully impregnated with Medicinal and Mineral Effluvia, yet considering the Activity and great subtlety of some Pigments, the latter may be as powerful. And that every sensible part of a Body may be impregnated by a small quantity of Pigment, will appear from the following Experiment, viz. If five grains of Zaphora be mixed with one ounce and half of Venice Glass finely powdered, and kept in fusion in a furnace with a violent hot fire, it will give the whole a fine blue colour, and if the proportion of the Zaphora be as one to six, the Glass will be too deeply tinged to make a handsome Gem. And to show further, that a small quantity of Metalline matter may be sufficient to impart a virtue to Glass and even Gems, I shall add, that eight grains of the powder of a Germane Granate, being kept in fusion with an ounce of Crystalline Glass, it gave it a Tincture like that which Steel gives to pure Glass. From what hath been said it appears, how the proportion of solid substances to Water may be Hydrostatically-distinguished; but since there are other substances which cannot be so weighed, being either subject to dissolve in Water, or not fit to be suspended by a Hair, by reason of their form, being either powders or liquids, to make an estimate of these, I contrived the Bucket formerly mentioned, and represented in Fig. 00, Plate the first, which being suspended in Water and counterpoised, we put a known weight of Quicksilver in it, by which means comparing its weight in Water with its weight in Air, and dividing the greater number by the difference of its weight in Air from what it was in Water, and which was thirty four grains, we found the Quotient to be fourteen and about 1/10, so that the Mercury made use of in this Trial was as 14 11/100 to 1, but common Mercury which is sold in the Shops we have found to weigh not above thirteen and a half to one, and indeed I have found a notable disparity in the weight of most common Mercuries, especially those drawn from Gold; for the Mercury being combined with that Metal becomes heavier than common Mercury. By the same measure we may know the specific Gravity of any Liquors which are heavier than Water, and which are unapt to mix with it, such as Oil of Cinnamon, Cloves, Guajacum, etc. And by the assistance of the same Bucket, we may be able likewise to weigh Powders, and estimate their goodness, if we put a known weight of them in the Air into the Bucket, and pour in gently as much Water as will fill up the Pores contained betwixt them, and be sufficient to expel the Particles of Air contained betwixt the small Parts of it; but in all these Trials it will be requisite to suspend the Scales of the Gibbet delineated in the preceding Figure, that the Scale may hang the steddier, whilst the Body is a weighing. But since there are several saline Bodies, as Sublimate, Mercurius dulcis, Vitriol, Rock-Allom, etc. which cannot be weighed in Water, in such cases, instead of Water, we may substitute Oil of Turpentine, which tho' it be of a different specific Gravity from Water, yet by carefully weighing a parcel of any substance which is genuine in that Liquor, it may serve for a Standard to estimate the goodness of other parcels of the same substance by, and it will be no very difficult matter for one well skilled in numbers, by comparing the specific Gravity of Oil of Turpentine and Water together, to know what proportion the Body weighed in Oil, would bear to an equal bulk of common Water. Another way which may be taken to estimate the specific Gravities of Liquors is, by making use of a Body that will subside in all Liquors but Quicksilver, for thus by first weighing that Body in Air, and then in several Liquors, and having noted the difference betwixt the solid and each of the Liquors, it is not difficult to find the specific weight of each, and the proportions betwixt them. And since it is but one solid that is compared thus to the differing Liquors; whatsoever their Number is, it will not be difficult to compare the specific Gravities of the Liquors betwixt themselves, and to discover by the weight of the first, that of any other, which ever one pleases. But in making choice of such a solid Body, as may serve our present purpose, care must be taken, that it be such as will not be subject to be consumed by Effluvia; or too large for a tender Balance; nor so big as to require too much Liquor to cover it; and lastly, it ought to be of such a Nature, that it may not be liable to be corroded by sharp and corrosive Liquors, or easily broke, but such as may be easily obtained, that what Experiments are tried with it may easily be tried by others, and communicated to Posterity. The Bodies made use of in trying these kind of Experiments, and which came nearest what we thought requisite for such Trials was, when we examined common Water, Rain-Water, Spirit of Wine, Wine, Brandy, Vinegar, and the Liquors drawn from it, Cider, Beer, Ale, Urine, Waters distilled from Vegetable and Animal substances; Amber: But to estimate the weight of heavier Liquors, we employed a Glass-Bubble, Hermetically sealed and filled with Mercury. But this being both hard to be obtained, and harder to be preserved, I made use of the following Body in such Experiments as are to be recorded for Posterity, viz. A Globe of Rock-Crystal which was suspended by a hair which passed through a small hole in it, and which we employed to discover the difference of those Liquors, which we could obtain greater quantities of, but for others we employed an Hexagonal Prism, with a kind of Pyramid at the end, and this Body being of such a Figure we were able to employ it in small Cylinders, in which a small quantity of Liquor would surround it and cover it. The weight of the Ball of Crystal we employed was to its bulk of Water as 2 57/100 to 1, and the weight of the Prism as 2 66/100 to 1. And this method of weighing Amber in different Liquors, may not only acquaint us with their specific Gravities, but also from thence we may learn to know which are most Spirituous. For tho' a piece of Amber weighed but 6 ¾ grains in Water, yet in common red French Wine it weighed 8 ½, in Nants Brandy 17 ⅛, and in rectified Spirit of Wine 34 ⅛. This Hydrostatical method of estimating, may likewise contribute to discover the strength of Acid Liquors, those that are strongest causing the solid to weigh less, as they are stronger, the greater decrement of weight proceeding from the greater proportion it contains of Salts that are not Volatile. It may likewise save the wasting of several Liquors, as Spirit of Wine or Brandy, in trying their goodness. And further it may be employed in estimating the intensive weight of Wine, Beer, Ale, Mead, Cider, etc. and distinguish their goodness, without consuming them. But Amber will not be heavy enough to distinguish the strength of Oil of Tartar per deliquium, and such heavy Bodies, since they are too heavy for it to subside in. Besides, the there may be another use made of our Hydrostatical solid, viz. To show when Menstruums are of a convenient strength. For that there is a peculiar degree of Spirituousness requisite in some Solvents is evident, since if Aqua Fortis be too strong, it will not be able to dissolve Silver, no more than if it be too weak, till it is diluted by an addition of Water; and it is much more fit to dissolve filings of crude Lead, when more dilute: So rectified Spirit of Wine is not always the most proper Menstruum for gummy Bodies, since it dissolves only the purest Resin, and leaves the Mucilaginous Parts behind, which may be as good in Medicine as the other, and further we see that Gum Arabic and Tragacanth are not so easily dissolved in good Spirit of Wine as in weak Liquors; and the like may be observed in dissolving Myrrh. To what hath been said on this occasion, there is one thing to be added, that when this Expedient is made use of in Oil of Vitriol or Tartar per deliquium, it is necessary to put something into the Scale to compensate the lightness of the Horsehairs, since in such Experiments the specific Gravity of the Liquors exceed the Gravity of the Hairs, and consequently they will be apt to buoy up the Body immersed, and misinform us in its true specific weight. To the ways of Hydrostatically estimating Liquors, we may add the following. And first, it may be done by filling a Vessel with a slender Stem successively, with different Liquors, and weighing them, as also it may be done by a Brass Cylinder, made heavier at one end than the other, by which it may be made to float, and to swim deeper or higher above the Water, as the Liquor contained is heavier; or another way is by fitting too Bubbles together with Cement, by which their Stems being joined, and the one caused to sink lowest by a Ballast of Mercury, as the other is filled with a heavier or lighter Liquor, it will manifestly preponderate. Another way proposed by Mersennus, is by weighing a Glass and a Stopple in Water, and then filling the Bottle quite full, and putting in the Stopple; for the weight of the Glass and Stopple being deducted from the weight of the whole, the remaining weight will be the weight of the Liquor proposed. But instead of this we made use of a round Glass-Ball with a Glass Stopple, which being first weighed in Air and Water, and counterpoised there, we were able to discover the weight of the Liquor contained, and its proportion to the bulk of the Liquor it was weighed in; and if the Bubble were too light to subside in some heavy Liquors, we would bring it to a just weight by a Ballast of Mercury. But since such Vessels as these are very hard to be got, and some other inconveniencies attend it, we think it less satisfactory than those other ways we made use of and proposed before. A sixth Use that may be made of these Hydrostatical Trials, Use VI is in reference to several Medicinal Bodies, for thus the Jucies' of Plants may be weighed, if when they are contained in our Hydrostatical Jar, delineated in the Figure above, they be hung at a nice Balance in Oil, instead of Water, since they are not subject to mix with it: And by this means we may be satisfied whether Juices of Plants alter their specific Gravity, when kept a good while, and after fermentation. And by this method likewise we may be able to weigh Honey, Vinegar, Verjuice, etc. As also we may compare and weigh the Juices of Fruits of different kinds, and the subordinate Species of each kind, as also the several Juices in their several states of Crudity or Maturity: But the use of this Hydrostatical Bucket being very tedious and difficult, to those that are not very skilful in making Experiments, the other will be more useful which are tried with Amber. But to what hath been already delivered on this subject I shall add, that tho' in several Trials made with precious substances, a nice Balance is requisite, yet in most cases the difference betwixt Bodies is great enough to be discerned by a Balance, not altogether so nice; for let the Balance be never so nice, there is difference in the Textures and Compositions of Bodies of the same Denomination, for which, as well as in defect of a nice Balance, allowances are easily made. But perhaps it may be objected by some, against the method I have been proposing, that since I generally weigh most Bodies in Water, it will be a hard matter to make them with any exactness, since it hath been observed, that most Waters themselves differ in specific Gravity. But to this I shall briefly answer, that I have not perceived so considerable a difference as will frustrate these Experiments, in which we require not a Mathematical, but a Physical certainty. CHAP. XII. Hydrostatical Stereometry applied to the Materia Medica. IT being usual for Physicians in the descriptions of several Parts of the Materia Medica, to signify the size of Bodies by very indeterminate Terms, I thought that they might be assisted by hydrostatics, to give descriptions much more exact and satisfactory; and for that end having made two hollow Brass Cubes, whose Cavities, being Cubical Inches, contained 256 grains, or a Cubical Inch of Water, it being a Law in hydrostatics, that whatever Body is weighed in Water, it loses so much of its weight, as an equal bulk of Water weighs, I concluded it would thence follow, that whatever solid was weighed in Water, if in that fluid it lost 256 grains of its weight, it might be said to be a Cubical Inch; and as it lost more or less, so it might be said to be of a Magnitude proportionable; for if it weighed but 128 grains less in Water, it might be said, to be of such a bulk of Water; but if it weighed 256 wanting thirty two grains, that being an eight of a whole Cubick Inch of Water, the bulk of the Body may be said to be ⅞ of a Cubick Inch. And if the Body weighs one ounce thirty two grains (amounting to 512 grains) or one ounce and a half forty eight grains (amounting to 768 grains) the bulk of the Body will be equal to two or three Cubical Inches. And if after the Division there remains a Fraction, it will not be difficult to estimate it, and to know the exact bulk of the Body, since the Cubical Inch consists of such aliquot Parts, as are easily and regularly divided and subdivided. And thus we may easily know the bulk of a Body that is heavier than Water, but if it be specifically lighter it will be a difficult matter. The method Mersennus proposes is this, viz. First, weigh the Body to be examined in the Air. Secondly, take a piece of Lead of a determinate weight, and able to sink the other Body in Water. Thirdly, weigh the Plate in Water, and the weight it loses in Water, will be the weight of Water equal in bulk to the Body weighed. Fourthly, tie together the Plate of Lead and the lighter Body, and note the weight of the Aggregate. Fifthly, weigh the Aggregate in Water, and subtract the weight of it there, from its weight in the Air, and the difference will be the specific weight of the said Body in Water. Sixthly, from this difference, subtract the formerly found specific Gravity of the Plate alone in Water, and the remains will give you the weight of the lighter Body in the same Liquor. And then dividing the obtained weight of the light Body in Water by 256 grains, and it will give you the solid content of that naturally floating Body. To illustrate this method, I shall subjoin the following Experiment. I. The Oaken Cube in Air weighs seven drachms, thirteen grains and a half. 193 ½ II. The weight of the Lead in Air, four drachms. 240 III. The weight of the Lead in Water (three drachms and a half, ten grains) 220 which being substracted from its weight in Air, leaves for its specific weight in Water.— 020 IU. The Aggregate of the two in Air is 433 ½ V The weight of both together in Water is— 162 which being substracted from its weight in Air, gives the difference of both the Aggregates.— 271 ½ VI The difference betwixt the weight of Lead alone in Air, and in Water, or which is all one, the specific weight of the Plate alone, viz.— 020 Being substracted from the difference of the Aggregates in Air and in Water, gives for the weight of the Cube proposed— which wants but four and a half of the weight of a Cubical Inch of Water. 251 ½ The same method that hath been taken with solids not subject to dissolve in Water, may be taken with Alloms, etc. Which is only by employing Oil of Turpentine instead of Water; for a Cubical Inch of that weighing 221 grains and ⅛, the difference of the weight of a solid in the Air, and in that Oil, being divided by that Number, the Quotient will give you the solid contents of the Examined Body. But to discover the weight of Bodies, which are apt to imbibe too much of the Liquor they are weighed in, we may guard them from it by a thin coat of Bees-Wax, and having first taken the weight of the Wax in Air, and then fastened it to a Plate of Lead, subtract the weight of as much Water as is equal in bulk to the Wax, and proceed with the Body contained, and the Plate of Lead as before taught; and having thus obtained the Weight of the proposed Body in Water, by dividing it by 256 grains, by the help of the Quotient we may obtain the solid contents of the proposed Body. Another way I devised for to learn the solid contents of a Body, without imbibing Water into it, was, by finding the weight of a Cubick Inch of Mercury, and also the specific weight of the Vessel, and then pouring upon the Body contained in that Vessel as much Silver as it would hold, by knowing the weight of that Quicksilver from the weight of the whole which the Vessel would contain, one might be acquainted, to how much Mercury the matter contained was equal. Having thus proposed a Hydrostatical way of trying Bodies, I shall leave it to others to contrive an Instrument more apt for such uses than I have done: And shall to what I have said add, that these kind of Experiments do not always equally answer in success, being apt to be diversified, as well by the want of uniformity in the Qualities, and specific weight of Bodies of the same Denomination, as by the difference in Water in intensely Hot and Cold Wether; as also upon the account of less exact Balances. But another reason is the difference of weights of the same Denomination, for we are told by a diligent Mathematician, that, cum omnia grana, vel semina, quae reperiri solent in atriis venalibus Lutetiae, and stateram expendisset, vix granum ullum, inter ejusdem Speciei grana grano alteri exacte respondisset, in incertis Ludere noluit. And the same Author tells us, that 688 Roman grains are but equal to 576 French grains, and this estimate of their difference by another Balance was found to be thirty six grains false: And the same Author receiving two accounts of the number of grains contained in a Roman ounce, the one told him there were 612, the other 576. And tho' our weights as well as those made use of by Gheraldus, have twenty four scruples in an ounce, yet he divided his scruples into twenty four grains, whereas we divide ours but into twenty. And Mersennus, p. 37. lib. 16. tells us, that cum autem dixi Chelinum, undecim dici denariorum, credunt tamen alii decem duntaxat, nil assero. And. To what hath been said, I shall only add, that tho' this method of weighing Bodies be not Mathematically exact, yet it comes as near Physical exactness as we can expect, and may be of use till some more nice way of Trials be found out. A Table representing not only the Weight of several Bodies in Air and Water, but their Proportions in Weight to an equal Bulk of Water. A Weight In Air in Gr. In Water in Grains. Proportion. AMber 306 12 1 4/100 to 1. Agate 251 156 2 64/100 to 1. A piece of Allom-stone 280 ¾ 152 ¼ 2 18/100 to 1. Antimony good and supposed to be Hungarian One 391 295 4 7/100 to 1. B Bezoar stone 187 61 1 48/100 to 1. A piece of the same 56 ½ 22 1 64/100 to 1. A fine Oriental one 172 60 1 53/100 to 1. Another 237 61 1 34/100 to 1. C Coral red 129 ¼ 80 ¼ 2 63/100 to 1. Crystal 256 140 2 21/100 to 1. Weight In Air in Gr. In Water in Grains. Proportion. Cornelian 148 103 3 29/100 to 1. Calculus humanus 2570 1080 1 72/100 to 1. Coco-shell 331 85 1 34/100 to 1. Native Crabs Eyes 77 ½ 36 ½ 1 89/100 to 1. Crabs Eyes Artificial 90 ½ 54 2 48/100 to 1. Calx of Led 138 ½ 123 8 94/100 to 1. Copper Stone 65 ½ 49 ½ 4 09/●●0 to 1. Common Cinnabar 802 702 8 1/50 to 1. Cinnabar of Antimony 197 169 7 3/100 to 1. Cinnabar Native 197 171 7 57/100 to 1. Coral White 336 204 〈◊〉 54/1002 to 1. Another piece fine 139 85 2 17/100 to 1. Calculus humanus 302 97 1 47/100 to 1. Copper o'er 1436 1090 4 15/100 to 1. Copper o'er Rich 413 314 4 17/100 to 1. Cinnabar Native, very sparkling 226 194 7 6/100 to 1. G Gold Ore not Rich, brought from the East Indies 1100 682 2 63/109 to 1. Another Lump of the same 1151 717 2 65/100 to 1. Granati Minera 217 147 3 1/10 to 1. Granate Bohemian 4 36/100 to 1. H Weight In Air in Gr. In Water in Grains. Proportion. Haematites English 1574 1156 3 76/100 to 1. I Ivory 173 2 83 1 91/100 to 1. L Lapis Manati 450 293 2 26/100 to 1. A Fragment of the same 218 ½ 123 2 29/100 to 1. Another 345 197 2 33/100 to 1. Another from Jamaica 2011 1127 2 27/100 to 1. Lapis Lazuli one piece 385 256 2 98/100 to 1. Led Over 686 590 7 14/100 to 1. Another Lapis Calaminaris 477 380 4 92/100 to 1. Lapis Judaicus 261 ½ 164 2 69/100 to 1. M Marcasites 814 631 4 45/100 to 1. Another from Stalbridge 243 189 4 ½ to 1. Weight In Air in Gr. In Water in Grains. Proportion. Another more shining than ordinary 287 227 4 18/100 to 1. Mercury revived from Ore Manganese a piece 321 230 3 13/100 to 1. Mineral Cornish, like a shining Marcasite 145 129 9 6/100 to 1. O Osteocolla 195 108 2 24/100 to 1. Over Silver choice from Saxony 458 366 4 9●/100 to 1. Another Piece 1120 960 7 to 1. Over Led from Cumberland Rich 1872 1586 1/● 54/100 to 1. R Rhinoceros horn 8563 4260 1 99/100 to 1. Rock-Chrystal, another Piece 256 140 2 20/100 to 1. S Saphir Weight In Air in Gr. In Water in Grains. Proportion. Seed-Pearl Sulphur vive 371 185 2 to 1. German very fine 306 152 1 98/100 to 1. Slate Irish 779 467 2 49/100 to 1. T A Piece of Talc like Lapis Amianthus 596 334 2 28/100 to 1. Talc Venetian 802 508 2 73/100 to 1. Talc Jamaican 1857 1238 3 to 1. New English Tin Ore, Mr. Hubert's. 812 613 4 8/100 to 1. Tin o'er black Rich. 1293 984 4 18/100 to 1. Another piece Choice. 2893 2314 5 to 1. Tutty a piece 104 83 5 to 1. Tin-glass 468 419 9 56/100 to 1. V Vitrum Antimonii per se 357 ½ 282 ½ 4 76/100 to 1. Vitriol Engl. a very fine piece 1093 512 1 ●8/100 to 1. unicorns horn a piece 407 195 1 91/100 to 1. THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. BOOK V PART II. CHAP. I. An account of a strangely Self-moving Liquor communicated in the Transactions of November 26. 1685. Of a Self-moving Liquor. AN Ingenious Mathematician having mixed several Ingredients in an Earthen Pot over Coals, the matter took fire, and began to blaze furiously; which obliged him to stifle the flame, and remove it from the fire; and when it was cold, he several times successively and at some distance of time observed, that the Liquor moved variously and briskly; and some seeds being thrown upon it, they form a sort of scum; part of which being removed, and the Liquor placed in a warm Laboratory, I observed the following Phaenomena. 1. The scum which remained on it being broke, part would be carried to the left hand, and part to the right, by the motion of the Liquor. 2. When it came from under the scum, it moved very briskly, as if its motion upwards had been checked by it. 3. The Liquor consisting partly of Oil, and partly of Bituminous Ingredients, their motion might not only be the better discerned, but some of those Oily Parts rising up to the top of the Liquor would diffuse themselves orbicularly, and form a great Halo adorned with the vivid colours of a Rainbow, and these would continue till they lost themselves successively under the scum. 4. The motions of this Liquor were frequently Vortical, which appeared by the motion of some Parts of the scum. And the Liquor all this while was actually Cold. 5. Some of this Liquor being poured into a Cylindrical Glass, it moved not as before, but being poured into a shallow wide-mouthed Glass, it moved more briskly and variously than before in the Earthen Vessel. 6. It moves more briskly or slow as the Wether varies in temper, and in all hath continued its motion ten days; and it continued this motion when poured out of a Vial into a convenient Glass seven or eight weeks after, but very languidly, and soon began to slacken its motion in point of swiftness; and from the first to the last time this Liquor was observed to move, it was about five Months. CHAP. II. Of the preserving of Birds, and other small Faetus'. Of preserving Birds. etc. IN order to make Observations about young Faetus', I preserved Chickens taken out of the Shell at several times, and on several days after Incubation, by keeping them in Spirit of Wine to which I sometimes added Spirit of Salarmoniack prepared with Quicklime, and that the Liquor might not be discoloured, I usually remove them twice into fresh Spirits, before I design to preserve them in it. CHAP. III. A Conjecture concerning the the Bladders, of Air found in Fishes. Communicated in the Transactions of May 25. 1675. Of the Bladders of Fishes. TO show whether a Fish moves in the Water, by expanding or by a constriction of himself, and whether the Bladder within him be contracted and expanded according to the several depths he swims at, we contrived the following Experiment, viz. To put several Fishes into a Bolt-head, filled with Water, and whose Stem is drawn out very fine, and sealed up when filled with Water; for if when the Fish sinks, the Water in the small Tube subsides, we may conclude he contracts himself; and if when he rises, the Water rises also, we may conclude that he expands himself. CHAP. iv Laudanum Helmontii Junioris: Communicated in the Philosophical Transactions of October 1674. Preparations of Laudanum. TAKE of Opium four ounces, of the Juice of Quinces four pound, cut the Opium small, and digest it in the Juice of Quinces ten days or more, than filter it, and having infused in it, of Cinnamon, Nutmegs, and Cloves each one ounce, let them infuse six days, and then having let it just boil a little, filter it, and evaporate the moisture till the Mass is of what consistence you desire, and incorporate with it two or three ounces of Saffron well powdered, and make it up into a Mass. The Dose of this Laudanum, if kept liquid, is from five to ten drops or less; and of the Pills a less quantity is required. CHAP. V Observations of an Earthquake made at Oxford, and communcated in the Transactions of April 2. 1666. Observations of au Earthquake. RIding betwixt Oxford, and a Lodging in the Country, which was four Miles off; the first two Miles it was colder than at other times all that Winter, but before I got home the Wind turned and Rain began to fall. And in an hour after I perceived a trembling in the House where I was, and soon after there happened a brisk Storm. At Brill, a place higher than where I was, the Earthquake was more sensible, the Stones in the floor of a Gentleman's House being perceived to move: This Hill abounds with several kinds of Mineral substances; and I am told that from that place the Earthquake extended itself several Miles. CHAP. VI Passages relating to the Art of Medicine. Passages relating to the Art of Medicines. THO' the following passages may be of small use to the Ingenious, and Experienced Masters, yet since they may be fervicable to younger Physicians, I shall for their Information impart them. EXPERIMENT I. A tall well set Gentleman about twenty four years old, having by a fall broke his Skull in several places, which were several times Trepaned, and large Chasms made in it by the taking away of several pieces, in about three days time he was seized with a Palsy on one side, so violently as to be deprived of motion and almost of sense, except that in his Leg he had some short remissions. And this Palsy continued about twenty four weeks, about which time his head being further laid open, they found a Splinter of a bone much like the scale of a Fish, which stuck so fast and close to the Dura Mater, that an effusion of Blood accompanied the taking of it away, but that being stopped in about three days time his Palsy began to leave him, and he is now very strong and healthy, tho' the Callus which supplies the place of his Skull be very large. From whence it appears, what great effects may spring from a very slight cause. But, besides the aforementioned Observations, it was further to be taken notice of, that the Parts whilst the Palsy continued were not only deprived of sense and motion, but were very much extenuated by a continued Atrophy, which loss of substance they acquired again upon a Cessation of the Paralytic affection. And it was further to be observed, that all the difference betwixt those and other Parts was, that they were more subject to be cold. To which we may add, that tho' he was frequently let blood, he continued to have a good stomach; nor did the affection of the Brain cause the least Vomiting, or Convulsions. EXPERIMENT II. To show the great and terrible effects of sudden Passions of the mind, I shall relate the following. History, viz. That a Woman having taken a Boy to a River side with her, which she loved very well, the Boy accidentally falling into the Water unseen by her, when she miss him she was taken with a dead Palsy, which could not be removed. EXPERIMENT III. But to show what contrary effects violent Passions of the mind may have, I shall add, that a Gentleman who was in his youth taken with so violent a Sciatica, that he could not go, but was carried to Church, and looked upon as Incurable; yet once, when he was in the Church, news being brought that the enemy was entered into the Town, (which was a Frontier Garrison,) and designed to Massacre all in the Church, they all fled and left him behind them, who being as much afraid of himself as the rest, got off his seat, and walked along like other Men, and this I received from the Person affected forty years after the said fright, who in all that time suffered not the least relapse of the Distemper. It might be of no small advantage to Physic, would Philosophers, amongst those Experiments which they lay down, as relating to what they writ purposely about, communicate those which they think of use to Physicians, though they should be less pertinent to the Subject under Consideration; for which reason, I shall for the future communicate such, desiring this short Advertisement may be my Apology. A defined Chemical Medicine. EXPERIMENT IU. Though Vomitive Medicines are not a little dangerous, yet since in several Diseases they are altogether requisite, I shall here lay down a Preparation which is as effectual, and yet safer than any other Liquor, and much to be preferred before an Infusion of Crocus Metallorum. The Preparation is this, Distil two parts of Antimony, and three of Spirit of Wine, in a Glass-Receiver, till the distilled Menstruum is succeeded with red Flores, and filtrating the Liquor through Cap-Paper, lay it up for use close stopped. It may be given from four to eight or ten Drops, in a spoonful or two of Wine, Blackcherry Water, or Spring-Water, drinking some of the same Liquor after it, to wash it down; it works very soon, and evacuates plentifully and effectually without danger. It hath had not only very good success in Surfeits and several other Cases, but cured a Person of an intermitting Fever, which put on various Types, and continued to afflict the Patient three Years, notwithstanding great quantities of the Jesuits Powder had been frequently given. But here it is requisite to add this short Advertisement, viz. That the Powder, if kept long, being apt to precipitate, it must either be made use of whilst the Liquor is fresh, or the Bottle must be shaked well when it is used. A designed Chemical Medicine. Considering the great esteem and value of Mineral Waters, I contrived a way to imitate them, by making use of Ingredients, very harmless in themselves, and likely to make no less innocent a Composition. The Trial was this, Having digested in a Bolt-head, two days, one part of Filings of Iron, with ten of distilled Vinegar, and then increased the Heat till the transparent Liquor appeared to be of an Orange Colour, we poured part of it off, lest the Menstruum being too much impregnated, the Metal should be precipitated. This Orange-Colour Tincture being kept for use, we dropped four Drops into eight Ounces and a half of common Water, which made an artificial Spa, whose Taste not only agrees with that of the Natural Spaws, but it will, like Tunbridge or the Germane Spa, turn a Tincture of gaul's Purple. EXPERIMENT V. The Bezoar Stone being a Medicine of great use, not only in malignant Fevers, but the Plague; and by reason of its dearness apt to be counterfeited, I shall add the following way of distinguishing betwixt good and bad, viz. by digesting about fifty grains finely powdered, with six drachms of Spirit of Nitre, in a digestive Furnace; for after they have been mixed some time, the Spirit gins to dissolve the Powder, and extracts a red Tincture; which being placed in a Northward Window about eight and forty Hours, shoots into Crystals, much like those of Salt-Petre. To show that the purging or astringent Qualities of Bodies, depend on the Disposition of the Patient as well as of the Agent, I shall intimate, that a certain Lady having eat a Toast with Cinnamon upon it, was so violently purged for about two days, that it brought Convulsions and a Spasmus Cinycus upon her, which was not removed in three Years. A Physician, to whom I communicated several things, sent me the following Account in a Letter from Dublin, dated Feb. 27. 