Difference in their Velocity We say some small Difference because if we take two Globes of different materials and weights but of the same or equal diameters as V. G. one of Lead the other of Wax we shall be very far from finding that the Heavier will be carried down more swiftly than the Lighter in a proportion to the excess of its Gravity For if one be ten times heavier than the other yet shall not the Heavier therefore both being turned off in the same instant arrive at the ground ten times sooner than the Lighter but at the same time as the heavier arrives at the ground from the altitude of 10 Fathoms the lighter shall come within a foot of the earth so far short doth the lighter come of being nine fathoms behind the Heavier And the Cause why the Lighter Globe of Wax is carried so swiftly is the same with that why a bullet of Lead of only an ounce weight is carried down as swiftly as another bullet of 100 pound And what though the Globe of Wax be as great in circumference as the other of Lead and somewhat greater yet seeing still it hath fewer parts to be attracted it therefore requires fewer magnetical rays to its attraction with equal velocity to the heavier But the Cause why it is carried somwhat though very little slower than the heavier is to be derived chiefly from the Aer resisting it underneath the Aer being more copious in proportion to the virtue Attrahent in respect of the greatness of its Ambite or Circumference and thence is it that Cork Pith of Elder straws feathers and the like less compact and so more light bodies fall down much more slowly From this Experiment and the Reason of it we have an opportunity of observing and easily understanding the Distinction of Gravity into Simple and Adjectitious the Former being that which is competent to a body though unmoved and whose quantity may be exactly determined by the balance suspending the body in the aer the Latter being proper only to a body moved and vanisheth as soon as the body attaineth quiet and whose measure is to be explored both from the quantity of the simple gravity which the body bears during its quiet and the Altitude from which it falls Thus assuming two Bullets the one of an ounce the other of 100 pound Simple Gravity according to the Scales the Adjectitious Gravity of the Lesser bullet acquired by the increment of its velocity during its descent must be less proportionably to its simple gravity than the Adjectitious gravity of the Greater bullet acquired by the increment of its Velocity during its Descent in the same time and from the same altitude because the space and time of the descent of both being equal the proportion of the acquired gravity of each must be respondent to the proportion of the simple gravity of each So that if in the end of the fall of the Lesser bullet of an ounce weight the Adjectitious Gravity of it shall amount to 10 ounces the Adjectitious gravity of the Greater of 100 pound weight shall in the end of its fall amount to a thousand pound nor can the Acquired Gravity of the Lesser ever equal that of the Greater unless it fall from a far greater Altitude Here perhaps you 'l Demand our opinion concerning that admirable because superlative Velocity which Galilaeo and other Mathematicians conceive that a bullet would acquire in case it should fall to the â—arth from those vast we might have said Immense heights of the Moon Sun and region of the Fixed starrs Of this therefore we say in short 1 That in this case Mathematicians are wont to suppose that there are the same Causes of Gravity and Velocity in those sublime places as are observed here with us below or neer the surface of the Earth and if they be not certainly our Description and Computation must be altogether vain and fruitless For if the Cause of Gravity and consequently of the Velocity be the Attraction made by the magnetique rays transmitted from the Earth forasmuch as those magnetique rays must become more Rare and fewer of them arrive at a body by how much farther it is removed from the Earth though perchance a bullet might be attracted down from the region of the Moon and if so the motion of the bullet would be very slow for a good while in respect of the very few magnetique rays that could arrive to that great height yet from that far greater height of thâ— region of the Fixt stars a bullet could not be attracted at all it being impossible that any magnetique ray should be transmitted so far as half way thither 2 But supposing that the magnetique Virtue of the Earth did extend thither and that a bullet from whence soever falling should begin its motion with that speed and proceed according to the same degrees of Acceleration which we observe in a stone or bullet falling from a very high tower then must it of necessity acquire that incredible Velocity which our Mathematicians describe To Particular conceding the Distances or Intervals betwixt the Earth and each of those Caelestial Orbs which our modern and best Astronomers generally assign a bullet would fall from the body or rather the Limbus of the Moon to the Earth in two hours and an half from the Limbus of the Sun in eleven hours and a quarter from the region of the Fixt stars in 39 hours and a quarter And so if we imagine the Earth to be perforated to the Centre since a bullet would fall from the superfice thereof down to the Centre in 20 minutes or the third part of an hour the same bullet coming from the moon would pervade the same space from the superfice of the Earth to the Centre of it in one minute and twenty seconds or the third part of a minute coming from the Sun it would pervade the same semidiametral space of the Earth in seventeen seconds and coming from the region of the Fixt stars it would percur the same semidiametral space of the Earth in five seconds So incredibly great would be the Velocity of a bullet falling from such vast Altitudes And this we think sufficient concerning the Downward motion of Bodies accounted Heavy SECT III. THe Remnant of our praesent Province consists only in the consideration of the Upward motion of Heavy Bodies PROJECTED concerning which the principal Enquiries among Philosophers are 1 VVhat and whence is that Force or Virtue motive whereby bodies projected are carried on after they are separated from the Projicient 2 What are the Laws of their motion Direct and Reflex Concerning the FIRST therefore we observe that Aristotle in 8. physic cap. ult and most of his Sectators confidently affirm that a stone thrown out of a sling an arrow shot from a bow a bullet discharged from a Gun c. is moved only by the Aer from the time of its separation from the sling bow or Gun and
long as the orifice in the Neb remains stopped is the defect of room for the aer pressed upon by the basis of the Water to recur into upon its resignation of place because all places being full there can be none whereinto the inferior aer may recede until upon deobstruction of the hole above the circumjacent aer enters into the cavity of the Vessel and resignes to the aer pressed upon below and so the motion begins and continues by a successive surrender of places For though the aer contiguous to the bottom of the Irrigatory be not sufficient to resist the compressure of so great a weight of water by the single renitency of the Confluxibility of its atomical particles yet the next contiguous aer possessing the vicine spaces and likewise wanting room to recede into when compelled by the first aer aggravates the resistence which becomes so much the greater by how much the farther the pressure is extended among the parts of the circumjacent aer and by so much the farther is the pressure of the circumjacent aer extended by how much the greater is the pressure of the next contiguous aer and that pressure is proportionate to the degrees of Gravity and velocity in the body descendent Which is manifestly the reason why the water doth not descend through the perforated bottom of the Vessel viz. because the Gravity thereof is not sufficient to counterpoyse so diffused prolix and continued resistence as is made and maintained by the confluxibility of the parts of the circumambient aer successively uniting their forces Notwithstanding this seeming plenitude we may absolve our reason from the intricacy of the scruple by returning that though all places about the Tube are filled with aer yet not without some Laxity So though there be indeed no sensible or coacervate space wherein there are not some parts of the aer yet are there many insensible or disseminate spaces or â—oculaments variously interspersed among the incontiguous in all points particles of the aer which are unpossessed by any Tenent at all For the familiarizing of this Nicety let us have recourse once again to our so frequently mentioned example of a heap of Corne. When we have poured Corne into a Bushel up to the brim thereof the capacity seems wholly possessed by the Graines of Corne nor is there therein any space which sensibly contains not some Graines yet if we shake the bushel or depress the Corne the Graines sink down in a closer posture and leave a sensible space in the upper part of the bushel capable of a considerable access or addition The reason is that the Grains at their first infusion in respect of the ineptitude of their Figures for mutual contact in all points of their superâ—icies intercept many empty spaces betwixt them which dispersed minute inane spaces are reduced to one great and coacervate or sensible space in the superior part of the Continent when by the succussion of the vessel the Grains are disposed into a closer posture i. e. are more accommodated for mutual contingency in their ends and sides Thus also may aer be so compressed as the Granules or insensible particles of it being reduced to a more close or dense order by the sâ—bingression of some particles of the aer nearest to the body Compressing into the incontiguities of the next neighbouring aer may possess much less of space then before compression and consequently surrender to the body propelling or compressing leaving behind a certain space absolutely devoid of aer at least such as doth appear to contain no aer But this Difficulty Hydra-like sends out two new Heads in the room of one cut off For Curiosity may justly thus expostulâ—te 1 Have you not formerly affirmed that no body can be moved but it must compel the aer forward to suffer a certain subingression of its insensible particles into the pores or Loculaments of the next contiguous aer such as is requisite to the leaving of a space behind it for the admission of the body moved And if so how comes it that when most bodies are moved through the aer with so much facility and therefore cause the parts thereof before them to intrude themselves into the incontiguities of the next vicine aer with a force so small as that it is altogether insensible yet in this case of the Experiment is required so great a force to effect the subingression and mutual Coaptation of the parts of the aer The Cause seems to be this In all common motions of bodies through the liberal aer there is left a Space behind into which the parts of the aer may instantly circulate and deliver themselves from compression and so there is a subingression and Coaptation of only a few parts necessary and consequently the motion is tolerated without any sensible Resistence but in this Case of the Experiment in regard there is no place left behind by the Propellent into which the compressed parts of the aer may be effused necessary it is that the parts of aer immediately contiguous to the body Propellent in their retrocession and subingression compress the parts of the next contiguous aer which though they make some resistence proportionate to their measure of Confluxibility do yet yeild retrocede and intrude themselves into the incontiguities of the next contiguous aer and those making also some resistence likewise yeild retrocede and insinuate themselves into the Loculaments of the next which acts the like part upon the next and so successively So that a greater force then ordinary is required to subdue this gradually multiplied resistence successively made and maintained by the many circumfused parts of the aer and to effect that the retrocession subingression and coaptation of the parts of the aer be propagated farther and farther untill convenient room be made for the reception of the body Propellent 2 Whence do you derive this Resistence of the Aer From its Gravity For the Aer of its own nature is Heavy and can be said to be Light only comparatively or as it is less ponderous then Water and Earth nor can there be given any more creditable reason of the Aers tendency upward here below near the convexity of the Earth then this that being in some degree ponderous in all its particles they descend downwards from the upper region of the Atmosphere and in their descent bear upon and mutually compel each other untill they touch upon the surface of the Earth and are by reason of the solidity and hardness thereof repercussed or rebounded up again to some distance so that the motion of the Aer upwards near the face of the Earth is properly Resilition and no natural but a violent one Now insomuch as the Aer seems to be no other but a common Miscelany of minute bodies exhaled from Earth and Water and other concretious sublunary and proportionately to their Crassitude or Exility emergent to a greater or less
of Atoms And this easily hands us to the natural scope of that passage in Laertius 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Esse Atomos Inane Universorum principia caetera omnia Lege sanciri as also of another in Empiricus 1. hypot. 30. 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 VERE esse Insectilia ac Inane However if any please to prefer the exposition of Magnenus that Democritus by that unfrequent and gentilitious phrase Nomo esse Qualitates would have the determinate nature of any Quality to consist in certa quadam lege proportione inter agens patiens in a certain proportion betwixt the Agent and Patient or object and sensorium we have no reason to protest against his election For we shall not deny but what is Hoâ—y to the palate of one man is Gall to another that the most delicious and poynant dishes of Europe are not only insipid but loathsome to the stomachs of the Iapones who in health eat their Fish boyled and in sickness raw as Maffeus in libro de Iaponum moribus reports that some have feasted upon Rhubarb Scammony and Esula which most others are ready to vomit and purge at the sight of that Serpents are dainties to Deer Hemlock a perfect Cordial to Goats Hellebor a choyce morsel to Quails Spiders restorative to Monkeys Toads an Antidote to Ducks the Excrements of man pure Ambre Grise to Swine c. All which most evidently declare the necessity of a certain proportion or Correspondence betwixt the object and particular organ of sense that is to apprehend and judge it But since the Notion of a Quality is no rarity to common apprehension every Clown well understanding what is signified by Colour Odour Sapour Heat Cold c. so far as the concernment of his sense we are no longer to suspend our indagation of their possible ORIGINE in the general Which were our Atoms identical with the Homoiomerical Principles of Anaxagoras formerly described and exploded might be thought a task of no difficulty at all in regard those Consimilarities are supposed actually to contain all Qualities in the simplicity of their nature or before their Convention and Disposition into any determinate Concretion i. e. that Colour Odour Sapor Heat Cold c. arise from Colorate Odorate Sapid Hot Cold particles of the First Catholique Matter But insomuch as Atoms if we except their three congenial Proprieties viz. Magnitude which by a general interest retains to the Category of Qualities Figure and Motion are unanimously assumed to be Exquales seu Qualitatis Expertes absolutely devoid of all Quality it may seem at first encounter to threaten our endeavors with infelicity and damp Curiosity with despair of satisfaction And yet this Giant at distance proves a mere Pygmie at hand For the Nakedness or Unqualifiedness of Atoms the point wherein the whole Difficulty appears radicated to a closer consideration must declare it self to be the basis of our exploration and indispensably necessary to the Deduction of all sensible Qualities from them when disposed into Concrete Natures Because were any Colour Odour c. essentially inhaerent in Atoms that Colour or Odour must be no less intransmutable then the subject of its inhaesion and that Principles are Intransmutable is implied in the notion of their being Principles for it is of the formal reason of Principles constantly to persever the same in all the transmutations of Concretions Otherwise all things would inevitably by a long succession of Mutations be reduced to clear Adnihilation Besides all things become so much the more Decoloured by how much the smaller the parts are into which they are divided as may be most promptly experimented in the pulverization of painted Glass and pretious stones which is demonstration enough that their Component Particles in their Elementary and discrete capacity are perfectly destitute of Colour Nor is the force of this Argument restrained only to Colour as the most eminent of Qualities sensible but extensible also to all others if examined by an obvious insistence upon particulars Now having taken footing on the necessary Incompetence of any sensible Quality to the Material Principles of Concretions we may safely advance to our Investigation of the Reason or Manner how Colour and all other Qualities may be educed from such naked and unqualified Principles And first we must have recourse to some few of the most considerable EVENTS consignable to Atoms as well as to their 3 inseparable Proprieties The primary and to this scope most directly pertinent Events of Atoms are only two viz. 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 ORDER and SITUATION That Leucippus and Democritus besides those two eminent events 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Concretion and Secretion from which the Generation and Corruption of all things are derived have also attributed unto Atoms two other as requisite to all Alteration i. e. the procreation of various Qualities namely Order and Position is justifiable upon the testimony of Aristotle in lib. de ortu interitu however He was pleased in 8. Metaphys cap. 2. interpreting the Abderitane terms of Democritus to adnumerate 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Figure unto them and thereupon inferr that Atoms are different 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 i. e. aut Rhysmo quod est Figura aut Trope quod est situs aut Diathege quod est ordo in Metaphys 1. cap. 4. to exemplifie this difference in Letters of the Alphabet saying that A and N differ in Figure A N and N A in order and Z N in situation Which is the same with what Empiricus 2. advers phys reports to have been delivered by Epicurus True it is his Disciple Lucretius exceeded him in the number of Events assignable to Atoms in order to the emergency of all sensible Qualities from them for he composing this Distich Intervalla Viae Connexus Pondera Plagae Concursus Motus Ordo Positura Figurae confounds both Events and Conjuncts together wherein He seems to have had more regard to the smoothness of his Verses then the Methodical traction of his Subject For Motion Concurse and Percussion are the natural Consequents of Gravity and Distance and Connexion are included in Position and Wayes or Regions belong to Order as may be exemplified in the former Letters which respective to their remote or Vicine Position and their Change from the right to the left hand exhibite to the sense various faces or apparences That those two Conjuncts Magnitude and Motion are necessarily to be associated to Order and Position is evident from hence that if it be enquired why there is in Light so great a subtility of parts as that in an instant it penetrates the thickest Glass but so little in Water as that it is terminated in the superfice thereof what more verisimilous reason can be alledged to explain the Cause of that difference in two fluid bodies then this that the Component Particles of Light are more minute or have less of Magnitude then those of Water And if it be enquired why