1682. viz. That he found the good Effects of Ens Veneris in removing the Subsultus Tendinum, in a Febris Petechialis, which was fatal to many for about fourteen Months. The Method I took in this Fever was, if the Patient was costive, first to prescribe a Glister, and a large blistering Plaster between the Shoulders, keeping it running till the Declension of the Distemper; all this time I prescribed Emulsions of Aqua Aronis, Card. Bened. Citri, totius & Syr. Gratorum cum Aceto, Orange and Buttermilk Posset, etc. I avoid the use of all those things that quicken the Circulation of the Blood; and I rather prescribe Blistering to prevent, than cure Affections of the Genus Nervosum, because the Matter being once fixed in those Parts, they become ineffectual. A designed Chemical Medicine. Considering that the Menstruums usually employed in opening, and preparing the Body of Steel were Acids, I tried to do it in the following method. Having dissolved fresh filings of Steel in a warm place, in a sufficient quantity of Spirit of fermented Urine highly rectified per se, the filtrated solution had a taste different from all other Chalybeat preparations, and being set in a cold Window, in three days precipitated a powder of a green colour, yet the decantated Liquor by Evaporation would not in the least Cristalize. This Preparation hath effects quite different from those Preparations made by Acids, and is much more agreeable to some Persons. A designed Chemical Medicine. That I might try whether a Metalline Sulphur might be obtained from Steel, I pitched upon a Menstruum void of Sulphur, that if the Preparation should yield Sulphur, it might not be suspected to come from the Menstruum. Wherefore I dissolved Steel in Spirit of Sea-salt, and upon Evaporation obtained very curious Cristals, from which we drew by Distillation in a Retort, a good quantity of Liquor, which came over in the form of Steams, which had a very Sulphureous smell, which being rectified and mixed with Aqua Fortis would dissolve Gold, and give it the colour of Silver; which may intimate to us, how much the Vitriols of Metals may differ according to the difference of the Menstruums which dissolve them, since our green Vitriol affords Liquors different from that made with Oil of Vitriol. Besides which, it may be worth while to note, that though neither common or Roman Vitriol will dissolve in Spirit of Wine, which is Inflammable, yet our Vitriol would readily, and here it will not be unnecessary to hint by the by, that a solution of our saline Vitriol may not improbably be of use in Wounds, being a very powerful Astringent, and fit to prevent the breeding of Worms in Wounds, disposed to abound with such in cold Climates. But what we chiefly designed in this Experiment, and what is most to be taken notice of is, that the dry substance, raised by the fire, was distinguished by accidents into three kinds of substances. First, a Powder which when exposed to the Air turned yellow. Secondly, a deep coloured substance betwixt red and brown, of Parts much grosser than the former. Thirdly, a substance of a shining red, whose Parts were very fine and subtle. The Caput Mortuum was changed into a Talky substance, consisting of Lamelloe, situated and connected much after the same manner, as the thick Plates which make up Muscovia Glass. CHAP. VII. Experiments and Observations Solitary. EXPERIMENT I. A notable Comminution of Gold into Powder, that will sink in Water. A Comminution of Gold into Powder. WE dissolved a grain of refined Gold in Aqua Regia, adding about two spoonfuls of Water to the Solution, in which Mixture a small piece of Metal being suspended, it in a few days afforded a deep coloured Precipitate, which was so light that it was a considerable time in subsiding, and as easily raised in the form of Mud upon an Agitation of the Vessel; where it was to be noted, that tho' upon an Agitation the Liquor at the first seemed Opacous, yet in a little time it appeared to be of a fine Purple colour, so that the Particles of Gold were so far divided, as by being scattered through two ounces of Water to give a Tincture to it. EXPERIMENT II. A Proof of the Metalline Nature of Granates. The Metalline Nature of Granates, c. & In Confirmation of what I have elsewhere delivered, viz. That the Virtue of Gems depends on a Mixture of Metalline Juices, with the Particles of those Gems whilst in fluid forms, I shall take notice, that a Granate of a dark colour, being applied to a Loadstone, it so strongly attracted it, as not without violence to be separated from it. EXPERIMENT III. I am told by an Ingenious Gentleman, that he saw a flat Saphir in the East-Indies, which had a small Cavity in the middle of it filled with a fluid substance, which was not so apt to petryfie as the rest. EXPERIMENT IU. To prove that Fishes hear under Water, I shall here lay down a Relation which I received from an Ingenious Gentleman, who in a Garden near Genoa, observed the Gardener to assemble the Fishes in the Pond together, by a certain noise which he made. EXPERIMENT V. To illustrate and confirm what hath elsewhere been observed, concerning the various colours refracted by the minute and Parts of Solids, I shall here note, that a Globe of Rock-Crystal being sawn in two, the new superficies refracted the Rays of the Sun, so as to exhibit colours more lively than those of a Rainbow, which were refracted this way, or that, as the superficies of the Stones were differently situated in reference to the Sunbeams, and the like Phaenomena succeeded the like Trials with a Touchstone. Which Experiments may confirm what hath elsewhere been delivered, concerning colours of Bodies depending on a peculiar modification of Rays of Light, on the superficies of Bodies different from each other in other Qualities. EXPERIMENT VI. Having put into a Glass-Vessel an Oculus Mundi, whose Diameter was about a third part of an Inch, the Colour of which was white, and its figure Convex, by degrees the whole was turned brown; and in nine minute's time being taken out of the Water was Semidiaphanous, which being a gain put into the Water, and after a little less than half an hour taken out again, was almost as yellow and Diaphanous as Amber. But being for some time exposed to the Air, it began gradually to grow Opacous, and to be marked in several places with white streaks, which by degrees expanding themselves, united so as to make the whole Surface of the Stone of a cream white. EXPERIMENT VII. Remarkable Observations about Hurricanes. Observatious about Hurricanes. I am informed by the Governor of the Bermudas Islands, that these are the foreruners of them. First, at some distance from the shore the Sea would swell. Secondly, the Water about a day after would beat violently against the shore and adjacent Rocks, which could neither be attributed to Winds or Tides or any other cause; besides which it would sometimes on a sudden invade the shore successively, as suddenly subsiding again without any manifest cause, where it is observable, that as the encroachment upon the Shore is greater, the recess of the Water is proportionable. Thirdly, an unpleasant smell in the Air would preceded the Hurricane. Fourthly, long and visible streaks appeared in the Air of very different Colours, as white, blue, red or green, without the least appearance of Clouds. EXPERIMENT VIII. A Monstrous Pearl. Of a Monstrous Pearl. Yester day was brought to me a Pearl of an Orient colour, except one spot which I supposed was the place where the Umbelical Cord fastened it to the Shell, it was an Inch and a half long, and about 8/10 of an Inch broad. EXPERIMENT IX. A strange Observation about the Influence of the Moon. Observations on the Influence of the Moon. I am informed by a Gentleman, that upon a fall had several pieces of his Skull taken out, that he not only observed pricking Pains at the full of the Moon about the meanings, but likewise, that the Surgeons perceived an Intumescence, and expansion of those Parts. EXPERIMENT X. An uncommon Experiment about Heat and Cold. For a further Confirmation of our Doctrine of the Origin of Heat and Cold, Of Heat and Cold. I shall lay down the following Experiment; we immersed the Ball of a Thermoscope Hermetically sealed in a Cylindrical Vessel, which contained Oil of Vitriol, and presently cast Salarmoniack into the Oil, upon the Mixture of which there succeeded a violent Ebullition, and likewise a gradual succession of coldness, which was both perceived by touching the Vessel, and likewise by the descent of the Spirit of Wine in the Thermometer; yet this Mixture instead of a cold Effervescensce, presently upon the addition of an equal quantity of Water, became violent Hot. CHAP. VIII. A Collection of Chemical Experiments. A collection of Chemical Medicines. MY design in following Experiments, being rather to lay down such as may be instructive to the Reader, than Ostentations of my own skill, I shall give this short Advertisement, that I have upon that account rather made choice of such as are easy, than those that are difficult to be prepared, those being more proper for my design, which is to lay down Fundamentals for compiling of natural Philosophy, because they are likely to be most Intelligible; for it does not always happen, that that which is most pleasing to the Eye is most useful, for tho' Gold and Diamonds are valuable in themselves, yet a piece of Steel or Flint are in effect in some respects, of greater use to Mankind. EXPERIMENT I. To dissolve crude Gold with dry Bodies. Tho' Chemists so much boast of their Aurum Potabile, Crude Gold dissolved by a dry Body. as to think it a curious preparation, yet it is possible to make one without the help of a furnace, or so much time, after the following manner. Having ground four Parts of pure Nitre with two of Rock-Allom, and one of Salarmoniack, I put the Mixture into a new Crucible, keeping it in a moderate Heat, till the Mixture contained in it was dry, which being taken out, and presently pulverised, it afforded a Golden Tincture in highly rectified Spirit of Wine. EXPERIMENT II. Luna Cornea by Distillation. Luna Cornea by Distillation. Three ounces of Silver being put into a Retort upon six ounces of strong Sublimate, by a strong Fire the Sublimate was carried to the top of the Vessel, leaving the Silver half melted, and turned into a Semidiaphanous horny Substance, which would melt at the flame of a Candle like Wax. N. B. That if there be any Phaenomena in this or other Experiments, above what the Title promises, the Apology I make for them is, that as they may tend to the promoting of natural Philosophy as well as the other, so I was not willing to pass them by without Notice. EXPERIMENT III. Mercury growing warm with Silver. Mercury growing warm with Silver. Having gradually mixed the precipitate of Silver made with Copper, with two drachms of Antimonial Mercury in a Man's hand, till it had reduced to a yielding consistence three quarters of its own weight, we put the Amalgama which was noted to be sensibly warm during the Mixture, and of an uniform consistence, into a Glass Vial, which in two Night's time became a hard and brittle Concrete. EXPERIMENT IU. The lasting Disposition of a certain preparation of Mercury to grow Hot with Gold. I sent a Mercury to the Royal Society, which was prepared with a great deal of pains in my Furnaces, Mercury growing Hot with Gold. which being mixed in one hand with a due proportion of Calx of Gold, might be perceived to acquire a sensible Heat, which faculty it retained being Hermetically sealed in a Glass Egg ten or twelve years. And what is more remarkable is, that the Mercury being separated by Distillation, would when mixed again with Gold reiterate the former Incalescence. EXPERIMENT V An uncommon method of working upon Antimony. A particular way of working upon Antimony. In the common method of operating upon Antimony, the Air not only influencing the fire in its Operation, but also bearing up several of its Particles which work upon each other as in a Medium, I took the following method to try what effects the fire would have upon it, viz. I laid S S S of common Chalk and Antimony powdered, in an Earthen Pot, and placed it in a digestive Furnace, where it continued about twenty four hours, having taken care that the first and last Stratum should be of Chalk, and that the Layer of Antimony should be pretty thin. EXPERIMENT VI A method very uncommon of making a Calces of Gold. Calces of Gold. Preparations of Gold being usually taken for extraordinary Medicines, I shall lay down one, which is a Calces prepared without the help of corrosives Menstruums. Having dissolved Gold in Aqua Regia, and distilled off so much of the Menstruum as to leave the Gold dissolved in so much of it, as to resemble a thick Oily Liquor, upon which Inflammable Spirit of Wine. being poured, a red Calx presenly subsided; and the like Precipitation succeeded upon mixing Spirit of Wine again upon the decanted Liquor, which was very much sweetened by the first Infusion; and this Calx is not only more subtle, but milder and safer than common Preparations, and may be made yet more safe, if Spirit of Wine be soccessively poured upon it, and consumed by Deflagration, for by that means the residue, if there be any of corrosive saline Parts will be carried off; but there is one thing to be noted here, which is, that amongst this Calx there were several Particles which shined like Gold, so that there ought to be more than ordinary care in the Preparation to dissolve the Gold perfectly. N. B. This Menstruum is not only in this but several other Preparations preferable to common A R, because the Inflammable Spirit being mixed with it renders it more Spirituous. EXPERIMENT VIII. To try how much Volatile Salt might be dissolved in Water, we put a quantity of them both together in a moderate Heat, and found that an ounce and a drachm might be dissolved in three ounces of Water. EXPERIMENT VIII. Salt of Tartar being dissolved in Spirit of French Verdigrease, two or three times successively, and the Spirit being as often drawn off by Distillation, the Salt remained in a disposition to be dissolved in rectified Spirit of Wine, and apt to be brought to Fusion. EXPERIMENT IX. To make an Inflammable Spirit of Roses. A quart of Ale-Yest, being kept in fermentation five or six days together, with two bushels of Damask Roses and red Rose Buds well beaten, yielded an Inflammable Spirit being distilled per Vesicam. EXPERIMENT X. About the Chemical Analysis of Pearls. A Chemical Analysis of Pearls. From two ounces of Oriental Pearls distilled in a Retort in a sand Furnace, we obtained a black Oil which swum upon an Opacous and muddy Spirit, both being in weight about twenty three grains; and from the top of the Retort to the bottom was extended a film of Oil which was about three grains, being of a fetid smell and discolouring Spirit of Wfne with a reddish brown Tincture, the Oil and Spirit also resembled Hartshorn in smell, and the latter had all the Qualities of a Volatile Alkaly, as to turn Sublimate white and Syrup of Violets green, and to ferment with Spirit of Salt. The Caput Mortuum which was black being calcined became white, being of a hot and bitterish taste, and capable of turning Syrup of violets green. As also when mixed with a Solution of sublimate it would yield an Orange coloured precipitate. CHAP. IX. Of Strange Reports. RELATION I. I have been informed by a Physician who lived at Brussels, Strange Reports. that he hath prepared three or four Resuscitable Plants, and I am likewise told by a certain Virtuoso, that he saw two which an Ingenious Apothecary in Namur had prepared, viz. Carduus Benedictus and Camomile, and tho' Quercetan alleges, that for the production of such and their continuance, actual Heat is requisite, yet this Apothecary put the ashes of those Plants into such a Liquor, that upon an agitation of the Bottle the dispersed Particles of the ashes would convene into such an order, as to represent the Plant whose ashes they were, and that they would continue so till the Vessel was agitated a-again. RELATION II. I am informed by Chemist of good Credit, that he was not only told by a Virtuoso of Switzerland, that he had a piece of Malleable Glass, but laying it upon an Anvil, and striking it with a Hammer, he found it to receive the Impression, and to grow thinner after a few blows, though the edges were cracked like those of Silver when over Hammered RELATION III. I am told by a Pious Man who stayed in London in the Year 1665, when the Plague raged there, that in some places the Infection was so strong as to slain the very Walls, so that a Pest-House being only divided by a Wall, he perceived several spots on the Walls of his Study, he visited at least a thousand, and only took half a spoon-of Brandy about six times a day, and the quantity of a Nutmeg of the Root of Spanish Angelica, a grain of which he usually held in his mouth, when he visited Infected Persons. RELATION IU. I am informed by a Person of credit, that he distilled for a Germane Physician a certain Mineral, which he gave me a description of, which afforded three drachms of a Liquor which put into a Glass-Bubble with a neck, would upon the full Moon rise up into the neck a considerable height, which Expansion it lost as the Moon decreased. RELATION V. An ingenious Gentleman, who had distilled a certain Bismute or Tin-Glass for a Germane Prince, there being a Mine of it in his Territories, informed me that the Liquor distilled from it, being rectified would swell and subside upon the increase and decrease of the Moon. RELATION VI. I am informed by an Ingenious Person who resided in Prussia some time, that several Swallows which were found upon breaking of the Ice enclosed in it, recovered and flew about the Room when thawed, though none of them survived four days, some of them dying sooner. RELATION VII. I am informed by a Traveller that returned from Jamaica, that he saw a Silk-Cotton Tree which was twenty one yards about, which grew upon a certain Mountain; and that the ordinary sort are as large as Oak trees in England. RELATION VIII. I received the following account from an East-India Merchant, viz. That at Campar and Rakan on the East-Coast of Sumatra, there constantly happens a violent Indraught of the Sea called Bunna which approaches with a terrible noise, in three Parts, the first and last of which are more moderate than the second which is very high and terrible, and comes with such force, that no Vessel, except Anchor be weighed is able to resist it, and this Bunna constantly returns at new and full Moon. The reason of which the Relator attributes to the greatness of the Spring-Tides, which come rolling over Banks of Sand, which choke up the mouth of the River. RELATION IX. I am informed by a Gentleman, that being at Sea near the Coast of Mosambique, the Captain observing a dark speck in the Sky a distance off, takeing it for a sign of an approaching Storm, took in the sails, and tho' the Sky was for some time after calm, yet on a sudden a Hurricane arose, which turned the Ship several times round, as if it had been in a Whirl-Pool, and this Storm continued near two hours. RELATION X. I am informed by a Physician, that he saw in the Country near Armsterdam, a sort of Mercury in the custody of a Farmer, which was of a Golden colour throughout, and would if put upon the fire in a proper Vessel precipitate in the form of a red Powder. And I am likewise told by a Judicious Physician, that he saw in the possession of a Stranger, a sort of Mercury whose small Globules were of a green colour. CHAP. X. Various Observations about Diamonds. Observations about Diamonds. DIamonds being not only the most Noble but Valuable amongst Gems, it may be worth our while to consider them a little, and to relate what Observations I have been able to make about them. And, I. It is observed, that Diamonds are so much harder than other Bodies, that they require a greater force to cut and polish them than other Gems. II. It is observed by one who hath long dealt in Diamonds, that those which are now brought over are much softer than those of the old Rock. III. The Tradition is false, that Diamonds cannot be cut without being softened in Goat's Blood, the contrary being found by Diamond cutters, and an Experienced Diamond-cutter hath informed me, that he uses to polish Diamonds with the dust which he obtains by pounding of boared Diamonds in an Iron Mortar. iv Tho' it be a general received Opinion, that Diamonds have a weight proportionable to their Solidity, yet I find amongst my Experiments, that a Diamond being weighed Hydrostatically in Wattr was to its proportion of that Liquor as 2 22/23 to 1, so that it did not equal its treeble proportion of Water in weight. V I am informed that if Diamonds be Cloudy, sometimes one as big again as a Pea, will be at least four grains heavier than another of an equal size. VI The natural shape of Diamonds is uncertain, since most of them which we see are only broken pieces, whose figures are very irregular, yet I have seen some which seemed to consist of Triangles terminating in solid Angles, and I am told by one who cuts a great number, that those which are of a regular Figure are usually four corner'd. VII. It is observed, that in Diamonds there is a regular tendency of Fibers or thin Plates, which lie parallel to each other, which may be called the grain of them which way they may easily be divided, tho' not against that grain without difficulty. VIII. As to the colour of Diamonds, tho' it generally be so well known, as not to need to be described, yet in the East-Indies some have been observed to be of a pale blue colour: And Monsieur Tavernier says, he hath seen one of a very red colour, and a Relation of mine wore a Diamond in a Ring which was of a Golden yellow; besides which varieties of colours, I have observed one amongst a great many in the East-India House whose colour was green. IX. And I have seen a Diamond brought from the East-Indies, which had six Triangular sides and a Cavity in one of them, in which Diamond the Fibers might easily be discerned. And the Merchant to which this belonged, told me he had seen one brought from Borneo, which before it was Polished was black, tho' after it appeared to be a clear Stone. X. To conclude this Chapter, I shall add the following Relation, which will contenance what I have elsewhere related, viz. That the Virtue of Gems may probably arise from Metalline Tinctures incorporated with the matter of them, whilst it was soft and fluid; the Observation is, that having applied a Loadstone to a small Diamond which was pretty dull, it would not only be taken up by it, but would at a considerable distance leap up to it. To these Observations I shall only add, that there are several other Observations which are scattered up and down my Writings, which I shall not repeat here, they properly enough belonging to those writings. THE WORKS Of the HONOURABLE ROBERT BOIL, Esq EPITOMISED. BOOK V PART III. CHAP. I. Of the Original and Virtue of Gems. Of the Original▪ of Gems. THO' I am far from believing, that Gems are endowed with so many Medicinal Virtues as are usually ascribed to them; yet I believe they may have considerable Effects on Humane Bodies, which Virtues they may receive from the Intermixture of Mineral and Metalline Parts, whilst they were in a fluid form. And that precious Stones have once been in a fluid form, may be argued hence, viz. First, from their Diaphaneity; fluid Bodies being more apt to have their Parts ranged in an order requisite to transparency, than solid Bodies; as Silver dissolved in Aqua Fortis, and Led in Spirit of Vinegar, not only become transparent, but may form Diaphanous Crystals. Secondly, from their External figure; it being usual for Bodies to form more regularly and curiously shaped Crystals when in a fluid, than a solid Ambient substance; for which Reason, if a Glass-Bottle be filled with a Solution of Nitre, and the Water hath been pretty well consumed by boiling, the Salt will shoot into a Mass, whose side next the Glass answers the form of it, but that next the Water will be set with Prismatical Crystals of a Nitrous figure: And I have seen Indian Granates taken out of a lump of Heterogeneous matter, some of whose Surfaces were Triangles, others Paralellograms, etc. according the figures of the Cells they were contained in. And I have seen not only Bristol Stones, but Cornish Diamonds curiously shaped like Crystals of salt Petre: And I have likewise seen Rubies very Geometrically shaped; and amongst other Rarities, a Diamond whose Surface consisted of several Triangular Planes, which contained several lesser within them, which for the most part met at a Point, and form an obtuse solid Angle. And I have observed, that most Diamonds have angular and determinate shapes. And in favour of the Hypothesis already laid down, I shall add, that precious Stones being dissolved in a Particular Menstruum, they shoot into Crystals like those of Nitre, but insipid. And I have observed, that tho' Bristol Stones have on the upper part, six smooth sides which were so cut as to represent six smooth Triangles, which terminate like those of a Pyramid in a Virtex, yet the lower Part which was next the matter it adhered to, made it appear less transparent, and conformable in figure to the Cavity of its womb, this is more remarkably evident, when clusters of these Crystals grow out of one Mineral lump. And to this I shall further add, that I have seen a Mass which consisted of two flat Parallel Cakes, which seemed to be composed of a dirty kind of Crystalline substance; and out of each Cake there grew towards the other a great number of Stones, which having a little space about them, were regularly shaped, and of the colour of a Germane Amethyst. And I have a Stone which consists of four Parts, the lowest being like a flake of corpse Stone, only adorned here and there with very minute glittering Particles, as if of a Metalline Nature; over this is spread a thin white Opacous bed, and the third is made up of a long series of Crystals thick set, and which look whitish; and upon these which are not much thicker than a Barleycorn, lies another made up of Crystals like Amethysts, some higher tinged than others, and more elevated where they had most Room to shoot; those that were most elevated being hard enough to grate lines upon Glass. And I have found in the Cavities of concreted Stones Crystals which were set round the sides of them, and seemed to be form of a Lapidescent Juice, which was Percolated through the substance of the Stones, and form curiously shaped Crystals. And I am told by a digger, that he hath observed several clusters of these Crystals which stuck to no part of the Rock, but seemed to be hastily form in a soft Mould. But thirdly, not only the External but their Internal Texture favours our Hypothesis; since it seems to imitate that of those Bodies which have been formerly fluids: For it hath been observed, that several Particles of Salt sticking together have not only form large lumps, but Salgem and lumps of the Isle of Mayow Salt being broke seemed to be made up of the like Parts. And though a solution of Silver usually shoots into thin Plates, yet it may be so ordered, that several of these joining together may form larger Crystals, whose outsides may be finely shaped like some peculiar kind of Vitriol. And tho' transparent Bodies are usually thought to be of an uniform Texture, yet I have observed, that a thin Muscovy Glass Plate, which was so thin as to be scarce visible, might be further divided into Plates; and the like hath been observed in other Stones; and to this I shall add, that I have been able to perceive the grain of a large Grizolette with my Eye, as well as in Hyacinths and Saphires; and English Granates when they are broke, appear manifestly to be made up of flakes or Plates; and so do even Diamonds themselves, which are observed to cleave much more easily with the grain than against it, as Wood is observed to do, which is made up of an assimilated Juice which was first fluid: But it is observed in some Diamonds, that the flakes are not wholly Parallel, but in the substance of the Stone, sometimes make Angles; for which reason some of them break in pieces before they will cleave through. Fourthly, it seems requisite, that these Stones should have been in solutis Principiis, that they might be tinged with Mineral Juices. Which proposition suggests several Observations; and First, That most Gems lose their colour, or have it altered by the fire, and tho' it may be suggested, that the loss of a colour may be effected without the addition of a Pigment, by a change of the superficial Texture of a Body; (as when red Ink is beaten into a froth, or when Crystal receives several flaws in its Surface, by being suddenly cooled in Water, and becomes white, or in Cochinele, and puts on a pleasing colour, by the insinuation of the Tincture into the cracks and flaws) yet Indian Granates are observed to change their reddish for a dark and dirty Iron colour, and agates being kept a competent time in the fire became white, except where Mineral Veins ran, where it was observed, that the colour was not destroyed but changed, and became a deep red, tho' I suspected that a more lasting fire would have turned them white, and the like change of colour hath been observed in Pebbles, and other Stones, some of which losing their Transparency by Ignition, acquired a deeper colour upon their Extinction in Water. And to countenance what I have laid down, it may be further offered, that Gems are generally found near Mines, or Mineral Veins; and tho' they are not sufficiently skilled in digging Mines to discover what they otherwise probably might, yet I have seen several Amethysts which were taken out of Ground abounding with Iron and Tin Oars; and those softer Gems called by Mineralists Fluores, are often to be found in or near Metalline Veins, finely tinged with Mineral Juices, which were they in hot Countries and sufficiently hardened with the Sun, they might pass for Emaralds, etc. And I remember, that I once prepared a Menstruum no more corrosive than white Wine, which being poured upon well coloured Granates extracted a lovely Tincture from them. And Benvenuto Cellini tells us, that he saw a Ruby which was not of the usual colour but white, as also he acquaints us, that he hath seen Berils, Topazes, and Amethysts of the same colour; and Rubies and Saphires have been observed to be of the same degree of hardness, so that they were looked upon to be the same kind of Stone tho' differently tinged; and that the same kind of Stone may be differently tinged appears, since Diamonds have been observed to be yellowish, more yellow and perfectly yellow, bluish, greenish, and some as green as Emaralds'. And one who lived near the River Siam or Pegu in the East-Indies told me, he had seen Stones taken out of the Water partly void of colour, and partly of the colour of a Ruby. And besides what I have observed in agates and Opacous Gems, as to the differing colours of the same Stone; I wear a Sardoinx in a Ring, the uppermost part of which is black, the middlemost of a Chestnut, and the other of a blue colour, almost like a Turquois, and each of these of an uniform breadth and Parallel to each other, and even amongst Saphires tho' they are commonly azure, yet a white Stone hath been called by the same name, because of the same degree of hardness. And to these I shall add, that in Italy I have seen a large piece of Crystal, whose Pyramidal part was of a trnsparent green; the Vertex being richly tinged like an Emerald; but the further the colour spread from the Vertex, the more dilute and pale it grew, so that the Base was transparent and like ordinary Crystal; agreeable to which Josephus Acosta says, that Emeralds seem to grow in Stones like Crystals, and by little and little to thicken and refine. He likewise says, he hath seen some half white and half green; others all white, and some green and very perfect. And I have seen a Saphir so oddly tinged with Mineral fumes, that it might well be taken for a Chalcedonian, tho' of the hardness of a Saphir. And to show further, that solid Gems may include Heterogeneous matter in them; I shall add, that not only I but others have perceived something in the Body of Rock-Crystal, which by varying the posture of that Stone might be rendered visible; and the like hath been seen in Grisolets brought from the East-Indies: And in a hard Stone brought from thence, and designedly broke, I found several clear and transparent Crystals, which had their Points inwards, and were Arguments that they had swum in some Liquors, whose incoagulable Parts were either imbibed by the Ambient matter or penetrated it. And to illustrate what I have said I shall add, that I have not only seen a Fly in shape and size much like a Grass-hopper, enclosed in solid Amber, but variously and curiously coloured with his wings displayed. And I have seen white Amethists in which there appeared to be several lines, some of a brownish and some of a reddish colour, which looked like hairs, some lying Parallel to each other, and others more inclining; and I am apt to believe, that even Diamonds are not void of Particles of Heterogeneous matter, which is countenanced not only by odd Clouds which I have seen in a great many of them, but the different specific Gravity of those of the same Water, the difference amounting to a Carrat betwixt Diamonds of the size of two ordinary Pease. But, besides what hath been already offered, to prove that Gems have been once in a fluid form, it may be further alleged, that the Mineral Particles which they are so uniformly tinged with are convincing Arguments, since it is inconceivable how they should otherwise be so impregnated. And to what hath been already delivered; I shall further add, what is delivered by a French Author, viz. That the Stones which are found in the Earth have their Water coloured by the Earth, whether it be fat and black, or abounds with black or red Sand, and in some the Gems have been observed to be black or yellow; but tho' this Author hath said thus much which countenances our Hypothesis, yet I must not omit to advertise, that tho' he asserts Diamonds to be not only the hardest but heaviest of Stones, I must yet say, that they are not the heaviest as may be Hydrostatically discovered. But perhaps against what we have said, It may be urged, first that the figures of these Crystals are so curious, that a Plastic or Seminal Power seems requisite to the forming of them; which were it requisite, it might be answered, that that Plastic Power may be lodged in fluid as well as solid substances, since the solid Parts of Animal Bodies as well as Plants are form of liquid substances; but that the figures of these Crystals may be owing to an apt convension and coalition of fluid Particles may be argued hence, viz. Since common Salt, by the help of Oil of Sulphur or of Vitriol and Water, will shoot into Crystals with Points like Diamonds, and not unlike native Crystal in shape and transparency; but if the Quality or proportion of the Oil of Vitriol be varied, they will shoot into Crystals sometimes of one shape and sometimes of another, for the most part fively figured. And to show that the regular figure of Sea-salt contributes not to such figurations, I shall add, that having dissolved some Stony Stiriae, found in Caves or Grottoes, in Spirit of Verdigrease, and evaporated the clear solution in a digestive Furnace after the ordinary manner, it yielded rather a coagulated Mass, than any thing like Crystals; whence it appears, that a concourse of circumstances may be sufficient to determine the figures of consistent Bodies, made of fluid ones; especially since when I allowed a longer time for the fluid to shoot in, it afforded a good number of distinct Crystals; long, transparent, and curiously shaped. And not only the external figure of Crystalized Bodies may be accounted for, without he help of a Plastic Power, but their internal Construction likewise, since divers Bodies upon a slow coalition will form Concretes, some of which will consist of streaks, and others of flakes; as lumps of Salarmoniack, which tho' a factitious Body, when broke will appear to be full of streaks, like those Stiriae observed in petrifying Water. And I have made artificial Concretes of Salts alone, or of Salts or Minerals, as Stones, or Antimony which look very like Talk, being white Bodies made up of a multitude of streaky Particles, lying long ways one upon another as in that Mineral, and I have not only found Concretes shaped like Rhomhus' or Lozenges, composed of a multitude of flat and extremely thin Plates, but have imitated such by Art. And I have observed, that tho' generally Crystals of Silver form flakes seemingly simple like scales of Fishes, yet when they have shot leisurely they are Geometrically enough shaped, and made up of thin flakes sticking one to another. And Tin-Glass which naturally consists of a multitude of shining and polished flakes, will, tho' beaten to Powder, and melted, upon its Refrigeration form several broad and shining flakes, which lying one upon another, cross each other at various Angles, as the matter happens in several Portions to be variously refrigerated. And the like instances may be observed in some Mixtures of Copper, Iron, and other Minerals; and very conspicuously in good Regulus Martis Stellatus, whose internal structure appears upon breaking of it, to be made up of shining flakes, almost of a specular Polish. And tho' whilst we are looking on some Concretes, the Stony Stiriae in some places have a streaky and in others an angular Configuration, yet I have seen several of them made up of Parts confusedly jumbled together, and if there be a due disposition in the components Parts to such Configurations, they may be brought to Concretes in a far shorter time than any one would expect or believe; so that a solution of Silver being heated hot, and removed suddenly into cold Water, one might not only very easily, but plainly see the Silver shoot with ones naked Eye; but even a strong Solution of Salarmoniack, or some Urinous Spirit, being spread upon the outside of a Glass in which a frigorifick Mixture is contained, will in less than a minute of an hour be coagulated into Crystals of a determinate figure, according to the Nature of the Liquor that afforded it. But if against these instances it be urged, that tho' they are taken from saline Bodies, which are for the most part disposed to convene into smooth Surfaces, and Angular shapes, and are easily wrought on by External Cold, yet it may seem strange, that the figure of a Mould or Womb should alter the Internal Construction of solid Minerals and Gems; but that it may is evident, since, tho' Tin-Glass consists of several smooth and bright Planes, which sometimes meet, and sometimes lie across each other, at very different Angles, yet having beaten a sufficient quantity of it to Powder, and when it was melted cast it into Iron Moulds, whose Cavities were each an Inch in Diameter, it form a Bullet, which when varily broke seemed to be made up of a multitude of shining Planes, so shaped and placed that they wrought every way like so many Radius' of a Sphere tending from a Centre to the Circumference, so that they seemed gradually to decrease, as they were removed further and further from the Circumference. But if the melted Tin-Glass was permitted to cool in a Crucible, the hardened matter would form several Planes irregularly and confusedly associated together. And the like Experiment being tried with Regulus of Antimony it succeeded, tho' not so uniformly as with Tin-Glass: And melted Sulphur being hardened in the same Moulds, the Concreted Mass seemed when broke to consist of flakes like Straw's lying Parallel to each other: But how the flakes of Tin-Glass came to be so regularly situated; and whether the outside being first condensed, the contiguous Liquor was connected by apposition, successively as it moved within the crusted Surface, or whether it was otherwise effected, I shall not now stay to examine; but to what I have said I shall add, that having broke several Marchasites of a peculiar sort, I found them to consist of several rows of Planes reaching from the inermost Parts to the External Surface; and in those which were somewhat Cylindrically shaped on the outside, these Ranks of Gold coloured Particles, in the several Planes of the broken Mineral seemed like Semidiameters issuing out from from a row of Physical Points, conceived to be placed on an Imaginary Line; lying almost like the Axes of a Cylinder between the apposite ends; as if the Wombs wherein those Marchasites were found, contained the fluid matter as in Moulds, and as if it Concreted there, as Tin-Glass or Regulus did in the Moulds. But tho' from hence it may appear, that tho' the figures of such Concretes be curious enough, yet they may easily be accounted for without a seminal Principle, yet I find not the uniformity of the figrue always so great as is imagined, but rather to depend on the different Figure and Texture of the Wombs they are contained in; for comparing American, African, and European Granats together, I found that one which weighed eleven grains and a half, though it seemed to have been coagulated in a fluid Medium, and to consist of twelve Plains, at the concourse of two or three of which it seemed to have been broken off from the Root or Womb, yet it was not of the Dodecahedron of Geometricians; for whereas that consists of twelve equilateral and equiangled Pentagons; almost all the Planes that made up our Granate, were quadrilateral, and not of a regular shape or Magnitude; for one of them seemed to have five sides; others resembled a Rhombus, some a Rhomboides▪ but most were a little bigger than the Trapezia But, besides the want of uniformity in these Stones, I observed amongst Cornish Diamonds, that some of them were curiously and Geometrically shaped like Rock-Crystal, having each six sides, whereof every two that were opposite were equal to each other; and tho' the Stone had a Pyramidal Termination, made up of several resembling and curiously figured Planes, that terminated in a solid Angle or Apex, yet the greatest number of the Titular Diamonds were made up of very irregularly shaped Stones; for tho' most of them had six long Planes, yet the opposite were most of them irregular and unlike; and tho' the Apex was made up of Planes apart usually Angular, yet being compared with each other they were far from being uniform; tho' it appeared that they shot in a fluid Ambient, except at the bottom where they were fastened to the Rock. And I have observed a great irregularity in the Area of the Superficial Planes, or their figures, or both, in Diamonds brought from the East-Indies. Having shown that the figures of Stones are far from discountenancing our conjectures of their Originals, I shall proceed to show, that they help to confirm them; since I have seen a small Cornish Diamond so bedded in a large one, that it left a Cavity in it when separated, and on the contrary I have sometimes seen a large one so joined to a smaller as to form a Cavity within it, which is a likely Argument, that the one being first hardened, afterwards a soft matter was collected together, and being contiguous, hardened in such a form as to contain part of the other in the Cavity, which was form whilst the one was fluid, and the other was hardened; which may be illustrated by considering, how Nitrous or Aluminous Salts fasten themselves about pieces of sticks, and leave a Cavity proportionably to the solid contained: To which I shall add, that I have seen a Stone which was taken out of a Silver Mine, which had coagulated about the Branches of a Silver Wire, which was produced by Nature in the Mine. Another Argument of the fluid state of Gems, and their Impregnation with Mineral Stems, may be drawn from their Specific Gravity, for whereas common Rock-Crystal is to its bulk of Water as two and almost two thirds to one, the weight of an American Granate was as four to one. And tho' by this method a tinged Gem hath not so great a difference in its proportion to Water, yet it may nevertheless be impregnated with Mineral Particles, for I found by Hydrostatically weighing Water impregnated with Iron, that it was not much heavier than common Water. Another Argument may be drawn from the Medicinal Virtues of Stones, and the Metalline or Mineral substances, as well from Opacous Stones as Opacous Gems, etc. as the Turquois, the Onyx, the Sardonix, etc. as also Cats Eyes, Opates, etc. And indeed I much question whether Diaphaneity depends on the essence of a Gem; since it may rather proceed from the Position of the Parts of a Pigment, and the situation of the Pores in reference to the Beams of Light: But waving a further consideration of this matter, I shall rather subjoin, that precious Stones and even Diamonds themselves, have sometimes great clouds, which makes them in those Parts almost Opacous, without out being less of the Nature of true Diamonds. And it is observable that Cornelians and agates are some of them transparent, and some of them Semidiaphanous, as the Portion of the Mineral Pigment is greater or less, or as it is more or less inconveniently mixed. And I have seen even a Sardonix transparent, and on the contrary, figured Granates which were both of them Diaphanous: And I have some by me of several Countries, which tho' they are in some places Diaphanous, yet in the main they are almost as dark as ordinary Stones. And I question not, but that if the Glassy Nature of Gems did not render common Menstruums inaccessible, Mineral Particles might be extracted from them; and when they are considerable, I question not but that they may be obtained from solid and transparent Gems; for having kept Granats in a hot Crucible till they changed their colour and afforded a very fine Powder, that being digested with rectified Spirit of Wine, afforded a curious Tincture; and burnt Granats gave Aqua Regis a Tincture, which in some measure resembled a solution of Gold; but a drop of the Liquor being put to a great many drops of Tincture of Galls, it turned them as black as Ink, if not blacker. And the like measures being taken with Granates which were looked upon by some to be Rubies, the Tincture coloured an Infusion of Galls not quite so black as the other; but a white Powder was precipitated at the same time; and by the use of an urinous Spirit a reddish substance, which being dried in the Air form Bodies like Moss, and here and there small Mushrooms prettily coloured. And from other Granates I obtained a Tincture, which after evaporation did in the Cold afford saline Concretions, but so small that their figures could not be determined. And probably, were trials made, other Mineral Concretes might be wrought on by appropriated Menstruums, for tho' the Spar that is found in Lead Mines next the Veins of Ore be Semidiaphanous, and usually breaks in smooth and Glassy Superficies, and looks like a Talc, and also for the most Part is made up of figured Particles shaped like Rhombuus' or Rhomboides, yet I found it was a more open Body than Talk, being dissolved in Spirit of Salt, without the assistance of Heat. But I am apt to believe, that besides the methods already mentioned, there are other methods to discover the Metalline Ingredients of a Body, by Fusions and proper Additaments. And to conclude this Chapter, I shall subjoin the following Experiment, viz. Having dissolved Stony Stiriae of petrifyed Water, in Spirit of French Verdigrease, and after a gentle Evaporation, placed it in a cool place, it yielded ●…stals, figured much like those of pure Nitro●, 〈◊〉 some of this Stony solution being mixed wi●● a solution of Copper, they did not precipitate each other, but upon Evaporation yielded Crystals transparent and colourless, and that were richly adorned with a greenish blue Tincture of the Metal. CHAP. II. Containing a Conjecture about the Causes of the Virtues of Gems. FROM what hath been elsewhere, and in the preceding Chapter laid down, it appears, that the Earth does not only abound with several Mineral and Metalline substances, a great many of which are undiscovered, and a great many already known, but also that several Mines are furnished with Water, which being impregnated variously, may be no dispicable Menstruums, but may likewise concur to the Production of Mineral Bodies, and not only serve as corrosive Menstruums, but pure Solvents to Mineral Earth's. And that common Water is able to impregnate itself not only with Saline but Mineral Parts, is evident from the various tastes of Waters, and their uses; some being fit for brewing; others for washing; some for dying particular Colours, and some to temper Steel; and others again for other uses: And amongst the most remarkable ●…ies are Thermae and Acidulae reckoned up by various Authors, as also Salt Springs, and those Waters of Hungary and other Parts, which yield a Vitriol, which is a substance compounded and decompounded, containing a saline, a Sulphureous, a Metalline, and an Earthy Part; and if Water may be thus impregnated with Metalline Parts, it is no difficulty to apprehend how a Lapidescent Humour, being sufficiently mixed with and proportioned to it, may be coagulated into Stony Stiriae, and from such like Coalitions may arise those precious Stones, and transparent Gems; for the Virtue of specific Juices are so powerful, that I have seen Vegetable substances sufficiently hardened by them to grave on Iron; and I had a substance which I looked upon to be a petrifyed Gum, which was hard enough to grave on Glass. And if the Parts of Minerals may thus, by being dissolved in Water, be mixed with a petrifyed Body, by this means Gems may not only be impregnated, but thence receive their Medicinal Virtues, as the Nature of the Mineral is different in Qualities and abounds in Quantity, which Original of their Virtues may be rendeed probable, not only by what hath been said in the foregoing Chapter, but by their different colours. And that their Impregnation with Mineral Parts, ennobles them with Medicinal Virtues, is evident from the Testimony of Experience, and is rendered probable by the Effects of a Loadstone, which though a much harder substance than some Gems, emits Effluvia very copiously, and hath not only manifest Effects on Iron, but Humane Bodies. And even those Pebbles with which they sergeant Diamonds, have been caused in a trice to emit copious and strongly scented Steams; and even Diamonds the hardest of Gems, may by rubbing be caused to emit Electrical Effluvia. And tho' it be thought by some, that the digestion of a Man's Stomach is not able to extract the Metalline Parts, yet there may be a greater Congruity betwixt the Juices of our Bodies, and the Mineral substances with which they were impregnated, than we are ware of; besides we see that the Stomach hath manifest Effects on Chalybeate Preparations, and even crude Steel itself. And I have obtained a Tincture from several hard Bodies, and even Gems themselves, by a Liquor distilled from a Vegetable substance, as temperately qualifyed as Bread. And that the natural Heat of our Bodies, may contribute to the extracting of the Virtues of precious Stones, I am persuaded, since it makes an evident alteration in the hardest of them, so as to render a Diamond Electrical; and I have had one which by warm Water would be excited to shine in the dark. And indeed it is not altogether improbable, that Gems having the most subtle Mineral Steams in them, being not dispersed by the action of fire, they may be more Effectual considering their quantity, than Preparations of Metals which have undergone a Fusion. And their Virtues may sometimes be much different, upon the account of a great quantity of Mineral Particles, since Vunzerus tells us, that amongst those Stones which are called Nephritick Stones, some are much more effectual than others, besides the petrifick Juices themselves may have distinct natures, and peculiar Qualities, upon the account of their Coalitions with Adventitious Liquors. And if petrifying Liquors may have such manifest effects on several Bodies one would think indisposed to petrify, why may not such a Liquor subdue transparent Minerals abounding with Saline, Sulphureous, and Bituminous Bodies, which being excited may emit their most subtle Parts; and as in the Earth there are severl Bodies compounded by the action of Subterraneal fires, those petrifyed may enable the Body with correspondent Qualities; on which occasion I here subjoin, that I have seen a saline substance which was form in the Bowels of the Earth, like that which is artificially made. And I have seen Volatile Salts and Sulphurs shoot into transparent Crystals in a fluid Medium after Distillation, which have been more curiously figured than several Gems. And if it be objected in disfavour of the Medicinal Virtues of Gems, that they grow no lighter when they are said to emit Effluvia, I shall add, that, not to urge that the Antimonial Cup impregnates Wine without losing of its substance, and that Mercury will give Water a Virtue of kill Worms, by being boiled in it, tho' by these means it loses nothing of its weight, I shall rather demand how it appears, that Bodies grow no lighter by the loss of their Effluvia. And tho' in some cases the Gem may be lighter than Crystal, yet it is no argument of their more languid Effects, since the specific Gravity of those Bodies they are impregnated with, may be of a saline Nature, and specifically lighter than Crystal: And I shall in favour of this add, that I have several times made Bodies colourless like Crystal; and curiously and regularly figured, which were of a compound Nature, and abounded with an easily separable and strongly scented Sulphur. And on this occasion I shall further add, that tho' when Gems are specifically heavier than Crystal, it is an Argument of a Metalline substance mixed with them; yet sometimes those mineral Particles may be so spirituous, as not to increase their specific Gravity, for I have seen a ferruginous Water, which, tho' strongly impregnated, was little heavier than common Water. And now, if, together with what hath been delivered in this Chapter, we reflect on what follows concerning the Atmospheres of consistent Solids, and the efficacy of Effluviums, it will not be absurd to ascribe to precious Stones some Medicinal Virtues, especially to those that disposed to emit copious Effluvia. And to show that what we have delivered, may not only be applied to transparent but opacious Gems; and to render our Hypothesis not only probable, but possible, I shall intimate, First, That I have seen lapidescent Juices so penetrating, as to turn several Animal and Vegetable Substances into Stone; amongst which, one was a new Cheese, which could be distinguished no otherwise from another Cheese, but by its stony Hardness; and I have a piece of Wood petrified, which retains its grain, and is hard enough to grave upon Iron or Glass, and to resist the action of the Fire, and likewise to strike Fire like an excellent Flint. But to render this Hypothesis further probable, I shall subjoin the following Arguments. And, First, It appears from the Method taken, to weigh Bodies in our Medicina Hydrostatica, where White Marble was proposed as a Standard, to determine whether Metalline parts were in Bodies or not; for a piece of White Marble being in proportion to its Bulk of Water, as 2 72/100 to 1; and Bloodstone, as 5 2/10 to 1; a Loadstone, as 4 and 6/10 to 1; Lapis Calaminaris, as 4 7/10 to one; and Lapis Tutice as 5 to 1; It follows that those must proportionably be impregnated with Mineral Parts, heavier in specie than Stone; and for that Reason I have found some Stones of the same kind specifically heavier than others, as they were impregnated in Solutis Principiis, more or jess with mineral Parts. But it will not be amiss here to advertise, That some Stones lighter in specie than Fossils', may be compounded with mineral Parts, and thence deduce their Medicinal Virtues; and others may be impregnated with mineral Parts, lighter in specie than Marble, and consequently their mineral Nature cannot be Hydrostatically determined as yet, which is to its Bulk of Water, as 1 22/100 to 1, and yields no inconsiderable Proportion of Oil. A Second Argument for the Confirmation of our Hypothesis, may be deduced from the Necessity of it, to explain several Phaenomena, as why Diamonds and other Gems should be included in Rocks or Clusters of hard Stones, which must be soft, or could not, at the first, admit a hard Gem to lodge amongst their Parts; and I shall further urge the Necessity of it, from several Gems which I found in an odd kind of Mineral, sent me from an American Colony. And it is not improbable, that Opacous Gems are petrified Earth's, since they vary so much in their Dimensions, so that I have heard of a Spleen-stone which weighed 80 Pound weight. And I have seen a Medicinal Stone, which being sawed asunder, its internal Parts were full of Cavities; whence it appeared to be made up of porous Earth petrified, and not of an indurated Liquor. From our Hypothesis the following Phaenomena may be explained, viz. Why sometimes one part of a Gem is tinged with a Metal, and another is not, since in making Artificial Gems, the Mineral Pigment hath tinged one Part without discolouring the other. And I have now by me a lump of petrified Matter, which consists of several Stones, which though first petrified apart, and afterwards joined together by a petrescent Liquor, bear an uniform polish, without discovering betwixt their Parts the least Commissures; and an acquaintance of mine discovered several lose Stones, where this was found, which were separately of the same Nature, and afterwards hardened into stony Masses, by the intervention of a petrescent Liquor. And I have an Agate by me, which seems to consist of several Layers of Clay or Earth, lying parallel to each other, and petrified partly into Transparent, and partly into Opacous Stones; and to favour this conjecture, I shall add, that I have seen several Layers of mineral Earth's one upon another, within the compass of an Inch, which lay in different postures, in reference both to the Horizon, and each other; and sometimes the exterior ones successively surrounded the interior; and several of these have been found in a small compass of Ground; and by a like Method, differently coloured Chalcedonians and jasper's may be accounted for. And from hence may be deduced a Reason why Marchasites and Flints, Wood and Shells, have been found enclosed in other hard Stones. And on this occasion I shall add, that Stones which were partly Diaphanous, and partly Opacous, being calcined, the diaphanous Parts became White; and some others which were before tinged, had their Parts heightened so, as after Calcination to be of a rich and permanent Red; and this difference of Colours was not only remarkable in the thin Layers, but in the specks, and irregularly shaped Clouds, whether Greenish or Bluish. And to illustrate an Observation formerly made on Diamonds bedded one within another, I shall urge what is observed in Cryftalizing Salts, where, as well as in a Metalline Solution, I have observed, that when a number of Crystals had shot after the first Evaporation, several successive Layers shot upon those; in the latter of which Solutions, the Crystals of one Layer were not only fastened to the others, but differed considerably, as well in their Shape as Postures. In this Metalline Solution the Mineral was only one, and the Menstruum simple; but had the first been Compound, there would have been a greater diversity, as likewise Crystals of a compound Nature; as when a Solution of Salt-Petre and Sea-salt in Water is set to crystallize, where besides Salts of resulting Figures, a considerable part of the Sea-salt coagulates in the Form of imperfect Cubes about the Bottom, before the nitrous Particles shoot into Crystals of their own shape. And I shall further add, That Crystallization may not only be promoted by Evaporation, but by soaking part of the Water up either by immersing it, or by placing dry Earth under the Solution, or some other porous Body. And by some Analogy to these Instances, we may conceive how some of the superfluous Moisture of a Petrescent Liquor, being dispersed, the remaining may be more apt to coagulate; but by a moist Season or supervening Cold, the moisture ceasing to be further dispersed, the Coagulation may be for a time suspended, and upon that account, upon the second Crystallization, may yield Crystals less regular, and apt to convene uniformly with the others, than in Artificial concretions performed in distinct Vessels. And on this occasion I shall add, That I have had Fire-stones brought from several Places, in one of which, the internal Texture was very different from the more Central Texture; and in another, I not only observed one Spherical Stone contained within another, but of a different Texture, and distinguished by a visible Commissure, tho' the Commissure was not so uniform as to admit these two to be separated. But perhaps it may be objected against what we have delivered, That these Bodies are found where petrifying Springs are not. Against which it may be offered, not to urge that Men and Beasts have been petrified upon the sudden invasion of a petrifying Spirit, that Rain-Water may bring such Particles along with it. Since over a Bath in Hungary, that abounded with petrifying Particles, the Steams which were arrested by the building over it, were turned into stony Concretes; which may give us Reason to think, that petrifying Vapours raised from the lower Parts of the Earth, meeting with rightly disposed Matter, may form Stones, without the help of Rain or Springs; which Conjecture may be favoured, by relating, that I have not only found an Earthy and Sulphureous Sediment in the bottom of Rain-water, but I have observed that a distilled Liquor being kept some time in a Vial well stopped, the Steams penetrated the Cork, and form whitish Stiriae, very slender and of a surprising length. And that petrescent Springs are not always requisite, will appear, since I have found transparent Stones in a dry Soil, which lay upon a Rock; and I have found that a solution of stony Stiriae in Spirit of Verdigrease, being poured upon Bolus Armenus, contained in a Glass, when the superfluous moisture was exhaled, several transparent and untinged Crystals appeared, dispersed through that Red Earth. And the best petrified Wood that I know of, was taken up out of a Plot of sandy Ground, where there was not the least signs of a petrifying Spring. And tho' some Stones seem to grow as from a Root, yet these may easily be supposed to have been form in certain Moulds; and that after their formation, the Winds or Rains washed away the loser Soil from their upper Parts. Besides it might be easily shown, that stony Concretions might be produced by the mechanical action of the Air upon the stony Parts, that successively apply themselves to the Matter that first gins to coagulate; and began to be forsaken by that moisture that accompanied those Parts, and was necessary to their due Application to their casual Roots; in imitation of which I have obtained from saline and stony solutions, dry Turfs prettily sigured, and diaphanous or White; as also slender Stiriae that seemed to grow out of the solid Glass. But further, sometime petrifying Particles may be so diluted with ordinary Water, as not to discover themselves till they have fit Bodies to work upon: For I have received transparent and petrified Cristals from a Lake in the North of Ireland, which grew to the Rocks in the bottom, but had no ill effects on the Fish which swum in that Water; and it is easy to suppose, that whether Water which lies in the Cavities of Rocks be impregnated with petrifick Particles from Springs, Rain-water, or subterraneal steams; I say it is easy to conceive, how these, after an Exhalation of the superfluous moisture, may petrify the adjacent Soil, and form different Stones, according to the particular Nature of the petrescent Liquors, and the disposition and structure of the Soil they invade; in which Soil if any Heterogeneous Matter be lodged whether Vegetable, Animal, or Mineral Substances, they must needs be found in that petrified Soil when broken up: Nor is it requisite that this Soil should be all petrified at once; for it may be petrified gradually, as the Position or porousness of the Body give advantage to the petrifying Body that works upon them; so that from hence it appears, how medicinal Stones of different Colours, Consistencies and Effects, may be form, and seem entire Bodies. And I have a Stone by me which contains a perfectly shaped Serpent coiled up in it, but without a Head; which appears to have been form before the Stone, in as much as in the upper and lower Parts of the Stone, there are Cavities left, which together form one Cavity, of the size and shape of the contained Body; and that the Serpent and the Stone about it, were petrified at several times, may be argued from the different Texture of the petrified Animal, it being a clearer kind of Stone than that of the Mould; and even that Part of the Mould itself which is contiguous to the included Body is whitish, and abounds with shining grains or flakes, in both which respects it differs from the other Parts. But to proceed, in those several places in which Stones are plentifully found, in times past pretrescent Liquors may have been, since not only Earthquakes, Inundations, sinking of Grounds, but the encroaching of the Land on the Water, as well as fiery Eruptions, have been able to dry up Pools and Lakes, and to divert the course of Springs and Rivers, so as to leave not the least footsteps where they flowed before. Another Argument which will favour: the Hypothesis already laid down, may be deduced from this, that by proper Menstruums Mineral Parts may be drawn from some of these Stones, so a Solution of Bloodstone turned an Infusion or Galls blackish, and so did a Loadstone Emeri and Marchasites opened with corrosive Menstruums. And Lapis Calaminaris kept in Fusion with Copper, changes it yellow for a Golden colour, and makes it Brass; and adds to its specific Gravity considerably. And Quicksilver is known to be distilled from Ore found in the Mines of Friuli. But as we before intimated, there are several Stones, which own their Virtues to a Mixture of Bodies specifically lighter than Crystal; which is evident, since not only Brimstone, but Bitumen, are specifically lighter, the proportion of Brimstone being as two to one, and that of Asphaltum as one and a little less than 4/10 to 1. And even some Bodies specifically Lighter than Crystal, may owe their Virtues to Mineral Particles, since they may be mixed with Ingredients specifically Lighter than Crystal, which may compensate the Surplusage of theirs; for I have had a piece of blackish East-Indian Flint, and likewise an English one of the same colour, the one of which weighed as 2 6/10 to 1, and the other as 2 7/10 to 1, which is equal to the specific Gravity of Crystal; so that the Blackish colour seemed to proceed from some Mineral smoke that had pervaded it, which may give us Reason to believe, that the matter of Medicinal Stones may be tinged with Mineral Vapours before it is hardened: And that several subterraneal Bodies may be raised in the form of Vapours, will appear from what hath elsewhere been delivered; and that Quicksilver will, we are assured by the effects of Fumigations in the Lues Venerea; and that it may be incorporated with Stones, may be observed in some kinds of native Cinnabar. And I have found that not only artificial but natural Salarmoniack, may be raised in the form of Exhalations by the help of fire. And that Salarmoniack, Sulphur and Mercury, may be sublimed into a Gold like substance, appears from the Preparations of Aurum Musicum, and that the Earth abounds with Mineral Exhalations of various kinds, appears from what hath been elsewhere delivered; as well by us as several other Authors; and since the Earth abounds with so great a Number of Minerals, there is no question but some of them may be able to penetrate and tinge some indurated Stones; and that a small quantity of a Mineral may be sufficient to tinge a great quantity of a Stony substance, will appear from several Experiments already delivered. But to proceed to the last Argument to be alleged on this occasion, I shall add, that it appears that opacous Gems receive their Virtues from Mineral Particles, since most of them consist of Mineral Bodies petrified. And tho' most of these Bodies differ little from artificial ones, we are not therefore to deny them Medicinal Virtues, since several Medicinal and specific Virtues are attributed to Chemical Preparations, and that artificial Bodies may be endued with Medicinal Virtues, appears from Galen, who delivers the ashes of a Crayfish as an Antidote against the biting of a mad Dog: And even Treacle is esteemed not only as an Alexipharmick, but endued with specific Virtues, upon the account of its manifest as well as occult Qualities. And to what I have said, I shall add, that several Stones of the same kind differ in the goodness of their Medicinal Qualities, as Lapis Nephriticus; and several of them have Virtues which seem to belong to other kinds, when they are impregnated with the like Exhalations; so that I have seen a Bloodstone which would stop Hemorrhagies when made use of without the Persons knowledge, yet by its colour it seemed to be of another kind of Stone. But to the foregoing Particulars I shall add, that subterraneal Exhalations may be so powerful and penetrating, as to petrify both Animal and Vegetable Substances, as appears from petrifyed Skulls, Bones, and pieces of Wood; and that Vegetable substances may be hardened into Stones is evident, since Lapis Lyncurius, a Stone near Naples, being rubbed and moistened, and then exposed to the Sun in a due season, will yield Mushrooms fit to be eaten, so that the seminal Principles of Vegetables may be petrifyed, without losing a power of exerting themselves when they find an opportunity: And these kind of Stones are sometimes found to be of an extraordinary bigness. And that other Earth's, subject to be petrifyed, may be endued with Medicinal Virtues appears, since I knew a Clay-Pit in which a Bed of Clay yielded by distillation a Volatile and strong Salt, which was a good Cordial, and a great opening and Diaphoretic Medicine. And that sublimable Salts, Sulphurs and Bitumens', may be met with in the Bowels of the Earth and in the Bodies of Stones, I have found by their Chemical Examen. And that Metalline Parts may concur to the Composition of a Medicinal Stone, may appear from native Sulphur, (which is itself a compound Body) besides a good proportion of Mineral Earth. CHAP. III. Of the Atmospheres of Consistent Solids. Of the Atmospheres of consistent Bodies. THAT fluid Bodies, such as Water, Wine, Urine, etc. emit Effluvia, is too evident to want proof; and that even consistent and solid Bodies emit Effluvia, will appear from what follows, since not only Leaves of Plants, but Ambergrease, etc. are manifestly odoriferous. And not only Volatile Salts are sensibly diminished, by being exposed to the Air, but Camphire which is a tough tenacious Body. And even from the Electrical Qualities of Amber, hard Wax, etc. it appears that they emit corporeal Effluvia; which sensibly affect the Nostrils when violently rubbed. And as further instances of the Effluvia of consistent Bodies, we may add, that not only Apples but Eggs lose of their weight in Winter, and so does Wood; for having caused a Cup to be made of it, and Counterpoised it, it grew sensibly and gradually lighter, so that tho' it wanted two drachms of two ounces, yet it lost forty grains of that weight in ten hours. And even Ice which weighed two ounces in a frosty Night, lost ten grains of its former weight, tho' not in the least thawed. And it is known to those that deal amongst Lead and Tin, that those Bodies emit very hurtful Effluvia, and Cold-share Iron hath been observed to smell so rank whilst red hot, that the Smith could scarce endure to work it; and not only Iron, but Brass and Copper, when heated smell very unpleasantly. And to these instances I shall add, that besides Loadstones, black Marble, as well as other Stones, whilst a Polishing, will emit sensible Effluvia, which is evident by the smells they emit. And amongst other Bodies which convince us, that they emit sensible Effluvia by their smell, I shall enumerate those Conical Stones called Thunder-Stones, which upon attrition emit a Sulphureous smell; and so did a Substance which much resembled a Marchasite: And I made a Mixture of a Metalline Body and a coagulated Mercury, which had considerable effects on the Eyes as well as other Parts, near which it was worn as an Appensum. And Vitrum Saturni, made with a good quantity of Minium, is not devoid of Electricity; nor is Brass free from an offensive smell, when its Parts are put into a violent concussion by turning. And amongst Electrical Bodies I have seen some of so close a Texture, and so hard, that they would strike fire, and Aqua Fortis itself would not work upon them, as Cornelians, Rock-Crystal, etc. And even so hard Bodies as Diamonds are found to be Electrical. And I have observed, that Concretions called Cugoli, made use of by Glassmen in the East-Indies emits a smell upon attrition; and so will a Calculus Humanus; and Iron itself if held to a grinding Stone without the use of Water. And Marchasites likewise upon an attrition emit a Sulphureous Odour. And even so fixed Bodies, as Regulus of Antimony, and its Glass, communicate to Liquors Emetic and Purgative Emanations; and Glass itself, which is fixed enough to endure the force of the Fire, upon Attrition, emits offensive Effluvia. And the Heat of the Sun and Fire have so great a stroke in exciting the Atmospheres of Bodies exposed to them; that Amber being exposed to the former, and Glass to the latter, they both became Electrical. And I question not, but that if a great many Bodies, not yet tried, were carefully weighed, they would appear sensibly to emit Effluvia; tho' the waste made by some Bodies is so small, as to be scarce discernible, if at all, as in Lodestones, Ambergrease, etc. Those requiring a long time to make their Consumption discernible, in which time we are not sure but the Weights themselves may have lost of their weight, as well as the Counterpoise, and consequently not be able to discover the loss those sustain. But there are several other, besides statical, ways of trying whether Bodies emit Effluvia or not; and there are several peculiar ways requisite to cause them to emit them; as Glass, etc. affect the Nostrils upon an Attrition. I had a Diamond, as well as a Ruby, which would be excited by a gentle heat in my Pocket, or only by strokeing my Finger over the former, tho' sometimes they would fail to be so easily or uniformly excited; and it is not a little strange, that upon the Tread of a Hare or Partridge, Effluvia should be so long emitted, as to give a Scent to Dogs several Hours after. And if Loadstones and other Bodies may have Constant Atmospheres which are only to be discovered by particular Bodies; several other Substances, not yet taken notice of, may emit Effluvia, which by peculiar Methods may be discovered. CHAP. IU. Of the Strange Subtlety of Effluviums. Of the subtlety of Effluviums. THE subtlety of the Effluviums will be most aptly represented, by considering, I. The strange extensibility of some Bodies, whilst their Parts remain tangible. II. The Multitude of visible Corpuscles, that may be afforded by a small Portion of Matter. III. The smallness of the Pores, at which the Effluvia of some Bodies will get in. iv The small Decrement of Bulk or Weight that a Body may suffer, by parting with great store of Effluvia And, V The great quantity of Space that may be filled, as to Sense, by a small quantity of Matter, when rarified or dispersed. And First, I have observed that a Grain of Silver Wire amounted to 27 Foot, or 324 Inches; and since half an English Inch may be divided into a 100 Parts by diagonal Lines, it must consist of 64800 true Metalline Parts, which may be well conceived to be made of Parts yet more minute. And I had a gilt Wire, an Ounce of which made a Wire 1000 paces long, allowing Five Foot to a Pace, and 720 Foot above; and had this Wire been drawn out to an equal smallness with the Silver Wire, the Gold would have been divided to an indefinite number of Parts, being sufficient to cover the superficial Area of so long a Wire. And I have known Silk to be drawn out of the Mouth of a Worm, which, tho' it weighed but two Grains and a half, was 300 Yards long. But to evince the great extensibility of Matter, we took six beaten Leaves of Gold, the sides of whose Squares were 3 Inches and 2/8, which Number being reduced to a Decimal Fraction, viz. 3125/100, and multiplied by itself, affords 10●5●/10000 for the Area of each, and this multiplied by 6, the Number of the Leaves amounts to 6313750/10000 square Inches for the Area of the six Leaves of Gold; which weighed but 1 Gr. ¼; so that 4 Grains was extended to above 50 square Inches. And if each of these Inches may, by Lines drawn from opposite Points, be divided each into 100 Parts, one Grain of Gold must be divided into 500000 little squares, discernible by a good Eye; and if an Inch were divided into 200 Parts, as I have one by me that is, than a Grain may be divided into 2000000 of squares. And to be satisfied further of the extensibility of Gold, I enquired, and was told that 8 Grains of Gold would gild an Ounce of Silver Wire as fine as a Hair, and which would reach betwixt 90 and 100 Miles. But supposing the Wire to be as fine as that first mentioned, and that 8 Grains of Gold went to gild it; a sheath of Gold weighing but 8 Grains, may be extended so as to reach 60 times as much (in weight) of Silver Wire as it covers; and consequently, a grain of that Wire being twenty seven foot long, the ounce of Gold would reach to 777600 foot i e. 155 ½ miles; and if this Gold Wire were cut into as small thongs or lists as posibly it might be, it must reach to a stupendious length. But secondly, to show into what a number of visible Corpuscles a Body may be divided, we put an ounce of Water into an Aeolipile, and having placed it upon a Chafing-dish of Coals, we observed that Vapours streamed out or above sixteen minutes; and considering a few intermitting gusts afterwards, and what drops of Water were condensed in the top of it, I guessed, that had the whole been driven out in Vapours they would have continued twenty minutes; N. B. to the Orifice of the Aeolipile we applied a long Tube twenty Inches long and an Inch in Diameter, the remoter end being continued about six Inches longer, and so far expanded that its Diameter was four or five Inches; and by the help this Pipe we were able tho' not actly to measure the Extension of the rarified Vapours. To this instance I might add the prodigious expansion of some Inflammable Bodies, when turned into actual flame, as Spirit of Wine, etc. Which being burnt in a Glass Lamp, so contrived that the Surface of the Liquor was still Circular, the waste made in ¼ of an hour was very small, tho' the Physical superficies of the Liquor must needs be successively rarified and expanded, and fly away in streams; and if so little of this Liquor was able to afford matter for flame so long, the same bulk of a more compact Body may easily be supposed to be capable of being expanded to much greater Dimensions. And to these instances I shall add, that half a grain of Gunpowder being exploded under a Vessel, whose Basis was eight Inches and its Altitude twenty; and its figure such, that it was