conspurcatus attrectaret nisi incredibili voluptatis aestro percita essent Genetalia And let us but abate the temptation of this sense and libidinous invitement of it praeambulous to the act of Congression and we shall soon confess that so magnified delight of sensuality to be no other than what the noblest of Stoicks Marcus Antoninus defined it 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 but the attrition of a base entrail and the excretion of a little snivel with a kind of convulsion as Hippocrates describes it This is that Fidus Achates or constant friend that conserves us in our first life which we spend in the dark prison of the womb ushers us into this which our improvidence trifles away for the most part on the blandishments of sensual Appetite and never forsakes us till Death hath translated us into an Eternal one For when all our other unconstant senses perish this faithful one doth not abandon us but at that moment which determines our mortality Whence Aristotle drew that prognostick de Anim. lib. 3. cap. 13. that if any Animal be once deprived of the sense of Touching death must immediately ensue for neither is it possible saith He that any living Creature should want this sense nor to the being of it is it necessary that it have any other sense beside this In a word this is that persuasive sense and whose testimony the wary Apostle chose to part with his infidelity and to conclude the presence of his revived Lord. That painful sense on the victory of whose torments the patient souls of Martyrs have ascended above their faith That Virtual and Medical sense by which the Great Physician of diseased nature was pleased to restore sight to the blind agility to the lame hearing to the deaf to extinguish the Feaver in Peters Mother-in-Law stop the inveterate issue in his Haemorhoidal Client unlock the adamantine gates of death and restore the widows son from the total privation to the perfect habit of life 2 That some Qualities are sensible to the Touch which yet are common to the perception of other senses also for no scholler can be ignorant of that Division of sensibles into Common and Proper and that among the Common are reckoned Motion Quiet Number Figure and Magnitude according to the list of Aristotle 2 de Anim. cap. 6. 3 and principally That the Qualities of Concretions either Commonly or Properly appertaining to the sense of Touching are to be considered in their several Relations to the Principles on which they depend First some result from the Universal matter Atomes in this respect that they intercept Inanity or space betwixt them and of this original are Rarity and Density with their Consequents Perspicuity and Opacity Secondly Some depend on the Common Materials in this respect that they are endowed with their three essential Proprieties Magnitude Figure Motion and that either Singly or Conjunctly 1 Singly and either from their Magnitude alone of which order is the Magnitude oâ— Quantity of any Concretion and the Consequents thereof Subtility and Hebetude or from their Figure alone of which sort is the Figure of every thing and the Consequents thereof Smoothness and Asperity c. or only from their Motivâ— Virtue of which kind is the Motive Force inhaerent in all things in thâ— General and that which assisteth and perfecteth the same in most things the Habit of Motion and particularly Gravity and Levity 2 Conjuncâ—ly from them all of which production are those commonly called the â—our First Qualities Heat Cold Dryness Moysture as also those which â—râ— deduced from them as Hardness Softness Flexility Ductility and all others of which Aristotle so copiously but scarce pertinently treateth in his fourth book of Meteors and lastly those by vulgar Physiologist named Occult Qualities which are also derivative from Atoms in resâ—â—ct of their three essential Proprieties and among these the most eminent and generally celebrated is the Attractive Virtue of the Loadstone Now on each of these we intend to bestowe particular speculation allowing it the â—â—me order which it holds in this scheme which seems to be only a faithful Transsumpt of the method of Nature and we shall begin at Rarity and Density 1 Because nothing can be generated but of Atoms commixt and that Commixture cannot be without more or less of the Inane space inâ—â—rcepted among their small masses so that if much of the Inane space 〈◊〉 intercepted among them the Concretion must be Rare if little Dense of meer necessity 2 Because the Four First reputed Qualities Heat Cold Dryness Moysture are posterior to Rarity and Density as appears by that of Aristotle physic 8. cap. 16. where according to the interpretation of Pacius He intimates that Heat and Cold Hardness and Sofâ—ness are certain kindes of Rarity and Density and therefore we are â—o set forth from them as the more Common in Nature and consequently the more necessary to be known a Generalioribus enim tanquam notioribus ad minus Generalia procedendum is the advice of Arist. physic 1. cap. 2. SECT II. COncerning the immediate Causes of Rarity and Density in Bodies divers Conceptions are delivered by Philosophers 1 Some observing that Rare bodies generally are less and Dense more Ponderous and that the Division of a body into small parts doth usually make it less swift in its descent through aer or water than while it was intire have thereupon determined the Reason of Rarity to consist in the actual division of a body into many small parts and on the contrary that of Density to consist in the Coadunation or Compaction of many small parts into one great continued mass But These considered not that Chrystal is not more rare though less weighty proportionately than a Diamond nor that the Velocity of bodies descending doth not encrease in proportion to the difference of their several Densities as their inadvertency made them praesume there being sundry other Causes besides the Density of a body assignable to its greater Velocity of motion in descent as the Heroical pen of Galileo hath clearly demonstrated in 1. Dialog de motu and our selves shall professedly evince in convenient place 2 Others indecently leaping from Physical to Metaphysical speculations and imagining the substance of a body to be a thing really distâ—nct from the Quantity thereof have derived Rarity and Density from the â—â—veral proportions which Quantity hath to its substance as if in Rarefaction a Body did receive no mutation of Figure but an Augmentation and in Condensation a Diminution of its Quantity But the excessive subtility or rather absolute incomprehensibility of this Distinction doth evidently confess it to be meerly Chimerical as we have formerly intimated in our discourse concerning the proper and genuine notions of Corporiety and Inanity 3 A Third sort there are who having detected the incompetency of the first opinion and absolute unintelligibility of the Second judiciously desume the more or less of Rarity in any body
Water and that of the Aer â—â—â—sisteth only in Degrees or more and less And though the 〈◊〉 of the Aer may be thought very inconsiderable in comparison o◠〈◊〉 great Violence imprest upon a Cannon Bullet shot upwâ—rd 〈…〉 the Aer yet be pleased to consider that it holds some 〈◊〉 proportion with the Renitency oâ— the Water Which 〈…〉 that we may understand compare we not only the very 〈◊〉 Ascent of a stone thrown upward from the bottome of the Sea to the large ascent of the same stone with equal force from the Earth thrown up into the Aer but also the almost insensible progress of a Bullet shot from a Cannon transversly through Water with that vast progress it is commonly observed to make through the Aer and we shall soon be convinced that as the Great Resistence of the Water is the Cause why the Stone or Bullet makes so small a progress therein so is the small Resistence of the Aer the Cause why they both pervade so great a space therein And thus is it Demonstrable that the Resistence of the superior Aer is the External Agent which constantly resisteth by degrees refracteth and at length wholly overcomes the imprest Force whereby Heavy Bodies are violently elevated up into the Aer The Difficulty remaining therefore doth only concern the Impellent Cause of their Fall Down again or whether the Aer besides the force of Resistence hath also any Depulsive Faculty which being imprest upon a stone bullet or other ponderous body at the top or highest point of its mountee serveth to turn the same Downward and afterward to continue its perpendicular descent till it arrive at and quiesce on the Earth Which indeed seems well worthy our Doubt because it is observable that Walls Pavements and the like solid and immote Bodies though they strongly resist the motion of bodies impinged against them doe not yet impress any Contrary motion thereupon the Rebound of a Ball or Bullet from a Wall being the effect meerly of the same force imprest upon it by the Racket or Gun-powder fired which first moved it as is evident even from hence that the Resilition of them to greater or less distance is according to the more or less of the Force imprest upon them Which those Gunners well understand who experiment the strength of their Powder by the greatness of the bullets rebound from a Wall And to solve this Difficulty we must distinguish betwixt Bodies that are devoid of Motion and which being distracted have no faculty of Restitution whereby to recollect their dissociated particles and so repair themselves of which sort are Walls Pavements c and such bodies that are actually in motion and which by reason of a natural Elater or Spring of Restitution easily and speedily redintegrate themselves and restore their severed parts to the same contexture and tenour which they held before their violent distraction to which classis the Aer doth principally belong Now concerning the First sort what we object of the non-impression of any Contrary motion upon Bodies impinged against them is most certainly true but not concerning the Latter For the Arm of a Tree being inflected doth not only resist the inflecting force but with such a spring return to its natural site as serveth to impel any body of competent weight that shall oppose its recurse to great distance as in the discharge of an Arrow from a Bow Thus also the Aer though otherwise unmoved may be so distracted by a Body violently pervading it as that the parts thereof urged by their own native Confluxibility the Cause of all Elaterical or Restorative Motion must soon return to their natural tenour and site and not without a certain violence and so replenish the place formâ—rly possest but now deserted by the body that distracted them Thâ—â— there is so powerful a Restorasive faculty in the Aer as we here â—ssume innumerable are the Experiments those especially by Philosophers usually alledged against a Vacuum Coacervate which attest However that you may the less doubt of its having some and a considâ—rable force of propelling bodies notwithstanding it be Fluid in so high a degree be pleased only to reflect your thoughts upon the great â—orce of Winds which tear up the deepest and firmest rooted Cedars â—â—om the ground demolish mighty Castles overset the proudest Câ—â—racts and rowle the whole Ocean up and down from shoar to shoâ—â— Consider the incredible violence wherewith a Bullet is discharged from a Wind-Gun through a firm plank of two or three inches thickness Consider that no effect is more admirable than that a very small quantity of Flame should with such prodigious impetuosity drive a Bullet so dense and ponderous from a Cannon through thâ— Gates of a City and at very great distance and yet the Flame 〈◊〉 the Gunpowder is not less but more Fluid than Aer Who without the certificate of Experience could believe that meerly by the force of so little Flame a substance the most Fluid of 〈◊〉 that we know not onely so weighty a Bullet should be driven with such pernicity forward through the aer to the distance of many furlongs but also that so vast a weight as a Cannon and its Carriage bear should at the same time be thereby driven backwards or made to recoyle What therefore will you say if this could not come to pass without the concurrence of the Aer For it seems to be effected when the Flame at the instant of its Creation seeking to possess a more ample room or space doth convâ—â— its impetus or violence as well upon the breech or hinder part 〈◊〉 the Canon as upon the bullet lying before it in the bore or 〈◊〉 which discharged through the concave is closely prest upon 〈◊〉 the pursuing flame so that the flame immediately perishing 〈◊〉 leaving a void space the Aer from the front or adverse part instaâ—â— rusheth into the bore and that with such impetuous pernicity 〈◊〉 it forceth the Cannon to give back and yeilds a Fragor or Report as loud as Thunder nay by the Commotion of the vicine Aer 〈◊〉 â—â—akes even the largest structures and shatters Glass-windows 〈◊〉 in the sphere of its violence And all meerly from the 〈◊〉 Motion of the Aer restoring its distracted parts to their nâ—â—ural tenour or Laxity so that you may be satisfied of its Capacity not only to resist the Ascent of a stone thrown upward but also of Depelling it downward by an imprest Motion Notwithstanding our conquest of the main body of this Difficulty abouâ— the Restorative Motion of the Aer we are yet to encounter 〈◊〉 formidable Reserve which consists of these Scruples When a 〈◊〉 is thrown upward doth not the Aer in each degree of 〈◊〉 ascent suffer a Distraction of its parts and so is compelled 〈◊〉 a Periosis or circular motion to succeed into the place left below by the stone Doth it not therefore impress rather an 〈◊〉 than a Depulsive
to some higher Oeconomy thâ—n that according to which she regulates her Common Active and Passive Principles To the SECOND viz. the Influx of Caelestial upon Sublunary Bodies innumerable are the Effects which the Fraud of some the Admiration of many and the Credulity of most have confidently imputed and therefore it cannot be expected we should in this place so much as Enumerate the one Half much less insist upon them All. Sufficient it is to the Acquitance of our praesent Debt that we select the most considerable among them and such as seem Capital and Comprehensive of all the rest As for the Power and Influence of the Stars of which Astrologers talk such wonders and with such pride and ostentâ—tâ—on truly we have Reason to assure us that our Cognation and Subjection to those raâ—iant Bodies is not so great as that not only All the Actions Fortunes and Accidents of Particular men but even the Warres Peace Mutations Subversions of whole Empires Nations States and Provinces should depend upon their Smiles or Frowns as if All Occurrents on the theatre of our Lower Orb were but the orderly and necessary Effects of the Praescriptions and Consignations of the Superior Orbs or as if there were no Providence Divine no Liberty of Mans Will 2 As for the Reciprocation or Afflux and Reflux of the Sea so generally fathered upon the Influx and Motion of the Moon which doth herself suffer the like Ebbs and Floods of her borrowed Light t is well known how Seleucus of old and Galilaeus of late have more fully and roundly deduced it from the motion ascribed to the Earth And though we should allow this great Phaenomenon to depend upon the several Adspects or Phases of the Moon yet is there no necessity to drive us to the subterfuge of any Occult and Immaterial Influence from her waxing and waning Light since the System of Des Cartes in Princip Philoseph part 4. page 22. â— doth much more satisfactorily make it out from the Elliptical Figure of the Sphere wherein the Moon moves as will soon appear to the Examiner 3 As for the Diurnall Expansion and Conversion of the Heliotrope toward the Sun though great notice hath been taken thereof by the Ancients and most of our Modern Advancers of the Vanities of Natural Magick who will have every Plant to retain to some one of the Planets by some secret Cognation and peculiar sympathie have laboured to heighten it to the degree of a Wonder yet can we not conceive the Effect to be so singular nor that any such Solemne Reason need be assigned thereunto For every mans observation may certifie him that all Marygolds Tulippa's Pimpernell Wartwoort Mallow Flowers and indeed most other Flowers so long as they are in their Vigour and Pride use to Open and Dilate toward noon and somewhat Close and recontract themselves after Sun set And the Cause surely is only the Warmth of the Suns Rayes which discussing the Cold and Moisture of the praecedent Night whereby the Leaves were loaden towards the bottom or in the bowle of the Flower and so made to rise more upright and conjoyn their tops and somewhat Exsiccating the Flower make the pedestalls of its leaves more flaccid so that they seem to expand and unfold themselves and incline more outwards meerly by reason of their want of strength to sustain themselves in an erect and concentrical posture for alwayes the hotter the Day the greater is the Expansion Likewise as for the Flowers Conversion to or Confronting the Sun in all its progress above the horizon wherein our Darksom Authors of Magick Natural principally place the Magnale the Cause thereof is so far from being more obscure than that it is the very same with that of its Expansion For as the Sun running his race from East to West doth every moment vary the points of his Rayes vertical incidence upon the stalk which supports the Flower and upon the leaves thereof so must the whole Flower incline its head and wheel about accordingly those parts of the stalk upon which the rayes are more perpendicular and so the heat more intense becoming more dry and flaccid and so less able to support the burthen of the â—â—ower than those which suffer only from the obliâ—nâ— reflected and weaker beams Notwithstanding this Solution if any Champion of secret Magnetism shall yet defend this Circulation to be a 〈◊〉 of the Heliotropâ— to which no other Flower can praetend and that this Solar Plant discovers it Amours to the Sun by not only disclosing its rejoycing head and bâ—som at the praesence and wrapping them up again in the mantle of its owne disconsolate and languishing leaves during the absence of its Lover but also by facing him all day long lest He should insult upon an apprehension that our theory is at a loss we shall tell him in a word that that Propriety which he supposeth must consist only in such a peculiar Contexture and Disposition of the particles which compose its Leaves as makes them more sit to receive and be moved and their spiritual and most subtle parts to be in a manner Circulated by the Rayes of the Sun than the Leaves of any other Flower whatever As in the Organ of Smelling there is a certain Peculiar Contexture of its insensible Component Particles which renders it alone capable of being moved and affected by Odours that have no influence nor activity at all upon the Eye Eare or other Organ of Sense 4 Great things have been spoken also of the Garden Claver which bareth its bosom and hideth the upper part of its stalk whenever the Sun shines hot and bright upon it but this doubtless hath the same Cause as the Former the Hiding of the stalk being nothing but an over-expansion of the Leaves which by reason of the violent ardour of the Sun grow more faint and flaccid and so less able to support themselves 5 A Fifth Secret found in the Catalogue of Caelestial Influxes is the Crowing of the House-Cock at certain and periodical times of night and day and more especially soon after midnight and about day break for most esteem it an Occult Propriety and all our Crollians and such as promote the dreams of Signatures and Sydereal Analogies reckon the Cock a cheif Solar Animal for this reason alone as if his Phansy received some magnetique touches and impressions from the Sun which made him proclame his Aâ—vent into our Hemisphere and like a faithful Watch or Clock measure out the severall stages in its race Great enquiry also hath been made after the Cause hereof in all ages and various Conceptions entertained concerning it Some with lofty and Rhetorical Discourses endevouring to persuade that Nature intended this 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 as Pluâ—arch 〈◊〉 it or Gallicinium as an Alarme to rouse up sluggish man from the dull armes of sleep and summon him to the early Contemplation of her Works as Pliny Natural Histor. lib. 10.