more Capacious than a Cone of that size, the exploded Gunpowder was observed to fill the whole Cavity of the Vessel as to sense, and successively issued out of the upper Orifice for half a quarter of an hour, so that the Diameter of it being two Inches, many Myriads of visible Corpuscles, must be conceived to throng out in so long a time as they crowded out one after another: But to make a kind of an estimate of the Expansion of this Substance, we filled the Vessel full of Water, and found that the weight of it amounted to 320000 half grains: And if we suppose the specific Gravity of the Gunpowder to be as much again as that of Water, we my probably guests the smoke to possess 500000 times the space that the Gunpowder did. And as a further Argument of the great minuteness of small Parts of matter, I shall urge the smallness of Cheese-mites; which being so small as not to be discernible to a naked Eye, but when they move, must be made of extremely fine Parts, otherwise there would not be room enough for an Organical Body; and if an Organical Body furnished with all the Parts requisite for the Preservation of Life be contained in so small a compass, how minute must they be at the first, since the Eggs out of which they are form bear but a small proportion to them, when perfectly form, and even comparative Observations tell us, that a Mite being ten days a hatching, the Rudiments of its Body at the first must bear but a small proportion to the bulk of that small Egg; and to this I shall add, that tho' these Creatures be so very small, yet I have been able to discern single hairs growing upon their Legs. Another instance of the Extension of matter minutely divided is this, viz. We dissolved a grain of filings of Copper in Spirit of Salarmoniack; pouring the Solution into a tall Cylinder four Inches in Diameter, and successively filling it four times with distilled Water, still pouring it off into a Conical Glass; which being done, and the weight of the Glass Cylinder deducted from the Joint weight of the Liquor contained in it, we found that one grain of Copper was able to give à Tincture to 28534 times its weight of Water, tho' its specific Gravity is not half so much as that of fine Gold: and if we estimate the proportion not by weight but the bulk of these Bodies, the bulk of Water to Copper being as nine to one, the aforementioned number multiplied by nine will give us the proportion betwixt the tinged and ting the Body, so that one grain of Copper gives a colour to 256806 parts of Limpid Water, and by prosecuting this Experiment further, I found that it was able to give a manifest Tincture to above 385200, and a faint but discernible one to above 513620 times its bulk of Water. To show that the Effluvia of Bodies may enter in at very small Pores, I shall intimate the effects of Cantharideses held in the hands of some Persons; and on the Neck of my own Bladder when applied outwardly to my Neck. And not only Scaliger tells us of Spiders in Gascony, whose Virulent Poison would penetrate the Shoes of those that trod upon them, but Piso speaking of a Fish called Amoreatim, and by the Portugal's Peise sola, he says, Quae mira sane Efficacia non solum Manum vel levissimo attactu, sed & pedem, licet optime calceatum, Piscatoris incaute Pisciculum conterentis, Paralysi & stupore afficit, instar Torpedinis Europeae, sed Minus durabili, Lib. 5. Cap. 14. And to show that some Emanations, even of solid Bodies, may be subtle enough to get through the Pores even of the closest Bodies; I shall add, that a needle being Hermetically sealed up in a Glass Tube, and that laid upon Water, a Loadstone would cause the Needle to leap up in it, and by the help of the Loadstone, I could lead the Tube from one part of the Surface of the Water to another, as I moved the Loadstone. And to show that the Magnetical Effluvia of the Earth, may penetrate so close and compact a Body as Glass, I shall add, that a Cylindrical piece of Iron being sealed up in a Glass Cylinder, and held in a Perpendicular Posture, it acquired such Magnetical Virtues, as to become a North Pole, and according to Magnetical Laws to drive away the North Point of a Needle; but being inverted, and held under the Point of a Needle, it became a South Pole, and attracted it. Another Proof of the great subtlety of Effluviums, may be taken from the small decrease of Weight, by parting with store of such Emanations; as Vitrum Antimonii, Crocus Metallorum, and Quicksilver, the two first of which give a Vomitive Virtue to a vast quantity of Wine, without growing sensibly lighter, and so Quicksilver impregnates Water with a Virtue of kill Worms. And a piece of Ambergrease which weighed about 100 or 120 Grains, being suspended three days in the open Air, lost not sensibly of its Weight, notwithstanding the quantity of odoriferous Steams it must have parted with in that time. Assa Foetida, in about six Days, lost about half a quarter of a Grain; one Ounce of Nutmegs, in six Days, lost 5 Grains ½; and an Ounce of Cloves, 7 grains ⅝. And tho' Lodestones emit Effluvia without a sensible loss of weight, yet I suspect, that as these Magnetical Particles fly out of one Pole, they enter in at the other, and so make the Pores of the Loadstone their constant Thorow-fares. To these Instances I shall add, that a Grain of Copper being dissolved in a spoonful of a Menstruum, and that put into a Glass-Lamp, the Metal tinged the Flame, which continued half an Hour and six Minutes; so that supposing the Flame to have streamed through a Cylindrical Pipe so long, that small parcel of Metal must be divided into a vast Number of small Parts; for Water, which ran through a Cylinder, whose Diameter was but half as great as that of the Flame, amounted to above Nine Gallons, or Seventy two Pounds. The last Particular I shall insist upon, to show the strauge subtlety of Effluviums, is the great quantity of space a small parcel of Matter may be extended to, and as to Sense possess it; this we may be enabled to guests at, by considering how long a Dog will distinguish the Scent of Partridges, Hares, etc. after they have left the Place, and will almost give one sufficient grounds to guests how long the Animal hath been gone from thence before. And I am told that a Bloodhound will not only perceive the Seent of a Man that hath gone over a piece of Ground several Hours before, but that the scent of a Deer will continue upon the Ground from one Day to the next. And if we consider that the eighth part of a Grain, can scarce be supposed to be left on the Ground where such an Animal hath stood, and likewise at what distance it may be scented, and how long that scent continues, it will be sufficient to convince us of the extraordinary minuteness of those Parts of Animals, which were rendered more apt to be dissipated in Effluviums, by their having been first strained through the Pores of their Bodies. Nor is it less remarkable, that Birds, especially Crows, are able to discover the smell of Gunpowder at a considerable distance; and that they are, I am satisfied by my own Observations, as well as the Relations of others. And on this occasion I shall add, That Julius Palmarius, in his Tract de Morbis Contagiosis, observes, that Horses, Beefs, Sheep, and other Animals, have grown mad by eating the Straw that mad Swine have lain on; which may give us Reason to suspect, that the Feet of distempered Animals may leave an Infection upon the Grass they tread on. But to prosecute the chief aim of our Discourse, I shall add, That since Corpuscles that are too minnte to be visible, may affect an Organ of Sense; it is not improbable, but that there may be a great many which may be so fine as not to affect any one of our Senses, and consequently may continue an Atmosphere much longer than we are able to take notice of. So Forestus tells us of a Pestilential Contagion that was a long time preserved in a Cobweb. And Alexander Benedictus tells us of a Flock-Bed, which, when several Years after the Plague, it was beaten, it presently infected the Bystanders. And Sennertus tells us that in Vratislavia, in six Months, six Thousand Men died of the Plague; and that from that time, the Infection was preserved in a Linen Cloth, and being displayed in another Place, 13 Years after, it infected that Place likewise. And Trincavella tells us, that an Infection was preserved a long time in Ropes, by which dead Persons were let down into their Graves. And an Instance of the like kind we are furnished with by Diemerbroeck, who acquaints us that an Apothecary of his, turning over some Straw, upon which a Bed had lain which held an infected Person, the Steams immediately caused Blisters upon his Legs, and a Carbuncle which was a Fortnight in healing. And to conclude this Chapter, I shall add, that I have a pair of Spanish perfumed Gloves, which have continued their scent about Thirty Years, tho' they were not so much as shut up in a Box. CHAP. V Of the great Efficacy of Effluviums. THO' Particles of Matter which are minute, are looked upon to be unable to have any considerable Effects; O the great Efficacy of Effluviums yet I shall endeavour to show, that they may have considerable Effects. I. Upon the account of their great Number. II. Their Penetrating Nature. III. The Celerity and Modification of their Motions. iv The congruity of their Bulk and Shapes to the Pores of the Body they are to act upon. V The Motion of one Part of a Body which they cause to act upon the other. iv Their Aptitude to cause themselves to be assisted by more Catholic Agents; tho' they may perform several things considerable upon these Accounts; yet sometimes two or three, or more, concur to the producing of the same effect. And, First, From what hath been delivered in the foregoing Chapter, it appears that the Effluvia of Bodies are very minute, and consequently it will follow, they must be numerous, and that a great number of small Agents, when they act per Modum unius, may have considerable Effects, is evident; since inundations of whole Country▪ may be caused by Showers of Rain when drops fall in multitudes; and aggregates of small Sands, not only bound the Seas, but form Banks, upon which the greatest Ships are sometimes split; and tho' the Effects of a single Grain of Gunpowder is immaterial, yet prodigious things may be done by a great number of them; and tho' Vapours are made up of very small Particles, which seem to be inactive, yet in moist Wether, they cause Salts to melt, wood to swell, and Viol-strings, if they be stretched too much, to break. And it hath been observed, that the invisible Steams of a newly whited Room are so offensive, that People who slept in such Places, have been found dead in the Morning, being suffocated with those Fumes; and tho' the Vapours which can issue out of such Bodies at once, cannot be sufficient to produce such Effects, yet if we consider that they continually succeed each other, as Wind out of an Aeolipile; their Number and Minuteness may enable them to cause considerable Effects. And that the subtlety and penetrating Nature of Effluvia, contribute much to their Effects; appears, since good Aquafortis and Spirit of Nitre are so penetrating, as in a little time to pervade the Corks with which the Bottle they are contained in are stopped, and to reduce them to a Pap. And running Mercury hath been found in the Heads of those that have been too much exposed to Mercureal Fumes. And in the Laboratories of Chemists, the Steams of Sulphur, Antimony, Arsenic, etc. make those stagger that less cautiously unlute the Vessels in which they have been sublimed or distilled. To which Instances may be added, the infectious Steams in the Plague which suddenly infect the internal Parts; and likewise the sudden. Effects of a Torpedo. And I prepared a Sal-Armoniac so powerful, that it restored a faculty of Smelling to one that had lost it a considerable time; which Virtues it had, besides those more common ones, of affecting the Eyes, Mouth and Stomach. And on this occasion, I shall subjoin, that the Steams of Water assisted by warmth, are sufficient to dissolve hard and solid Bodies, so that by Philosophical Calcination, solid pieces of Hartshorn are made so friable, as to be easily reduced to Powder, only by being hung over the Steams of distilled Waters: And to this I shall add, that under several Places in the Torrid Zone, the Dew is so penetrating, that it causes Knives to rust in their Sheaths, and Swords in their Scabbards, and even Watches in their Cases: And in England I have known hard Bodies become friable by the insinuation of Vapours into their Pores; and I have known solid and Mineral Bodies burst, by the powerful insinuation of Effluviums. And that the Celerity of the Motion of minute Bodies, may contribute much to their Effects, appears from the Effects of Gunpowder, Aurum Fulminans, Flames, Whirlwinds, and Winds. And I have made it appear, that those Odoriferous Steams which swim in the Air, and affect our Nostrils, are in too languid a Motion, till enabled to affect the Sensory more powerfully, by running through the Nostrils in a Stream; and I have likewise made it appear, that Setting-Dogs, etc. will be much more affected with a Scent, when the Wind Blows from the scent towards their Nostrils, than when it comes the contrary Way, the current of the Wind causing the Odoriferous Steams to affect the Sensory more briskly. And Electrical Bodies exert that Faculty more strongly after Attrition, the emission of their Electrical Steams being by that means excited: And the Learned Faber hath observed, that if a Hare was suspended near an Electrick when the Effluviums were too briskly agitated, it would not be attracted, but driven away from it. And I know a certain substance made by distillation, whose smell in the Cold is very inoffensive, but when it is warm, it emits Steams more strong and penetrating than Sal Armoniac. And I have known solid Substances stink egregiously when excited to emit their Effluvia by Attrition. And as celerity of motion contributes to the Effects of subtle Bodies, so does the different modification of that Motion; for as a Stick or a Javelin, hath different Effects when they fly with one end first, from what they have when they twirled round with a certain Rotation; and the sounds of Musical Instruments are different, according to the different determination of their Motion, And the Impressions made upon the ambient Air. And that, besides what we have already taken notice of, the congruity or incongruity of the Particles of Matter, in reference to the Bodies they are to work upon, contribute much to their Effects, appears from the Effects of Lightning: For I have seen two tall drinking Glasses so altered in their shape by the influence of Lightning, that the one was a little widened near the bottom, and the other so far bend, that it stood awry; the Beams of Lightning being able, in the twinkling of an Eye, to melt Glass; tho' in Glass Furnaces the Fire is sometime before it can produce that Effect. And I once saw Led melted by Lightning, which left the Glass unaffected; and likewise other combustible stuff that was near it; and tho' it left these Things untouched, yet it threw down part of a Wall, belonging to the House, by passing through it. And it is a common Observation, that Thunder, either by giving a determinate Concussion to the Air, or transmitting some Effluvia, turns Beer sour; but having sealed some up in Glasses Hermetically, the Thunder was not able to affect the Liquor contained in them; and it is a common practice to prevent Beer from souring upon Storms of Thunder, to place Chafing-Dishes of Coals under the Barrels, the sulphureous steams, being by that means so altered, as either not to be able to penetrate the Barrel, or not able to alter the Liquor. Another Way, by which considerable Effects are caused by Effluvia, is by exciting such a Motion in the Body they work upon, as to make one part of it act upon another. Instances of which may be brought from inanimate Bodies, as well as living ones, since some vigorous Lodestones destroy the attractive Virtues of an Excited Needle in a trice; or give it a Virticity quite contrary to the former, without touching it; and these magnetical Emissions which must needs be very minute, since they are subtle enough to penetrate Glass, are able to take up a considerable weight of Iron; so that I have seen a light one which would take up Eighty times its weight. But the chief Instances I shall now insist on, are those wrought upon Animals; for it is evident, that our Organs of smelling are chief affected by such minute Particles of Matter as the finest Odours consist of; nor do they always affect us as Odours, since violent smells, whether stinking or sweet, are able to cause very troublesome head-aches. And the smell of a very pleasing Perfume may produce in a humane Body, which before was well and strong, both faintness, swoons, loss of sensible Respiration, Intumescence of the Abdomen, seeming Epilepsies, Convulsive motions of the Limbs, etc. And I had a Salarmoniack which would in a little time remove Hysterick fits, and recover People, who by the bystanders were judged to fall down in Epileptical fits, which sudden effects seem to depend on the consent of the Genus Nervosum. But, besides these effects of Odorous Bodies upon Women, I know a Man of a strong Body and a sanguine Constitution, who will be put into a violent Headache by the smell of Musk; and another to whom the smell of Roses was as offensive; and I know a Lady, who would presently swoon at the smell of Roses, if they were not speedily removed. And as these slight smells have proved offensive, so it is not much less considerable that the smell of Salarmoniack cures the Headache. Besides, the aforementioned effects of Effluvia, it is observed, that Women have miscarried upon the stink of a Candle carelessly extinguished. And I not only know a Gentleman who will Vomit upon the smell of Coffee, but a Physician who will Vomit and Purge, if he does but smell at Electuarium Lenitivum: And I know another whom the smell of the grease which is about the wheels of a Hackney-Coach will make sick, and cause to Vomit, if it does but pass by him. And not only smoke is offensive to the Eyes and Lungs; but the invisible steams of Salarmoniack. And besides, the aforementioned instances of the effects of Effluvia upon the Genus Nervosum, I shall add one of their Effects on the humours; for I know an Apothecary who upon the smell of Roses, hath such a Colliquation of Humours in his Head, that they set him a coughing, make him run at the Nose, and give him a sore Throat, and also by an affluence of humours make his Eyes sore. And as Effluvia may be enabled to perform several things on the account of the structure of particular Bodies; so they may effect several things, by Virtue of the Fabric and Laws of the Universe, for Bodies by Effluvia may be rendered fit to be wrought on by Light Magnets, the Atmosphere, Gravity, or some other Catholic Agent of the Universe. And to what instances have already been given of Bodies working upon others placed at a distance, I might add the effects of contiguous Bodies, as Bloodstones, Cornelians, Nephritick Sons, Lapis Malacensis, and some Annulets, and other solid Substances externally applied by Physicians, as Cantharideses, etc. CHAP. VI Of the determinate Nature of Effluviums. Of the determinate Nature of Effluviums. THO' Aristotle and his followers, have only distinguished the Exhalations of this Globe into those which he calls fumes, and which rising from the Earth, he terms hot and dry; and those Vapours which rise from the Water, which he calls hot and moist, in these words, 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉; yet besides these slight differences, since the Earth contains several Bodies, which have each of them distinct Atmosphere, we may probably conceive them to have their distinct and determinate natures; and even in fluid Bodies Heterogeneous Parts may swim, which notwithstanding their fluidity may retain their determinate Nature, since Rock-Allom and Salt-Petre being dissolved together in Water, upon a gentle Evaporation, will each of them shoot into Crystals of their respective and determinate Natures. And that Effluvia retain their determinate natures, tho' so small as to swim in the Air or Water, appears, since upon their Reunion they are of the same Nature with the Body that emitted them; as Water raised in Vapours condenses again into drops of Water: And Quicksilver in Distillation, if it be raised with a convenient fire, will almost all be found in the Receiver, in the form of running Mercury: And if when Chemists are either making an Amalgama, or forcing the Mercury away from it by the fire; they hold a piece of Gold in their Mouths, it will be white as if it were Silvered over. And not only Sulphur, but Camphire sublimed in close Vessels, unites into a Substance of the same Nature as the other, and tho' a Body be compounded of a Metal and another Mineral, and two or three Salts; yet upon the Purification of the Mixture from its grosser Parts, if the remaining and finer Parts be minute enough and finely shaped, the wholly Liquor will ascend; and yet in the Receiver altogether recover its pristine form of a transparent fluid, composed of differing Saline and Mineral Parts, which is evident in the Distillation of Butter or Oil of Antimony very well rectified; for this Liquor will pass into the Receiver diaphanous and fluid, tho', besides the Particles of the sublimate, it abounds with Antimonial Particles, carried over and kept invisible by the corroding Salt: And I am told, that Tin will retain its own Nature in the form of fumes or flowers, which is evident, since that white sublimate which is gathered above the Furnaces where the Ore is brought to Fusion being melted down, will yield store of Tin. And besides these ways, the determinate natures of Effluviums, may be distinguished by their sensible Qualities, since the Exhalations which rise from several Bodies produced by Art, appear to be of different colours; tho' no external Heat is employed to raise them; for the fumes of Spirit of Nitre well rectified, when cold and stopped up, appear in the Vial to be of a reddish colour; and when the Vessel is unstopped they will ascend in the form of a reddish, or Orange tawny Smoke. And Spirit of Salt or Oil, will when exposed to the open Air, ascend in the form of a white Smoke; and so will a Volatile Tincture of Sulphur made with Quicklime; and both this and that of Salt-Petre do by their smell, as well as operation, discover of what Nature they are; and I have observed, that the essential Oil of Wormwood, being drawn off in a Copper Alembick Tinned, was not only green, but retained that colour when rectified in a Glass-Vessel; and tho' these essential Oils be but the condensed Effluvia of Vegetables, yet they retain the genuine taste of the Bodies from whence they were drawn. And not only Wormwood but Amber may communicate their taste, by Effluvia raised without the help of Heat; for Wormwood having been kept in a close Room, not only affected the Nostrils strongly, but the Tongue with a bitter taste, and Amber kept in Spirit of Wine impregnated it sufficiently to give it a genuine taste, as well as smell; and that most essential Oils retain their genuine Odours is very evident. And that the Effluvia of Bodies may affect even the Touch of Animals, may not only be argued from the effects perceived by some People upon changes of Wether, but by that memorable passage related by Diemerbroeck, who after he was cured of the Plague, it left such a change in some Parts of his Body, that he says, Ab illo periculo ad contagiosos mihi appropinquanti in emunctoriis successit dolour, vix fallax Pestis indicium. To which I shall add, that I knew one who could hear very soft whispers when ill of a Fever, tho' the sound and healthful standers by could not; and I was told by a Lady, that she could tell by her smell, whether one that came to visit her had been in any place where the Ground was covered with Snow. And I knew a Gentleman, whose Eyes were so tender during a Distemper he had in them, that he could discern and distinguish colours in the dark. And I am told, that a Bloodhound found out a Man barely by scent, tho' he had passed through a Market Town, and several Crowds of People. And further instances may be brought from Observations made on Bloodhounds, some of which will scent a Deer twenty four hours after. And a Gentleman told me, that he knew when his Dogs were in pursuit of a Fox or a Hare, because they ran with their Noses nearer the Ground after the latter, the scent of it not being so strong. And I prepared a Body of a Vegetable Substance, which, tho' actually cold, would impart its colour to a Metalline Plate; tho' separated from it by the interposition of a piece of Paper. But perhaps it may be Objected by some, that these Effluviums may be altered by uniting with each other in the Air. To which it may be answered, That they may nevertheless reserve their determinate natures, tho' they act conjointly or so near it, that their distinct Operations cannot be perceived; as when two strings of a Musical Instrument are struck at the same time, they both of them seem to make only one Impression upon the Ear. And if Spirit of Nitre be dropped into Oil of Tartar per deliquium, upon an Evaporation of the superfluous moisture, the Acid and Alkalious Particles will form Nitrous Concretions, whose taste will be different from that of either of the separate Ingredients: And so if an equal proportion of Salarmoniack, be added to a strong solution of Pot-ashes or Salt of Tartar, a subtle urinous Spirit will come over in Distillation; and also a Caput Mortuum, which is almost wholly a compounded Salt, differing enough from either of the Ingredients, especially the Alkalizate, in taste and other Qualities. And to these Instances I shall add, that several flowers being aptly mixed in a Nosegay, and held at a distance they make a confused and joint impression upon the Organ of smelling; and so do Perfume made up of several Ingredients; and Spirit of fermented Urine, and of Wine being well dephlegmed, will incorporate like Wine and Water, without affording the least dry Sediment; but if in a convenient Vessel, they be exposed to a moderate Heat, the ascending fumes will adhere to the upper part of the Glass, in the form of a white but tender Sublimate, different from either of the Liquors not only in consistence but taste and smell. And if Spirit of Salt and Nitre, be elevated by Distillation in the form of fumes, the condensed Liquor will dissolve Gold, tho' neither Spirit of Nitre nor of Salt would do so. And to demonstrate the Coalition of steams in the Air, I shall add, that having filled two Vials, the one with Spirit of Salt, and the other with Spirit of Salarmoniack well rectified, the ascending fumes which before were invisible, working one upon another in the Air, form visible steams, which appeared like Smoak, but when they were removed a greater distance from each other, the separate and invisible steams were no longer discernible. And one thing relating to this Experiment which was remarkable was, that a drop of Spirit of Salt hanging at the end of a Glass stick, being held over the Orifice of a Vial with a long Neck, the ascending Vapours of Salarmoniack would form a Smoke, which would be visible till it was a quarter of a yard above the Glass; but if the drop was held within the Neck of the Vial, the aforementioned fumes would fall into the Ball of the Glass, like a stream of Liquor, and spread itself like a mist upon the Surface of the Salarmoniack. Which Experiment may help us to account for the sudden Invasion of Meteors and Clouds, especially in reference to the coming in or ceasing of several Epidemical diseases; and more particularly the Plague, which seems to depend on the Occult temper, and alterations of the Air, differently impregnated with subterraneal Effluvia. An Instance of which is related by Diemerbroeck, who tells us of a Plague occasioned by washing of foul Linen with Soap, the Fumes of the Smoak uniting with other Effluvia in the Air, causing that Effect; to which might be added, what is observed about the ceasing of the Plague at Grand Cayro in Egypt, but enough of that having been already delivered in another Place; I shall add here, that I have made a stain upon a Body by the invisible steams and Effluvia of another cold Body; I altered the Colour of that Slain by the invisible and cold steams of a Third. And to countenance my Conjecture of the Cause of Meteors, besides what hath been said of subterraneal Effluvia in another Place, I shall add the following Citation from Agricola; who having mentioned, out of Ancient Historians, the raining of White and Red Liquors, subjoins. autem majorem fidem habeamus Analium monumentis facit res, res illa decantata, quae Patrium memoria in Suaevia accidit; Aer enim ille stillavit guttas, quae lineas vestes crucibus rubris, quasi sanguineis imbuebant. And it will not be thought strange that subterraneal Salts, Bitumen and Sulphurs, may be raised into the Air, if so fixed a Body as common Earth may, which the newly cited Author testifies. And that the odoriferous Particles of Plants reserve their determinate Nature much longer than we are wont to imagine, may appear; since one drop of Oil of Cinnamon, gave not only a taste to 14000 times its Bulk of Water, but withal, diffused a great number of odoriferous Particles through the ambient Air. The Last way we shall mention to evince the determinate Nature of Effluviums, is from their Effects on other Bodies. As the stupefying Effluvia of the Fish Amoreatim mentioned by Piso. The effects of Opium and Hypnoticks upon a Boy, who whilst he was distilling them, cast him into a sleep. And the Root and Juice of Mandragora is said to cast those that take it into a deep Sopor like a Lethargy; and Levinus Lemnius tells us, that the Apples of the same Plant being laid in his Study, made him so sleepy, that he could scarce recover himself: Aurelaeus tells us, that the Poison of a Mad Dog hath been conveyed to one in the form of Effluvia; and Calius Aurelianus acquaints us, That some have become mad by being wounded only by the Claws of a mad Dog; and that one fell into an Hydrophobia, solo odore ex rabido cane attracto. And Matthiolus tells us of one who was poisoned only by putting his Hand into the Mouth of the mad Dog, without being bit; and to this I shall add, that Sennertus relates, that a Painter having opened a Box, in which Realgar had been contained, the Fumes being snussed up his Nostrils, presently caused a giddiness in his Head, and fainting Fits. To these Instances I shall add, That several have been purged by the smell of Black Hellebore; and as Sennertus' witnesses by the Odour of Coloquintida; and there are several other Things which purge when only externally applied: And it is attested by approved Writers, that the Shadow of a Wallnut-Tree, with the Leaves on it, is very hurtful to the Head. And it is not only observed, That Birds will not so much as light upon those Poisonous Trees in the West Indies, called the Manchinello-Tree; and it is looked upon as safe for Men to eat of Fruit found in a strange Country, if it appears that the Birds have been pecking at them before. And Nicolaus Florentinus tells us of one, who drawing into his Nostrils the Smoke of a Spider, he was much disordered, and fell into a fainting Fit, and was much disordered about the Heart, his Pulse being likewise weak; tho' after he was cured by a mixture of Treacle, Diamosc. and the Powder of Zedoary. And I saw a Berry called Maccu-buy in Ireland, which being pounded in a Mortar, caused the Head and Face of one that stood hard by, to swell enormously. And, To what hath been delivered of the determinate Nature of Effluviums, I shall add, that Amber, Musk, Civet, etc. will communicate a Perfume to Gloves, though at a distance off them; and contagious Distempers, as the Plague, Smallpox, or Measles, may not only be communicated by immediate Contact, but by steams which issue from the Body of the sick Person. But to conclude this Chapter, I shall add the following Experiment, Viz. Having shut up an Ounce of a Volatile Tincture of Sulphur in a Vial, capable of holding at least twice as much, and having placed a Paper at some distance, and unstopped the Vial, the spreading Fumes presently caused what was writ with invisible Ink to become legible. And so would several Letters writ with a Solution of Sublimate in Water, some of them being more, and others less Black, according to their distances from the smoking Liquor and other Circumstances: And when the Paper thus writ upon, was held over the Orifice of the Vial, tho' the Letters were on the upper side, yet in a quarter of an Hour, they became legible; and as in some cases, this smoking Liquor, with a solution of Sublimate, will produce a Precipitate of a Silver Colour, so in some of the Colourless Ink we found the like Colour. And I have performed the like with a couple of Liquors, wherein was neither Sulphur nor Sal-Armoniac, nor Sublimate. And as a farther Proof of the great penetrancy of Effluviums, I shall add, that having a Paper which was writ on with this invisible Ink, betwixt six folds of Paper, these Fumes penetrated it in Ten Minutes, and turned the Ink Black; and another piece of the same Inked Paper, being placed betwixt the Leaves of a Book, the steams penetrated Twelve in three Minutes, and turned the Ink blackish. CHAP. VII. Of the Porousness of solid Bodies. Of the Porousness of Solids. THAT even solid Bodies are not destitute of Pores, I am inclined to believe, because most solid Bodies, as Gems, etc. have once been in fluid Forms; and since Fluids are generally made up of Particles of a determinate size and shape, they must needs leave some Pores betwixt them. Another Reason why I am inclined to think most Bodies porous, is their specific gravity; which would not vary were the Parts of them equally compressed and closed together, but since Copper is heavier than Iron and Gold, as nineteen to one to its proportion of Water, and Copper only as nine to one, it must follow, that the matter of Iron possesses as much space again as Gold and more. And tho' hardness is urged by some as an Argument of their Substance being condensed, yet I have elsewhere shown, that tho' Diamonds are the hardest Bodies, they are far from being the heaviest, which is the only sign whether they be condensed or not. And since Metals themselves are made up of a Coalition of several Parts, it is impossible they should be so Physically adapted, as totally implere spatium; since were Cubes made of Marble, it is impossible they should be so exactly Polished as every where to be contiguous, since the Bodies employed to Polish them are observed to make little furrows upon them, and consequently leave little Intervals or Pores. And that Wood is not void of Pores will appear, since Quicksilver hath been observed to penetrate the sides of a hollow Cylindrical piece of Wood, and when the Air was drawn out of my Pneumatical Instrument, the external pressed so hard upon the outside of a Board which covered it, that tho' it was of strong Wood, and of a considerable thickness, yet it made its way into the Cavity of the Receiver, through the Pores of the Wood; and to these Instances I shall add, that the fumes of a Smoking Liquor tinged a Copper Halfpenny, through a broad thin shaving of Deal, tho' we could not discover any sensible Perforation; and the same Experiment being again repeated with two, and a third with three shave, they tinged the Copper Halfpenny, tho' not in so little time, nor quite so conspicuously. And, That baked Clay is not void of Pores is evident, since Oil will soak through strong and well baked Earthen Vessels, and so will Solutions of Nitre and some other Salts; and very few except Hassian Crucibles will keep Salt of Tartar long in Fusion without being penetrated by them. And Vitriol and Salt-Petre have been observed to lose much of their weight when distilled in Earthen Vessels, the subtle and spirituous Parts flying away through their Pores. And I am told, that those Juggs that are made of Earth, hardened sufficiently to strike fire with a good Stell, have their Pores pervaded by the most subtle Parts of Spirituous Liquors; and it hath been found by Experience, that Spirituous Cider hath sweat through the sides of Stone Bottles; which manifested itself by its taste: And I have found, that Silver dissolved and turned into a horny Substance with Aqua Fortis, being kept in Fusion in an Hassian Crucible, several Particles penetrated the Pores of it, and appeared on the outside. And to prove that natural Stones are porous, I shall intimate, that I had a Vessel made of Stone sent from the West-Indies, through whose Pores Water would sweat; and if the Transparency or Opacity of Bodies proceeds from a rectitude or crookedness of Pores, which makes them fit or unfit to transmit the Rays of Light, Oculus Mundi will be an Argument of the Porosity of Stones; since whilst it is dry and in the Air it is opacous, but when it hath lain a while in the Water it becomes transparent like Amber, but soon loses its Diaphaneity when exposed to the Air again, and so Paper wet with Water becomes more transparent, but loses of that Transparency when dried again; and to favour this explication, I shall add, that an Oculus Mundi having been weighed after it was taken out of the Water, it appeared to be heavier than