is not every way of Apposition that will be convenient but only that when it is disposed in a direct line respondent to the same Ductus or situation of its Fibres according to which it was continued to the Earth beâ—ore its separation Nor is this meer Conjecture but a truth as firme as the Earth it self and as plain as sense can make it it being constâ—ntly observed that what situation a Loadstone had in its Matrix or minerall bed the very same it shall strongly affect and strictly observe evâ—r after at least while it is a Loadstone i. e. untill time or Fire have destroyed its Verticity And as for the Use thereof it is so â—ruitfull as to yield us the most probable Reason in Generall for sundry the most obscure among all Magneticall Apparences 1 Forasmuch as the Loadstone ever affects its native situation and that its Northern part did while it remained in its matrix adhaere to the Southern parts of the same magnetique vein that lay more North and its Southern part did adhaere to the Northern part of the magnetick vein that lay more South therefore is it that the North pole of a Loadstone doth never affect an union with the North pole of the earth nor its South pole direct to the South pole of the Earth but quite contrary its North pole converts to the South and its South to the North. So that whenever you observe a Loadstone freely swimming in a boate of Cork to convert or decline one of its poles to the North of the Earth you may assure your self that that is the South pole of the Loadstone and è contra 2 From the same and no other Cause is it also that when a Magnet is dissected or broken into two pieces and so two new poles created in each piece the Boreall pole of the one half shall never admit Coition with the Boreall pole of the other nor the Australl extreme of the one fragment affect conjunction wâ—th the Australl extreme of the the other but contrariwise the Australl end shall septentrionate and the septentrionaâ—â— Australize The same also happens whenever â—ny two Loâ—â—stones 〈◊〉 applied each to other the Cause being Generall viz. the Native 〈◊〉 or Grain of the Magnetique Fibres which is inverted wheneâ—â—â— the Boreall part of a Loadstone is applied to the Boreall paâ—t of the Earth or of another Loadstone or the Meridionall part of a Loaâ—stâ—ne be converted to the meridionall part of the Earth of another Loadstone as the Ductus of the Fibres in a shoot of a Plâ—nt is inverteâ— when the upper extreme thereof is inserted into the upper part of a sâ—oâ—k This considered when we observe the Animated Needle 〈…〉 Mariners Compass freely converting it self round upon the pin â—hereon it is aequilibrated that end which directeth to the Norâ—â— pole of the Earth must be the South point of the Needle and viceversally that must be the North cuspis of the Needle which conâ—rontetâ— the South of the Earth And when praesent a Loadstone to a magnetified Versory that part of the Loadstone must be the North pole to which the South cuspis of the Needle comes and that to which the North point of the Needle approaches must be the South of the Loadstone The same also may be concluded of the extremes of Irons when a Loadstone is applied unto them for that part of an Iron barr which laied meridionally hath respected the North must have been spirited by the Southern influence of the Earth and è contra and among our Fire Irons the upper end must have imbibed the Northern influence of the Earth and the Lower the Southern contrary to the assertion of some of our Magneticall Philosophers The NINTH the Analogy of the Earth to the Loadstone and other magnetically inspired bodies being so great and the Cause thereof so little obscure it may seem a justifiable inference That the Terriestriall Globe doth inwardly consist of certain continued Fibres running along from North to South or from South to North in one uninterrupted ductus and consequently that since the middle Fibre is as it were the Axis whose opposite extremes make the two Poles in case the whole Earth could be divided into two or more great parts there would instantly result in every part or division a special Axis two speciall Poles a speciall Aequator and all other conditions as formerly in the whole Globe so that the septentrionall part of one piece would conjoin it self to the Austrine part of another and the septentrionall parts reciprocally avert themselves each from other as the parts of a Loadstone And this we may understand to be that mighty and so long enquired Cause why all the parts of the Terrestriall Globe do so fiâ—mly cohaeâ—e and conserve the primitive Figure the Cohaesion Attractive Virtue constant Direction and spontaneous Verticity of all its genuine parts all whose Southern Fibres doe magnetically or individually conforme and conjoyn themselves to the Northern and their Northern to the Southern being the necessary Causes of that Firmness and constancy of Figure Impossible we confess it is to obtain any ocular Experiment of this constitution of the Earths internall Fibres the very Cortex of the Earth extending some miles in profundity but yet we desume a reasonable Conjecture thereof as well from the great similitude of effects wrought by the Earth and other Magneticks as the Experience of Miners who frequently observe and constantly affirme that the Veins of subterraneous Rocks from whose chinks they dig Iron oare doe allwayes tend from South to North and that the Veins of eminent Rocks which make the Giant Mountains upon the face of the Earth have generally the same Direction And though there are some Rowes or Tracts of Mountains that run from East to West or are of oblique situation yet are there alwayes some considerable intercisures among them from South to North so that that can be no sufficient argument that the interior Fibres of the Earth which are truely and entirely magneticall and subjacent under those Mountainous rocks doe not lye in a meridionall position or conforme to the Axis of the Earth The TENTH that since the observations of Miners ascertain us that the Ranges or Tracts of Rocks in the Cortex or accessible part of the Terrestriall Globe do for the most observe a praecisely Meridionall situation and tend from South to North and sometimes i. e. in some places deâ—lect toward the East and West with less and greater obliquity and that our Reason may from thence and the similitude of the Eâ—rth and Loadstone naturally extract a Conjecture that the Fibres of the Earths Kernell or inaccessible parts though for the most they tend praecisely from the South to the North may yet in many places more and lâ—ss Deflect toward the East and West we need no longer perplex ouâ— minds with enquiring Why all Magnetiques and especially the Versory or Needle of the Sea-mans Compass being horizontally
that we may undo let us first resume our former supposition in the 2. Sect. of our chap. of Gravity and Levity that a stone were situate in any of the Imaginary spaces considering that in that case it could not of it self be moved at all because holding no Communion with the World which you may suppose also to be Annihilated there could be in respect thereof no inferior place or region whereto it might be imagined to tend or fall nor could it have any Repugnancy to motion because there would be no superior region to which it might be conceived to aspire or mount Then let us suppose it to be moved by simple Impulsion or Attraction toward any other part of the Empty or Imaginary spaces and without all doubt it would be moved thitherward with a motion altogether Equal or Uniform in all its parts because there could be no Reason why it should be more slow in some parts of its motion and more swift in others there being no Centre to which it might approach or from which it might be removed Suppose farther that as the stone is in thâ—t motion another Impulse equal in force to the former whereby it was first moved were impressed upon it then assuredly would the stone be moved forward more swiftly than before not by reason of any Affection to tend to any Centre but because the force of the 〈◊〉 impulse persevering the force of the second impulse is superadded unto it and the accession of that force must so corroborate the former as to augment the Velocity of the stones motion And hence comes it that to move forward a boâ—â— already in motion doth not only prolong but accelerate the motion theâ—â—of Imagine moreover that a third impulse were â—â—â—â—ntinentâ—y superadded to the second and then would the motion be yet more swift than before the Encrease of Velocity of necessity still responding to the multiplicity of Impulses made upon the body moved This may be familiar to our conceptions from the Example of a Globe set upon a plane which may be emoved from its place with a very gentle impulse and if many of those Impulses be repeated thickly upon it as it moves the motion thereof will be so accelerated as at length to become superlatively rapid Which also seems to be the Reason why a clay Bullet is discharged by the breath of a man from a Trunck with so great force as to kill a Pidgeon at 20 or 30 yards distance the Impetus or force impelling the bullet growing still greater and greater because in the whole length of the trunck there is no one point in which some of the particles of the mans breath successively flowing do not impress fresh strokes or impulses upon the hinder part of the bullet The same also may be given as the most probable Cause why Long Guns carry or shot or bullet farther than short though yet there be a certain determinate proportion to be observed betwixt the diametre of the bore and the length of the barrel or tube as well in Truncks as Guns experience assuring that a Gun of five foot musket bore will do as good execution upon Fowl with shot and kill as far as one of ten foot and the same bore and consequently that those Gunners are mistaken who desire to use Fowling pieces of above 5 or 6 foot long These considerations premised we may conceive that when a stone first begins to move downward it then hath newly received the first impulse of the magnetique rays emitted from the Earth and that if after the impression of that first impulse the Attraction of the Earth should instantly cease and no nevv force be superadded thereunto from any Cause vvhatever in all probability the stone vvould be carried on tovvard the Earth vvith a very slovv but constantly equal and Uniform pace But because the Attraction of the Earth ceaseth not but is renevved in the second moment by an impulse of equal force to that first vvhich began the stones motion and is again renevved in the third moment in the 4 5 6 c. as it vvas in the second therefore is it necessary that because the former impulses impressed are not destroyed by the subsequent but so united as still to corroborate the first and all combining together to make one great force vve say therefore is it necessary that the motion of the stone from the repeated impulses and so continually multiplied Impetus or Force should be more swift in the second moment than in the first in the third than in the second in the fourth than the third and so in the rest successively and consequently that the Celerity should be Augmented in one and the same tenour or rate from the beginning to the end of the motion The Third thing considerable in this Downward motion of Bodies is the PROPORTION or Rate in which their Celerity is encreased Concerning this we know of no Enquiry at all made by any one of the Ancients only Hipparchus as hath been said thought that in the General the increment of Velocity in things falling down was made in the same reciprocal proportion as the Velocity of the same things projected upward But about 90 yeers past one Michael Varro an eminent Mathematician in tract de motu depending meerly upon Reason would have the Problem to be thus solved What is the Ration or Proportion of space to space the same is the Ration of Celerity to Celerity so that if a stone falling down from the heigth of four fathoms shall in the end of the first fathom acquire one degree of Velocity 〈…〉 â—nd of the second two in the end of the third three in the end of 〈◊〉 fourth four it will be moved twice as swiftly in the end of the second â—athom as in the end of the first thrice as swiftly in the end of the 〈◊〉 and four times as swiftly in the end of the fourthâ— as of the first 〈◊〉 this Proportion is deficient first in this that though the increment of â—â—lerity or of its equal degrees may be compared with the equal moâ—â—nts or parts of space yet can it not be compared also with the equal â—â—ments oâ— parts of Time without which the mystâ—ry can never be 〈◊〉 And therefore Aristotle did excellently well in Defining 〈◊〉 and Slow by Time determining that to be swift which 〈…〉 deal of space in a little time and on the contrary that to be 〈…〉 pervading a little of space in a great deal of time Again 〈…〉 suppose the theorem to be explicable by equal moments of times 〈…〉 such as are the respites or intervals betwixt the pulses of our 〈…〉 and that a stone falling down doth pervade the first fathom of 〈…〉 the first moment then if it pervade the second fathom twice as 〈◊〉 as the first as Varro conceives it must necessarily follow that 〈◊〉 second fathom must be pervaded in the half of a moment if the 〈◊〉 â—hom he percurred thrice as swiftly
ibid. 3 The grand Difficulty of the Cause of the Aers restitution of it self to its natural contexture after rarefaction and condensation satisfyed in brief ibid. CHAP. V. A Vacuum praeternatural p. 35. SECT I. ARTIC 1 WHat is conceived by a Coacervate Vacuity and who was the Inventer of the famous Experiment of Quick-silver in a Glass Tube upon which many modern Physiologists have erected their perswasion of the possibility of introducing it 35 2 A faithful description of the Experiment and all its rare Phaenomena 36 3 The Authors reason for his selection of onely six of the most considerable Phaenomena to explore the Causes of them 37 SECT II. ARTIC 1 THe First Cardinal Difficulty 37 2 The Desert space in the Tube argued to be an absolute Vacuum coacervate from the impossibility of its replâ—tion with Aer ibid. 3 The Experiment praesented in Iconism 38 4 The Vacuity in the Desert Space not praevented by the insinuation of Aether 40 5 A Paradox that Nature doth not abhor all vacuity per se but onely ex Accidenti or in respect to Fluxility ibid. 6 A second Argument against the repletion of the Desert space by Aether 41 7 The Vacuity of the Desert space not praevented by an Halitus or Spiritual Eâ—â—lux from the Mercury for three convincing reasons 42 8 The Authors Apostacy from the opinion of an absolute Coacervate Vacuity in the desert space in regard of ibid. 9 The possibility of the subingression of light ibid. 10 Of the Atoms or insensible bodies of Heat and Cold which are much more exile and penetrative then common Aer 43 11 Of the Magnetical Eâ—â—lux of the Earth to which opinion the Author resigns his Assent 44 12 No absolute plenitude nor absolute Vacuity in the Desert Space but onely a Disseminate Vacuity ibid. SECT III. ARTIC 1 THe second Difficulty stated 45 2 Two things necessary to the creation of an excessive or praeternatural Vacuity ibid. 3 The occasion of Galilaeos invention of a Brass Cylindre charged with a wooden Embol or Sucker and of Torricellius invention of the praesent Experiment ibid. 4 The marrow of the Difficulty viz. How the Aer can be impelled upward by the Restagnant Quick silver when there externally wants a fit space for it to ciâ—culate into 46 5 The solution of the same by the Laxity of the Contexture of the Aer ibid. 6 The same illustrated by the adaequate simile of Corn infused into a Bushel ibid. 7 A subordinate scruple why most bodies are moved through the Aer with so little resistence as is imperceptible by sense 47 8 The same Expeded ibid. 9 A second dependent scruple concerning the Cause of the sensible resistence of the Aer in this case of the Experiment together with the satisfaction thereof by the Gravity of Aer ibid. SECT IV. ARTIC 1 THe State of the Third Difficulty 48 2 The Solution thereof in a Word ibid. 3 Three praecedent positions briefly recognized in order to the worthy profounding of the mystery of the Aers resisting Compression beyond a certain rate or determinate proportion ibid. 4 The Aequiponderancy of the External Aer pendent upon the surface of the Restagnant Mercury in the vessel to the Cylindre of Mercury residuous in the Tube at the altitude of 27 digits the cause of the Mercuries constant subsistence at that point 49 5 A convenient simile illustrating and enforcing the same 50 6 The Remainder of the Difficulty viz. Why the Aequilibrium of these two opposite weights the Mercury and the Aer is constant to the praecise altitude of 27 digits removed ibid. 7 Humane Perspicacity terminated in the exterior parts of Nature or simple Apparitions which eluding our Cognition frequently fall under no other comprehension but that of rational Conjecture ibid. 8 The constant subsistence of the Mercury at 27 digits adscriptive rather to the Resistence of the Aer then to any occult Quality in the Mercury 51 9 The Analogy betwixt the Absolute and Respective Aequality of weights of Quick-silver and Water in the different altitudes of 27 digits and 32 feet 52 10 The definite weights of the Mercury at 27 digits and Water at 32 feet in a Tube of the third part of a digit in diametre found to be neer upon two pound Paris weight ibid. 11 Quaere Why the Aequilibrium is constant to the same point of altitude in a Tube of a large concave as well as in one of a small when the force of the Depriment must be greater in the one then the other 53 12 The solution thereof by the appropriation of the same Cause which makes the descent of two bodies of different weights aequivelox ibid. SECT V. ARTIC 1 THe Fourth Capital Difficulty proposed 54 2 The full solution thereof by demonstration ibid. 3 The same confirmed by the theory of the Cause of the Mercuries frequent Reciprocations before it acquiesce at the point of Aequipondium ibid. SECT VI. ARTIC 1 THe Fifth Principal Difficulty 55 2 Solved by the Motion of Restauration natural to each insâ—nsible particle of Aer ibid. 3 The incumbent Aer in this case equally distressed by two contrary Forces 56 4 The motion of Restauration in the Aerâ—extended to the satisfaction of another consimilar Doubt concerning the subintrusion of Water into the Tube if superaffused upon the restagnant Mercury ibid. 5 A Third most important Doubt concerning the nonapparence of any Tensity or Rigidity in the region of Aer incumbent upon the Restagnant Liquors ibid. 6 The solution thereof by the necessary reliction of a space in the vicâ—â—â— region of Lax aer equal to that which the Hand commoved possesseth in the region of the Comprest 57 7 A confirmation of the same Reason by the adaequate Example of the Flame of a Tapour ibid. 8 2 By the Experiment of Urination ibid. 9 3 By the Beams of thâ— Sun entring a room through some slender crany in the appearance of a White shining Wand and constantly maintaining that Figure notwithstanding the agitation of the aer by wind c. 58 10 4 By the constancy of the Rainbow to its Figure notwithstanding the change of position and place of the cloud and contiguous aer ibid. 11 Helmonts Dâ—lirium that the Rainbow is a supernatural Meteor observed ibid. SECT VII ARTIC 1 THe sixth and last considerable Difficulty ibid. 2 The cleer solution thereâ—â— by the great disproportion of weight betwiâ—t Quick-silver and Water 59 3 A Corollary the Altitude of the Atmosphere conjectured ibid. 4 A second Corollary the desperate Difficulty of conciliating Physiology to the Mathematicks instanced in the much discrepant opinions of Galilaeo and Mersennus concerning the proportion of Gravity that Aer and Water hold each to other ibid. 5 The Conclusion of the Digression and the reasons why the Authorâ—â—â—cribes â—â—â—cribes a Cylindrical Figure to the portion of Aer impendent on the Restagnant Liquors in the Experiment 60 CHAP. VI. Of PLACE p. 62. SECT I. ARTIC 1 THe Identity Essential