before. And since several Stones, as Granates, Emeri, etc. contain Mineaal Parts, it is impossible they should be exactly contiguous without leaving some Pores betwixt them and the Parts of the Stone; and for the like Reason all artificial Gems made by Fusion, and tinged with Heterogeneous Pigments must be supposed to be furnished with Pores; and since natural Gems are made up of Stony Ingredients, and Mineral Parts, for the same Reason we must suppose them to be furnished with Pores likewise; and the like may be concluded in reference to all Heterogeneous and compound Substances; as Marcasites, Loadstones, etc. And that white Marble is not void of pores may be argued not only from its easy Solution by Aqua Fortis, Spirit of Salt, etc. but from its aptness to be tinged with Vapours, that are not fretting, so that red and other colours may be soaked into it as Oil is into Wood And having cemented some clear Fragments of native Crystal with a composition of some Volatile Minerals, together with a Salt or two, and having suffered the Crucibles to cool leisurely, several of the Fragments were stained here and there with different colours, some more and others less dull; but whether the Tincture these pieces of Crystal received proceeded from some of the finest of the Mineral Parts, imbibed into the Stone when flawed with too much haste; and whether upon cooling those flaws did not grow too close to be discernible to the Eye, I shall not determine, but shall add, that it hath been observed, that Rubies when Polished upon the Wheel, and very hot, have seemed full of cracks, which upon their cooling wholly disappeared. And that Metals themselves are porous may be argued, from their aptness to be dissolved in proper Menstruums. And especially by laying Sulphur and thin Plates of Copper SSS, in a Crucible upon which another was luted, to keep the Sulphur from taking fire; for having kept them thus about three hours in a heat, which was sufficient to melt the Sulphur, but not the Metal, when it was taken away from the fire and cooled, we found, that the Sulphur had so penetrated the Body of the Copper as to turn most of it into a brittle Substance, which would crumble away with ones fingers, being altered not only in Texture but colour, some being of a dirty dark colour, others of a violet, and many of the Plates when they were broken, seemed to have been divided into two Plates, and to have a manifest distance betwixt them, and we could likewise discern the fibers of the Metal, extend themselves from one side of the Copper Plates to the other. And that the Sulphur penetrated into the Pores of the Copper-Plates might not only be discerned by their increase of weight, and bulk, but a Blue Flame which would discover itself when they were laid upon quick Coals. And by a like Experiment, we found that the Body of Silver, Tin, and Led, might be penetrated. And not only Sulphur, but Arsenic will penetrate thus into the Body of Metals. And I know a Pigment which tinged the Body of Copper, so as to give it the Colour of Gold: And Perfumes do not only continue long in the Pores of Glasses; but I am told by one, that he had a Watch, whose Metalline Case was richly perfumed. And I remember I made a Substance much like Gold, which retained several Mercurial Particles in it, and being cast into a Ring, it was observed to have manifest Effects on the Eyes of several Persons. And I am told that the Offspring of the Granadine Moors, had an Art of curiously perfuming the Weapons they forged; and the same Nobleman who told me this, acquainted me that he had a Fowling-piece whose Barrel was perfumed, but its smell was much fainter after it had been scoured. And, Lastly, To show that even common Glass is not void of Pores, I shall reduce what I have to say, and comprise it under the following Propositions. PROP. I. It's very probable, that Glass may be pierced into, at some distance, even by visible and tangible Bodies. And besides the Arguments already offered to evince the porosity of Bodies, I shall add, That a certain Spirit of Salt being kept in a Glass in a cool Place, it corroded some Parts so much as to leave them as thin as a piece of Paper; and lined with a white Substance, which seemed to be some of the Alkali of the Glass and Sand corroded by the Saline Spirits of the Menstruum, and coagulated with them into this odd kind of concrete; and this wrought no higher than the Liquor contained in the Glass. And besides this, I had another Vial corroded by a distilled Liquor of Vitriol, which contained more Phlegm than Oil; and to this Relation I shall add, That a Pound of Dantzick Vitriol, and a Pound of Sea-Salt, the one calcined lightly, and the other decrepitated, being distilled in a well coated Retort, by degrees of Fire, giving at the last a very strong one; when the Vessel was taken off, we found that the Heat had here and there melted it; and that the Fluxed Caput Mortuum had corroded the Glass, fetching off Films from it; and those Parts which did not appear to the Eye manifestly wasted; seemed by their brittleness to have been penetrated; so that their Texture was spoiled by the Saline and Vitriolate Particles. PROP. II. Common Glass is not ordinarily permeable by Chemical Liquors, tho' strong and subtle, nor by the directly visible or odorable expirations of Bodies; tho' absolutely speaking, it is permeable to some corporeal Substances. And, First, It is manifest, not only that several Spirituous Liquors and Menstruums, may be kept in Glass Vessels without sweeting through them, but even distilled in them; and I have found that neither Salt of Tartar would lent by being held in a Glass Bubble in the Water, nor would Sal-Armoniac penetrate it, so as to make its way out. But it is to be considered, that some Circumstances may vary these Observations, as when the Texture of Glass is too lax and open; or when the Bodies are vehemently agitated with Heat, or are too subtle; and have a certain congruity with the Pores of the Glass. For I have seen a sort of Glass so soft, that not only hot Liquors, but moderately Corrosives would work upon it; and I have heard, that some sort of Glass is apt to be prejudiced by corrosive Liquors. And I was told by one, That he several times observed Gold to penetrate the Pores of Glass; and I have observed Fumes to make their way through the Pores of ordinary Glass, upon distilling of Spirit of Hartshorn with a strong Fire. And that the Pores of Glass are penetrated by some Substances, is evident, by the Effects of Cold and Heat, on Bodies contained in sealed Glasses; and that so gross a Body as the Effluviums of Earth will penetrate Glass, and work on Iron contained in it: And Light itself appears evidently to be contained in closely sealed Glasses; and by a cantinued Heat, I have found the Parts of Fire to penetrate Glass, and add to the weight of Iron sealed up; and having tried this Experiment with Filings of Copper, I found that their Colour was much altered, some of them being adorned with exceeding vivid Dies; which they yet retain without being increased in weight, as if they were not able to stick themselves fast enough in the Pores of the Metal, to add to its Gravity. And I had a Liquor which would vary its Colour, as if something in the Air was successively communicated to it, and receded again. And to these, other Instances may be brought from what may be observed in painting Glass; for the Pigment being laid upon the Glass, and that placed upon a Bed of Lime, and then continued in a violent Heat, the Pores of the Class will be so opened, as either to imbibe the Parts of the Pigment, or to vitrify and mix with it: And I have found, that by laying prepared Silver upon Glass, and placing that upon live Coals; when it was nealed a while, by giving it a sufficient degree of Heat, the Glass will acquire a Yellow, and almost a Golden Colour, which is not to be washed off; the way of preparing this Silver, is not always the same, the Glass-painters usually adding to it Antimony, Yellow Okre, or the like. But since the Colour proceeds from the penetration of the Silver into the Pores of the Glass; I usually make use of the Powder of Silver calcined, by burning Sulphur upon thin Plates; and I have often coloured Glass barely by the use of Leaves of Silver laid upon the surface of the Glass, and moistened with something to keep it from flying away. And I have often observed that tho' the Glass betwixt and the Light appeared Yellow, yet being held from it, it appeared Blue; which is a Confirmation of what we have inferred from the variation of Colours, in a Tincture of Lignum Nephriticum; Viz. That they may be solved by Mecharical Principles. And that the Colour of Glass tinged, proceeds from an Incorporation of the Parts of a Pigment with it, tho' they penetrate not the whole Substance, but tinge the superficies, (as I observed in Glass Plates, which were part of the Windows of St. Paul's Church before it was burnt) may be urged, since the Parts of the Silver may be wrought on by the fixed Salts in the Glass, and afford different Colours, according to the difference of the Bodies that work upon them, as Copper with Spirit of Urine, give a deep Blue; with Spirit of Salt, a fair Green; and with Aqua Fortis, a Colour partaking of both. And in making Glass of Lead, with Minium and White Sand, or Crystal, the Glass will be of an Amethystine Colour, but if you add a due proportion of calcined Copper, the Metal will give it a good Green; so as to pass for no bad E●ner●uld▪ and I remember, that distilling some Gold in a Retort, amalgamed with such Mercury as would grow Hot with it in the Cold; the Matter did, before it flew away, perfectly slain an Inch in the Diameter of the bottom of the Glass, with a Colour, which, held from the Light, appeared like that of the better sort of Turquoises; but when interposed between the Window and the Eye, appeared of a some what Golden Colour. And Gold incorporated with Mercury, and kept in digestion, when the Fire was once very vehement, it burst the Vessel, and flew away, but tinged the lower part of the Glass quite through, with a glorious Red Colour, not inferior to that of Rubies. CHAP. VIII. Of the Porousness of Animal Bodies. Of the Porosity of Animal Bodies. THE First Argument I shall urge for the Porosity of Animal Bodies, is from their Structure; for since they are most of them compounded of dissimilar, or similar Parts, we cannot suppose those so exactly united as not to leave Pores and Intervals betwixt them, whose Number and Variety must be very great. A Second Argument of their Porosity, may be deduced from the apposition and consumption of their Nutriment; and which may be illustrated by observing that those moist Particles with which the Earth is moistened, being agitated by the Heat of the Sun and Air, those that happen to be commensurate to the Pores of the Root are impelled into it, and thence conveyed into the other Parts of the Tree, being conveyed in the form of Sap, which passing through new strainers receives alterations requisite to turn it into Wood, Bark, Leaves, Fruit, etc. And in young thriving Animals it cannot be imagined, how the nourishment should be conveyed to all the Parts, without supposing them furnished with Pores for its reception and passage. Another Argument of the Porosity of Animal Bodies, may be brought from the plenty of Humours carried off by sweat, and insensible Transpiration. And by the help of good Microscopes we may discern Pores in the skins of Animals, and especially in the inward sides of Gloves which are nothing but skins dressed; and they are further evident, since Quicksilver readily passes through the Pores of Sheep's skins, and leaves the dross behind in the Leather; and the like I have tried with the skin of a Man's Arm tanned, which Pores according to Steno and Malpighius, are the Excretory Vessels of the Glandulae Miliares contained in the skin. And that the skins and shells of Eggs are not void of Pores, appears, since the moisture contained is so far dissipated through them as to diminish their weight. And Sanctorius in his Medicina Statica tells us, that if the Meat and Drink taken one day amounts to eight Pound, five Pound will be carried off by insensible Transpiration. And he elsewhere says, that in the space of twenty four hours ●n the Winter time a healthful Body may exhale fifty ounces or more, a great part of which is carried off through the Pores of the Membranes of the Aspera Arteria: And if one's finger in hot Wether be held to the Surface of any cold Body, it will presently be sullied over with the steams that issue out of the Pores of the skin. And their Porosity is further confirmed by observing, how soon those black and blue spots in the skin occasioned by bruises are removed: for which use Helmont employs white Bryony root, and I have seen a Poultess of chopped Hyssop and fresh Butter remove the Pain, and black colour of a contusion in a little time. And not only the Skins but the Membranes of Bodies are stocked with Pores, since the Bladder of a dead Animal appears to be full of them; for if Salt of Tartar be put into a Bladder, and it be then immersed in Water enough of it will penetrate the Bladder to dissolve the Salt and render it Liquid; and the like succeeded, but much more slowly when the Experiment was tried with Sugar; and some say, that Syrups made this way, instead of using ordinary Water, are much more preferable. And as a further instance of the Porosity of the shells of Eggs, I shall add, that one having been immersed in very sharp Vinegar, tho' the shell was part of it consumed, yet being taken out and wiped, it was considerably swelled and heavier than before, the Menstruum being imbibed and insinuated into the Pores of it. And I am not only told, that the Chineses had a way of salting Eggs, but I found by coating one over with Clay, after it had lain some time in Brine, the substance contained tasted evidently Salt. And I know a Physician who was affected with a giddiness upon the use of Clysters of Sack, and another told me, that having applied Tobacco to the sore Leg of one of his Patients, it caused her Stomach to turn, or actual Vomiting; and another told me, that he used to Vomit himself, by applying Decoctions of Tobacco to his wrists or other extreme Parts, and it is a common custom to Purge Children by the Application of external things; and it hath been observed, that Bathing the sore Heads of Children, with a Decoction of Tobacco hath caused a giddiness. And a Virtuoso told me, that having taken another by the Hand, which was gently besmeared with Oil, it gave him three or four stools presently. And to what hath been delivered of the Porosity of Membranes, I shall add the aptness of Lute-strings, to imbibe into their Pores moist Particles; and also the Metastasis or Translations of Morbific matter in diseased Bodies; as the matter which causes a Fever, being discharged upon the Brain causes a Delirium; and other Distempers as it is discharged upon the Pleura, the Membranes of the Chest, the Throat or Guts. Another Argument of the Porousness of Animal Bodies, may be drawn from their aptness to imbibe Effluvia from without, as when Cantharideses externally applied affect the Bladder; to which instance may be added the effects of Plasters, and Ointments, and Pericarpia; for I have often cured Agues with a Mixture of ●●●ians, Hops, and Bay-Salt; and it is vulgarly known, that Mercury externally used in Ointments will salivate. To which may be added the effects of Periapta and Appensa; of Bloodstones in stopping of Hemorragies, and of another kind of Stone made use of by the Indians in Obstructione Menstruum. And I have found myself that the Moss of a dead Man's skull would stop an Hemorrhage, as soon as warmed by the contiguous skin. And Zwelfer tells us of one who preserved several from the Plague, by using helmont's Troches of Toads in Annulets; and several of these Troches being put upon the Plague sores of the infected, they were afterwards cured by the use of vulgar Remedies. And to these I shall add, that having drawn a Spirit from a Mixture of flowers of Brimstone, powdered Salarmoniack, and good Quicklime in equal quantities, by degrees of fire in a Retort till the sand be red hot, if a piece of Copper be folded up in Sheep's Leather, and held over the Vial it is contained in, the Metal will be tinged with the rising fumes, without discolouring the Leather; and the same will succeed, only more slowly, through a double fold of Leather: And all the alteration the Leather received from these pervading fumes was, that they gave it a sulphureous smell. And this Experiment may favour the accounts we have of the Effects of Lightning, which hath been observed to discolour the money in Men's Pockets, without burning them; and the same effect hath been taken notice of by some, who have ascended a burning Mountain in America. And it is observed, that Lamb's Leather hung up in the Air, acquires a moisture, which adds considerably to its weight. And to these instances may be added, the effects of Cantharideses upon some that only carried them in their Pockets, the Effluviums of them having caused them to piss Bloody Urine. And as a further Confirmation of the Porousness of Bodies I shall subjoin, that the Permeating Liquor above mentioned had the like effect upon Copper, through the tough skin of an Egg, and likewise through a wet Sheep's Bladder; and to confirm what I have said, of the Porousness of Animal Bodies I shall add, that a Gentleman who had a long time a Perforation in his Thorax, and was wont to inject medicated Liquor often to cherish the Parts, and likewise to wear a silken Bag stuffed with Aromaticks upon the Orifice, he not only had the Taste of the Liquors in his Mouth, but the Aromatic Bag, when fresh, would perfume his Breath in Respiration. And Galen tells us, that Honey and Water having been injected into the Thorax, have been discharged through the Aspera Arteria by coughing. And in a Man who was troubled with a dry short Cough, we found some white curdled Matter betwixt the Pleura and the intercostal Muscles, which seemed to occasion the Cough by some noxious Effluvia transmitted to his Lungs. And to these Instances I shall add, that it seems probable that these Humours collected in the Abdomen of an Hydropical Person, can be carrled off no other way but through the Pores of Membranes, upon the use of Diuretic and Purging Medicines. And an Instance not much inferior, is the Translation of the Matter of an Empyreuma, so as to be voided by stool or Urine; and I have observed myself, that when I have been present at the Dissection of a Dog, whose Blood smelled very rank, the Excrements evacuated by siege, some time after, would retain that Odour. And a famous Surgeon and Anatomist relates, That one who was ill of a Dropsey, judged to arise from a Schirrus of the Spleen; by applying a large Sponge dipped in Quick-lime-water, to the Region of the Spleen, the Schirrus was dissolved, and the Hydropical Humour evacuated. And Galen tells us, that part of the Humours collected, upon the breaking of a Bone, is discharged through the Skin, whilst the Callus is a forming. And not to repeat what Arguments have been already made use of, to prove the Porosity of Animal Substances in general; that the Nails of Animals are porous, may be argued from their aptness to be tinged with a Solution of Silver in Aqua Fortis, or of Gold in Aqua Regis; the former giving them a dark and black Colour; and the latter, tinging them with Purple Spots; which would continue, till by the growth of the Nail, they were forced to be pared off. And one thing in these Tinctures worthy our Notice is, that tho' the Menstruums are Acid, and Corrosive, yet the Tinctures are not, the Taste of the Tincture of Silver being bitter, and the other styptic. And the same method may be taken to prove the porosity of Ivory; since a Tincture of Silver in Aqua Fortis will tinge it with a dark and blackish Colour, which is not to be washed off. And I have long since tried, that a Solution of Gold will give it a sine purple Colour; and that too when both the Ivory and the Liquor were cold. Copper dissolved in Aqua Fortis, stains Ivory with a bluish Colour. And even in the Cold without the Use of Corrosives, I have stained Ivory with a permanent Blue, like a Turquois, by suffering a Solution of Copper in Sal-Armoniac to dry upon it. But to return to the Porosity of Bones; it may be argued from the Marrow found in the Cavities of them; since nourishment must needs be conveyed to it, and it is not improbable that Blood Vessels penetrate at the least some depth into the substance of Bones, tho' the Juice received from them, may afterwards be conveyed through the more internal Parts of them; for we see that the Lower Jaw is perforated by a Nerve, and also a Vein and an Artery to carry and return Blood for the Nourishment of the Teeth; and I have been told that Blood-vessels have been observed by good Anatomists, to enter into the substances of larger Bones; and Blood hath not only been observed in the cavities of the Bones of younger Animals, but in the spongy Substance of several larger Bones. To which may be added in favour of their Porosity; the blackness which they acquire when put into a competent heat, and the fatness which they afford; as also their specific Lightness, and their aptness to be corroded with sharp Menstruums. And Bones are observed in moist Wether, not only to grow heavier, but they imbibe the moisture of the Air so much, as evidently to swell. And to these Instances I shall subjoin what Observations I have made on large Ox-bones. Nou. 15. we weighed two (entire or unbroken) Marrowbones, and found the one to weigh twenty nine Ounces half a Dram, and the other twenty four Ounces four Drams and thirty Grains. November 24. The former weighed twenty nine Ounces six Drams, and the latter twenty five Ounces, one Dram, and thirty Grains. December 28. The former weighed twenty nine Ounces, three Drams, and fifty five Grains; and the latter twenty four Ounces, seven Drams, and thirty nine Grains. June 7th, The next Year the former weighed twenty nine Ounces, two Drams; and the latter twenty four Ounces, seven Drams; from whence it appears, that Bones are Porous, since they imbibe and lose moist Effluvia again. And that there may be Vessels fine enough in the substance of Bones, to convey Nourishment, may be rendered probable, by what the Learned Sennertus hath observed, viz. That Hairs being cut in the Plica Polonica, they have been observed to bleed, so that they seem to be made up of a Bundle of cylindrical Pipes. And as a further Instance of the Porosity of Bones, I shall add, that Mercury hath been found lodged in the Bones of those that have been salivated in the Pox. And the same is attested by Eustachius Rudius (apud Sennet.) Lib. 5. de Morbis Acutis, Cap. 15. And what hath been said may serve to favour the Use of Annulets and Periapta; or at least discountenance their being too suddenly rejected. CHAP. IX. Of the Natural History of Human Blood. PART. 1. Containing a List of Titles for the History of Human Blood. Of the Natural History of Human Blood. BEfore I proceed to enumerate the Titles laid down for a Natural History of Human Blood, it may be requisite to advertise, that the first Set which I call primary, and to which those in the Appendix are secondary ones, consist of such as offer themselves to the View at the First sight, which need not be either nicely Methodical, or accommodated to any Hypothesis. The second Class consists of such as are to be ranged into a better order, being of a greater extent and more comprehensive, so that one Topick may be branched into several subordinate ones, or secondary Titles. And from the Materials drawn together under this Head, may be deduced a Set of Titles, reduced into an inchoate Natural History of the Subject they have Relation to. And since the Subject to be treated of is very difficult or comprehensive, as the Generation of Living Creatures, Magnetism, Fermentation, Gravity, etc. it may be useful, if not necessary, to interpose betwixt the Titles of the last, and those of the first Order, a Set of Titles that may be called of the middle Order or Classis; in which the Nature of the Subject is more narrowly looked into. Titles of the first Order for the Natural History of the Blood of Healthy Men. Titles for the Natural History of Blood. I. Of the Colours of Human Blood, Arterial and Venal. II. Of the Taste of Human Blood. III. Of the Odours of Human Blood. iv Of the Heat of freshly emitted Human Blood; which is observed to be much violenter after it hath run a while, than when it first began. The Blood that came out of the Veins of a young Gentlewoman, falling upon the Ball of a Thermoscope, caused the Liquor to ascend above an Inch nearer the smaller and upper Ball of the Glass. And in another Trial it was raised almost as high as to the Ball of an ordinary Thermoscope; but being held in the Blood of a healthful and lusty Man, the Heat raised the tinged Liquor a good way into the upper Ball; which was higher than the Heat of the Air in the Dog-days usually does, and the Blood of a healthful Man continued its Heat so lo long, that it raised the tinged Liquor three or four Finger's breadth when it was coagulated. V Of the inflamability, and some other Qualities of Human Blood. A piece of Human Blood being dried till it was fit to be powdered, and then held in the flame of a Candle, it took Fire, and afforded a flame not much unlike that which caused it, burning with a Crackling noise, and here and there melting; and if it was laid upon live Coals, and now and then blown, it would yield a very yellow Flame, and during its Deflagration, would seem to fry upon the Coals, and in a great measure to melt into a Black Substance almost like Pitch. And some of the Powder of Blood being cast into the flame of a Candle, they took Fire in their passage, and flashed not without some noise, as if they had been Rosin. VI Of the Aerial Parts naturally mixed with Human Blood; and also found in its distinct Parts. VII. Of the Specific Gravity of Human Blood entire. It may be different in several Persons, according to their Sex, Age, Constitution, etc. as also in the same Person, according to the time of the Year, the Day, or, as it is taken out at a less or greater distance from a Meal. But to make an Estimate of its Specific Gravity, we took the Blood of a sound Man, and put it into an oblong Glass; and when it was settled, we marked with a Diamond, that part of the Glass to which the Liquor wrought; and then weighing the Glass, and the Blood contained in a very Tender Balance; we poured out the Blood, and having washed the Vessel, we filled it up to the same Mark, and then weighed it in the same Balance; and then weighing the Glass, and deducting that from the weight of the Glass, and the two Liquors, the Water weighed nine Ounces, six Drams, and fifty Grains. And the Blood equal to it in Bulk, weighed ten Ounces two Drams, and four Grains, so that the Blood being three Drams and fourteen Grains heavier, it was about ●/2● part heavier than Water. VIII. Of the Specific Gravity of the Fibrous and Red part; and of the serous part of the Blood. IX. Of the Consistence of entire Human Blood. X. Of the Disposition of Human Blood to Concretion; and the time wherein it was performed. XI. Of the Liquors and Salts that coagulate Human Blood. Clotted Blood being kept some Hours in Spirit of Wine, which is a Menstruum fit to dissolve some Bodies, it was taken out as hard as if it had been dried by the Fire. XII. Of the Liquors and Salts that obstruct or dissolve its Coagulation. XIII. Of the Liquors, etc. that preserve Human Blood. XIV. Of the Mixture that Human Blood may receive from Aliments. XV. Of the spontaneous or Natural Analysis of Human Blood into a serous and a fibrous Part. XVI. Of the respective Quantities of the serous and fibrous part of Human Blood. XVII. Of the differences betwixt the serous, and the Red part of Human Blood. XVIII. Of the Artificial or Chemical Analysis of Human Blood; and first of its Spirit. XIX. Of the Volatile Salt of Human Blood, and of its Figures. This Salt is so fusible, that one part of it may be brought to boil, whilst the other flies way; and this Observation will hold in most Volatile Salts. And tho' this Salt, when sublimed, looks white and Clean, and a very homogeneous substance, yet I am apt to think, that it is made up of Parts of Matter of sizes and shapes different enough, for having weighed some Grains of resublimed Salt of Human Blood, that seemed pure, its smell was very strong and diffusive, so that one would have expected it to fly away in a little time, but we observed that it was very little diminished in seven or eight days time; yet what remained had lost its Odour, but retained a saline Taste; and being put upon a Solution of Sublimate in common Water, turned it White, so that its diffusive and penetrant Humour seemed to depend on some more volatile Parts of the Blood. But it may be a Question to be solved by further Experience, whether the fixedness of this Salt may not proceed from the Coalition of an Acid Salt in the Air. A Dram of Volatile Salt of Human Blood sublimed in a Lamp-furnace, was put into common Water, and when a Thermoscope was brought to its right temper, being immersed in this mixture, the tinged Spirit of Wine manifestly subsided about 2/10 parts of an Inch; tho' a considerable part of the Salt lay undissolved in the bottom of the Water. And when the Liquor would descend no further, we added to the Solution strong Spirit of Nitre, till it would no longer make a manifest Conflict with the Salt; and then we observed, that whilst the Conflict lasted, the Spirit of Wine risen above three Inches and a half higher than the station it stood at before. The figure of this Salt may be either considered in reference to single Grains, or an Aggregate of them, when they are raised and sublimed to the top of the Glass; the latter of which may be best observed, when they fasten themselves to the inside of the Glass that is set to receive them; for in the beginning of the Operation, one may observe the little saline Concretions to lie in rows, sometimes strait enough, and sometimes more or less crooked, with different Coherings and Interferings, so that they sometimes represent either Trees, or their Branches or Hartshorn, etc. which are casual figurations depending on several accidental causes and circumstances, as the degree of fire made use of to sublime the Salt, the quantity of the ascending matter in reference to the Capacity of the Vessel that receives it. And the like diversity of Configurations I have observed amongst the Salts of other Volatile Salts, as well as those of Human Blood. And as for the single grains of the Salt of Human Blood, I discovered a good many of them to be finely shaped; but whether they were accidental or not, experience must determine. But these figures were only observed in the sublimate of the first Distillation, for those obtained by rectifying the Salt and distilling it again, were of a considerable bigness and solidity tho' differently shaped, some of them being Cubes, others Parallelopipeds, others Octoedrons', being almost like grains of Allom; but most of them prettily shaped; being comprehended by Planes, smooth, finely figured, and aptly terminating in solid Angles, as if the concretions had been cut and polished. Another way I took to discover the figures of the Salts of the Blood, was to rectify the Spirit, so that it may be fully satiated with the Salt, whilst the Liquor continues warm; for when it is refrigerated, a number of saline Concretions of different sizes, several of which shoot into very smooth Crystalline Plates prettily figured, having their broad and parallel Surfaces of an Hexagonal or an Octogonal figure, regular enough. A drachm of dry Volatile Salt of Blood, being dissolved in some distilled Water, we dropped into it good Spirit of Nitre, till the two Liquors would no longer manifestly act one upon another, and when the conflict ceased, we slowly evaporated the superfivous moisture, which steamed almost all away before the saline part would coagulate. At length it became dry, and the middlemost part appeared in the form of thin Crystals, not unlike those of Salt Petre; but the rest which was by much the greatest part of the Concretion, seemed to be a confused mass without any distinct figure; and this mass weighed but twelve grains above a drachm; so that Volatile Salt of Blood may be satiated with a fifth part of its weight of the saline Parts of Spirit of Nitre. This Salt exposed to the open Air in a window was very apt to run per Deliquium, and a little of it being put upon a live Coal, it melted and seemed to boil; and towards the end made a noise, and afforded a flame yellower than that of common Nitre. XX. Of the Phlegm of distilled Human Blood. XXI. Of the two Oils of Human Blood. By distillation in a Retort, it affords an Empyreumatical and a very fetid Oil, whose colour is almost black; which seems to be occasioned by the increase and opacous redness of the Liquor, since some of it being spread thin upon Glass, and held against the light, appeared yellow, or of a reddish colour, as they lay thicker or thinner upon it, but when it was well dried before committed to Distillation, it yielded a greater quantity of Oil, so that once out of a Pound of not over-dryed Blood, we obtained an ounce and a half of Oil, and from another we had a much greater quantity of Oil. And having once prepared Blood by a convenient Digestion, and rectified very carefully the distilled Liquor that came over with the flame of a Lamp, I obtained amongst other things two Oils of very different colours; the one being of a pale Amber or yellow colour, and the other of a deep red; and tho' these Oils were both of them afforded by the same Blood, and were clear and pure enough; yet they would swim in distinct Masses one over another, and if mixed by shaking would again separate like Oil and Water. Whether the difference in specific Gravity betwixt these two Oils, kept them from mixing permanently, as well as it kept them distinct before they were mixed; or whether the seeming incongruity proceeded from the Texture of these Liquors I shall not now stay to dispute. To show that the Oil of Human Blood contains several saline Particles, capable of being separated from it, we put a parcel of unrectified Oil, to a convenient quantity of distilled Water, and having mixed them sufficiently by agitation, so that the Water might rob the Oil of its separate saline Particles, the event was that after the Liquors were well settled, the Water was found to be impregnated with saline Particles, that it obtained by dissilution from the Oil; so that it acquired a moderately brisk taste, and would readily turn Syrup of Violets green; and precipitate a white Powder out of a solution of Sublimate; but whether the like will succeed with other Empyreumatical Oils or not, drawn from Bodies belonging to the Animal Kingdom, I shall leave others to determine. Having put some unrectified Oil of Human Blood into a concave piece of Glass, and then dropped as much Oil of Vitriol into it, as might amount to a third or fourth part of the fetid Oil, we stirred them together with a slender piece of solid Glass, upon which the Mixture emitted store of whitish fumes or Smoke; and acquired a considerable degree of Heat, so that tho' it amounted to not much more than a spoonful, yet I was not able to hold my finger under that Part of the Glass, that contained the Liquor. Having taken some Empyreumatical Oil of Human Blood unrectified, tho' it was dark, and gross, and muddy, yet it would easily in the cold dissolve in rectified Urinous Spirits, to which it gave a reddish colour deep enough. XXII. Of the fixed Salt of Human Blood. To obtain but one ounce of it, there is requisite to employ a considerable quantity of Blood; and duly prepared by a very obstinate fire; for the Caput Mortuum being kept three or four hours in the fire, it will yield no fixed Salt at all: But having by an obstinate Calcination obtained three or four drachms of this Salt, I found that it was of the Nature of common or Sea-salt, tho' a little different; for it tasted like it, and a strong solution did not readily turn Syrup of Violets green, nor precipitate a Brick colour, or brownish yellow, no more than a white Powder, out of a solution of Sublimate; nor did the Spirit of Salt dissolve it as an Alkaly. And having put a little Oil of Vitriol upon our dried Salt, it immediately, as it several times did upon common Salt, corroded it with great violence, and with much foam and Smoke. We also dropped a little of it dissolved in Water, upon a solution of Silver made in Aqua Fortis, upon which a white Powder was immediately precipitated: And having put some Leaf-Gold upon Aqua Fortis, which would not work upon it, whilst it was swimming there without being so much as discoloured, I put a little of our powdered Salt into it, which being thereby turned into a kind of Liquor, did without the assistance of Heat, presently dissolve it. XXIII. Of the Terra Damnata of Human Blood. From twenty four ounces of dried Blood, we got after two days Calcination, but two drachms and nine grains of Earth; which probably was not pure Earth, since it had a red colour like that of Colchotar of Vitriol. XXIV. Of the Proportion of the differing Substances Chemically obtained from Human Blood. they are scarce to be determined, not only because of the sometimes great disparity, as to proportion, that may be met with of the fibrous part to the Serum, in the Blood of several Persons; but of the same, according to different Circumstances, and also, because it is hard to distil the pulverised part of the Blood; since no one hath so much as taken notice of the Necessity of shifting the Retort, to gain as much Volatile Substance as may be obtained; and leave as little as may be in the Caput Mortuum. For having distilled a quantity of dried Blood, the same Heat which made the lower part pass in the form of Exhalations into the Receiver, made the matter to swell, so that it lifted up a considerable quantity of Black Matter to the upper part of the Vessel, which a common Distiller would have called a Caput Mortuum, tho' to a discerning Eye, it appeared to be of the same Nature with the Matter first put in, tho' blackened by the ascending Fumes, therefore taking it out, and mixing it with the remaining Substance, that was more of the Nature of Caput Mortuum; it was committed again to Distillation in another Retort, whereby we obtained more Oil, etc. And perceiving that even this Caput Mortuum had upon the top of it, a pretty deal of Matter, which was not sufficiently despirited, I caused it to be distilled again in a fresh Retort, in which it afforded a not contemptible quantity of Volatile Matter. And having thus in three Retorts distilled twenty four Ounces of dried Human Blood, we obtained of Volatile Substances, viz. Spirit, together with a little Phlegm, White Salt, and very high coloured Oil thirteen Ounces and one Dram, besides several parcels of thick Oil that stuck to the Retorts and the Receiver, which we judged to be seven Drams more; so that the whole Quantity of the Volatile Part amounted to fourteen Ounces, of which the Oil was six Ounces six Drams, and the clear Liquor six Ounces, three Drams and a half, besides the Volatile Salt, which, when the Spirit was drained from it, appeared white but wet; so that it was not possible to determine exactly, neither how much Liquor it yet retained, nor how much itself weighed; but it will be no hard matter to guests near the Truth to any Man that knows, that having carefully sublimed the Salt, there remained in the Glass two Drams and five Grains of Phlegmatic Liquor; which was not wholly void of Salt; and of Volatile Salt in a dry form, we obtained one Ounce and two Drams and a half; the Caput Mortuum amounting to eight Ounces and a half, and somewhat more, which being calcined for two or three Days together, afforded not White, but brounish-red Ashes, whence we obtained seven Drams ¼ of White and fixed, but not a truly lixiviate Salt; and two Drams and nine Grains of Earth. But indeed considering the great proportion of each of these Substances lost in distillations, it will, upon that account, be a hard matter to determine the true proportion of the Principles of Human Blood. XXV. Of the Fermentation or Putrefaction of Human Blood and its Phaenomena. XXVI. Of the Mechanical Uses of Human Blood, as in Husbandry, etc. XXVII. Of the Chemical Uses of Human Blood. XXVIII. Of the Medicinal Uses of Human Blood. XXIX. Of the difference betwixt Human Blood, as it's found in sound Persons, differently constituted, and circumstantiated, as Men, Women (when Monstrous and when not) Children, Moors, Negro, etc. XXX. Of the affinity and difference betwixt the Blood of Men, and that of several other Animals, as Quadrupeds, Birds, Fishes, and Sanguineous Infects. XXXI. Paralipomena relating to the History of Human Blood. XXXII. Micellaneous Observations, Experiments and Inquiries about Human Blood. Were this Treatise applied to any other than extravasated Blood, to these we might add the following Titles. I. Of the process of Sanguification, or the series of changes that the Aliment successively undergoes, from its first being taken in at the mouth, till it be turned into Blood. II. Of the motions of the mass of Blood, and particularly its Circulation. III. Of the Chyle, Lympha, and other Liquors, that are supposed to enter and mingle with the Blood. iv Whether Phlegm, Gall and Melancholy, be constituent Parts of the Blood. V Whether some other Substances may not, with as much reason be admitted into the composition of the Blood. Titles of the first Classis, for the natural History of Human Urine. 