Instance in the Visible species of the Foot of a Handworm ibid. 14 By exemplifying in the numerous round Films of Wax successively derepted from a Wax tapor by the flame thereof in the space of an hour and 142 15 In the innumerable Films of Oyl likewise successively delibrated by the flame of an Ellychnium or Match perpendicularly floating in a vessel of equal capacity with Solomons Brazen Sea in the space of 48 hours ibid. 16 By the Analogy betwixt an Odorable and Visible Species ibid. 17 The Manner and Reason of the Production of visible Images according to the hypothesis of Epicurus 143 18 The Celerity of the Motion of visible Images reasoned and compared to that of the Light of the Sun 144 19 The Translation of a moveable from place to place in an indivisible point of time impossible and why ibid. 20 The Facility of the Abduction or Avolation of Images Visible from solid Concretions solved by the Spontaneous Exsilition of their superficial Atoms and the Sollicitation of Light incident upon them ibid. 21 That Objects do not emit their Visible Images but when Illustrated a Conceit though paradoxical yet not improbable 145 SECT II. ARTIC 1 VIsible Images Systatical described and distinguisht from Apostatical ones 146 2 Their Existence assured by the testimony of Diodorus Siculus and ibid. 3 Damascius together with the Autopsy of Kircher ibid. 4 Kirchers Description of that famous Apparition at Rhegium called Morgana Rheginorum and 147 5 Most ingenious Investigation of the Causes thereof ibid. 6 His admirable Artifice for the exhibition of the like aereal Representation in Imitation of Nature 148 CHAP. III. Concerning the Manner and Reason of VISION p. 149. SECT I. ARTIC 1 THe Reason of Vision according to the opinion of the Stoicks 149 2 Of Aristotle 150 3 Of the Pythagoreans ibid. 4 Of Empedocles ibid. 5 Of Plato ibid. 6 Of Epicurus ibid. 7 Of Mons. Des Chartes 151 8 The ingenuity of Des Chartes Conceit acknowledged but the solidity indubitated 152 9 The Opinion of Epicurus more satisfactory then any other because more Rational and less obnoxious to inexplicable Difficulties ibid. 10 The Two most considerable Difficulties opposed to Epicurus position of the Incursion of Substantial Images into the Eye 153 SECT II. ARTIC 1 THat the superfice of no body is perfectly smooth evicted by solid Reason and Autopsie ibid. 2 That the visible Image doth consist of so many Rays as there are points designable in the whole superfice of the object and that each Ray hath its line of Tendency direct respective to the face of that particle in the superfice from which it is emitted 154 3 That the Density and Union of the Rays composing the visible Image is greater or less according to their less or greater Elongation from the Object ibid. 4 That the Visible Image is neither total in the total medium nor total in every part thereof but so manifold as are the parts of the medium from which the object is discernable Contrary to the Aristoteleans 155 5 PARADOX That no man can see the same particle of an object with both Eys at once nay not with the same Eye if the level of its Visive Axe be changed ibid. 6 CONSECTARY That the Medium is not possessed with one simple Image but by an Aggregate of innumerable Images deradiate from the same object all which notwithstanding constitute but one entire Image 156 7 CONSECTARY 2. That Myriads of different Images emanant from different objects may be Coexistent in the Aer without reciprocal penetration of Dimensions or Confusion of particles contrary to the Peripateticks ibid 8 That the place of the visible Images ultimate Reception and complete Perception is the Concave of the Retina Tunica 157 9 That the Faculty forms a judgement of the Conditions of the Object according to the representation thereof by the Image at its impression on the principal part of Vision the Amphiblestroides ibid. 10 CONSECTARY That the Image is the Cause of the Objects apparence of this or that determinate Magnitude 158 11 CONSECTARY 2 That no Image can replenish the Concave of the Retina Tunica unless it be deradiated from an object of an almost Hemispherical ambite 159 12 Why when the Eye is open there is alwayes pourtrayed in the bottom thereof some one Total Image whose various Parts are the Special Images of the several things included in the visual Hemisphere ibid. 13 PARADOX That the prospect of a shilling or object of a small diametre is as great as the Prospect of the Firmament 160 14 Why an object appears both greater in Dimensions and more Distinct in parts neer at hand than far off ibid. 15 Why an object speculated through a Convex Lens appears both greater and more distinct but through a Concave less and more Confused than when speculated only with the Eye 161 16 DIGRESSION What Figur'd Perspicils are convenient for Old and what for Purblind persons 162 17 That to the Dijudication of one of two objects apparently Equal to be really the Greater is not required a greater Image but only an Opinion of its greater Distance 163 18 Des Cartes Opinion concerning the Reason of the Sights apprehending the Distance of an object 164 19 Vnsatisfactory and that for two considerations ibid. 20 And that more solidone of Gassendus viz. that the Cause of our apprehending the Distance of an object consisteth in the Comparation of the several things interjacent betwixt the object and the Eye by the Rational Faculty embraced and corroborated ibid. 21 PARADOX That the same Object speculated by the same man at the same distance and in the same degree of light doth alwayes appear greater to one Eye than the other 165 22 A second PARADOX That all men see distinctly but with one Eye at once contrary to that eminent Optical Axiom that the Visive Axes of both eyâ— concur and unite in the object 166 23 The three degrees of Vision viz. most perfect perfect and imperfect and the verity of the Paradox restrained onely to the two former Degrees 167 SECT III. ARTIC 1 A Research into the Reason of the different Effects of Convex and Concave Glasses as well Dioptrical as Catoptrical ibid. 2 A COROLLARIE Hinting the Causes why an Elliptical Concave reflects the incident rays in a more Acute angle than a Parabolical and a Parabolical than a Spherical 170 3 A CONSECTARY Why a Plane Perspicil exhibits an object in genuine Dimensions but a Convex in Amplified and a Concave in minorated 171 SECT IV. ARTIC 1 A Recapitulation of the principal Arguments precedent and summary of the subsequent 173 2 The Eye Anatomized and the proper use of each Part thereof either absolutely Necessary or onely Advantagious to Vision concisely demonstrated viz. 1 The Diaphanity of the Horny Membrane and the three Humors Aqueous Chrystalline and Vitreous 2 The Convexity of all its parts except the Amphiblestroides 3 The Uvea Tunica and Iris. 4 The Pupilla 5 The Blackness
of the inside of the Uvea Tunica 6 The Tunica Arachnoides 7 The Ciliary Filaments thereof 8 The Chrystalline 9 The Retina Tunica 10 The six Muscles viz. 1 The Direct as the Atollent Depriment Adducent Abducent 2 And Oblique as the 2 Circumactors or Lovers Muscles 173 to 177 3 Why the Situation of an object is perceived by the sight 177 4 The Reason of the eversion of the Image in the Amphiblestroides 178 5 The same illustrate by an Experiment ibid. 6 Why the Motion and Quiet of objects are discerned by the sight ibid. 7 Why Catoptrical Images imitate the motions of their Antitipes or Originals ibid. 8 Why the right side of a Catoptrical Image respects the Left of its Exemplar And why two Catoptrick Glasses confrontingly posited cause a Restitution of the parts of the Image to the natural Form 180 CHAP. IV. The Nature of Colours p. 182. SECT I. ARTIC 1 THe Argument duly acknowledged to be superlatively Difficult if not absolutely Acataleptical ibid. 2 The sentence of Aristotle concerning the Nature of Colours and the Commentary of Scaliger thereupon 183 3 The opinion of Plato ibid. 4 Of the Pythagorean and Stoick 184 5 Of the Spagyrical Philosophers ibid. 6 The reason of the Authors desertion of all these and election of Democritus and Epicurus judgement touching the Generation of Colours ibid. 7 The Text of Epicurus fully and faithfully expounded 185 SECT II. ARTIC 1 A PARADOX That there are no Colours in the Dark 186 2 A familiar Experiment attesting the Verity thereof ibid. 3 The Constancy of all Artificial Tinctures dependent on the constancy of Disposition in the superficial Particles of the Bodies that wear them 187 4 That so generally magnified Distinction of Colours into Inhaerent and meerly Apparent redargued of manifest Contradiction ibid. 5 The Emphatical or Evanid Colours created by Prisms no less Real and Inhaerent than the most Durable Tinctures 188 6 COROLLARY The Reasons of Emphatical Colours appinged on Bodies objected by a Prism 189 7 The true Difference of Emphatical and Durable Colours briefly stated ibid. 8 No Colour Formally inhaerent in objects but only Materially or Effectively contrary to the constant Tenent of the Schools ibid 9 The same farther vindicated from Difficulty by the tempestive Recognition of some praecedent Assumptions of the Atomists 190 SECT III. ARTIC 1 THe Nativity of White or the reason of its perception by the sight 191 2 Black a meer Privation of Light ibid. 3 The Genealogy of all Intermediate Colors ibid. 4 The Causes of the Sympathy and Antipathy of some Colours 192 5 The intermisâ—ion of small shadows among the lines of Light absolutely necessary to the Generation of any Intermediate Colour ibid. 6 Two eminent PROBLEMS concerning the Generation and Transposition of the Vermillion and Caerule appinged on Bodies by Prismes 193 7 The Solution of the Former with a rational Conjecture of the Cause of the Blew apparent in the Concave of the Heavens 194 8 The Solution of the Latter 195 9 The Reasons why the Author proceeds not to investigate the Causes of Compound Colours in Particular 196 10 He confesseth the Erection of this whole Discourse on simple Conjecture and enumerates the Difficulties to be subdued by him who hopes to attain an Apodictical Knowledge of the Essence and Causes of Colours ibid. 11 Des Cartes attempt to dissolve the chief of those Difficulties unsuccessful because grounded on an unstable Hypothesis 197 CHAP. V. The Nature of Light p. 198. SECT I. ARTIC 1 THe Clasp or Ligament of this to the praecedent Chapter ibid. 2 The Authors Notion of the Rays of Light ibid. 3 A Parallelism betwixt a stream of Water exsilient from the Cock of a Cistern and a Ray of Light emanent from its Lucid Fountain ibid PRAECONSIDERABLES 199 4 Light distinguisht into Primary Secondary c. 199 5 All Light Debilitated by Reflection and why ibid. 6 An Example sensibly demomonstrating the same 200 7 That light is in perpetual Motion according to Aristotle ibid. 8 Light why Corroborated in some cases and Debilitated in others by Refraction 201 COROLLARY Why the Figure of the Sun both rising and setting appears rather Elliptical than Sphaerical ibid. 9 PARADOX That the proportion of Solary Rays reflected by the superior Aer or Aether toward the Earth is so small as not to be sensible 202 10 That every Lucid Body as Lucid doth emit its Rays Sphaerically but as Visible Pyramidally ibid. 11 That Light is invisible in the pure medium 203 SECT II. ARTIC 1 THe necessity of the Authors confirmation of the First Praeconsiderable 204 2 The Corporiety of Light demonstrated by its just Attributes viz. 1 Locomotion 2 Resilition 3 Refraction 4 Coition 5 Disgregation 6 Igniety 224 225 3 Aristotles Definition of Light a meer Ambage and incomprehensible 205 4 TheCorporiety of Light imports not the Coexistence of two Bodies in one Place contrary to the Peripatetick 206 5 Nor the motion of a Body to be Instantaneous ibid. 6 The Invisibility of Light in the limpid medium no Argument of its Immateriality as the Peripatetick praesumes ibid. 7 The Corporiety of Light fully consistent with the Duration of the Sun contrary to the Peripatetick 207 8 The insensibility of Heat in many Lucent Bodies no valid Argument against the praesent Thesis that Light is Flame Attenuated ibid. CHAP. VI. The Nature of a Sound p 208. SECT I. ARTIC 1 AN Elogy of the sense of Hearing and the Relation of this and the praecedent Chapter ibid. 2 The great Affinity betwixt Visible and Audible species in their representation of the superficial Conditions of Objects 209 3 In the Causes and manner of their Destruction ibid. 4 In their Actinobolism or Diffusion both Sphaerical and Pyramidal 210 5 In their certifying the sense of the Magnitude Figure and other Qualities of their Originals ibid. 6 In the obscuration of Less by Greater 211 7 In their offence of the organs when excessive ibid. 8 In their production of Heat by Multiplication ibid. 9 In their Variability according to the various disposition of the Medium ibid. 10 In their chief Attributes of Locomotion Exsilition Impaction Resilition Disgregation Congregation ibid. SECT II. ARTIC 1 THe Product of the Praemises concerning the points of Consâ—nt and Dissent of Audible and Visible Species viz That Sounds are Corporeal 213 2 An obstruction of praejudice from the generally supposed repugnant Authorities of some of the Ancients expeded ibid. 3 An Argument of the Corporiety of Sounds 214 4 A Second Argument ibid. COROLLARY ibid. 5 The Causes of Concurrent Echoes where the Audient is equally almost distant from the Sonant and Repercutient ibid. COROLLARY 2. 215 6 Why Concaves yield the strongest and longest Sounds ibid. COROLLARY 3. ibid 7 The reason of Concurrent Echoes where the Audient is neer the 〈◊〉 and remote from the sonant ibid. COROLLARY 4. ibid. 8 Wâ—y 〈◊〉 Monophon rehearse so much the fâ—â—er syllables by how much neerer the audient is