1 Titles for the Natural History of Human Urine. I. Of the colours of Human Urine. II. Of the taste of Human Urine. III. Of the Odours of Human Urine fresh and putrified. iv Of the Heat and Cold of Human Urine. V Of the specific Gravity of Human Urine. VI Of the Consistence of Human Urine, as to Density, Viscosity, etc. VII. Of the Aerial Parts contained in Human Urine. VIII. Whether Human Urine is a fit Liquor for Fermentation properly so called. IX. Of the differences betwixt fresh and stolen Human Urine. X. Of the Fermentation or Putrefaction of it, and the time it requires. XI. Of its Spontaneous separation of Parts. XII. Of its Vulgar Analysis by Distillation. XIII. Of some other ways of distilling Human Urine. XIV. Of the proportion of the Principles, or Ingredients of Human Blood. XV. Of the Spirits of Human Urine. XVI. Of the Phlegm of Human Urine. XVII. Of the Volatile Salt of Human Urine. XVIII. Of the fixed Salt of Human Urine. XIX. Of the compounded Salts of Human Urine. XX. Of the shining Substance obtainable from Human Urine. XXI. Of the Salt that is Predominant. XXII. Of the Empyreumatical Oils of Human Urine. XXIII. Of the Mellago, or Rob of Human Urine, and its uses. XXIV. Of the Terra Damnata. XXX. Of some accidental differences of Human Urine, as it's emitted in the Morning, or at certain distances from Meat, or after the use of certain Aliments, or Medicaments, as Asparagus, Turpentine, etc. Or at different seasons of the year, as Winter, Summer, etc. XXVI. Of the affinity of Human Urine with divers other Bodies, especially Vegetables and Minerals. XXVII. Of the Hostility of Human Urine with Acids, etc. XXVIII. Of the affinity and difference betwixt Human Blood, Urine, Gall, Milk, etc. and divers Liquors, or Juices belonging to the Animal Kingdom; particularly of the comparison betwixt Human Urine and that of Beasts. XXIX. Of the Mechanical uses of Human Urine. XXX. Of the Chemical uses of Human Urine, and its Parts, especially as a Menstruum. XXXI. Of the Medicinal uses of Human Urine External and Internal. XXXII. Paralipomena relating to the History of Human Urine. XXXIII. Promiscuous Observations, Experiments and Inquiries about Human Urine. The second Part of the Natural History of Human Blood, containing Miscellaneous Experiments and Observations about Human Urine. The third Part containing Promiscuous Experiments and Observations, about the Serum of Human Blood. HAving separately weighed the Serum, and the consistent part of the Blood, the latter weighed four ounces, six drachms and a half, and the former three ounces, six drachms. And having taken the same measures with the Blood drawn from another Person, the fibrous part weighed four ounces, five drachms, and the Serum four ounces. But from these Experiments it does not follow, that the fibrous part is alone heavier than the Serum; since a great deal of the latter is dispersed through the Pores of the former, which appears, since four ounces, five drachms, and thirty four grains of the fibrous part of Blood being distilled in a digestive Furnace, the dried Blood remaining weighed but one ounce, three drachms, and thirty four grains; whereas the serous Liquor distilled from it amounted to three ounces, fifty three grains; and the like trial being again repeated with another parcel of Blood, the dried mass amounted to one ounce, six drachms, and fifty grains; and the Phlegmatic Liquor distilled from it, to seven ounces. Red Sealing-Wax suspended at a Hair, weighed in the Air one drachm, fifty six grains; in Water thirty five; in Serum thirty three. And having made use of an Instrument purposely made, when common Water weighed 253 grains, an equal bulk of Serum weighed 302; and the Serum of the Blood of another Person being weighed, it wanted but two grains of the weight of the former. Serum which was tinged with Blood being strained through Cap-Paper, the Liquor which passed through it was of a yellow colour. Spirit of Salt being dropped into Serum, coagulated some Parts, which subsided in the form of Cheese-Curd; and Oil of Vitriol had the same effect, but more powerfully: But Spirit of Salarmoniack rather made it fluid. Oil of Tartar per Deliquium produced a white Curd, by uniting with some Parts of the Serum, but not so powerfully as the other had done. Spirit of Wine rectified produced a copious white Curd, but so soft that it swum upon the top of the Liquor. Upon an infusion of a solution of Sublimate, it yielded a white Curd; but some of the Serum of Human Blood being poured upon filings of Iron, the Liquor dissolved some of the Steel; which appeared, since upon an addition of some of an infusion of Galls, the Liquor which before was muddy and thick, laid down a whitish Sediment; and a convenient quantity of the infusion being added, the two Liquors united into a consistent Body, wherein the Eye discovered no distinct Liquor at all. But having put some of our Liquor upon filings of Copper, which, when wrought upon by Bodies that have in them any thing of Urinous Salt, usually give a conspicuous Tincture, we accordingly found, that the Metal was in a few hours discoloured by the Menstruum; and afterwards it began gradually to grow more blue, and in a day was of a deep Ceruleous colour: And to show that this colour proceeded from some Volatile Salt latent in the Serum, we mixed some of it with Syrup of Violets, and found that it appeared of a fine green. And one thing observable in the Serum impregnated with Copper was, that I kept it several weeks in my Window without perceiving that it in the least sunk. About two ounces of Serum was left in a South Window three weeks in the Month of July; but did not appear in the least putrified; but had let down a considerable Sediment, and in three or four days after it stunk offensively; and that at the same time it was void of Acidity appeared, since it would not take off the blue colour of a Tincture of Lignum Nephriticum. This fetid Serum being distilled in a low Cucurbite, the Liquor that first came over was so little Spirituous or Saline, that it would not in an hours time turn Syrup of Violets green; yet that it was not without a Volatile Alkaly appeared, since being dropped into a good solution of Sublimate, it caused it to lay down a white precipitate. Serum of Human Blood filtered through Cap-Paper, being distilled in a small Retort placed in a Sand Furnace; we obtained only a few drops of a darkish red Oil, some of which subsided to the bottom of the other Liquor, but the greater part swum upon it; and after a good deal of insipid Phlegm had been drawn off, there came over a good proportion of Spirituous Liquor, which smelled almost like the Spirit of Blood, and contained a pretty deal of Volatile Alkaly; so that it would readily turn Syrup of Violets green, and cause a white precipitate, and ferment with Spirit of Salt. And this Spirit being rectified in a small Head and Body, a good quantity of a thick Substance like Honey was left in the bottom of the Glass, which was for the most part of a dark red, and seemed to contain more Oil than appeared upon the first Distillation. The Liquor that came over the Helm was purer, but not stronger than the first; but having put it into a Glass-Egg with a slender Neck, and given the Vessel a convenient Situation in hot Sand, we obtained a Volatile Alkaly, that sublimed into the Neck in the form of a white Salt; from whence it seems to follow, that the serous part of the Blood affords the same Elementary Principles or Similar Substances, both as to number and kind, as the fibrous and consistent part, tho' not as to quantity; that of the Oil and dry Salt being less in a determinate proportion of Serum, than of Blood. Tho' it be necessary, to loosen the Spirit of Urine from the more drossy Parts of it, that before Distillation it should putrefy for about six weeks, yet if fresh Urine be poured upon Quicklime a great part of the Spirit will presently be united, and ascend in Distillation: Encouraged by which Observation, I mixed Serum with Quicklime, upon which there ensued a transient Heat; and this mixed Body being committed to Distillation, first it afforded a Phlegm in a gentle fire; and then in a stronger, a moderate quantity of Liquor, that was thought to smell manifestly of the Lime, but had not a brisk taste; and this was accompanied with a greater quantity of fetid Oil than was expected. The other Liquor being slowly rectified, the Spirit which first came over had a strong and piercing smell, but less rank than common Spirit of Human Blood: Its taste was somewhat fiery, and being dropped upon Spirit of Violets it presently turned it green; in a solution of sublimate with Water, and another of Quicksilver in Aqua Fortis, it presently made two white precipitates. And being mingled with some good Spirit of Sea-Salt, there appeared a thick and whitish Smoke, but neither any visible conflict nor bubbles; yet the colour of the Spirit of Salt seemed much heightened by this operation. And here I shall observe, that having set the lately mentioned Mixture of the Spirit of Serum and of Salt to evaporate, the Salt afforded by it was not like that of Salarmoniack, but the colour produced in the Mixture whilst fluid, was so heightened in the Concrete, that it appeared of a Blood-red colour; but of such a confused shape, that it could not be reduced to any kind of Salt; by all which Phaenomena this Spirit of the serous part of the Blood, seems to be very near of kin to that of the concreted mass. To try whether the fixed Salt of Pot-ashes would have the same effect on Serum of Human Blood, to four Parts of Liquor we put one of Salt, and having distilled them slowly in a Glass-Head and Body, we obtained a good store of a Liquor, but not near so strong as that drawn off from Quicklime; and having rectified this Spirit by a gentle Heat, the two first spoonfuls which rose were not Spirituous▪ but Phlegmatic; nor would it turn Syrup of Violets green, tho' it afforded a light Sublimate when put upon a solution of Sublimate. Having put one part of Salt of Pot-ashes into three of Human Urine, and slowly distilled them in a Head and Body; first a Spirituous Liquor ascended; which being set aside, we continued the Distillation till the remains appeared dry: in which operation we obtained not one drop of oil; besides which it was observable that this Spirit of Urine was not near so fetid, as that made the common way; and that that Liquor which came over at the latter end of the Distillation, was so unlike that which the Serum of the Blood affords us, that it was not only considerably strong, and manifestly stronger than that which first ascended, but had a penetrateing and fiery taste which left a lasting impression upon the Tongue, and made a notable Ebullition with Spirit of Salt, which the Spirit of Urine drawn from Quicklime did not; and whereas in the last Liquor I never observed any Volatile Salt to ascend in a dry form, in the operation made by the help of Salt of Pot-ashes, there ascended without Rectification, several grains of Volatile Salt, one of which was Crystalline and very large, so that it appeared to be like a Plate curiously figured; but some lesser corns of Salt hiding one part of it, I could not clearly discern whether it were Hexagonal or Octagonal. And this Experiment being repeated a second time, the Liquor ascending was more Phlegmatic, tho' we both times applied Salt of Pot-ashes taken out of the same Vessel, and the Urine of the same Person; but this Liquor being rectified per se, afforded more of a brisk saline Spirit, from which we obtained a pretty quantity of Volatile Salt in a dry form, and of a very white colour. Having put betwixt two and three ounces of Serum of Human Blood into a Bolt-head, capable of holding four times as much, and having sealed the Glass Hermetically, and set it aside, we observed the following Particulars. First, No alteration appeared in the Liquor for twelve Months, nor were any Worms or Maggots bred in it; and tho' it be generally believed, that Infects naturally breed in the fluid Parts of Human Bodies, yet I have observed, that if Blood be so exactly closed up, that Flies cannot blow upon it, and that too before it is putrified, or blowed upon, it will not breed them. But, Secondly, In this Liquor there appeared not the least Mother which usually accompanies Putrefaction; but the tip of the sealed Glass being broken off, a pretty deal of Air rushed out with a considarable noise; and that this Air had been considerably compressed, whilst it was penned up appeared, since upon its eruption a multitude of bubbles remained on the Surface of the Liquor, as upon the opening of Bottled Drink, or other Liquors, when the Vessels they are contained in come to be unstopped. And to these Observations, I shall add, that some Sheep's Blood being shut up in Vacuo, upon a gentle Putrefaction, the Elastic and Aerial Particles that were produced blue it up, with a surprising noise. But, Thirdly, The smell of our Serum was strong but not Cadavarous; rather resembling that of the Tincture of Sulphur made with Salt of Tartar and Spirit of Wine, or some such Sulphureous preparation. Fourthly, This Serum being committed to Distillation in a small Glass Head and Body in a digestive Furnace, the Liquor which first came over, first smelled strong enough, yet tasted not at all brisk or spirituous, like that distilled from putrefied Urine, nor did it presently give a manifest greenness to Syrup of Violets; but in a solution of Sublimate, it had the same effect with Spirit of Urine or a Volatile Salt. And having mixed some of it with Syrup of Violets, spread all night upon white Paper, and another parcel of it with filings of Copper, the former in the Morning was turned green; and the latter was so far dissolved, as to leave a large blue stain upon the Paper. One part of Salt of Tartar being dissolved in eight Parts of Serum of Human Blood, and stirred over a gentle Heat, it was not turned red by it as Milk is. That Blood will be coagulated by Heat in a short time into a kind of Jelly, is a common Observation. But having put Spirit of Human Blood into Serum, and kept it a convenient time over a fire, the Volatile Alkaly seemed to make the coagulation more slow. And this effect was more considerable, when we tried another parcel of Serum with Salt of Tartar instead of Spirit of Blood. The fourth Part, containing the History of the Spirit of Blood, begun. BEfore I proceed to the Titles belonging to this Part of the History, it will be requisite to advertise, First, that the Spirit made use of in the following Trials and Observations, was drawn from Human Blood without any Sand, Day, or other Additament; and that the fir●● Distillations were performed in Retorts placed in Sand, care being taken that the Vessels should not be too much filled, because Blood if not well dried is apt to swell, and pass into the neck of the Retort, if not into the Receiver. Secondly, It is to be observed, that the Blood we made use of, was such as was drawn from People, who frequently bleeded by way of prevention. Thirdly, There is so great a Cognation betwixt the Spirit, and Volatile Salt of Human Blood, that the latter seems to be the former only in a dry form. A List of Secondary Titles, concerning the Spirit of Human Blood. Of the History of Human Blood I. Whether Human Blood may be so ordered by Fermentation or Putrefaction, as that in Distillation, a Spirit either Urinous or Vinous may ascend before the Phlegm. II. Whether Spirit of Human Blood be really any thing, but the Volatile Salt and Phlegm well commixed. III. Of the Species of Saline Bodies, to which Spirit of Human Blood is to be referred. iv Whether Spirit of Human Blood be differing from Spirit of Urine, and other Spirits that are called Volatile Alkalies. V Of the quantity of Spirit contained in Human Blood, whether accompanied with Serum or dried. VI Of the specific Gravity of Spirit of Human Blood. VII. Of the Odour, Taste, Colour, transparency and consistency of the Spirit of Human Blood. VIII. Of the dissolutive power of the Spirit of Human Blood. IX. Of the Tinctures that may be drawn by Spirit of Human Blood. X. Of the coagulative power of the Spirit of Human Blood. XI. Of the precipitating power of Spirit of Human Blood. XII. Of the Affinity betwixt Spirit of Human Blood, and some Chemical Oils and Urinous Spirits. XIII. Of the relation betwixt Spirit of Human Blood and the Air. XIV. Of the Hostility of Human Blood with Acids, whether in the form of Liquors or Fumes. XV. Of the Medicinal Virtues of Spirit of Human Blood externally applied. XVI. Of the Medicinal Virtues of Spirit of Human Blood internally given in Pleurisies, head-aches, Coughs, Fevers, Scurvies, Cachexies, Dropsies, Fits of the Mother. XVII. Paralipomena, and promiscuous Experiments and Observations concerning the Spirit of Human Blood. TITLE I. Whether Human Blood may be so ordered by Fermentation or Putrefaction, as that in Distillation a Spirit either urinous or Vinous may ascend before the Phlegm. COnsidering that Fevers have been looked upon to proceed from a Fermentation in the Blood; and likewise, that Human Urine which hath a great Cognation with Human Blood, will not whilst fresh afford a Spirit, till the Phlegm be first drawn off; this Subject of this Title may not appear Groundless. But I am not much encouraged to expect a Vinous or ardent Spirit from Human Blood, nor am I sure there is any such thing as Fermentation in Human Blood. And on this occasion I shall add, that having once kept Blood Hermetically sealed up in a Glass for twelve Months, when it came to be opened, it smelled so offensively, that we could not make any trial upon it; and another time having digested, in a pretty large Vial Hermetically sealed some Sheep's Blood; when it had been a good while in the digestive Furnace, it suddenly broke with a considerable noise, and blew off the long neck of the Vial. And here, to what hath been laid down, I shall add, That some Ounces of Serum of Blood being added to a fourth Part of Raisins of the Sun stoned, and kept in a Glass, in a warm Room for several days; the event of this trial was, that within in a few Days the Raisins began to emerge, and whilst they floated, yielded a considerable quantity of springy and permanent Air; from whence it appeared, that there had been some Degree of Fermentation. But when this Serum came to be distilled, tho' it did not stink as if it had been putrified, yet the Spirit which first ascended, tasted not like a-Viscous Spirit, nor like a mere Phlegm. Whether the Fermentation observed in this Liquor, depended on the whole Serum, or only on the Aqueous Parts distinct from it, I shall leave to Experience to determine. To try whether Digestion or Putrefaction would so open the Texture of Blood, as to make it part with its Spirit more easily, and before the Phlegm, I kept a quantity of Serum for that purpose, four times as long as was sufficient to make Urine part with its Spirit before its Phlegm, but the Liquor which came over by a gentle heat, had but little strength either in Smell or Taste; nor would it readily turn Syrup of Violets Green; yet like a Volatile Alkaly, it would soon turn a Solution of Sublimate in fair Water, into a White, Opacous, and almost Milky Liquor. TITLE II. Whether Spirit of Human Blood be really any thing but the Volatile Salt and Phlegm well commixed. FOR several Reasons I am inclined to believe, that the Spirit of Human Blood is totally composed of a Volatile Salt, and a Phlegm which is not so pure and Elementary, but that some Particles of Oil, and others of Salt, may be mixed with it; and whether by frequent Rectifications this Phlegm may be rendered Homogeneous I much question, since I am not sure, but that in frequent Distillations, some Particles of the Fire mny be from time to time associated with the Liquor; and even in the first Distillation, the Fire uniting with the Liquor, may form one different from the Ingredients or Principles of the Body; and I have found that Woods afford by distillation, a Liquor which is not an Oil, nor an Acid, or an Alkaly, and yet no true Phlegm, but an Adiaphorous Liquor. And on this occasion to show, That the Composition of a Body may as well be made known by investigating the way of generating or producing it, as by that of Analysing or resolving it; I shall add, that having dissolved as much Volatile Salt of Human Blood in distilled Water, as the Liquor would take up, and then having distilled it in a conveniently shaped Vessel, with a regulated degree of Heat, the Distillation afforded us such a Liquor as was desired, since by Smell and Taste it appeared to be a good brisk Spirit of Human Blood. And this Experiment was again repeated with the like success. TITLE III. Of the Species of Saline Bodies, to which the Spirit of Human Blood is to be referred. THO' it be generally allowed that Saline Spirits are of two sorts, yet it may not be amiss to add, That some of them are Acid in Taste, as Spirit of Nitre, Vitriol, etc. Others are rather like common or lixiviate Salts; and their different Effects and Operations are much less alike than their Taste, for upon their mixture, there ensues a manifest conflict, and usually one will precipitate the Bodies, the other will dissolve. And amongst Salts called Alkalies, some are fixed in considerable Degrees of Fire, and others, who take Acid and Alkalies for the true Principles of mixed Bodies, call the one Fixed, and the other Volatile Alkalies. And tho' I, who question this Doctrine, often call the Salts made by Combustion, simply Alkalies, or lixiviate Salts, and those that ascend, sometimes urinous, and sometimes Volatile Salts, yet since the Names of Fixed Alkalies and Volatile ones are in request now, I shall now make use of them in that Sense. These Things being premised, I shall proceed to observe, that notwithstanding that some Physicians and Chemists ascribe Digestion to an Acid Ferment in the Stomach, yet the Spirit of Human Blood is referrable to that Classis, which many call Volatile Alkalies, since it generally performs what Volatile Alkalies are said to do; for it will ferment with Acids, turn Syrup of Violets Green, and precipitate a Solution of Sublimate in common Water. Were I sure that the Ferment of the Stomach were Acid, I should be apt to believe, that the Blood retains something of Acidity in it; but yet that would not be an Argument why I should not refer the Spirit of Human Blood to the Class of Alkalies, because so few Acid Particles would either be destroyed by the Alkalizate ones, that are so abundant in the Spirit, or at least they would be so very much predominant as to give us Reason on their account to denominate, the Mixture Alkalious. As if some drops of Spirit of Vinegar were mixed with stolen Urine, they would be either deprived of their Acidity by some Particles of a contrary Nature, or be so overpowered by the Fugitive Salts they abound with, that the Mixture might well be referred to the Classis of Volatile Urinous Salts. TITLE IU. Whether the Spirit of Human Blood be differing from Spirit of Urine, and other Salts called Volatile Alkalies. UPON this Occasion I shall offer, that not to intimate that a Body may have many similar Qualities, in respect of another Body, and yet distinct Operations on a third Substance: I say, not to intimate that, there may be a considerable difference betwixt Volatile Salts or Spirits, as they are commonly prepared, and when prepared as they may, by reiterated Rectifications, and other ways of Depuration by a dextrous Chemist, to bring them to a greater degree of Purity and Simplicity; a greater degree I say, because it may be difficult to bring them to an absolute Purity, since unheeded commixtures may be made, upon the Account of some Corpuscles of Fire with the Body they work upon. And that there is a manifest difference betwixt Spirit of Human Blood and other Alkalies, as Spirit of Urine and Hartshorn, is evident to several People who, tho' they abhor the Odour of Spirit of Blood, yet they will with Pleasure hold their Noses a great while over Spirit of Urine and Salarmoniack. And tho' from a due proportion of Spirit of Urine or Salarmoniack with Spirit of Salt, I have got a Salt which shoots into the shape of that of Urine or Salarmoniack yet I have seldom, if ever, obtained a Salt of the like shape from a Mixture of the Spirit of Humane Blood with that of Common Salt, for though upon an Evaporation of the superfluous Moisture, the Salts would coagulate together, yet the Concretion seemed confused, and not of the Regular shapes of those Salts, resulting from a Mixture of the Spirit of Sea-Salt with Urinous Spirits. And Helmont tells us, that the Spirit of Human Blood will cure Epilepsies, which Spirit of Urine will not do. TITLE V Of the Quantity of Spirit contained in Human Blood, whether accompanied with its Serum, or dried. THIS is not easy to determine, since some men's Blood is much more Phlegmatic than others, or more Serous, which may of itself be more Spirituous, according to the Complexion, Age, Sex, etc. of the Person that Bleeds. Twelve Ounces of Healthy Human Blood, afforded us seven Ounces and a half of Phlegm, and consequently about Four Ounces and a half of dry stuff. And having distilled in a Retort, in a Sand Furnace, seven Ounces of well dried Blood, we obtained about an eighth part of Spirit, which, tho' not rectified, left in the Receiver and Viol I kept it in, a good deal of Volatile Salt undissolved, which a Phlegmatic Liquor would not have done. And if Spirit of Blood be but a Salt and Phlegm united, We may well suppose, that Human Blood yields a far greater Proportion of Spirit than this, since from the seven Ounces of dried Blood, we obtained about five Drachms of Volatile Salt, which had it been united with a due quantity of Phlegm, it would probably have afforded us near two Ounces more of a Liquor deserving the Name of Spirit. TITLE VI Of the Consistence and Specific Gravity of Human Blood. A Compact Body, which in the Air weighed fifty eight Grains, and in Water weighed six Grains and ¾, in rectified Spirit of Human Blood weighed but five Grains and ¼; and what was considerable, was, That a piece of Amber would not subside to the Bottom, but kept floating upon the Top, and if plunged into it, would emerge again. As for the Degree of the Fluidity of the Blood, or its immunity from Tenaciousness, tho' divers other Alkalizated Liquors, as Oil of Tartar per deliquium, fixed Nitre resolved per deliquium, a Solution of Pot-Ashes, are sensibly unctuous, and but languidly fluid, yet I observed that Spirit of Human Blood did not appear more Unctuous than common Water. And whereas it is commonly found, That as Liquors are more spirituous, so the Bubbles raised by Agitation, soon disappear; I have observed that the Spirit of Blood was almost as soon clear of them as Spirit of Wine; and when some Drops of it were let fall, they manifestly appeared less than Drops of Water. To discover the subtlety of the Parts of Human Blood, we so prepared common Water, by Infusions made in it without Heat, that by putting one single Drop of our Rectified Spirit of Human Blood into ten Ounces and four Scruples of the prepared Water, and lightly shaking the Viol, there appeared throughout the Liquor a manifest Colour, whereof no Degree was discernible before; so that it dispersed itself through a thousand times as much Water, and produced a manifest Change in the Colour of it: And tho' this Computation is made upon the common supposition that a Drop of Water weighs a Grain, yet tho' it weighs more a little, the Difference is recompensed, since having dropped ten Drops of common Water into a common Balance well adjusted, and having likewise dropped ten Drops of this Spirit, we found that the last were not only less in bulk, but lighter, since they weighed not above four Grains, so that the Proportion to which it extended itself, may be said to be as one, to betwixt 4000 and 5000; and this subtlety of the Parts of the Spirit of Human Blood will appear to be yet much greater, if we consider, that some Part even of this Drop must needs be Phlegm. TITLE VII. Of the Odour, Taste, Colour, and Transparency of the Spirit of Human Blood. THat the Spirit of Human Blood is in respect of some Liquors potentially Cold, since it refrigerates them, and with reference to others potentially Hot, since being mixed with them it renders them Hot, may appear from the following instance; for having put the lower end of an Hermetically sealed Weatherglass into a slender Cylindrical Glass, we poured as much moderately strong Spirit of Blood into it as covered the Ball, and then dropped on that Liquor some good Spirit of Salt, upon which ensued a conflict accompanied with a Noise, Bubbles, and Heat, which made the Spirit of Wine presently ascend above two Inches and a half; which Experiment seems to be the more remarkable, because several other Volatile Alkalies being mixed with Acids, produce a notable degree of coldness; and whereas I had several times found by Trial, that the Spirit of Verdigrease would, with Volatile Salt of Salarmoniack or Urine, produce a real coldness. This Spirit of Verdigrease being mixed in the small Cylindrical Glass, with Spirit of Blood moderately strong, not only produced a hissing Noise and store of Bubbles, but an actual Heat, upon which the Liquor in the Thermoscope ascended above an Inch and a half, tho' both the Liquors employed amounted not to above two spoonfuls. TITLE VIII. Of the dissolutive power of Spirit of Human Blood. THAT this Spirit is not only a good Medicine for several Diseases, but is also a good Menstruum, will appear from the following instances. And first, having poured Spirit of Human Blood upon Crude Copper, in about a quarter of an hour the Liquor was tinged blueish, which colour grew higher and higher, till in some hours it was deeply Ceruleous. And to this I shall add, that having dropped a drop or two of Spirit of Blood upon a piece of bright Copper, within about half a minute of an hour, the Verge of the moistened part of the Surface appeared blueish, and in a little time after, the rest of the wetted Part acquired a fine Azure. Having poured Spirit of Blood upon filings of Zinke or Spiltre, it presently began to work manifestly in the cold; and when assisted by a little Heat, it dissolved the Zinke briskly, and not without producing store of bubbles, being also a little discoloured by the operation of this Experiment. Having put a piece of clotted Blood, which had been exposed to the Air, into a slender Vial of clear Glass, and then poured on a little rectified Spirit of Human Blood, and shook the Glass a little, the blackness of the superficial part of the Blood presently disappeared, and became a florid Scarlet, and the Liquor was tinged with a fairer red, and from a succession of bubbles passing from time to time out of the cold into it, seemed to work somewhat like a Menstruum, but in a little time after the Blood was degenerated from its former colour to a little more dark one. But another clot of Blood, one side of which was red and the other black, being put into the Vial, and Spirit of Blood poured upon it, the red side had its colour improved, but the other continued black and dirty. And I once preserved twelve drachms of Blood in two of the Spirit of Blood, and found that twelve months after it remained fair and florid, and little less than totally fluid; and when the Vessel was opened there appeared little sign of Putrefaction, but only a small clot was fastened to the bottom, the rest passing readily through a strainer; so that the Spirit seemed to have a great embalming Virtue, since it was able to preserve six times its weight of a Body so apt to putrefy: But to what hath been observed, I shall add, that having commited the Mixture to Distillation, the first Liquor was a kind of Phlegm, which was succeeded by a Spirituous Liquor and Volatile Salt in a dry form. Having poured some of our Spirit upon filings of Iron, where they were not in the least Rusty, and kept them together a while in digestion, we found, as we expected, that that Liquor by working upon them had produced a light substance, something paler than a Crocus, and there appeared likewise in the Liquor good store of thin Plates, which after a gentle Agitation, being held against the Sunbeams, exhibited the colours of the Rainbow very vividly; but the taste of the Liquor appeared not at all Martial. TITLE IX. Of the Tincture that may be drawn with Spirit of Human Blood. SPirit of Blood being put upon Saffron presently acquired a yellow colour; and from Tu merick, a Tincture like a solution of Gold, which may doubtless prove a good Medicine in the Jaundice; and some of this Spirit being put upon powder of Blood, it presently extracted from it a colour as red as that of French Claret, but when I made use of another parcel of Spirit well rectified, I found that it extracted not a Tincture so soon; and after several hours the colour it obtained was brown, which in some hours after was heightened into redness, and in a longer time it became almost as red as the former Tincture. To show that Spirit of Human Blood may extract Tinctures out of the hardest Bodies, we put filings