336 8 The Reasons of the vast Ductility or Extensibility of Gold 337 9 Sectility and Fissility the Consequents of Softness ibid. 10 Tractility and Friability the Consequents of Hardness 338 11 Ruptility the Consequent partly of Softness partly of Hardness 339 12 PROBLEM VVhy Chords distended are more apt to break neer the Ends than in the middle and its SOLVT ibid. CHAP. XV. Occult Qualities made Manifest p. 341 SECT I. ARTIC 1 THat the Insensibility of Qualities doth not import their Unintelligibility contrary to the presumption of the Aristotelean ibid. 2 Vpon what grounds and by whom the Sanctuary of Occult Qualities was erected 342 3 Occult Qualities and profest ignorance all one ibid. 4 The Refuge of Sympathies and Antipathies equally obstructive to the advance of Natural Scienee with that of Ignote Proprieties 343 5 That all Attraction referred to Secret Sympathy and all Repulsion adscribed to secret Antipathy betwixt the Agent and Patient is effected by Corporeal Instruments and such as resemble those whereby one body Attracteth or repelleth another in sensible and mechanique operations ibid. 6 The Means of Attractions sympathetical explicated by a convenient Simile 345 7 The Means of Abaction and Repulsions Antipathetical explicated likewise by sundry similitudes 346 8 The First and General Causes of all Love and Hatred betwixt Animals 347 9 Why things Alike in their natures love and delight in the Society each of other and why Unlike natures abhor and avoid each other ibid SECT II. ARTIC 1 THe Scheme of Qualities reputed occult 348 2 Natures Avoidance of Vacuity imputed to the tyzugia or Conspiration of all parts of the Vniverse no Occult Quality ibid. 3 The power and influence of Caelestial Bodies upon men supposed by Judicial Astrologers inconsistent with Providence Divine and the Liberty of mans will 349 4 The Afflux and Reflux of the Sea inderivative from any immaterial Influx of the Moon ibid. 5 The Causes of the diurnal Expansion conversion of the Heliotrope and other Flowers ibid. 6 Why Garden Claver hideth its stalk in the heat of the day 350 7 Why the House Cock usually Crows soon after midnight and at break of day ibid. 8 Why Shell-fish grow fat in the Full of the moon and lean again at the New 352 9 Why the Selenites resembles the Moon in all her several Adspects ibid. 10 Why the Consideration of the Attraction of Iron by a Loadstone is here omitted 353 11 The secret Amities of Gold and Quicksilver of Brass and Silver unridled ibid. 12 A COROLLARY Why the Granules of Gold and Silver though much more ponderous then those of the Aqua Regis and Aqua â—ortis wherein they are dissolved are yet held up and kept floating by them 354 13 The Cause of the Attraction of a Less Flame by a Greater ibid. 14 The Cause of the Involation of flame to Naphtha at distance ibid. 15 Of the Ascention of Water into the pores of a Spunge 355 16 The same illustrated by the example of a Syphon ibid. 17 The reason of the Percolation of Liquors by a cloth whose one end lieth in the liquor and other hangs over the brim of the vessel that contains it 356 18 The reason of the Consent of two Lute-strings that are Aequison ibid. 19 The reason of the Dissent betwixt Lutestrings of sheeps Guts and those of Woolfs â—57 20 The tradition of the Consuming of all Feathers of Foul by those of the Eagle exploded 358 21 Why some certain Plants befriend and advance the growth and fruitfulness of others that are their neighbours ibid. 22 Why some Plants thrive not in the society of some others 359 23 The Reason of the great friendship betwixt the Male and Female Palm-trees 360 24 Why all wines grow sick and turbid during the season wherein the Vines Flower and Bud. 361 25 That the distilled waters of Orange flowers and Roses do not take any thing of their fragrancy during the season of the Blooming and pride of those Flowers as it vulgarly believed ibid. SECT III. ARTIC 1 WHy this Section considers onely some few select Occult Proprieties among those many imputed to Animals 362 2 The supposed Antipathy of a Sheep to a Woolf solved ibid. 3 Why Bees usually invade Froward and Cholerick Persons and why bold and confident men haue sometimes daunted and put to flight Lyons and other ravenous Wild-Beasts 363 4 Why divers Animals Hate such men as are used to destroy those of their own species and why Vermin avoid such Gins and Traps wherein others of their kinde have been caught and destroyed ibid. 5 The Cause of the fresh Cruentation of the Carcass of a murthered man at the presence and touch of the Homicide 364 6 How the Basilisk doth empoyson and destroy at distance 365 7 That the sight of a Woolf doth not cause Hoarsness and obmutescence in the spectator as is vulgarly reported and believed 366 8 The Antipathies of a Lyon and Cock of an Elephant and Swine meerly Fabulous â—67 9 Why a man intoxicated by the venome of a Tarantula falleth into violent fits of Dancing and cannot be cured by any other means but Musick ibid. 10 Why Divers Tarantiacal Persons are affected and cured with Divers Tunes and the musick of divers Instruments 369 11 That the venome of the Tarantula doth produce the same effect in the body of a man as it doth in that of the Tarantula it self and why ibid. 12 That the Venom of the Tarantula is lodged in a viscous Humor and such as is capable of Sounds 371 13 That it causeth an uncessant Itching and Titillation in the Nervous and Musculous parts of mans body when infused into it and fermenting in it ibid. 14 The cause of the Annual Recidivation of the Tarantism till it be perfectly cured 372 15 A Conjecture what kind of Tunes Strains and Notes seem most accommodate to the cure of Tarantiacal Persons in the General ibid 16 The Reason of the Incantation of Serpents by a rod of the Cornus 373 17 DIGRESSION That the Words Spells Characters c. used by Magicians are of no vertue or Efficacy at all as to the Effect intended unless in a remote interest or as they exalt the Imagination of Him upon whom they praetend to work the miracle ibid. 18 The Reason of the Fascination of Infants by old women 374 19 The Reason of the stupefaction of a mans hand by a Torpedo 375 20 That ships are not Arrested in their course by the Fish called a Remora but by the Contrary impulse of some Special Current in the Sea ibid. 21 That the Echineis or Remora is not Ominous 3â—7 22 Why this place admits not of more than a General Inquest into the Faculties of Poysons and Counterpoisons ibid. 23 Poysons defined ibid. 24 Wherein the Deleterious Faculty of poyson doth consist ibid. 25 Counterpoisons defined 378 26 Wherein their Salutiferous Virtue doth consist ibid. 27 How Triacle cureth the venome of Vipers ibid 28 How the body of a
of its resistence becomes aequilibrated to the Mercury at the altitude of 27 dig since the superaffused Water doth no more then advance the Aequilibrium according to the rate of its weight or proportion of resistence Besides it is farther observable that because the Tube is replenished by a 14th part in 27 dig of the altitude above the first Aequilibrium a proportionate access to the Mercury in the Tube being made by a like part of that in the subject vessel impelled into it therefore is the Vacuum above the Mercury in the Tube diminished also by one 14th part and the compression of the Aer impendent on the surface of the restagnant Mercury relaxed and diminished also by a 14th part So that if the vessel underneath the Tube be large enough to admit an addition of Water successively affused until so much of the restagnant Mercury as formerly descended shall be again propelled up into the Tube then must the whole Tube be replenished and so the whole Vacuity disappear for then all Compression of the incumbent aer ceaseth and so much space as was possessed before the Experiment both without and within the Tube by the Mercury Water Aer is again repleted If you shall still insist and urge us to a praecise and definite account of the weight of the Quicksilver contained in the Tube to the altitude of 27 digits and of the Water of 32 feet which makes the Aequilibrium with the opposite weight of the circumstant Aer our Answer is that the exact weight of neither can be determined unless the just Diameter or Amplitude of the Tube be first agreed upon For albeit neither the Longitude nor the Amplitude of the Tube makes any sensible difference in this Phaenomenon of the Experiment the Aequilibrium being still constant to the same altitude of 27 digits for the Mercury and 32 feet for Water yet according as the Cavity of the Tube is either smaller or greater must the weight of the Liquors contained therein be either less or more Since therefore we are to explore the definite weight of the Liquor contained by the determinate Amplitude of the Tube containing suppose we the Diametre of the cavity of the Tube to be one third part of a Digit and we shall find the weight of the Quicksilver from the base to the altitude of 27 digits to be near upon two pound Paris weight and upon consequence the weight of Water in the same Tube of 32 feet in altitude to be the same and the weight of the Cylindre of Aer from its base incumbent on the surface of the restagnant Quicksilver up to its top at the summity of the Atmosphere to be also the same otherwise there could be no Aequilibrium Here as a Corollary we may add that insomuch as the force of a body Attrahent may be aequiparated to the weight of another body spontaneously descending or attracted magnetically by the Earth thereupon we may conclude that the like proportion of weight appended to the handle of the wooden Sucker may suffice to the introduction of an equal vacuum in Galilaeo's Brass Cylindre But perhaps you 'l object that this seems rather to entangle then dissolve the Riddle Since by how much the larger the cavity of the Tube by so much the greater the quantity and so the weight of the Quicksilver contained and by how much the greater the weight or force of the Depriment by so much the more must the Depressed yeild and consequently so much the lower must the Aequilibrium be stated To extricate you from this Labyrinth we retort that the cause of the Aequilibriums constancy to the point of 27 digits whatever be the quantity of the Mercury contained in the Tube is the same with that which makes the descent of two bodies of the same matter but different weights to be Aequally Swift for a bullet of Lead of an ounce falls down as swiftly as one of 100 pound For in respect that a Cylindre of Quicksilver contained in a Tube of a large diametre doth not descend more swiftly then a Cylindre of Quicksilver contained in a Tube of a narrow diametre therefore is it that the one doth not press the bottom upon which as its Base it doth impend more violently then the other doth press upon its Base and consequently the restagnant Quicksilver about the larger Cylindre doth not in its elevation or rising upward more compress the Basis of the impendent Cylindre of Aer then what is restagnant about the lesser Cylindre Whereupon we may conclude that a great Cylindre of Aer resisting a great Cylindre of Quicksilver no less then a small doth resist a small therefore ought the Aequilibrium betwixt the depressure of the Quicksilver and the resistence of the circumstant Aer to be constant to the altitude of 27 digits aswell in a large as a narrow Tube Which reason may also be accommodated to Water and all other Liquors SECT V. The Fourth Capital Difficulty WHy is the deflux of the Quicksilver alwayes stinted at the altitude of 27 digits though in Tubes of different longitudes when it seems more reasonable that according to the encrease or enlargement of the Inanity in the upper part of the Tube which holds proportion to the Longitude thereof the Compression and so the Resistence of the Aer circumpendent ought also to be encreased proportionately and consequently that the Aequilibrium ought to be so much the higher in the Tube by how much the greater Resistence the Aer makes without because by how much a larger Space is detracted from the Aer by so much more diffused and profound must the subingression of its Atomical Particles be and so the greater its resistence Solution Certain it is aswel upon the evidence of sense as the conviction of several demonstrations excogitated chiefly by Mersennus in Phaenom Hydraulic that a Cylindre of any Liquor doth with so much the more force or Gravity impend upon its Base or bottom by how much the higher its perpendicular reacheth or by how much the longer it is and consequently having obtained a vent or liberty of Exsilition below at its Base issues forth with so much the more rapidity of motion And this secret reveals what we explore For according to the same scale of Proportions we may warrantably conceive that by how much the higher the Cylindre of Quicksilver is in the Tube by so much the more forcibly it impendeth upon its Base in the Restagnant Quicksilver and so having obtained a vent below falleth with so much the more rapidity of motion or exsilition thereupon and upon consequence by so much the more violently is the incumbent Aer compressed by the restagnant Quicksilver ascending its resistence overcome and the subingression of its insensible particles into the inane Loculaments of the vicine aer propagated or extended the farther and the space detracted from the Aggregate of Disseminate Inanities so much
the larger and consequently the Coacervate Vacuum apparent in the superior region of the Tube becomes so much the greater And because the Resistence made against the subingression dilating or distending it self is in the instant overcome by reason of a greater impulse caused by the Cylindre of Mercury descending from a greater altitude and that resistence remains which could not be overcome by the remnant of the Mercury in the Tube at the height of 27 digits therefore is this Remaining Degree of resistence the manifest Cause why the Mercury is Aequilibrated here at the point of 27 digits aswell when it falls from a high as a low perpendicular This may receive a degree of perspicuity more from the transitory observation of those frequent Reciprocations of the Quicksilver at the first deflux of it into the restagnant before it acquiesce and fix at the point of Aequiponderancy no otherwise then a Ball bounds and rebounds many times upon a pavement and is by successive subsultations uncessantly agitated up and down untill they gradually diminish and determine in a cessation or quiet The Cause of which can be no other then this that the extreme or remotest subingression of the insensible particles of the Aer is we confess propagated somewhat farther then the necessity of the Aequipondiâ—m requireth by reason of a new access of Gravity in the Quicksilver but instantly the insensible particles of the Aer being so violently and beyond the rate of subingressibility prest upon and made as it were more powerful by their necessary Reflexion then the reâ—idue of Quicksilver remaining in the Tube result back to their former station of liberty with that vehemency as they not only praevent any further subingression and reduce the even-now-superior and conquering force of the Quicksilver to an equality but also repell the Quicksilver delapsed up again into the Tube above the point of the Aequipondium and again when the Quicksilver defluxeth but not from so great an altitude as at first then is the Aer again compelled to double her files in a countermarch and recede from the restagnant Quicksilver though not so far as at first charge And thus the force of each being by reciprocal conquests gradually decreased they come to that Equality as that the Quicksilver subsists in that point of altitude wherein the Aâ—quilibrium is SECT VI. The Fifth Capital Difficulty WHat Force that is whereby the Aer admitted into the lower orifice of the Tube at the total eduction thereof out of the restagnant Quicksilver and Water is impelled so violently as sufficeth not only to the elevation of the remaining Liquors in the Tube but even to the discharge of them through the sealed extreme to a considerable height in the Aer Solution The immediate Cause of this impetuous motion appears to be only the Reflux or Resilition of the so much compressed Basis of the Cylindre of Aer impendent on the surface of the Restagnant Liquors Quicksilver and Water to the natural Laxity of its insensible particles upon the cessation of the force Compressive the Principle and manner of which Restorative or Reâ—lexive Motion may be perspicuously deprehended upon a serious recognition of the Contents of the last Article in the praecedent Chapter of a Disseminate Vacuum and most accommodately Exemplified in the discharge or explosion of a bullet from a Wind-Gun For as the insensible particles of the Aer included in the Tube of a Wind-Gun being by the Embolus or Rammer from a more lax and rare contexture or order reduced to a more dense and close which is effected when they are made more contiguous in the points of their superfice and so compelled to diminish the inane spaces interjacent betwixt them by subingression are in a manner so many Springs or Elaters each whereof so soon as the external Force that compressed them ceaseth which is at the remove of the Diaphragme or Partition plate in the chamber of the Tube reflecteth or is at least reflected by the impulse of another contiguous particle therefore is it that while they are all at one and the same instant executing that Restorative Motion they impel the Bullet gaged in the canale of the Tube before them with so much violence as enables it to transfix a plank of two or three digits thickness So also do the insensible Particles of the Base of the Cylindre of Aer incumbent on the surface of the Restagnant Liquors remain exceedingly compressed by them as so many Springs bent by external Force and so soon as that Force ceaseth the Quicksilver in the Tube after its eduction no longer pressing the Restagnant Mass of Quicksilver underneath and so that by his tumefaction no longer pressing the impendent Aer they with united forces reflect themselves into their natural rare and liberal contexture and in that Restorative motion drive up the remainder of Quicksilver in the canale of the Tube to the upper extreme thereof with such violence as sufficeth to explode all impediments and shiver the glass For in this case we are to conceive the Aer to be aequally distressed betwixt two opposite Forces on one side by the Gravity of the long Cylindre of Aer from the summity of the Atmosphere down to the Base impendent on the superfice of the Restagnant Liquors on the other by the ascendent Liquors in the subjacent vessel which are impelled by the Cylindre of Quicksilver in the tube descending by reason of its Gravity and consequently that so soon as the obex Barricade or impediment of the Restagnant Quicksilver is removed the distressed Aer instantly converteth that resistent force which is inferior to the Gravity of the incumbent aereal Cylindre upon the remainder of the Quicksilver in the Tube as the now more superable Opponent of the two and so countervailing its Gravity by the motion of Reflexion or Restoration hoyseth it up with so rapid a violence as the easily frangible body of the Glass cannot sustain Which Reason doth also satisfie another Collateral Scruple viz. Why Water superaffused upon the Restagnant Quicksilver doth intrude it self as it were creeping up the side of the Tube and replenish the Desert Space therein so soon as the inferior orifice of the Tube is educed out of the Restagnant Quicksilver into the region of Water For it is impelled by the Base of the Aereal Cylindre exceedingly compressed and relaxing it self the resistence of it which was not potent enough to praevail upon the greater Gravity of the Quicksilver in the Tube so as to impel it above the point of Aequiponderancy being yet potent enough to elevate the Water as that whose Gravity is by 13 parts of 14 less then that of the Quicksilver Here the Inquisitive may bid us stand and observe a second subordinate Doubt so considerable as the omission of it together with a rational solution must have rendred this whole Discourse not only imperfect but a more absolute Vacuum i. e.
Regions allowable therein the one Upward from whence without any terminus à quo Atoms flowed the other Dowâ—ward toward which without any terminus ad quem in a direct line they tended So that according to this wild dream any coast from whence Atoms stream may be called Above and any to which they direct their course Below insomuch as He conceited the superfice of the Earth on which our feet find the Centre of Gravity in standing or progression to be one continued plane and the whole Horizon above it likewise a continued plane running on in extent not only to the Firmament but the intire immensity of the Infinite Space According to which Dâ—lirament if several weights should fall down from the firmament one upon Europe another upon Asia a third upon Africa a fourth upon America and their motion be supposed to continue beyond the exteriors of the terrestrial Globe they could not meet in the Centre thereof but would transfix the four quarters in lines exquisitely parallel and still descend at equal distance each from other untill the determination of their motion in the infinite Space by the occurse and resistence of other greater Weighâ—â— For the Declinatory Motion we observe that Epicurus was by a kind of seeming necessity constrained to the Fiction thereof since otherwise He had left his fundamental Hypothesis manifestly imperfect his Principles destitute of a Cause for their Convention Conflictation Cohaerence and consequently no possibility of the emergency of Concretions from them And therefore to what Cicero in â— de fin objects against him viz. that he acquiesced in a supposition meerly praecarious since he could assign no Cause for this motion of Declination but usurped the indecent liberty of endowing his Atoms with what Faculties he thought advantagious to the explanation of Natures Phaenomena in Generation and Corruption we may modestly respond by way of excuse not justification that such is the â—â—becillity of Human understanding as that every Author of a physiological â—abrick or mundane Systeme is no less obnoxious to the same objection of praesuming to consign Provinces for the phrase of Cicero is dare provincias principiis to his Principles then Epicurus For in Concretionâ— or Complex Natures to determine on a reason for this or that sensible Affection is no desperate difficulty since the condition of praeassumed Principles may afford it but concerning the originary Causes of those Affections inhaerent in and congenial to the Principles of those Concretions all we can say to decline a downright confession of our ignorance is no more then this that such is the necessity of their peculiar Nature the proper and germane 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 remaining in the dark to us and so our Curiosity put to the shift of simple Conjecture unless we level our thoughts above Principles and acknowledge no term of acquiescence And even the acute and perspicacious Cicero notwithstanding his reprehension of it in Epicurus is forced to avow the inevitability of this Exigent in express words thus Ne omnes à Physicis irrideamur si dicamus quicquam fieri siâ—e Causa distinguendum est ita dicenaum ipsius Individui hanc esse naturam iâ— pondere gravitate moveatur eamque ipsam esse Caussam cur ita feratur c. Nor is this Crime of consigning provinces to his Principles proper only to Epicurus but common also to the Stoick Peripatetick c. since none of them hath adventured upon a reason of the Heat of Fire the Cold of Water the Gravity of Earth c. Doubtless had Cicero been interrogated Why all the Starrs are not carried on in a motion parallel to the Aequator but some steer their course obliquely why all the Planets travel not through the Ecliptick or at least in a motion parallel thereto but some approach it obliquely the best answer He could have thought upon must have been only this ita Natuâ—ae leges â—erehant which how much beseeming the perspicacity of a Physiologist more then to have excogitated Fundamentals of his own endowed with inhaerent Faculties to cause those diverse tendencies we referr to the easie arbitration of our Reader Concerning the Accidental or Reflex Motâ—on all that is worthy our serious notice is only this that when Epicurus subdivideth this Genus into two species namely 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 ex plaga and 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 ex concussione and affirmeth that all those Atoms which are 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 moved upward pursue both sorts of this Reflex tendency we are not to understand him in this sense that both these kinds of Reflex motion are opposite to the Perpendicular since it is obvious to every man that Atoms respective to their Direct or Oblique incidence in the different points of their superfice may make or rather suffer or direct or oblique resilitions and Epicurus expresly distinguisheth the Motion from Collision or Arietation into that which pointeth upward and that which pointeth sidewayes but in this that he might constitute a certain Generical Difference whereby both the species of Reflex motion might be known from both the species of the Perpendicular For the further illustration of this obscure Distinction and to praevent that considerable Demand which is consequent thereto viz. Whether all the possible sorts of Reâ—â—ex Motion are only two the one directly Upward the other directly Lateral we advertise that Epicurus seems to have alluded to the most sensible of simple Differences in the Pulse of Animals For as Physitians when the Pulsifick Faculty distends the Artery so amply and allows so great a space to the performance of both those successive contrary motions the Diastole and Systole as that the touch doth apprehend each stroke fully and distinctly denominate that kind of Pulse 〈◊〉 and on the contrary when the vibrations of the Artery are contracted into a very little space as well of the ambient as of time so as they are narrow and confusedly praesented to the touch they call it 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 so likewise Epicurus terms that kind of Rebound or Resilition which by a strong and direct incurse and arietation of one Atom against another is made to a considerable distance or continued through a notable interval of space 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 and on the contrary that which is terminated in a short or narrow interval which comes to pass when the resilient Atom soon falls foul upon a second and is thereby reviberated upon a third which repercusseth it upon a fourth whereby it is again bandied against a fifth and so successively agitated until it endure a perfect Palpitation he styles 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Upon this our Master Galen may be thought to have cast an eye when he said lib. de facult nat it was the opinion of Epicurus Omnes attractiones per resilitiones atque implexiones Atomorum fieri that all Attractions were caused by the Resilitions and Implexions of Atoms Which eminent passage in Galen not only
be the segment of a great or small Circle projects the Image of an Object on a paper set at convenient distance from the tube that holds it Confused and insincere because it refracts the rayes thereof even to Disgregation so that never uniting again they are transmitted in divided streams and cause a chaos or perpetual confusion On the Contrary a Convex Lens refracts the rayes before divided even to a Concurse and Union and so makes that Image Distinct and Ordinate which at its incidence thereon was confused and inordinate And so much the more perfect must every Convex Lens be by how much greater the Sphere is of which it is a Section For as Kircher well observes in Magia parastatica if the Lens be not only a portion of a great sphere V. Gr. such a one whose diametre contains twenty or thirty Roman Palms but hath its own diametre consisting of one or two palmes it will represent objects of very large dimensions with so admirable similitude as to inform the Visive Faculty of all its Colours Parts and other discoverables in it superfice Of which sort are those excellent Glasses made by that famous Artist Eustachio Divini at Rome by the help whereof the Painters of Italy use to draw the most exquisite Chorographical Topographical and Prosopographical Tables in the World This Difference betwixt Concave and Convex Perspicils is thus stated by Kircher Art Magnae Lucis Umbrae lib. 10. Magiae part 2. Sect. 5. Hinc patet differentia lentis Conveâ—ae Concavae quod illa confusam speciem acceptam transmissamque semper distinguit optimè ordinat â—lla verò eandem perpetuo confundit unde officium lentis Convexae est easdem confusè accept is in debita distantia secundum suam potentiam distinguere ordinare And by Scheinerus in Fundam Optic lib. 3. part 1. cap. 11. thus Licet in vitro quocunque refractio ad perpendicularem semper accidat quia tamen ipsum superficie cava terminatur radij in aerem egressi potius disperguntur quà m colliguntur cujus contrarium evenit vitro Convexo ob contrariam extremitatem Rationes sumuntur à Refractionibus in diversa tendentibus vitri Convexi Concavi ob contrarias Extremitatum configurationes Concavitas enim radios semper magis divergit sicut Convexitas amplius colligit c. Now to draw these lines home to the Centre of our problem since the Rayes of a Visible Image trajected through a Convex Perspicil are so refracted as to concurr in the Visive Axe it is a clear consequence that therefore an object appears both larger in dimensions and more distinct in parts when speculated through a Convex Glass than when lookt upon only with the Eye because more of the rayes are by reason of the Convexity of its extreme obverted to the object conducted into the Pupil of the Eye than otherwise would have been For whereas some rayes proceeding from those points of the object which make the Centre of the Base of the Visive Pyramid according to the line of Direction incurr into the Pupil others emanant from other parts circumvicine to those central ones fall into the Iris others from other parts circumvicine fall upon the eye-lids and others from others more remote or nearer to the circumference of the Base of the Pyramid strike upon the Eyebrows Nose Forehead and other parts of the face the Convexity of the Glass causeth that all those rayes which otherwise would have been terminated on the Iris eye-lids brows nose forehead c. are Refracted and by refraction deflected from the lines of Direction so that concurring in the Visive Axe they enter the Pupil of the Eye in one united stream and so render the Image imprest on the Retina Tunica more lively and distinct and encreased by so many parts as are the rayes superadded to those which proceed from the parts directly confronting the Pupil On the Contrary because an Image trajected through a Concave Perspicill hath its rayes so refracted that they become more rare and Disgregate the object must therefore seem less in dimensions and more confused in parts because many of those rayes which according to direct tendency would have insinuated into the Pupill are diverted upon the Iris Eyelids and other circumvicine parts of the face Here opportunity enjoyns us to remember the duty of our Profession nor would Charity dispense should we in this place omit to prescribe some General Directions for the Melioration of sight or natively or accidentally imperfect The most common Diminutions of Sight and those that may best expect relief from Dioptrical Aphorisms and the use of Glasses are only Two Presbytia and Myopia The First as the word imports being most familiar to old men is Visus in perspiciendis object is propinquis obscuritas in remotis verò integrum acumen an imperfection of the sight by reason whereof objects near hand appear obscure and confused but at more distance sufficiently clear and distinct The Cause hereof generally is the defect of due Convexity on the outside of the Chrystalline Humor arising either from an Error of the Conformative Faculty in the Contexture of the parts of the Eye or and that mostly from a Consumption of part of the Chrystalline Humour by that Marasmus Old Age which makes the common Base of the Image Visible to be trajected so far inwards as not to be determined precisely in the Centre of the concave of the Retina Tunica And therefore according to the law of Contrariety the Cure of this frequent symptome is chiefly if not only to be hoped from the use of Convex Spectacles which determine the point of Concurse exactly in the Centre of the Retina Tunica the rayes by reason of the double Convexity viz. of the Lens and Chrystalline Humor being sooner and more vigorously united in the due place The Other being Contrary to the first and alwayes Native commonly named Purblindness Physitians define to be Obscuritus visus in cernendis rebus distantibus in propinquis verò integrum acumen a Dimness of the sight in the discernment of Objects unless they be appropinquate to the Eye The Causes hereof generally are either the too spherical Figure of the Chrystalline Humor or in the Ductus Ciliares or small Filaments of the Aranea Tunica the proper investment of the Chrystalline a certain ineptitude to that contraction requisite to the adduction of the Chrystalline inwards towards the retina tunica which is necessary to the discernment of objects at distance either of these Causes making the common Base of the Image to be determined in the Vitrious Humor and consequently the Image to arrive at the retina tunica perturbed and confused And therefore our advice is to all Purblind Persons that they use Concave Spectacles for such prolong the point of concurse untill it be convenient i. e. to the concave of the retina tunica Assumption the Sixth and last Since all objects speculated under the same
Angle seem of equal Magnitude according to that of Scheinerus sicut oculus rem per se parvam magnam arbitratur quia sub magno angulo refractionis beneficio illam apprehendit magnam contrario parvam fundament Optic lib. 2. part 2. cap. 5. and are accordingly judged unless there intervene an Opinion of their unequal Distance which makes the Spectator praesume that that Object is in it self the Greater which is the more Remote and that the Less which is the less Remote therefore to the appehension and Dijudication of one of two objects apparently equal to be really the greater is not required a greater Image than to the apprehension and dijudication of an object to be really the less but only an opinion of its greater Distance This may receive both Illustration and Confirmation from this easie Experiment Having placed horizontally in a valley a plane Looking Glass of no more then one foot diametre you may behold therein at one intuition the Images of the firmament of the invironing Hills and all other things circumsituate and those holding the same magnitude as when speculated directly and with the naked eye and this only because though the Image in Dimensions exceed not the Area of the Glass yet is it such as that together with the things seen it doth also exhibit the Distance of each from other Exactly like a good Landskip wherein the ingenious Painter doth artificially delude the eye by a proportionate diminution and decurtation of the things praesented insinuating an opinion of their Distance And therefore the Reason why the Images of many things as of spacious Fields embroydered with rowes of Trees numerous Herds of Cattle Flocks of Sheep c. may at once be received into that narrow window the Pupill of the eye of a man standing on an Hill Tower or other eminent place advantageous for prospect is only this that to the Speculation of the Hemisphere comprehending all those things in that determinate magnitude is required no greater an Image than to the Speculation of an Hemisphere whose diametre is commensurable only by an inch Since neither more rayes are derived from the one to the Pupil of the Eye than from the other nor to the judication of the one to be so much Greater than the other is ought required beside an Opinion that one is so much more Distant than the other And this we conceive a sufficient Demonstration of the Verity of our last Paradox viz. that the Eye sees as much when it looks on a shilling or other object of as small diametre as when it looks on the greatest Ocean Here most opportunely occurs to our Consideration that notorious PROBLEM Quomodo objecti distantia deprehendatur ab oculo How the Distance of the Object from the eye is perceived in the act of Vision This would Des Cartes have solved 1 By the various Figuration of the Eye Because in the Conspection of Objects remote the Pupil of the Eye is expanded circularly for the admission of more Rayes and the Chrystalline Humor somewhat retracted toward the Retina Tunica for the Determination of the point of Concurse in the same which otherwise would be somewhat too remote and on the contrary in the conspection of objects vicine the Pupil is contracted circularly and the Chrystalline Lens protruded somewhat outwardly for the contrary respects 2 By the Distinct or Confused representation of the object as also the Fortitude or Imbecillity of Light illustrating the same Because things represented confusedly or illustrated with a weak light alwayes appear Remote and on the contrary things praesented distinctly or illustrate with a strong light seem vicine But all this we conceive unsatisfactory 1 Because unless the variation of the Figure of the Eye were Gradual respective to the several degrees of distance intercedent betwixt it and the object it is impossible the sight should judge an object to be at this or that Determinate remotion and that the variation of the Figure of the Eye is not Gradual respective to the degree of distance is evident even from hence that the Pupil of the Eye is as much Expanded and the Lens of the Chrystalline Humor as much Retracted toward the Retina Tunica in the conspection of an object situate at one miles distance as of one at 2 3 4 or more miles there being a certain Term of the Expansion of the one part and Retraction of the other 2 Because though Vision be Distinct or Confused both according to the more or less illustration of the object by light and to the greater or less Distance thereof from the Eye yet doth this Reason hold only in mean not large distance since the orbs of the Sun and Moon appear greater at their rising immediately above the Horizon that is when they are more Remote from the Eye than when they are in the Zenith of their gyre that is when they are more Vicine to the Eye and since all objects illustrate with a weak light do not appear Remote nor â— contra as common observation demonstrateth And therefore allowing the Acuteness of Des Cartes Conceit we think it more safe because more reasonable to acquiesce in the judgment of the grave Gassendus who in Epist. 2. de Apparente Magnitud solis humilis sublimis most profoundly solves the Problem by desuming the Cause of our apprehending the distance of an Object in the act of Vision from a Comparison of the thing interjacent between the object seen and the Eye For though that Comparation be an act of the Superior Faculty yet is the connexion thereof to the sense necessary to the making a right judgment concerning the Distance of the Visible And most certainly therefore do two things at distance seem to be Continued because they strike the Eye with cohaerent or contiguous Rayes Thus doth the top of a Tower though situate some miles beyond a Hill yet seem Contiguous to the same nay to the visible Horizon and this only because it is speculated by the Mediation of Contiguous Rayes and the Sun and Moon both orient and occident seem to cohaere to the Horizon because though the spaces are immense that intercede betwixt their Orbs and the Horizon yet from those spaces doth not so much as one single Raye arrive at the Eye and those which come to it from the Sun and Moon are contiguous to those which come from the Horizon And hence is it that the Tower Hill and Horizon seem to the sight to be equidistant from the Eye because no other things are interposed at least seen interposed by the comparison of which the one may be deprehended more than the other Besides the distance of the Horizon it self is not apprehended by any other reason but the diversity of things interjacent betwixt it and the Eye for look how much of Space is possessed valleys and lower grounds interjacent so much of Space is defalcated from the distance the sight apprehending all