with it into a small Egg, and kept them all night in digestion in a moderate Heat; and the next day we found the Liquor tinged with a deep brownish red; and those filings which stuck to the sides of the Vessel and were above the Liquor, were turned by the Exhalations of this Spirit into a yellow Crocus: But the Mixture being kept some days longer in the same Vessel, the colour of it was grown Opacous, and appeared to be black when it was looked upon in a considerable bulk; but it seemed of another colour when looked upon as it was spread thin upon white Paper. Some of this Tincture being poured upon an infusion of Galls, it would not make it of an Inky colour, nor was the precipitate, which presently fell to the bottom, of an Inky colour. From which Experiments it appears, that it is unsafe either to suppose, that if Chalybeates be dissolved in the Body, it must be by some Acid Juice, or to conclude, that if Steel be dissolved by the Liquors of our Bodies, they must be ex predominio Alkalizate, since a Liquor that is very different from Acids dissolves it; but without touching further upon this account, I shall rather commend it to the consideration of Physicians, to pitch upon some other method of explicating the effects of Chalybeates upon Human Bodies, and whether martial Medicines may not be made use of, which are prepared by Volatite Alkalies, instead of Acids. Spirit of Human Blood being kept in digestion with powder of Amber, it extracted no considerable Tincture, but whether the fault was in the fineness of the Amber, or the weakness of the Spirit, I shall leave undetermined. Some Spirit of Human Blood being put upon some of that Gum called Seed-Lac soon became tinged, which I supposed to proceed from a superficial colour of some Parts of the Gum, proceeding from some adhering Blood of the little winged infects, who by their bitings occasioned this Gum, upon the twigs of the Trees where it is found; so that the colour seems not to be given by the Gum, but the Blood of those Animals, and may probably be a good solvent Medicine, since most of the infects used in Physic consists of Parts very subtle and penetrating, and of considerable Efficacy. TITLE X. Of the Coagulating power of the Spirit of Human Blood. HIghly rectified Spirit of Human Blood, being well mingled by shakeing it with a convenient quantity of Urinous Spirits, there will presently ensue a Coagulation or a concretion of Parts, either of the whole Mixture or a Portion of it, into corpuscles of a Saline form, which cohering loosely together make up a mass of a fluid and consistent soft temper; in which form it will continue in a cool place several months. TITLE XI. Of the Precipitating power of Spirit of Human Blood. IT hath a power of Precipitating, as other Volatile Spirits, most Bodies dissolved in Acid Menstruums; I say most, because there is no need this rule should be general, or hold when the Body is of such a Nature, that it may be as well dissolved by an Acid as an Alkaly; and that there are such Bodies appears, since Spirit of Human Blood will dissolve both Copper and Zink, which may be likewise dissolved by Aqua Fortis and other Acid Menstruums. But that this Spirit will precipitate other Bodies dissolved in Acid Menstruums, I am convinced by several trials made on red Lead dissolved in Vinegar, Silver in Aqua Fortis, Gold in Aqua Regia, and Tin dissolved in an appropriated Menstruum, and several other Bodies. And out of a Solution of common Salt made in Water, we could readily precipitate with the Spirit of Blood, a Substance which looked like a white Earth, and such a Substance I obtained in a far greater quantity, from that which the Saltmakers call Bittern, which usually remains in their Salt Pans, when they have taken out about as much Salt, as would coagulate in figured grains. This Spirit of Human Blood does likewise precipitate a Solution of Dantzik Vitriol in Water, but that Solution is not a total one. TITLE XII. Of the Affinity between Spirit of Human Blood, and some Chemical Oils and Vinous Spirits. THAT there is an Affinity betwixt Spirit of Human Blood, and Spirit of Wine, appears, since we have formerly observed that being put together, they will concoagulate, and continue united a long time; and tho' a rectified Spirit of Wine will not draw a Tincture from Blood, yet Spirit of Blood will. But as for Lixiviate Liquors such as are made of Salt of Tartar, fixed Nitre, etc. we find not that they will strictly associate with it. Spirit of Blood readily mixes with that Adiaphorous Spirit formerly mentioned; but dephlegmed Spirit of Blood mixed by agitation with its Oil, will presently separate again, tho' with Spirit of Wine it will permanently unite, though these two Liquors belong to a different, viz. the one to the Animal, and the other to the Vegetable Kingdom. With the essential Oils of Aromatic Vegetables, the Spirit seems to have a greater Affinity; for an equal proportion of this Liquor, and of Oil of Aniseeds, drawn in an Alembick per Vesicam, being shaken together, they made a soft or Semifluid coagulation, which continued in that form for a day or two; and would probably have longer done so, if I had not had occasion to proceed further with it. To show that Spirit of Human Blood may either communicate some of its saline Parts to essential Oils, or work a change in them; I digested a while in a Glass with a long neck some recstified Spirit of Human Blood, with a convenient quantity of Oil of Aniseeds drawn in an Alembick, and found that the Oil grew coloured of a high yellow, and afterwards attained a high redness; which may afford us a hint of the cause of some changes of colour, that are produced in the Liquors of the Body. To take off the stinking quality of Human Blood, and to render it more grateful, we mixed with it in a Glass about an equal quantity or half as much Oil of Aniseeds, and having shaken them together in the Glass, we placed it in a Furnace with a gentle Heat, by which means the slight Texture of the Coagulum being dissolved, part of the Oil appeared floating upon the top, whence being separated by a Tunnel, the Liquor was whitish and without a stinking smell; it smelling and tasteing strong of Aniseeds, tho' the saline Particles retained a considerable degree of their brisk and penetrating taste. Another way I took to deprive Spirit of Human Blood of its offensive smell was, by employing a Medium to unite it with essential Oils; for having dissolved an eighth part of Oil of Aniseeds in highly rectified Spirit of Wine, and added an equal quantity of Spirit of Human Blood, and upon a convenient agitation we suffered the Mixture to settle a considerable time, after that it appeared, that some of the Oil swum in drops distinct from the other Liquors, which consisted of a Mixture of the two Spirits impregnated with a few particles of Oil which they had detained. This Liquor abounded with little Concretions made by the Coagulation of the Sanguineous and Vinous Spirits; which by a gentle Heat were sublimed in the form of a Volatile Salt, to the upper Part of the Glass; and this Salt had not only a much less penetrating Odour, than the mere Volatile Salt of Human Blood, but had quite lost its stink, and yet retained a considerable quickness, and something of the scent of Aniseeds; and the remaining Liquor was likewise deprived of its ill smell, and moderately imbued with that of the Oil. To try whether there would be any Affinity between our Spirit, and the highly rectified Oil of Petroleum, I shaked a convenient quantity of them together in a new Vial, upon which they presently turned into a white Mixture; and tho' after a few hours the greater part of the Oil swum above the Spirit, yet there appeared betwixt the two Liquors a good quantity of whiteish Matter, which seemed to be produced by the Union of many Particles of the Spirit and Oil, which were most disposed to combine. TITLE XIII. Of the Relation betwixt Spirit of Human Blood and the Air. TO try whether the Air will have any considerable effect on the Spirit of Human Blood after Distillation, as it evidently hath on the Blood before, I spread thinly upon a piece of white Paper some small filings of Copper, and wetting them well without covering them quite over, with a few drops of Blood; by that means they being well exposed to the free Air; the Action of the Liquor was so much promoted, that within a minute or two it did even in the cold acquire a blueish colour; and in fewer minutes than one would have expected, that colour was so heightened as to become Ceruleous; but another parcel of the same filings being put into a Vial, the intercourse of the Air being excluded, the Liquor would not in some hours acquire so deep a colour. Having in a clear Cylindrical Vial of about an Inch Diameter, put more filings of Copper than was requisite to cover the bottom, and poured so much Spirit of Blood upon them as wrought about a finger's breadth above them, it in a few hours acquired a rich colour, which after a day or two began to grow more faint, and afterwards gradually declined, till it was almost lost; yet the Liquor was not altogether limpid or colourless, as I have often had it with Spirit of Urine or Salarmoniack, and these remains of blueishness I attributed to the effects of the Air included in the Bottle, with so small a quantity of Liquor. And tho' I thought it not impossible, but that length of time might destroy its blueishness, yet unstopping the Vessel, I observed, that in two minutes of an hour, the Surface of the Liquor where it touched the fresh Air became Ceruleous; and in a quarter of an hour the whole Body of the Liquor had attained a deeper colour than that of the sky, which colour grew sensibly paler again when the Vial was stopped: But one thing I must add is, that I have found the Experiment to succeed with some Analogy, when another Volatile Spirit hath been made use of, in which there was no Volatile Salt of Human Blood; but the Experiment being repeated the Air produced a green and not a Ceruleous colour, which makes me suspend my Judgement till satisfied by further experience, whether the event of the former trial depended on any Affinity of the Spirit with Blood or not. And here I shall add, that a parcel of Spirit of Human Blood being kept in Vacuo Byliano, when the Air was pumped out, it afforded fewer and less bubbles than an equal quantity of common Water. TITLE XIV. Of the Hostility of the Spirit of Human Blood with Acids, whether they be in the form of Liquors or Fumes. IT exercises its Hostility against more than one sort of Acid Spirits, as Spirit of Salt, of Nitre, Spirit and Oil of Vitriol, Aqua Fortis, Aqua Regis, etc. And not only against Facitious but natural ones, as the Juice of Lemons, upon its Mixture with which there presently ensued a great commotion with noise. But there is not only an Hostility evident betwixt the Parts of these Liquors, but also their Effluvia; for if Spirit of Salt of Nitre be put into a Vial somewhat wide mouthed, and Spirit of Blood rectified into another, when these Liquors are held near one another, their invisible Emanations joining together will form a manifest Smoke. Some pure Volatile Salt of Human Blood being just satiated with Spirit of Nitre, we slowly evaporated the superfluous moisture, which being done, we took the compound Crystals which the Mixture afforded, and put it into a Bolt-Head with a slender and a long neck, and then adding to it a convenient quantity of Salt of Tartar, and as much distilled Water as made the Mixture Liquid enough, the Salt of Tartar detained the Spirit of Nitre, and a good proportion of the Volatile Salt ascended in a dry form to the neck of the Vessel. Spirit of Blood and Nitre being mixed together, there ensued a conflict, in which thick white fumes risen plentifully, and circulating in the Vessel, ran down the sides of it in a white stream; until the fumes ceased to rise again, the Mixture in the mean time appearing reddish. Being settled and seeming to have been so discoloured by a fattish Substance, we put to it a little rain Water, and having by filtration separated the Faeces, and slowly evaporated the thus clarified Liquor, the saline Parts shot into Crystals like those of Salt-Petre; but after a while seemed yellow, as if tinged with the Oil. N. Tho' on several occasions the Spirit of Blood appears Oily, yet I not long since dissolved another parcel of Blood, whose Liquor was clear and limpid a year after. Some of the before mentioned Crystals being put upon well kindled Charcoal, presently melted and burnt away like Salt-Petre, but the flame seemed not so halituous, and differed in colour, being not at all blue but yellow; and after the Deflagration ceased, there remained upon the Coal a lump of dirty coloured matter, which had scarce any taste, nor was that little it had Alkalious. This brittle Substance being held in the flame, became red hot without any sensible imminution, and so it did upon a live Coal. TITLE XV. Of the Medicinal Virtues of Spirit of Human Blood outwardly applied. SINCE we meet not with any Acid Substance, except in the Pancreatic Juice of a sound Person: And since the fixed Salt of Blood does much resemble Sea-salt, whether its Spirit be Acid or no; and since several Parts of the Body whether Solid or Liquid, afford a Liquor impregnated with store of Volatile Salt; it is not amiss to think that the Spirit of Human Blood, may have considerable effects in several Diseases, even when externally applied. And that Spirit of Salarmoniack hath been found successful in assisting several People in Apoplexies, Epilepsies, etc. when applied to or put up the Nostrils, it's confirmed by the experience of several learned and able Physicians; and upon the like reason I prepared a Volatile Salt sublimed from a compound Salt, obtained from Spirit of Blood satiated with Nitre. And for a like purpose, to bring over the Saline Part of Blood in a liquid form, we mixed two Parts of dried Blood with three of Spirit of Blood, and distilling them with a pretty strong fire, we obtained a pretty deal of Spirit, unaccompanyed with any Volatile Salt, in a dry form; and this Spirit seemed to have a stronger taste and smell before rectification, than Spirit of Human Blood prepared another way had after rectification; and had we made use of more Lime, I question not but that we should have obtained a more piercing Spirit, since it would have retained more of the Oil and the superfluous moisture. And on this occasion I shall add, that I have often found headaches cured by the separated application of Spirit of Human Blood; which is likewise good in Hysterick and Hypochondriacal Cases, and in fainting Fits; and if the smell of it makes it too nauseous, that may be corrected according to the method already laid down in this Chapter, to which I shall add, that a few drops of Oil of Rhodium, being dissolved in Alcohol of Wine, if that be mixed with Spirit of Human Blood, it will give it a very grateful and odoriferous smell. And here I shall add, that Medicines made of Amber have been found successful not only in Convulsions, and other Distempers of the Genus Nervosum, but the Tincture of it in Spirit of Wine, hath proved successful enough in Diseases both of Men and Women. And this Tincture may not inconveniently or unsuccessfully be added, to correct the Odour and increase the Virtues of Spirit of Human Blood; and though Oil of Amber will not mix readily with Spirit of Wine, yet if they be shaken together and left to settle at leisure, tho' they settle in distinct masses, yet the Spirit would even in the cold extract a high and a yellow Tincture, little different from the Oil itself, which may be mixed with the Spirit of Blood, till the smell of the Amber be predominant. To what hath been said of the external use of Spirit of Human Blood I shall add, that if the Oil in these Mixtures should be too much predominant, it may be easily separated by running it through a Tunnel, whose Orifice at the bottom is form so small and sharp, as to give way for the Spirit to run off first, which may when thus separated be kept in a distinct Vessel. And since if the Vinous Spirit be sufficiently rectified, there will by the Coagulation of the Saline and Urinous Parts, be produced a kind of Salt, you may either pour the Liquid part into another Vessel, and then use them separate, or else separate the Salt by sublimation in a dry form; and Spirit of Human Blood thus separated will have a fragrant brisk and piercing Odour. But, To conclude, this Spirit is not only good in respect of the Virtues ascribed to its scent, but it may be good likewise when used as a fomentation, as Spirit of Salarmoniack hath been effectual in removing the Pains of the Gout, and in the Erisipelas. And since upon the account of its Alkalizate Nature it may be good to correct Acidities, it may be for that purpose made use of both by Physicians and Surgeons. TITLE XVI. Of the Medicinal Virtues of Spirit of Human Blood inwardly used. I Have been long apt to think, that the same peccant matter may produce several Distempers as its effects are diversified, partly by its greater or lesser quantities, as well as more or less active qualities, and partly by the particular Natures, or Structures, and Situations of the Parts that it invades; which seems to be favoured by the frequent Metastases of Morbific matter in several Distempers, since the same Acid or sharp Humours sometimes occasion a Colic, sometimes after that a Palsy, at other times a Cough, a flux of the Belly, an Opthalmia, a Violent Headache, Convulsions, etc. As the peccant Humour falls upon this or that part, upon which account one or two Medicines may be able to cure several Distempers, especially if endued with any variety of active Virtues; and upon these grounds I am inclined to believe, that the Spirit of Human Blood may be a good Remedy in several internal affections of the Body; and indeed Volatile Alkalies in general have been so prosperously made use of in Physic, since the year 1656 as to invite several Physicians to employ them instead of other Medicines, which clog and weaken the Patient, and want several advantageous qualities, which may be found in Volatile Alkalies. And indeed Spirit of Human Blood mortifies Acid Salts, which occasion several Diseases: It is likewise a great Resolvent, and fit to open Obstructions which produce not a few Diseases; it is also Diaphoretic and Diuretic, and able to discharge several noxious Salts, and to expel several Malignant and Contagious Particles of matter. It resists Putrefaction and Coagulation; and gives a briskness and Spirituousness to the Blood, which promotes free Circulation, upon which account it is a good Cordial and an Antidote against some Poisons: It is very friendly to the Genus Nervosum, and to cure its Distempers, and Balsamic in some sort of Asthams, it neither causes great evacuations, nor does it clog the Stomach; or is disadvantageous in any manifest qualities. And it may likewise be very good in such cases as Spirit of Salarmoniack hath been found successful in. Helmont commends it in Epilepsies, which he says, it will cure in Adult Persons: And I have known it cure an inveterate Consumptive Cough, and a very bad Headache, which had a long time baffled very eminent Physicians. But besides the Virtues it hath when simply used, its Virtues may be ennobled and diversified by a long digestion, or frequent Cohobations of the Spirit with the Oils, Salt or Phlegm of the same Concrete; or, by uniting it with Acids, as Spirit of Nitre, or Vinegar; Verdigrease, Oil of Vitriol, etc. either used in a Liquid form, or when reduced by evaporation into Crystals. Or the Virtues of it may be ennobled, by uniting our Spirit with Metalline Solutions, as of Gold, Silver, or Mercury; and with Solutions of Minium made with Spirit of Vinegar; by a Mixture of which Liquor and a slow evaporation of them, I have obtained finely shaped Crystals. Or, again either by uniting with it Sulphur opened with Salt of Tartar; or by dissolving in it Metalline Bodies, as Copper, Zinke, and Iron. Or by adding about a double weight of Alcohol of Wine; for these Liquors being shaken together, will in a very great measure coagulate into a Salt, which will retain a considerable degree of quickness and penetrancy. And why such Salts as these should not be efficacious I see no reason, since such a kind of a Mixture, tho' made with another Urinous Spirit hath had extraordinary effects in Fevers. nor is the Liquor this Salt leaves behind useless in Medicine when well dephlegmed. But this Spirit may be rendered still more commodious, if impregnated with essential Oils; and by that means several Oily Volatile Salts may be produced, which may be useful in peculiar Distempers, as those Oils respect this or that part in their Medicinal Virtues. CHAP. X. An Appendix to the Memoirs for the Natural History of Human Blood: Containing, first, particulars referable to the second Part of the foregoing History. EXPERIMENT I. HAving caused twelve Ounces of dried Blood to be carefully distilled, the Substances obtained from it, were of Volatile Salt and Spirit together five Ounces; the Liquor poured off from the wet Salt being thirteen Drachms, fifty four Grains, so that the Salt was three Ounces, two Drachms, and six Grains; of fetid Oil there were two Ounces; of Caput Mortuum four Ounces, and two Drachms; so that about six Drachms of the whole was consumed in the Operation. The Caput Mortuum being calcined yielded but six Drachms and a half of ashes, the fixed Oleaginous Parts being consumed by the accension; the colour of the ashes was reddish when cool, tho' in the fire they appeared white as soon as the Oil was consumed, these ashes being turned into a Lixivium, afforded five scruples of white fixed Salt, besides a little which got into the contiguous Sand, which being recovered by Water, and reduced to a Salt made a scruple more. So that there remained for the Terra Damnata fourteen Scruples and a half, which is a good deal above twice the weight of the Salt; whence it appears, that the pure fixed Salt is but between the fifty seventh and fifty eighth part of dried Blood, and therefore probably amounts to no more than about the 170th part of the mass of Blood; and the fixed Earth is to dried Blood as about nineteen and about a half to one. EXPERIMENT II. A parcel of Blood weighing ten Ounces and seventy three Grains, being slowly distilled to dryness in a Head and Body on a digestive Furnace, afforded of Phlegmatic Liquor seven Ounces, two Drachms, and forty seven Grains; and of Caput Mortuum or dry Substance two Ounces, two Drachms. This pulverable matter being distilled in a Retort by degrees of fire yielded two Drachms, forty eight Grains of Oil. The Spirit being poured off, the Salt weighed but forty eight Grains, and the Salt being washed out with the distilled Water, we obtained thence by Sublimation into the neck of a Glass-Egg one Drachm, five Grains of dry Salt. The Caput Mortuum weighed six Drachms, twelve Grains, which being carefully calcined yielded two Scruples and four Grains of ashes; which were red, and these being elixivated afforded eighteen Grains of Salt, besides the remaining Earth, which is of a red colour with an Eye of Purple, Particulars referrable to the Primary Title of the Natural History of Human Blood. EXPERIMENT I. Spirit of Vinegar put upon Blood, turned its red colour of a dark or dirty colour. EXPERIMENT II. Juice of Lemons poured upon the superficies of Blood, impaired its florid colour. EXPERIMENT III. Juice of Oranges changed Blood less than Lemons. EXPERIMENT IU. The black part of clotted Blood exposed to the Air, presently became of a pleasant and florid colour. EXPERIMENT V. Spirit of Salarmoniack dropped upon black clotted Blood, presently rendered it florid, but not so much as the open Air. EXPERIMENT VI. Fixed Alkalies or lixiviate Salts resolved per Deliquium, turned it red, but not so florid as the Urinous Spirit. EXPERIMENT VII. The Juice of Scurvy Grass fresh drawn, inclined the black Surface of clotted Blood to redishness. EXPERIMENT VIII. Blood being closed up with an eighth or fourth part of Spirit of Wine about three years, was coagulated, but neither stank nor was it in the least putrified. EXPERIMENT IX. A small piece of concreted Blood being left three days in Spirit of Wine, was rendered moderately hard and friable throughout. EXPERIMENT X. Upon trial we found, that an Ounce of distilled Water would dissolve at least two Drachms of Volatile Salt of Human Blood; and by the help of Heat it was able to dissolve twenty five Grains more, nor did any of this Salt shoot into Crystals upon its Refrigeration. EXPERIMENT XI. The aforementioned Solution being put into a Retort, to be drawn off with a pretty quick heat, we obtained a distilled Liquor, that contained almost all the Volatile Salt, except a little which escaped in a dry form; and this Liquor being as strong as moderate Spirit of Human Blood, it may give us a hint, what proportion of a Liquor to Salt may be sufficient for such a Spirit. And one thing here may be worthy our notice, viz. That the Liquor which was too much impregnated with Salt, having been exposed to the Air in a frosty Night, we perceived at the bottom of the Glass a good deal of Volatile Salt shot into Crystals, tho' the Crystals that were this way obtained were fine and clear, and some of them larger than Spangles; yet being very numerous and sticking together, we could not discover the shape of particular Grains, nor whether they were all of the same shape, but divers of them appeared to be flat thin Plates, with fine rectilinear Angles, so that we conjectured if the whole Plates could have been seen, their broadest Surface would have been found Hexagonal, or of some Polygone figures very near of kin to that. EXPERIMENT XII. An Ounce of distilled Water was shut up in a Glass-Egg, with as much Salt as could be dissolved in it, and exposed to congeal in a frosty Night; but the Salt was neither congealed nor the Water, tho' afterwards it was removed into a frigorifick Mixture, which would perhaps have froze Beer, or Ale, or the weaker sort of French Wine; yet we did not perceive the least Glaciation. EXPERIMENT XIII. Tho' Sea-Salt dissolved in Water renders it less subject to be froze, yet being joined with Ice or Snow, and externally applied, it conduces to the freezing of it. Wherefore we mixed about a Scruple of Salt of Human Blood with Ice, to try whether it would have the like effect, and accordinly we found, that a slender Pipe of Water being immersed in it, the Water in the bottom of the Pipe was froze. EXPERIMENT XIV. Some of the fibrous part of Human Blood, being exposed to the Air in an open and shallow Glass in a frosty Night, the next Morning it was lightly frozen, and the Surface of the Ice prettily figured with resemblances of Combs with Teeth on both sides, not much unlike Salarmoniack coagulated in common Water. And not here to mention what hath been said, by some, of the Virtues of Human Blood, I shall propose a couple of Medicines to be prepared from it, one of which may perhaps have no inconsiderable effects: The first Medicine I attempted to make, was by putting to Salt of Tartar Oil of Human Blood instead of Oil of Turpentine, and by stirring them long together in the open Air, to make such a saponary concretion as Matthew's Corector, which is esteemed and employed with good success by some London Physicians. The other Medicine I endeavoured to make, was by uniting by long digestion the Salt, Spirit, and Oil of Human Blood into a Mixture, which some Chemists call a Clyssus. Particulars referrable to the third Part of the History. EXPERIMENT I. THE Blood of a young Man, when cool, having its Serum and fibrous Parts separately weighed, the latter weighed about six Ounces, and the serous part not many Drachms from that weight. EXPERIMENT II. The very ingenious Mr. Hook and myself, having often observed on the Surface of frozen Urine, figures which much resemble Combs or Feathers; considering the Affinity usually agreed on betwixt the Serum of Human Blood and Urine, we exposed some of it, strained through a linen rag to separate the Grumous part, to the Air, in a shallow Vessel several Nights consecutively, and observed, that being froze, there appeared upon the Ice contiguous to the Air, certain figures which did not ill resemble those of conglaciated Urine. EXPERIMENT III To try whether Serum as well as Urine, might not as well be made use of for invisible Ink, we traced some Characters with it upon white Paper; and when they were dried, we held the unwritten side over the flame of a Candle, keeping it always stirring, that it might not take fire, upon which the Letters on the upper side appeared of a dark colour, tho' not of an Inky blackness. Particulars referrable to the fourth Part of the History. SINCE according to the several ways of distilling Human Blood, the Spirit of Salt, etc. produced, may be considerably diversified; I distilled three Portions of Human Blood, each with a different additament. The first which was distilled with Quicklime, we shall subjoin the following account of, viz. Four Ounces of coagulated Blood, being mixed with an equal proportion of Quicklime, we distilled them by degrees of fire in a Retort placed in Sand, by which means we obtained a proportion of reddish Spirituous Liquor, which seemed not very Phlegmatic, together with some Oil, the quantity of which was but small, the rest being probably detained by the Lime, and a small Portion of that little Oil that came over sunk in the Spirit, the rest swimming upon it. The Spirit being set in a digestive Furnace in a small Head and Body, to rectify with a gentle Heat, the Receiver was three or four times removed; and we observed, that the first Spirit that came over was not near so fetid, as that which ascends when it is distilled per se; and the like was observed in the succeeding Portions, the Oil being detained behind by the Quicklime; the rectified Spirit was clear and colourless, and had a taste much stronger than its smell, and so strong that it made me think some Volatile Alkalious Parts of the Quicklime were carried up with it, to be satisfied of which we dropped some of it upon a Solution of Sublimate with fair Water; and on the first contact we perceived a precipitate a little inclining to yellow, as Quicklime in a greater quantity usually turned it: But afterwards the Precipitate appeared white, like that made with ordinary Volatile Liquors of an Urinous Nature. Some of this Spirit put into a Glass-Egg, afforded not any Volatile Salt in a dry form, and the trial being continued, we found, that the Spirit by the action of the fire lost its limpidness, and became muddy or troubled. Another Portion of it being mixed with a highly rectified ardent Spirit, upon their being kept all Night in the cold, no coagulation ensued, nor could we perceive any, when it had been kept several hours in a moderate Heat. But the Mixture acquired a yellow colour, and let fall a pretty deal of darkish powder. Some of this Spirit being mixed with good Spirit of Salt, they smoked at their first meeting, but produced neither bubbles or noise. Another Portion being mixed with Oil of Vitriol, there was produced a great smoke, and an intense degree of Heat without any visible Ebullition, or any bubbles or noise, but the colour of the Oil was heightened and grew almost red. From whence it appears, that this Alkalizated Spirit of Blood is very different from simple Spirit of Blood; but whether upon this account it becomes a more violent, or a less safe Medicine, further Experience must discover. EXPERIMENT II. Two Ounces of Tartar calcined to whiteness by an equal weight of Nitre, being distilled in a Retort in a Sand Furnace, with an equal weight of dried and powdered Blood, it appeared that Quicklime acts on this occasion otherwise on Blood than other Alkalies do; for whereas the Blood distilled with that yielded a strong Spirit before rectification, and unaccompanyed with dry Salt; this Mixture afforded us at the first Distillation a weaker Spirit, but so much Volatile Salt with it as covered the whole internal Surface of the Receiver. Besides there was a manifest difference in their Caput Mortuums: And tho' the Spirit drawn from Quicklime did not ferment with Acids, yet this Salt upon an affusion of Spirit of Salt would. EXPERIMENT III. An equal quantity of the powder of Human Blood and Oil of Vitriol being mixed together, in a little time they grew warm; and then placing the Retort in a Sand Furnace, by degrees of fire we obtained a Spirit, which was preceded by a good deal of Phlegmatic Liquor of an odd Sulphureous smell, and very strong and lasting. The Caput Mortuum seemed to be of a very compounded Nature. But one thing observable in our Experiment was, that tho' Oil of Vitriol usually exercises a fixative Power, on many Bodies wherewith it is mixed in Distillation, yet this Experiment afforded us a pretty quantity of Volatile matter in the form of a white Salt, but of an uncommon smell and taste. EXPERIMENT IU. We prepared an Aurum Fulminans, by precipitating a Solution of Gold made in Aqua Regia with Spirit of Human Blood, and by dulcifying the precipitate with common Water, and then drying it leisurely. EXPERIMENT V. Having immersed the Ball of a Weatherglass in Spirit of Blood contained in a wide mouthed Glass, we poured on some Spirit of Verdigrease, which made a conflict with it and excited bubbles; there was likewise produced a degree of warmth not insensible on the outside of the Glass; and the Liquor was raised in the Thermoscope a considerable height, tho' when the conflict was over it began moderately to subside again. EXPERIMENT VI. Having gradually mixed Spirit of Blood, with as much Spirit of Nitre as it would work on it, they produced bubbles with a considerable noise, and when the Liquors had settled in a cool place, it appeared, that an Oil had been separated from it in this operation; since a red colour was not only produced by it, but the Surface of the Liquor was covered with such a film, as Liquors copiously impregnated with Antimony or other sulphureous Bodies usually are. And when it was looked upon with Eyes conveniently placed in reference to it and the Light, it appeared to be adorned with vivid colours of a Rainbow, as Red, Yellow, Blue, and Green; and that too in their natural order. EXPERIMENT VII. Spirit of Human Blood which had been kept twelve years, being when it was looked upon not well stopped, it appeared to be a Spiritless Phlegm, but not of a red florid colour, and but little wasted. EXPERIMENE VIII. Spirit of Human Blood being exposed to the Air in a frosty Night, in which Oil of Vitriol was froze, it was not in the least altered or coagulated by it, but being put into a frigorifick Mixture, it was presently frozen. EXPERIMENT IX. A piece of black clotted Blood, being put into Spirit of Human Blood, it became of a florid colour, and retained that all Night. EXPERIMENT X. Spirit of Blood being poured upon powdered Blood, presently dissolved part of it, and acquired a deep pleasant colour. But Spirit of Wine being poured upon another parcel, acquired not a Tincture, till urged with Heat; and then only a yellow one; but common Water presently dissolved a pretty deal of another parcel. EXPERIMENT XI. Spirit of Human Blood poured on lumps of Vitriol, dissolved them slowly without a froth; but upon the powder the solution was quicker and with a froth. And both the Solutions were of a more lovely blue than the Mineral itself; nor was there a dark Precipitate as in a Mixture of ordinary Vitriol and Spirit of Urine. EXPERIMENT XII. Spirit of Human Blood employed for an invisible Ink, is much better than Serum of Blood. EXPERIMENT XIII. Having immersed the Ball of a Weatherglass in distilled Water contained in a wide mouthed Glass, upon an affusion of two or three spoonfuls of Spirit of Human Blood, the tinged Spirit of Wine did presently subside in the Stem, within a little, as I have observed it with Spirit of Urine. And here it may not be amiss to take notice, that the reason why I employ distilled Water instead of common Water or Pump Water, is, because it is not impregnated with Salts, which may vary the success of the Experiment. EXPERIMENT XIV. Spirit of Blood being poured upon filings of Copper, and stopped up in a Glass extracted a Ceruleous Tincture, which in a few days gradually growing fainter, I opened the Glass upon which its Ceruleous colour was renewed, and extended itself downwards towards the bottom of the Vial, and so strong as to render the Liquor almost Opacous. And tho' the Liquor was stopped up several days after, yet it lost not its colour. EXPERIMENT XV. Some of the same Spirit being poured upon Lapis Armenus, extracted from it a lovely and a deep blue, almost like a Solution of filings of crude Copper in the same Menstruum. Postscript To conclude this Chapter I shall add, that tho' I have laid down these notes with what exactness was possible, yet I question not, but that the Blood of several, and even of the same Animals is so different at different times, that were they to be tried over again they would scarce have the same effects; yet it will not be a just reason to discourage others in further Trials, since the advantage natural knowledge may attain by it, will be a sufficient reward. CHAP. XI. Of the Reconcileableness of Specific Medicines, to the Corpuscular Philosophy. Of specific Medicines. BEfore I descend to show that the notion of Specific Medicines is agreeable to specific