those things to be Contiguous or Continued whose Rayes are received into the Eye as Contiguous or Continued none of the spaces interjacent affording one raye Of which truth Des Cartes seems to have had a glimpse when in Dioptrices cap. 6. Sect. 15. he conceds objectorum quae intuemur praecedaneam cognitionem ipsorum distantiae melius dignoscendae inservire that a certain praecognition of the object doth much conduce to the more certain dignotion of its Distance And on this branch may we ingraft a PARADOX that one and the same object speculated by the same man in the same degree of light doth alwayes appear greater to one Eye than to the other The truth of this is evincible by the joint testimony of those incorruptible Witnesses of Certitude Experience and Reason 1 Of Experience because no man can make the vision of both his eyes equally perfect but beholding a thing first with one eye the other being closed or eclipsed and then with the other the former being closed or eclipsed shall constantly discover it to be greater in dimensions in the apprehension of one Eye than of the other and Gassendus making a perfect and strict Experiment hereof testifies of himself in Epist. 2. de Apparent Magnitud Solis c. Sect. 17. that the Characters of his Book appeared to his right Eye by a fifth part greater in dimensions though somewhat more obscure than to his left 2 Of Reason because of all Twin Parts in the body as Ears Hands Leggs Testicles c. one is alwayes more vigorous and perfect in the performance of its action than the other Which Inaequality of Vigour if it be not the Bastard of Custom may rightfully be Fathered upon either this that one part is invigorated with a more liberal afflux of Spirits than the other or this that the Orgaganical Constitution of one Part is more perfect and firm than that of the other And therefore one Eye having its Pupill wider or the figure of the Chrystalline more Convex or the Retina Tunica more concave than the other must apprehend an object to be either larger in Dimensions or more Distinct in Parts than the other whose parts are of a different configuration either of these Causes necessitating a respective Disparity in the Action If this sound strange in the ears of any man how will he startle at the mention of that much more Paradoxical Thesis of Ioh. Baptista Porta lib. 6. de Refraâ—tion cap. 1. That no man can see distinctly but with one eye at once Which though seemingly repugnant not only to common persuasion but also to that high and mighty Axiom of Alhazen Vitellio Franc. Bacon Niceron and other the most eminent Professors of the Optiques That the Visive Axes of both eyes concurr and unite in the object speculated is yet a verity well worthy our admission and assertion For the Axes of the Eyes are so ordained by Nature that when one is intended the other is relaxed when one is imployed the other is idle and unconcerned nor can they be both intended at once or imployed though both may be at once relaxed or unimployed as is Experimented when with both eyes open we look on the leaf of a Book for we then perceive the lines and print thereof but do not distinctly discern the Characters so as to read one word till we fix the Axe of one eye thereon and at that instant we feel a certain suddain subsultation or gentle impulse in the Centre of that eye arising doubtless from the rushing in of more spirits through the Optick Nerve for the more efficacious performance of its action The Cause of the impossibility of the intention of both Visive Axes at one object may be desumed from the Parallelism of the Motion of the Eyes which being most evident to sense gives us just ground to admire how so many subtle Mathematicians and exquisite Oculists have not discovered the Coition and Union of the Visive Axes in the object speculated which they so confidently build upon to be an absolute Impossibility For though man hath two Eyes yet doth he use but one at once in the case of Distinct inspection the right eye to discern objects on the right side and the left to view objects on the left nor is there more necessity why he should use both Eyes at once than both Arms or Leggs or Testicles at once And for an Experiment to assist this Reason we shall desire you only to look at the top of your own Nose and you shall soon be convicted that you cannot discern it with both eyes at once but the right side with the right eye and afterward the left side with the left eye and at the instant of changing the Axe of the first eye you shall be sensible of that impulse of Spirits newly mentioned Noâ— indeed is it possible that while your right eye is levelled at the right side of your nose your left should be levelled at the left side but on the contrary averted quite â—rom it because the motion of the eyes being Conjugate or Parallel when the Axe of the right eye is converted to the right side of the nose the Axe of the left must be converted toward the left Ear. And therefore since the Visive Axes of both Eyes cannot Concurr and Unite in the Tipp of the Nose what can remain to persuade that they must Concurr and unite in the same Letter or Word in a book which is not many inches more remote than the Nose And that you may satisfie your self that the Visive Axes doe never meet but run on in a perpetual Parallelism i. e. in direct lines as far distant each from other as are the Eyes themselves having fixed a staff or launce upright in the ground and retreated from it to the distance of 10 or 20 paces more or less look as earnestly as you can on it with your right eye closing your left and you shall perceive it to eclipse a certain part of the wall tree or other body situate beyond it Then look on it again with your left eye closing your right and you shall observe it to eclipse another part of the wall that space being intercepted which is called the Parallaxe This done look on it with both eyes open and if the Axes of both did meet and unite in the staff as is generally supposed then of necessity would you observe the staff to eclipse either both parts of the Wall together or the middle of the Parallaxe but you shall observe it to do neither for the middle shall never be eclipsed but only one of the parts and that on which you shall fix one of your eyes more intently than the other This considered we dare second Gassendus in his promise to Gunners that they shall shoot as right with both eyes open as only with one for levelling the mouth of the Peece directly at the mark with one eye their other must be wholly unconcerned therein nor is
Causes why a Concave Glass whose Concavity consisteth of the segment of an Ellipsis reflecteth the rayes of the Sun in a more Acute Angle and consequently burneth both more vigorously and at greater Distance then one whose Concavity is the segment of a Parabola and why a Parabolical Section reflecteth them in an Angle more Acute and so burneth both at greater distance and more vigorously than the Section of Circle Especally if we familiarize this theory by the accommodation of these Figures Thus have we in a short Discourse not exceeding the narrow limits of a single Article intelligibly explicated the Cause of that so much admired Disparity in the Effects of Plane Convex and Concave Glasses as well Dioptrical or Trajecting the rayes of Light into the Aer beyond them as Catoptrical or Reflecting them back again from their obverted superfice And we ask leave to encrease our Digression only with this CONSECTARY Because the Rayes of Light and the rayes of visible Images are Analogical in their nature and flow hand in hand together into the Eye in the act of Vision therefore is it that to a man using a Plane Perspicil an object alwayes appears the same i. e. equal in dimensions and distinction of parts as it doth to his naked Eye by reason the Angle of its Extreams is the same in the Plane Glass as in the Eye But to a man using a Convex Perspicil an object appears Greater because the Angle of its Extreams is ampliâ—ied and through a Concave Less because the Angle is diminished In like manner the Image of an object reflected from a Plane Mirrour appears the same to the Spectator as if Deradiated immediately or without reflexion from the object it self because the Reflex Angle is equal to the Direct but the Image of an Object Reflected from a Convex Mirrour appears Less because the Angle of its Reflection is less than that of its Direction and from a Concave Greater because the Reflex Angle is greater than the Direct This may be autoptically Demonstrated thus If you admit the Image of a man or any thing else through a small perforation of the wall into an obscure chamber and fix a Convex Lens in the perforation with the Convex side toward the Light you shall admoving your eye thereto at Convenient distance observe the transmitted Image to be Amplified but receiving the Image on a sheet of white Paper posited where your Eye was you shall perceive it to be Minorated the Contrary Effect arising from a Concave Lens posited in the hole with its Concave side toward the Light And this because the Convex Congregating the rayes into the Pupill of the Eye and so making the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 or Apparition Greater for the cause formerly exposited doth also Congregate them on the Paper and therefore the Image cannot appear Contracted or Minorated but on the contrary the Concave Disgregating the rayes from the Pupil and so making the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 or Apparition less in the Retina of the Optick Nerve doth also Disgregate or diffuse them largely on all parts of the Paper and so the Image thereon received cannot but appear much Amplified SECT IV. HItherto we have in some degree of satisfaction explicated the Manner how by the Incursion of substantial Images deraâ—â—ated from the object to the Eye the Visive Faculty comes to apprehend the Colour Figure Magnitude Number and Distance of objects and therefore it remains only to the Complement of our present Designation that we explore the Reasons of the Perception of the Situation Quiet and Motion of objects by the sight To our more perspicuous solution of which notable Difficulty and to the illustration of many passages precedent in the two last Sections it must be confest not only ornamental or advantageous but simply necessary that we here Anatomize the whole Eye and consider the proper Uses of the several parts thereof those especially that are either immediately and primarily instrumental or only secundarily inservient to Vision But because the Axe of the Visive Pyramid is a perpendicular line beginning in the Extrems of the object and ending in the Amphiblestroides had the Eye been nailed or fixt in its orbita we must have been necessitated to traverse the whole Machine of the body for a position thereof convenient to Vision since it can distinctly apprehend no object but what lyes è directo opposite or have had this semi-rational sense whose glory builds on Variety restrained to the speculation of so few things that we should have received more Discomfort from their Paucity than either Information or Delight from their Discernment therefore that we might enjoy a more enlarged Prospect and read the whole Hemisphere over in one momentany act of Vision Nature hath furnished the Eyes with Muscles or Organs of agility that so they may accommodate themselves to every visible and hold a voluntary verlisity to the intended object Parâ—â—ula sic magnum pervisit Pupula Coelum And of these Ocular Muscles there are in Man just so many as there are kinds of Motion 4 Direct and 2 Oblique or Circular all situate within the Orbita and associated to the Optick Nerve and conjoining their Tendons at the Horny Membrane they constitute the Tunica Innomitata so named by Columbus who arrogates the invention thereof to himself though Galen lib. 10. de usu part cap. 2. makes express mention of it The First of the four Direct Muscles implanted in the superiour part of the Eye draweth it Upward whence it is denominated Atollens the Lifter up and Superbus the Proud because this is that we use in Haughty and sublime looks The Second situate in the inferiour part of the Eye and Antagonist to the former stoops the Eye Downward and thence is called Deprimens the Depressor and Humilis the Humble for this position of the eye speaks the Dejection and Humility of the Mind The Third fastned in the Major Canthus or great angle of the Eye and converting it toward the Nose is therefore named Adducens the Adducent and Bibitorius for in large draughts we frequently contract it The Fourth opposite both in situation and office to the former abduceth the Eye laterally toward the Ear and is therefore named Abducens and Indignatorius the scorning muscle for when we would cast a glance of scorn contempt or indignation we contract the Eye towards the outward angle by the help of this muscle If all these Four work together the Eye is retracted inward fixt and immote which kind of Motion Physitians call Motus Tonicus and in our language the Sett or Wist Look Of the â—blâ—que Muscles the First running betwixt the Eye and the tendons of the Second and Third Muscles by the outward angle ascends to the superior part of the Eye and inserted near to the Rainbow circumgyrates the Eye downward The Second and smallest twisted into a long tendon circumrotates the Eye toward
Sound is produced in any part of the whole intermediate space betwixt CD And the Ground These stand upon is the Experience of Cloth which being violently shook in the aer for the excussion of dust doth only then emit a smart sound or Rapp when attaining the extremity of its Flexion it percusseth the superior aer and is in the manner of Sails swelled up by the inferior aer But in this instance and that consimilar one of Coach-whips it is almost evident even to the eye that the Rapp is made only by the Doubling of the Cloth or Chord at the end of their Flexion and therefore we are not convinced that the Concinnous Sound is then begun as these persuade in either C or D the period of each Flexion especially when the Chord in C and D seems rather to quiesce than move and some quiet must intercede betwixt two contrary motions of the same thing 4 But â—nsomuch as all sounds are caused by the Motion of the Aer and the Sound alwayes is loudest where the Motion of the Aer is most rapid 〈…〉 the whole sonorous line or space betwixt C and E the motion of the Aer intercluded is most swift when the Chord returns from C to E therefore doth Mersennus to whose judgment we most incline in this nicety conclude that the Harmonical sound is begun in the beginning of the first Recurse of the Chord from C to E and that it is then of the same Acuteness as are all the subsequent sounds made by the subsequent Recurses because the reason of the First Recurse seems to be the same with that of all the consequent To this some have objected that the sound of the First Recurse is too Expedite and short to be perceived by the Ear since even the Eye incomparably more prompt in the discernment of visibles cannot behold an object whose Apparence or Praesence exceeds not the Duration of the foresaid Recurse of the Chord from the extreme of its flexion C to E which doth scarce endure the â—600 part of a minute But this objection is soon dissolved by Experience which testifieth that if a quill or other impediment be placed some small space beyond E towards D so that the Chord may complete its first Recurse from C to E without interruption then will a sound be created and such as hath sufficient Acuteness though it be scarce momentany in Duration because the frequency of its Recurses is praevented Many other Problems there are concerning the Reasons of Sounds wherewith the insatiate Curiosity of Naturalists hath entertained it self in all ages but among them all we shall take cognizance of only those more eminent ones which as they seem most irreconcilably repugnant to our Theory when proposed so must they much confirm and illustrate the dignity thereof when clearly Dissolved by us without the least contradiction to or apostacy from our Principles assumed Since the unstrained Solution of the most difficult Phaenomenaes by the vertue of any Hypothesis is the best argument of its Verity and excellency above others that fail in their Deduction to remote Particulars PROBLEM 2. Whether may a Sound be created in a Vacuum if any such be in Nature SOLUT. To solve this by many accounted inexplicable Aenigme we need only to have recurse to our long since antecedent Distinction of a Vacuity Disseminate and Coacervate for that once entered our judgment we cannot indubitate that ingenious Experiment of Gaspar Berthius laureat Mathematician at Rome frequently and alwayes with honourable Attributes mentioned by Father Kircher in sundry of his Physicomathematical discourses which sensibly demonstrateth the actual production of a Sound in a Disseminate Vacuity The Experiment is thus made Having praepared a large Concave and almost sphaerical Glass aemulating the figure of a Cucurbite or Cupping-glass fix a small Bell such as is usual in striking Watches of the largest size on one side of the concave thereof and a moveable Hammer or striker at fit distance on the other so as the Hammer being elevated may fall upon the skirts of the Bell and then lute or coement on the Glass firmly and closely that all sensible insinuation of the ambient aer be praevented to one extreme of a Glass Tube of about an inch diametre in bore and 8 or 10 feet in length Then reversing the Tube pour into it a sufficient quantity of Quicksilver or Water to fill both it and the Head exactly This done stop the other extreme of the Tube with your finger or other stopple accommodate to the orifice and after gentle inversion immerge the same to a foot depth in a Vessel of Water and withdraw your stopple that so much of the Quicksilver contained in the Head and Tube as is superior in Gravity to the Cylindre of Aer from the summity of the Atmosphere incumbent on the surface of the Water in the subjacent Vessel may fall down leaving a considerable void Space in the superior part of the Tube Lastly apply a vigorous Loadstone to the outside of the Glass Head in the part respecting the moveable extreme of the Hammer that so by its Magnetical Effluxions transmitted through the incontiguities or minute pores of the Glass and fastned on to its Ansulae or smal Holds it may elevate the same which upon the subduction of its Attrahent or Elevator will instantly relapse upon the Bell and by that percussion produce a clear and shrill sound not much weaker than that emitted from the same Bell and Hammer in open aer Now that there is a certain Vacuity in that space of the Head and Tube deserted by the delapsed Quicksilver is sufficiently conspicuous even from hence that the ambient Aer seems so excluded on all hands that it cannot by its Periosis to borrow Platoes word or Circumpulsion succeed into the room abandoned by the Quicksilver and so redintegrate the solution of Continuity as in all other motions And that this Vacuity is not Total or Coacervate but only Gradual or Desseminate may be warrantably inferred from hence 1 That Nature is uncapable of so great a wound as a Coacervate Vacuity of such large dimensions as we have argued in our Chapter of a Vacuum Praeternatural in the First Book 2 That a Sound is produced therein for since a Sound is an Affection of the Aer or rather the Aer is the Material Cause of a Sound were there no aer in the Desert space there could be no Sound Wherefore it is most probable that in this so great distress ingenious Nature doth relieve herself by the insensible transmission of the most aethereal or subtile particles of the Circumpulsed Aer through the small and even with a microscope invisible Pores of the Glass into the Desert Space which replenish it to such a degree as to praevent a Total though not a Dispersed Vacuity therein and though the Grosser Parts of the extremly comprest Aer cannot likewise permeate the same slender or narrow Inlets yet is that