Medicines, I shall first represent, that I am induced to believe that there are such, by the common Observations of a great many learned Men and able Physicians; and to favour this common Observation, viz. That there are such Substances which have peculiar effects, which can be ascribed to no manifest Qualities, I shall urge the effects of Poisons taken in a very inconsiderable quantity. And I am told, that something that fell from a Spider into a Man's Eye caused him to lose his sight, to which I shall add, that Spiders are observed to kill flies, much sooner than cutting off their Heads, or running them through with Pins will do it. To which instances we may add, that most Poisons are cured by appropriated Antidotes; and as perfumes cause ill symtoms in many Histerick Women, so the fumes of Feathers burned relieve them. And I have found that the smell of Spirit of Hartshorn or Salarmoniack, hath recovered People made sick by fragrant Odours. But beyond all other Arguments is experience; for Galen tells us, That the ashes of a Craw-Fish will cure the biting of a mad Dog, and that their effects are much more considerable, if to ten Parts of Craw-Fish we add five of Gentian and one of Frankincense. And Diascorides commends them against the same Disease that the Pergamenian does. And tho' the stings of Scorpions usually produce very acute Pains and formidable Symtoms, yet the mischief is easily remedied, either by crushing the Body of the Scorpion upon the Hurt, or by anointing the Part with Oil of Scorpions, tho' the Liquor appears not to have any sensible Qualities, to which their Efficacy may be ascribed. And to these Instances I might add, that Verginian Snake-weed cures the sting of a rattle Snake, and the Jesuits Powder is a specific in Agues. And tho' it be argued against the Virtues of specific Medicines, that they are altered by the ferment of the Stomach, and other strainers of different Textures, and that a great deal is carried off by Excrements, or is assimilated and converted into the Substance of our Bodies; yet to these things it may be answered, that not only Ointments, Plasters, Periapta, etc. work upon the mass of Humours; but even those Medicines which are allowed to work by manifest Qualities, perform what they do upon the account of their Particles alterering, and differently disposing the Humours of our Bodies, and in doing of that they are liable to the same objections offered against specific Medicines. Besides, it is observable that Rhubarb, will tinge the Urine of those that take a considerable Dose. And there is a Fruit called prickled Pears in the English American Colonies, which passes by Urine, so much unaltered, that the People think, when strangers to it, that they piss Blood. And Elaterium so much impregnates the Milk of a Nurse, that it will Purge the Child that takes it. And I remember that in the confines of Savoy and Switzerland, when the Cattle fed on a Herb called wild Garlic, the butter would sensibly taste of it. And in Ireland they have a kind of Seafowl which feed upon Fishes, which is so little altered, as to make some question whether it be Flesh or Fish. And tho' it be further urged against Specific Medicines, that so little is dispersed through the habit of the Body, that it can have no considerable effects; yet their Efficacy may answer for their smallness in quantity. For I am told that the Negroes have a Poison, which tho' it work slow, is nevertheless Mortal, and this they conceal under the Nails of their Fingers, and drop into the Aliment of those they have spite to. And I know a Vegetable Substance, half a Grain of which will be too violent a Purgative; and sometimes Mortal: And tho' English Vipers are looked upon as no Poison, yet by the Wound of a single Tooth I knew one who was taken with violent Vomitings. To which may be added the terrible effects of Scorpions in the Island of Java. And we see that several Women, otherwise strong and lusty, will fall into Swoons upon the smell of Musk or Civet, tho' all the Effluvia that affect them, would not amount to the hundredth part of a Grain; and by Effluvia, perhaps not more plentiful these Symptoms may be again removed. And the Portions of Crocus Metallorum in Wine, or of Quicksilver in Water, tho' small have very considerable effects, so that when a Child who obstinately refused all Medicines, drank small Beer impregnated with Mercury, he was much relieved in a violent worm Fever. That their Operations may be Mechanically solved, is proved in the following Propositions. Having said thus much of specific Medicines, I shall now proceed to lay down some things in the following Propositions, to show that they be mechanically explicated: But first I shall premise, that I would not have the Body to be considered as a dull lump of matter, but as an admirably contrived Mechanical Engine, consisting of Parts tightly contrived and adapted to their particular Uses; and that the effects of Bodies upon it may be considered in reference to that Disposition of their Parts. This being premised there is no need to think, that all specificks act after the same manner, or the same way, and sometimes the specific may operate by a joint and in a compound way. But to proceed to the following Propositions. PROP. I. Prop. I. Sometimes the specific Medicine may cure by discussing or resolving the Morbific matter, and thereby making it fit for Expulsion by the greater common shores of the Body, and the Pores of the Skin. Thus the Blood impregnated with Medicinal Particles, may act upon gross Humours which obstruct the Parts, and are not to be resolved without specific Solvents, which by their figure and agitation may get in betwixt and separate those Viscous Parts; so Blood impregnated with Salarmoniack dissolves Copper, not by manifest Qualities; but by Virtue of the Shape, Bulk, Solidity, and other Mechanical affections of its Parts, which concur to enable it to disjoin the Parts of a Body, of such a determinate Texture. And indeed there are not only a great number of Menstruums very different from one another, but their effects evidently appear not to depend upon manifest Qualities, since it several times happens that a Menstruum less Acid, may dissolve this or that Body, which a much stronger Menstruum will not work upon; so Water will dissolve the white of an Egg, which Spirit of Wine will coagulate, and so will Spirit of Salt and Oil of Tartar itself; and thus dephlegmed Spirit of Urine will more readily dissolve filings of Copper than Spirit of Vitriol, and yet the latter will speedily dissolve Crabs Eyes, tho' the other leaves them untouched; so Quicksilver will dissolve Gold in the cold, tho' Aqua Fortis assisted by Heat leaves it untouched; yet Aqua Fortis will dissolve Iron, and Quicksilver will not. And Brimstone will be dissolved by common Oil, tho' not by Aqua Fortis. And I know a Liquor of which one may safely drink a Wine Glass full, tho' it will have such an effect upon Stones and Metals as can scarce be matched. And if specific Medicines may act upon Humours in the Body, after the manner of Menstruums, we may easily guests why they have peculiar Virtues, viz. By reason of their aptness to work upon peculiarly disposed Bodies, so, as I have elsewhere noted, Aqua Fortis will not work upon Silver if too strong, till diluted with Water. And as the dissolution of a Body may partly depend in its disposition, to be acted on by such a Menstruum, from thence may be deduced a reason, why a Medicine which hath good effects in one Disease may have but indifferent ones in others; for though pure Spirit of Wine will easily dissolve Gumm, Guajacum, and that Rosinous matter lodged in the Pores of the Wood, yet the same Menstruum will not work upon the Wood itself. And if so, no wonder that those Medicines which cure one Distemper in one Person, will not cure it in another, since a Variation in the Texture of the Morbific matter, is enough to vary the effects of the Medicines. And that a slight alteration of Texture varies the effects of a Menstruum appears, since, tho' Spirit of Nitre or Salt separate will each dissolve Copper; and tho' the Spirit of Nitre will dissolve Silver, yet if Spirit of Salt be added to it, it soon loses that Quality. And here, tho' some object against specific Medicines, that since they rove up and down in the Blood, they cannot act well on particular Humours, yet if we suppose the Medicines act by impregnating the Blood, and that they turn it into a kind of Menstruum, it is possible that both the Menstruums may be appropriated to the peccant Humour, so as to resolve it more easily than any other Humour of the Body. As if you take some Bone ashes, Crocus Martis, Sawdust, Powdered Sea-Salt, and filings of Gold, and mix them together, common Water will dissolve the Salt and leave the others untouched, and Quicksilver will alone dissolve the Gold: And those that work in Spanish Gold Mines tell us, that Quicksilver poured upon powdered Ore of Gold and Copper mixed, it will scarce meddle with the latter, till the former is licked up. And from what hath been said, we may be furnished with a reason of the effects of Periapta Annulets and Appensa, especially if we consider what hath already been delivered of the Effluviums of Bodies, and the Porosity of Animal Bodies; and tho' these Effluvia be very small in quantity, yet their effects may be more considerable, in as much as they are neither altered nor consumed, by previous digestions, and circulating through Parts, in which they might be in a great measure dispersed, and carried off along with the Excrements. PROP. II. Sometimes a specific Medicine may mortify the over Acid, or other immoderate Particles, that infect the mass of Blood, and destroy their Coagulatory or other Effects. Tho' I believe not that all Distempers are, yet I question not but that a great many are caused either by Acids, or their ill effects or Productions; and which may be cured by specific Medicines two ways, viz. either by mortifying them by a positive Hostility, such as Alkalizate Salts, whether fixed as the lixiviate Salts of Plants, or Volatile, as those of Urine, etc. Or, by taking off or blunting their edges; as a Knife may lose its power of cutting, by putting it in a sheath, or sticking something upon the edge; for the edges of an Acid may be taken off, as well by being lodged in a Porous Alkaly, as by having their edges broken off; and thus it is that Minium takes off the Acidity of Vinegar; Chalk takes off the edge of Aqua Fortis, and Lapis Calaminaris lessens the Acidity of Spirit of Salt and Spirit of Nitre; and that Acids are rather sheathed than altered by these Bodies, I am apt to believe, because as Glauber tells us, they may by a strong fire be drawn out of Lapis Calaminaris much stronger and more dephlegmed than before. And tho' it may be urged by those that plead against specific Medicines, that they act by a manifest Quality, viz. their Alkalious Nature, or their Acid; yet there is so great a variety betwixt Acid and Alkalious Medicines themselves, that I am persuaded they perform a great deal upon the account of something else, besides their Acid or Alkalious Nature, since Aqua Fortis will not dissolve God tho' it will Silver, but if it be altered by an addition of Spirit of Salt, it will dissolve Gold and not Silver. And a different Modification may not only make a difference betwixt Acids, but a contrariety; since Spirit of Salt will precipitate Silver, which Aqua Fortis hath dissolved: And Spirit of Nitre will precipitate out of Butter of Antimony, an Antimonial powder with a considerable Conflict and Effervescence; yet this Butter of Antimony is so highly Acid, that a little quantity of it put into a little Water makes it so sour, that many Chemists call it Acetum Philosophorum. And as there are several kinds of Acids and of Alkalies too, so every Alkaly will not mortify the same Acid; for tho' Chalk will precipitate a Solution of Copper in Aqua Fortis, yet a Volatile Alkaly will not. And indeed when I consider what difference there naturally is betwixt Acids, it is not unreasonable to expect, that there may be Acid Humours produced in the Body utterly unknown to us, and which may require a specific Alkaly to correct them, as it is observed, that tho' neither Spirit of Vinegar, nor Spirit of Salt, nor Oil of Vitriol, will dissolve a Calculus Humanus, yet Spirit of Nitre will, and by that means loses its Corrosiveness. And to what hath been said, I shall add, that I am of opinion that particular Acids may be the occasion of Distempers, which they are by some rather taken to be Remedies; for tho' Acids are looked upon to be of an incisive Nature, and tho' in some cases I am willing to allow them those Virtues; yet I believe that Obstructions and the Diseases depending therein, are caused by Acids coagulating, some fluids disposed to be thickened by them; which might be exemplified by the Coagulation I have made of some Acid Salts, as Spirit of Salt, of the white of an Egg, which by being beaten is reduced to an Aqueous consistence: And Milk will be coagulated not only by Spirit of Salt, but Rennet and Juice of Lemons, and it hath been found by experience, that some Acids transmitted into the mass of Blood, have coagulated it in living Animals. But tho' I believe a great many Distempers are occasioned by Acids, yet I conceive some are occasioned by Acid Salts uniting with other Saline Bodies; as Spirit of Salt, and Spirit of Urine produce a Salarmoniack. And Spirit of Nitre with Salt of Tartar dissolved in common Water will coagulate with it into Salt-Petre; and the same Spirit of Nitre with Spirit of Urine will produce a very fusible Salt, different from either of the Ingredients; and Oil of Vitriol or Oil of Tartar per Deliquium will produce Tartarum Vitriolatum; in which both the Acidity and Alkaliousness of the Ingredients are much infringed, the Body resulting from the composition being different from both the Ingredidients: And if besides these instances we consider how many different Substances may be produced by Nature, I am apt to believe, that specific Qualities are requisite to alter or destroy them, in the Medicines made use of for that purpose. And to what hath been said, I shall further add, that I have mixed two Liquors together neither of which were Acid or Alkalious, and yet the resulting Body was a consistent Coagulum. And I have prepared a certain Liquor, which upon the affusion of Spirit of Urine will be turned into a Jelly. And the like I have produced without the help of either an Acid or an Alkaly. And I have had a Substance prepared without the help of a Volatile Alkaly, which would in a trice coagulate highly rectified Spirit of Wine; and as Spirit of Salt will coagulate the white of an Egg, so will dephlegmed Spirit of Wine; so that an Animal Substance may be coagulated without an Acid. PROP. III. Sometimes a Specific Medicine may help the Patient, Prop. III. by Precipitating the peccant matter out of his Blood, or the other Liquors of the Body in which it harbours. Tho' Precipitation be generally a Consequent of the Mortification of Acids or Alkalies, by Corpuscles of a contrary Quality, yet some Acids and Alkalies may be mixed without a precipitation of any thing; and several Precipitations may be caused without any such manifest Hostility. As in certain mixtures of Spirit of Sal-Armoniac made with Salt of Tartar or Pot-ashes, and Spirit of Nitre, or Aqua Fortis; and also when Spirit of Urine and Salt, are mixed in a certain proportion, make Sal Armoniac, which the Phlegm of those Liquors will keep swimming; and that there may be Precipitations without any appearance of contrariety, is evident, when Silver being dissolved in Aqua-Fortis, the Menstruum is diluted with Thirty or Forty Parts of Distilled Water; for if clean Plates of Copper be immersed in the Solution, the Metal will be slowly precipitated out of it, in the form, not of a Calx, but pure shining Scales of Silver; and if you rub Dantzick Vitriol upon the Blade of a Knife well wetted with Water, the Steel in a trice will be overlaid with a reddish substance, which by its Colour and Signs appears manifestly cupreous. And here I shall add, that there are in Nature, Precipitants which silently precipitate some Bodies dissolved in Urinous Menstruums. And tho' against the Use of Precipitating Medicines, it may be urged, that the Heterogenous Particles precipitated, may be of dangerous consequence, yet they may be less pernicious than those hostile Particles that produce the Disease. And further, they may not be so big, but that it is possible for them to be carried out of the mass of Blood, since those Mineral Substances dissolved in Tunbridge Waters, and the Sulphureous ones in the Bath, chief perform their effects by being dispersed through, and acting on the several Parts of the Body. But moreover it is possible Precipitations may be made in the mass of Blood, without the Medicine getting into it, which is observed in the use of Chalybeat Medicines; where were it urged, that they pass through the Pores of the Guts, than there is no reason why there are not Pores in the Body large enough to carry off the Precipitated Parts of the mass of Blood. And not only Sennertus makes use of Medicines in Fevers, to Precipitate the febrile matter, but Kergerus very solemnly declares that he cured thousands only by a Precipitating Medicine. And that Precipitating may be of use in Physic, I am the more inclined to believe, if a Putrefaction of Humours be rightly assigned as the cause of some Distempers; because I know a Liquor which being dropped into stinking Water, Precipitated a light Feculency out of it, upon which the Liquor was wholly freed from its stink, nor could I perceive that the Feculency itself had any; and what was more remarkable was, that the taste of this Precipitant was neither Bitter, Acid, Urinous or Lixiviate. PROP. IU. Sometimes the Specific Remedy may work by peculiarly strengthening and cherishing the Heart; the part affected, or both. That a Medicine may have peculiar effects on this or that Part, I am inclined to believe for the following reasons. First, because the several Parts of the Body are of differently framed, and have different Humours lodged in them; and consequently the Parts of a Medicine dispersed through the Body, may be more aptly appropriated to be received or detained in those Parts; and the Parts being thus strengthened may be more able to resist the influence of Morbific Humours, by which means they are thrown upon more ignoble Parts, for which reason, some Persons are seized with the Gout; and I know a Gentleman, who tho' he could drink Wine without much hurt, yet Brandy would cause him to have a severe Toothache. But to illustrate what I was saying, of the disposition of some Parts of Medicines to associate themselves with those Parts they seem friendly to; I shall add, that in nourishing Children, Milk does not only afford grosser Faeces, and various other Excrements as Urine, Mucous, and a Humour by insensible Transpiration, but Particles which upon their being assimilated increase the bulk of the Body; and whereas it is observed, that some Cartilages in Children acquire a Bony hardness in older Persons, this change cannot be supposed to be the bare effect of Exsiccation. And as Specific Medicines may confirm the strength of a Part, so they may conduce to the restoreing of strength to the weak Part, by removing Distempered Humours; and this they may do, not only by altering the whole mass of Blood, but their peculiar disposition to act on the Distempered Humour And as the Morbific matter is diversified, according the disposition of the part it is lodged in, so must the Medicine be Specifically appropriated. And as they contribute to the removal of a Distempered Humour, so consequently they will to the strengthening of the fibres of those Parts; either by giving them a firmness; or by correcting their immoderate Heat or Cold; or correcting the Humours lodged in the Pores of the Part, or by takeing away the Convulsive or inordinate motions of the Parts; or by relaxing, or otherwise altering their Pores, or causing the matter lodged there to be expelled by a gentle or violent agitation; as when Cantharideses cause an Excretion of Urine, or Gravel, by irritating the fibres of the Bladder: And the effects of this Medicine alone are sufficient to prove, that there may be Specific Medicines which chief respect particular Parts; since Cantharideses pass through the Body, without affecting any other part but the Bladder. And tho' at the first a Medicine may chief respect a particular part, without altering the Blood, yet when once it hath caused a change in it, the Blood itself, as it successively circulates through that Part, may in some measure act Specifically upon it. And tho' a Medicine may communicate to the Blood Particles of matter so modified, that they may not immediately relieve the Part, by either strengthening it, or causing the Distempered matter to be carried off by a gentle irritation, yet it may do it by both these ways, as when Rhubarb is taken, it not only purges the Liver of Choler, but strengthens the Tone of the Parts by its astringency. And Osteocalla is observed to be a Specific, by promoteing the Generation of a Callus, to cement broken Bones. PROP. V Sometimes a Specific Medicine may act, Prop. V. by producing in the mass of Blood such a disposition, as may enable Nature, by correcting, expelling, or other fit ways, to surmount the Morbific matter, or other cause of the Disease. And this is agreeable enough with what most Moderns hold, viz. That Distempers chief depend upon the Temper and ill Constitution of the Humours. And a change in the Humours may be effected. By furnishing the Blood with some sort of active Corpuscles, which may agitate and ferment it, and to quicken the Circulation of the Blood. Upon which occasion it may be necessary to advertise, That the Medicines usually made use of for that purpose being very hot; there are several Constitutions of Patients, and several other Circucumstances, upon which account they do more harm by their Heat, than good by their Spirituousness; besides the sluggishness and want of fermentation in the Blood, may proceed from causes which this sort of Medicine will not correct; for I have tried, that a Vinous Spirit would not dissolve Blood which was a little dried, nor draw a Tincture from it, tho' an Urinous Spirit presently did; so that a Specific Medicine in such a case may perform what is intended, without the inconveniences which other Medicines are liable to: For we know that experienced Physicians, call some Medicines cold Cordials, as Sorrel, which hath an Acid taste; and it is possible sometimes those Humours which make the Blood sluggish may not be of a cold, but a hot Nature, in which cases hot Remedies may rather increase than diminish their ill effects; as if the white of an Egg be reduced to Water by beating, Spirit of Wine will instead of diminishing increase its Viscidity. And I once prepared a Vegetable Substance, which upon an addition of Wine became much more Viscous than before. But to proceed, a Specific Medicine may alter the mass of Blood, by contributing to its Tenacity, without respect to its Fermentation; for if the Blood be too thick, it cannot readily pass through the small Capillary Vessels, by which Circulation is in a great means retarded; as on the other Hand, if it be too thin, it gets out of the Capillary Vessels, and first Stagnates, and then Putrifies; but these ill consequences may be prevented, by such Medicines as either on the one Hand divide the Parts of the Blood, and make them more minute, or on the other such as associate them, and stick them together. Another way by which a Specific Medicine may rectify the state of the Blood, is, by working so upon the Heart, as to make it transmit Blood more advantageously; and that either by corroborating its fibres, or dissolving some ill distempered matter, that obstructs the Contraction of it; and that a small alteration in the Constitution of the Heart, may do much in respect of the Circulation of the Blood, will be easily granted by any one, that does but consider what insensible Agents actuate it. And that the almost insensible Obstruction of Circulation produces considerable effects in the Body is evident, from the effects of Sorrow, which presently puts the whole Body out of order; and also from the effects of Joy or shame, both of which promote the Circulation of the Blood; and it hath been observed, that Joy hath had so sudden and considerable an effect, as to take off the sharpness of Hunger; and that Medicines may affect the Heart after the same manner, I am inclined to believe; especially since I knew a Lady, who was so affected upon the smell of perfumed Gloves, that the Blood flew into her Face, and put such a colour into it as if she had blushed. And if the state of the Blood may be thus altered, it may much contribute to the removal of some very troublesome Distemper, induced for want of a due Circulation of the Blood. PROP. VI Sometimes a Specific Remedy may unite with the peccant matter, and compose a Quid Nutrum, which may be less offensive to Nature, tho' not so easily expelled. And this seems to me to be the most genuine effects of a Specific Medicine; and when peccant Acids are lodged in the Spleen, or any other part less sapid, Alkalies may unite with them, without creating any manifest disturbance; and form a harmless Liquor; as Aqua Fortis, by being digested and distilled with a very ardent Spirit, loses its corrosive Acidity and ill scent, and becomes a harmless, sweet, and fragrant Liquor; and I knew one who relieved a Nephritick Patient, with the use of inflammable Spirits. And I have elsewhere shown, that Spirit of Wine acts not upon all Acids uniformly, but variously, according to the Nature and proportion of the Acid. And Spirit of Wine mixed with rectified Spirit of Urine, will in a great measure take off the corroding Qualities of it, and composes a Salt which is weaker than the Spirit, and being sublimed or reduced to a Liquor, becomes a good Medicine; and with a little skill will make a very good Menstruum in several Chemical Experiments. A few Grains of Glass of Antimony taken inwardly, will both Vomit and Purge, but if instead of Spirit of Wine we make use of that of Vinegar, and when by digestion the Liquor is sufficiently impregnated, it be abstracted, Antimonial and Acetous Corpuscles will emerge, several Grains of which may be taken without either Vomiting or Purging; from whence it appears, that all Correctors are not to be esteemed Alkalies, since Acids themselves prove to be Correctors too. And after a like manner not improbably, the Poisons of Animals and others may be subdued. And it is not improbable, that by a Combination of a Distempered Humour with a Medicine a Salutiferous Liquor may be form, and tho' sometimes a Medicine is altered before it comes to the part affected, yet that alteration may render it Medicinal: An instance of the former we have in the Preparation of Mercurius Dulcis, where by uniting Poison with Quicksilver, an Efficacious Medicines is made; and an Illustration of the latter may be brought from that Odour which it gives to the Urine of the Person who takes it, different from any smell it had of itself before. And tho' against what hath been been said, for Specific Medicines some may offer that there are some which are only externally applied; yet from what hath been said, of the Porosity of Bodies and the effects of Effluvia, it will easily appear how they may influence the Body, and alter the Humours which circulate in it; and to what is there offered we may reasonably add, the ill effects of Annulets of Arsenic mentioned by Diemerbreck, and the effects of Cantharideses upon some Persons who only wore them in their Pockets. And indeed there are a great many Medicines externally Specificks, which one would not take to be so, as Camphire, which internally is very hot and good in some Malignant Fevers, yet outwardly it is used to take off Heat Pimples in the Face, and in cooling Ointments, and against Burns; and Spirit of Wine, though very hot when internally used, yet it, if presently applied, takes out the fire of Burns. And so mild a Body as Bread, if chewed and outwardly applied, hath considerable Virtues in external affections. And I have several times eaten a thing without any such effect, which a Physician told me externally applied would Purge Children, being neither offensive in colour, smell or Gripeing. And to these instances I shall add, That Galen tells us, that an Epileptic Boy was free from such Fits, as long as he wore only Peony Root as an Appensum. And I knew one who was Paralytic, that was suddenly relieved in violent Cramps, only by handling the Tooth of a River-Horse; and I as well as others have been relieved in the Cramp, by putting a Ring made of an Elks Hoof upon my finger. And I knew another cured of an Incontinentia Vrinae, by the sole use of an Appensum. And a Lady had a Scrofulous Tumour dispelled, only by successively applying the Body of a dead Man to the part affected, till the cold sensibly penetrated into it. And I myself had not only a violent Haemorrhage speedily stopped, by holding moss of a dead Man's Skull in my hand; but a Gentleman told me, that if when he was let Blood he held it in his hand, no Blood would flow out till he laid it aside. And another told me, that he had been freed from a Palpitation of his Heart, which usually fell upon him after a few hours sleep with great terror, only by wearing smooth and flat Cornelians in a bag over the pit of his Stomach. Galen tells us, That jasper's worn after the same manner are good for the Stomach; and Monardes' tells us, that the Bleeding of the Hemorrhoids have been stopped, by wearing a Ring made of a Bloodstone upon the fingers. And not only Boetius and Johannes de Laet commends Lapis Nephriticus, but the experienced Monardes' and others. And Untzerus tells us, that by wearing this Stone some Parts of the Stone were made so minute as to be expelled out at the Eyes: And that one that had a Catarrh was Purged fourteen times in one day by wearing of it; and it had the like effect, tho' not so strongly upon another. But, To conclude this Discourse, I shall here advertise the Reader, that tho' I have laid down several ways by which Specific Medicines might operate, yet I think not those always singly effectual, but that sometimes they jointly contribute to the producing of the effect; without enlarging upon this account I shall only subjoin, that I hope from what hath been already delivered it may appear, that the Doctrine of Specific Medicines is not irreconcilable to the Principles of the Corpuscular Philosophy. CHAP. XII. A short account of Ambergrease communicated in the Transactions of October 6. 1673. I Received the following account from one of the Committee of the East-India Company. Ambergrease is not the Scum or Excrement of the Whale, etc. but issues out of the Root of a Tree, which always shoots out its Roots towards the Sea, seeking the warmth of it, thereby to deliver the fattest Gum that comes out of it. Which Tree otherwise by its copious fatness might be burnt and destroyed. Wherever it is shot into the Sea, it is very tough, and can scarce be loosened from the Root, except by its own Weight or the Motion of the Sea. If you Plant the Trees, where the stream sets to the shore, it will cast it up to great advantage. March 1. 1672. in Batavia Journal, Advice From, etc. FINIS. ADVERTISEMENT. THE Works of the Honourable Robert Boyl Esq Vol. 1st. and 2d. Sold by J. Phillip's at the Kings-Arms, and J. Taylor at the Ship in St. Paul's Churchyard. The Table. A AIR not the Primum Frigidum. Page 103 Of the Air's Temper. p. 107 The Doctrine of Antiperistasis examined. p. 145 Of the Pressure of the Airs Spring on Bodies under Water. p. 268, 271 Of the ●tmospheres of Consistent Solids. p. 412 Of Ambergrease. p. 551 B To preserve Birds, etc. p. 353 Of the Bladders of Air in Fishes. Ibid. The natural History of Human Blood. p. 459 Of the Colour of Human Blood. p. 460 516. Of its Taste. Ibid. Of its Odour. Ibid. Of its Heat. Ibid. Of its Inflamability. Ibid. Of the Acid Parts naturally mixed with Human Blood. p. 461 Of its Specific Gravity. Ibid. Of the Specific Gravity of the Consistent part. p. 462 Of the Consistence of Human Blood. Ibid. Of its Disposition to Concretion. Ibid. What Liquors or Salts Coagulate it. Ibid. What hinder its Coagulation. Ibid. What Liquors preserve it, etc. Ibid. Of the Volatile Salt of Human Blood. Ibid. Of the Phlegm and Oils of Human Blood. p. 465 Of the fixed Salt of Human Blood. p. 467 Of its Terra Damnata. p. 468 What substances may be Chemically obtained from it. Ibid. C Of the Mechanical Production of Cold p. 1, 189 Cold produced by a Solution of Salarmoniack. p. 2 — by a Mixture of Spirit of Salt and Urine. p. 3 — by Spirit of Rock Allom. Ibid. — by oil of Vitriol and Salarmoniack. p. 4. Potential Coldness Mechanically explained. p. 5 Degrees of Cold neither to be judged of by our Sensory nor Weather-Glasses. p. 11 Of the degrees of Coldness in several Bodies. p. 48 Of the Circumscription of the Sphere of activity of Cold. p. 53, 85 Of the Preservation of Bodies by Cold p. 55 Of the Contraction of Liquors by Cold. p. 66 Of the Expansive force of Congelation. p. 83 What Mediums Cold may be diffused through. p. 88 Of the strange effects of Cold. p. 120 Promiscuous Experiments concerning Cold. p. 129 Mr. Hobbes' Doctrine of Cold examined. p. 158 Of the Positive and Privative Nature of Cold. p. 180 D Observations about Diamonds and other shining Bodies. p. 138, 139, 141. E What the success of Experiments depends on. p. 9 The Earth not the Primum Frigidum. p. 100 Earth the Summum Frigidum. p. 102 Experiments about Explosions. p. 232 Of the strange Subtlety of Effluviums. p. 415 Of their Efficacy. p. 424 Of their determinate Nature. p. 431 F Of Bodies capable of Freezing others. p. 38 Of Bodies disposed to be Frozen. p. 42. Of Bodies not disposed to be Frozen. p. 45 The effects of Frost on Solid Bodies. p. 123 Several Experiments about Freezing. p. 164 Fire and Flame made Ponderable. p. 205, 206, 210. Of the Relation betwixt Flame and Air. p. 218, 220, 223. Flame preserved under Water. p. 225 Of the Propagation of Flame in Vacuo. p. 226, 227 Of the Relation betwixt Air and the Flamma Vitalis of Animals. p. 229 G The effects of Gunpowder dissolved in Water. p. 4. Of the Perviousness of Glass. p. 213 A comminution of Gold into Powder. p. 363 Of the Nature of Granates. Ibid. Of the Origin of Gems. p. 380 Of the Virtues of Gems. p. 397 H Heat produced by a Mixture of Salt-Petre and oil of Vitriol. p. 4 Of the Mechanical production of Heat. p. 191 Hydrostatical Paradoxes made out. p. 279 A new Hydrostatical Instrument, and its uses proposed. p. 311 Observations about Hurricanes. p. 365 I Of the Levity of Ice and its cause. p. 68 Observations and Experiments concerning Ice. p. 91 What Liquors soon dissolve Ice and Snow. p. 96 The Qualities of Ice. p. 172 L The Expansion and Contraction of Liquors measured. p. 75 Of the Relation betwixt Light and Air. Of the Levity of Bodies under Water. p. 265 A self moving Liquor. p. 351 A Preparation of Liquid Laudanum described. p. 354 M Of Mercury growing hot with Gold. p. 203 Of the growth and increase of Metals. p. 318 Medicina Hydrostatica. p. 329 The weight of several Bodies weighed in Air and Water. p. 346 Passages relating to the Art of Medicine. p. 355 Of Specific Medicines. p. 528 Their operations Mechanically solved. p. 531 That by their uniting with a Distempered Humour, a third Body may be produced not so offensive to Nature. p. 547 N Nitre not the Grand Efficient of Cold. p. 104 Of the effects of Nitre in Freezing. p. 131 Of the Aerial Noctiluca. p. 245 Of the Reason of Noctilucas. p. 247 Of the Icy Noctiluca. p. 255 Of the Subtlety of its Parts. p. 259 O Oly of Vitriol and Salarmoniack mixed together. p. 8 A Hydrostatical way of estimating Oars. p. 321 P Of the Primum Frigidum. p. 99 A Chemical Analysis of Pearls. p. 370 Of the Porosity of Bodies. p. 440 Of the Porosity of Animal Bodies. p. 450 The effects of Putrefaction and Fermentation on Human Blood. p. 485 R What Refrigeration depends on. p. 6 Strange Reports. p. 373 S Of the different Pressure of Solids and Fluids. p. 272 Of the Serum of Human Blood. p. 474 Of the Spirit of Human Blood. p. 483 Spirit of Human Blood what. p. 487 Of what Classis of Saline Bodies it is of p. 488 Whether different from Spirit of Urine, etc. p. 490 Of its proportion to the Substance it is drawn from. p. 491 Of its Consistence and Specific Gravity. p. 492 Of its Odour, Taste, and Colour. p. 494 Of its dissolving power. p. 495 Of the Coagulating power of Spirit of Human Blood. p. 499 Of its Precipitating power. p. 500 Of its affinity with some Chemical Oils, etc. p. 501 Of the Relation betwixt Spirit of Human Blood and Air. p. 504 Of its Hostility with Acids, etc. p. 506 Of its Medicinal Virtues. p. 508, 511 T The effects of a Mixture of Salt of Tartar and Water. p. 193 What Tinctures may be drawn with Spirit of Human Blood. p. 497 V Titles for the Natural History of Human Urine. p. 472 W Of the ascent of Water in Weather-Glasses. p. 30 Of the Expansion of Water and other Freezing Liquors. p. 62, 187 Of the Expansive force of Freezing Water. p. 79 Water not the Primum Frigidum. p. 702 The weight of Bodies froze and unfroze. p. 126 Whether ●ot Water freezes sooner than Cold. p. 134 Of the weight of Water in Water. p. 277 FINIS.