no impediment to the Creation of a Sound therein because the most tenuious and aethereal part of the aer is not only a sufficient but the sole material of a Sound as we have more than intimated in the 15. Art 2. Sect. of the present Chapter The only Difficulty remaining therefore is only this Why the sound made in the disseminate Vacuity should through the Glass-head pass so easily and imperturbed as to be heard by any in the circumstant space when common Experience certifieth that the Report of a Cannon at the distance of only a few yards cannot be heard through a Glass window into a room void of all chinks or crannies Nor need any man despair of expeding it For whoso considers the extraordinary and inscrutable wayes to which Nature frequently recurrs in cases of extreme Necessity and that the Distress she undergoes in the introduction of this violent Vacuity where her usual remedy the Peristaltick motion or Circumpulsion of the Aer is praevented by the interposition of a Solid is much more urgent than that she is put to in the Compression of the ambient aer by the explosion of Canons where the amplitude of uninterrupted space affords freedome of range to the motion imprest we say whoso well considers these things cannot doubt but that it is much easier to Nature to admit the trajection of the Sound produced in the Disseminate Vacuity through the pores of the Glass-head than the transmission of an External Sound into a close Chamber through a Glass window where is no Concavity for the Corroboration or Multiplication of the Sound and consequently where the impulse is far less respective to the quantity of the aer percussed and the resistence as much greater PROBLEM 3. Whence is it that all Sounds seem somewhat more Acute when heard far off and more Grave near at hand when the Contrary Effect is expected from their Causes it being demonstrated that the Gravity of a Sound ariseth mediately at least from the Tardity and Acuteness from the Velocity of the Motion that createth it and many great Clerks have affirmed that the motion of a Sound is less swift far off from than near to its origine according to that General Law of Motion omnia corpora ab externo mota tanto tardius moventur quanto à suo principio remotiora fuerint SOLUT. No Sound is Really but only Apparently more acute at great then at small distance and the Cause of that semblance is meerly this that every Sound near its origine in regard of the more vehement Commotion and proportionate resistence of the Aer dependent on its natural Elater or Expansory Faculty doth suffer some Obtusion or Flatning which gradually diminishing in its progress or Delation through the remoter parts of the Medium the Sound becomes more Clean Even and Exile and that Exility counterfeits a kind of Acuteness PROBLEM 4. Why doth Cold Water in its effusion from a Vessel make a more full and acute noise than Hot or Warm SOLUT. The substance of Cold Water being more Dense and Compact must be more weighty and consequently more swift in its fall and so the noise resulting from its impulsion of the aer more sharp than that of Hot which being rarefied by the fire or made more lax in the contexture of its particles looseth something of its former weight and so hath a slower descent and in respect of that slowness produceth a weaker and flatter sound And this is also the reason why Iron hot yieldeth not so smart and full a sound as when 't is cold PROBLEM 5. Why is the Lowing of a Calf much more Deep or Base than that of an Oxe Cow or Bull at their standard of growth contrary to all other Animals which have their voices more shrill and acute when they are young than when they are old SOLUT. The Cause of this singularity is found only in the peculiar Constitution of the Larynx of a Calf which is in amplitude equal to and in laxity and moysture much exceeds that of an Oxe Cow or Bull full grown and so Age doth Contract and Harden not ampliate the same as in all other Animals and it is well known that the wideness and laxity of the Asper Artery is the cause of all Grave or Base Voyces PROBLEM 6. Why is a Dissonance more easily discovered by the ear in a Barytonous or Base Voyce or Tone than in an Oxytonous or Treble SOLUT. Because the Barytonous voyce is of a slow Motion and the Oxytonous of a swift and the sence doth ever deprehend that object whose apparence is more durable more clearly and distinctly than that whose apparence is only instantaneous or less lasting CHAP. VII OF ODOVRS SECT I. WHoever is natively deprived of any one sense saith Aristotle in Analyticis is much less capable of any Science than He who hath all five Fingers on the left hand of his soul to use the metaphor of Casserius Placentinus in praefat ad lib. de sens Organ or all the Organs of the sensitive Faculty complete and His reason is that General Canon Nihil est in intellectu quod non prius fuerit in sensu the senses being the Windows through which the soul takes in her ideas of the nature of sensible Objects If so whoever hath any one sense less perfect than the others can hardly attain the Knowledge of the nature of objects proper to that sense and upon consequence the Cognition of the Essence of an ODOURE must be so much more difficult to acquire than that of Visibles and Audibles by how much less perfect the sense of SMELLING is in man than the sight and Hearing And that Man generally is not endowed for we may not with our noble Country man Sir Kenelme Digby charge this imperfection altogether upon the Errors of our Diet because we yet want a Parallel for his Iohn of Liege who being bred savagely among wild beasts in the Forrest of Ardenna could wind his pursuers at as great distance as Vultures do their prey and after his Cicuration or reduction to conversation with men retained so much of the former sagacity of his nose that He could hunt out his absen◠friends by the smell of their footsteps like our Blood-Hounds we say that man is not generally endowed with exquisiteness of smell needs no other eviction but this that He doth not deprehend or distinguish any but the stronger or vehement sorts of Odours and those either very offensive or very Grateful But albeit this difficulty of acquiring the knowledge of the Essence and immediate Causes of Odours hath its origine in the native Imperfection of our sense accommodate to the perception thereof yet hath it received no small advance from the obscurity of our Intectuals the Errors of human judgement and the common Effect thereof the contrary Opinions of Philosophers For however they unanimously decree that the proper object of smelling is an Odour and the adaequate
Thomas Iordanus de pestis phaenomen tr 1. cap 18. and Sennertus out of Nich. Polius in Haemerologia Silesiae in lib. de peste cap. 2. Which prodigious Effects clearly proclaim the mighty energy of their Causes and are manifestoes sufficient that Odours justly challenge to themselves those Attributes which are proper onely to Corporiety nor can ought but downright ignorance expect them from the naked Immaterial Qualities or imaginary Images of the Peripatetick 3 The Manner of the Odours moving or Affecting the Sensory can never be explained but by assuming a certain Commensuration or Correspondency betwixt the Particles amassing the Odour and the Contexture of the Olfactory Nerves or Mammillary Processes of the brain delated through the spongy bone For 1 it is Canonical that no Immaterial can Operate upon a Material Physically the inexplicable activity of the Rational Soul upon the body by the mediation of the spirits and that of Angelical essences excepted 2 Though an Odour diffused through the aer chance to touch upon the hands cheeks lips tongue c. yet doth it therein produce no sensation of it self because the Particles of it hold no proportion to either the pores or particles of which those parts are composed but arriving at the organ of smelling it cannot but instantly excite the Faculty therein resident to an actual sensation or apprehension of it in regard of that correspondency in Figure and Contexture which the particles of it hold to the pores and particles of the Odoratory Nerves Certainly as the Contexture of the Odoratory Nerves is altogether different from that of the Tongue and so the minute bodies of them as well as the small spaces intercepted among those minute bodies in all points of their superficies not contingent are likewise of a dissimilar configuration from the particles and intercepted vacuola of the Tongue so also is it necessary that the small bodies which commove and affect the Contexture of the Odoratory Nerves be altogether dissimilar to those which commove and affect the contexture of the Tongue since otherwise all objects would be in common and the Distinction of senses unnecessary Now lest we should seem to beg the Quaestion that the sensation is effected in the Odoratory Nerves only by the Figures of the particles of an Odour and that the variety of Odours depends on the variety of impressions made on the sensory respective to their various figures and contextures this is not obscurely intimated in those formerly recited words of Epicurus Molecularum sive Corpusculorum quaedam perturbate ac discrepanter quaedam verò placide ac leniter seu accommodatè se habere ad olfactus sensorium The substance whereof is this that because the particles and Contexture of some Odours are such that they strike the sensory roughly and discordantly to the contexture thereof therefore are they Ingrateful and on the contrary because other Odours have such particles and such contextures as being smooth in Figure strike the sensory gently evenly and concordantly to the contexture thereof therefore are they Grateful and desiderable We might have introduced Plato himself as lighting the tapor to us in this partâ—cular insomuch as He saith in Timaeo that the sweet sort of Odours 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 de mulcere quâ inseritur amicabiliter se habere doth softly stroke and cause a certain blandishment in the sensory but that the kinde of noysom or stinking Odours 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 doth in a manner Exasperate and wound it To this Incongruity or Disproportion betwixt offensive smells and the composure of the Odoratory Nerves the profound Fracastorius plainly alludeth in his proportionalitèr autem se habent odores quorum ingratissimus est qui Fâ—tidus appellatur quique abominabili in saporibus respondet nam hic ex iis pariter resultat quae nullam habent digestionem nec rationem mistionis sed confusionem èmultis fere ac diversis qualia fere sunt Putrescentia in quibus dissoluta mistione evaporatio diversorum contingit de sympath antipath cap. 14 importing withal that the reason why the stink of corrupting Carcasses is of all other most noysom is because the odours effuming from them consist of heterogeneous or divers particles If you had rather hear this in Verse be pleased to listen to that Tetrastich of Lucretius Non simile penetrare putes primordia formâ In nares hominum cum taetra Cadavera torrent Et cum Scena Croco Cilici perfusa recens est Araque Panchaeos exhalat propter odores Upon which we may justly thus descant As the hand touching a lock of wool is pleased with the softness of it but grasping a Nettle is injured by that phalanx of villous stings wherewith Nature hath guarded the leaves thereof so are the Nostrills invaded with the odour of Saffron delighted therewith because the particles of it are smooth in figure and of equal contexture but invaded with the odour of a putrid Carcase they are highly offended because the particles thereof are asper in figure and of unequal contexture and so prick and dilacerate the tender sensory Moreover whereas there is so great variety of individual Tempeâ—aments among men and some have the Contexture of their odoratory Nerves exceeding dissimilar to that of others hence may we well derive 〈◊〉 Cause of that so much admired secret Why those Odours which are not onely grateful but even highly cordial to some persons are most odious and almost poysonous to others Infinite are the Examples recorded by Physicians in this kinde but none more memorable than that remembred by Plutarch lib. 1. advers Coloten of Berenice and a certain Spartan woman who meeting each other instantly disliked and fainted because the one smelt of Butter the other of a certain fragrant Ointment However the rarity of the Accident will not permit us to pass over the mention of a Lady of honor and eminent prudence now living in London who doth usually swoon at the smell of a Rose the Queen of sweets and sometimes feasts her nose with Assa faetida the Devils Turd as some call it than which no favour is generally held more abominable and this out of no Affectation for her wisdom and modesty exclude that praetence nor to prevent Fitts of the Mother for she never knew an Hysterical passion but in others in all her life as she hath frequently protested to me who have served her as Physician many years Again as this Assumption of the Corporiety of an Odour doth easily solve the Sympathies and Antipathies observed among men to particular smells so likewise doth it yield a plain and satisfactory reason why some Brâ—â—t Animals are pleased with those Odours which are extremely hateful to others Why Doggs abhorr the smell of Wine and are so much delighted with the stink of Carrion as they are loath to leave it behind them and therefore tumble on it to perfume their skins therewith Why a Cat so much dislikes
the solidity of his Inference or Conclusion and left us cause to account that sentence much more Canonical That things most manifest to the Sense often prove most obscure to the Understanding For notwithstanding we have the demonstration of our sense that as He and all other Philosophers unanimously assert the Object of the Tasting in General is 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Gustabile yet doe his endeavours afford so dimme a light to our profounder inquisitions as to leave us in the dark of insatisfaction when We come to explore What is the Formal Reason of a Sapour What are the Principles or Material and Efficient Cause thereof and What Relation it bears unto or Manner how it affects the Tongue the prime and adaequate instrument of Tasting Which that we may with due fulness and perspicuity declare it behoveth us to invite your attention to a faithful Summary of His Speculations concerning that Subject Aristotle from whose Text all the Peripateticks have not receded insomuch as in a title as to the particular under debate fixeth the original of a Sapour in a certain Contemperation of three prime Elemental Qualities viz. 1 Terrestrious Siccity 2 Aqueous Humidity 3 Heat The two former as the Material Causes the last as the Efficient to which according to his custome He consigns the masculine and determinative Energy as in this so in all natural productions The necessity or the Concurrence of these three First Qualities to the Generation of a Sapour in any Concretion He inferrs chiefly from hence that Water being in the purity or simplicity of its essence absolutely insipid if percolated through Siccum terrestre adust Earth doth alwayes acquire a Sapidity or Savouriness proportionate to the intense or remiss adustion of the terrestrious material dissolved by and incorporated to it self as is commonly observable in Fountains which become impraegnate or tincted with the sapours of those veins of Earth through whose Meanders and streights they have steered in their long subterraneous voyages and in all Lixivial decoctions or Lees which obtain a manifest Saltness only by transcolation through Ashes the Earthy and adust reliques of compound bodies dissolved by Fire To which He moreover addes that because the Contemperature may be various according to greater or lesser proportion of either of the three ingredients and the Aqueous Humidum united to the Earthy Siccum hath its consistence sometimes participant of Crassitude sometime of Tenuity therefore are not all Sapours alike but different according to the several Gradualities of their respective and specifical Causes And thus much in the General To progress to the brief survey of Particulars it seems requisite that we observe that Galen Avicenna Averrhoes and most Physitians after them have conceived this Theory of Aristotles so firm and impraegnable as they have thereon founded one of their pillars for the invention of Remedies and advanced rules for the Conjectural investigation of the manifest Faculties of Medicaments by the Taste to that end constituting Eight Differences or Generical Distinctions of Sapours viz. 1 Acer which affects the mouth and chiefly the Tongue with a certain acrimony and pungent ardor such as is eminently conspicuous in Pepper Pellitory Euphorbium Cassea lignea Winterian Bark c. It ariseth from a Composition of tenuious dry and hot parts and cannot subsist in a subject of any other constitution 2 Acid or Sharp which likewise penetrateth and biteth the tongue but with some constringency and without any sense of heat such as is deprehended in Vinegre juice of Limons Citrons Woodsorrel Berberies and in some Malacotones and Quinces It results from a Concretion of subtle and dry parts either where the innate heat is resolved by some degree of putrefaction as in Vinegre or where the innate heat is so small as to be inferior to Cold and that associated with extreme siccity as in juice of Limons c. 3 Fat or Luscious which sollicites the Gusts neither with heat nor acrimony but furrs and daubs the mouth with an unctuous lentor or viscidity Such is remarkable in Oyle Olive Oyle of sweet Almonds Wallnuts in Marrow Butter and the Fat 's of Beasts which have no rancidity either acquired by antiquity or natural such as is perceivable in the Fat of Lions Wolves and Tigers and in all Mucilaginous Plants as in Althaea and White Lilly roots c. This hath its production from a thin aereal matter temperate in heat and cold 4 Salt which doth not much calefie but with a sharp and penetring siccity bite the tongue as is observed in the degustation of Common Salt Nitre and among Vegetables chiefly in Rock Sampier This Sapour is also sensible in all Chymical Salts extracted from Bodies by the sequestrating activity of Fire cinefying their dry and terrestrious remains nor is there any Compound in Nature from which pyrotechny may not extract the Calx or proper Salt thereof discernable by the taste And therefore it is manifest that all saltness subsisteth in a matter whose principal ingredients Heat and Siccity are equal 5 Austere which being moderately adstringent doth with some asperity coarctate the particles of the tongue and therefore according to the judgment of the pallate it seems dry and cooling This is more properly called the Crude Sapour as being peculiar to all Fruits during their immaturity as is generally noted in the juice of unripe Grapes green Apricocks Pears Apples Medlars Porcellane c. The substance wherein it consisteth must be equally participant of Earth and Water but where Cold hath the upper hand of Heat 6 Sweet which being not offensive by the unevenness or exuperance of any Quality affects the sense with suavity or delight Such every man knows to be in Sugar Honey Liquorice Iujubes Dates Figgs and in most Fruits after their maturity as also in Manna and in some degree in Milk 7 Bitter the Contrary to Sweet which offending by the asperity and tenuity of its parts doth in a manner corrade and divell the sensory This superlatively discovers it self in Aloes Coloquyntida Rhubarb Wormwood the lesser Centaury Bitter Almonds and the Galls of Animals The matter of it is crass and terrene but adust by immoderate Heat and hence that Galenical Axiome Omne amarum est calidum siccum 8 Acerb or Sower which bordereth upon the Austere or Pontick Sapour being distinguishable from it only by a greater ingratefulness to the sense for it more constringeth and exasperateth all parts of the mouth and so seems more exsiccative and refrigerative It is prodigally perceived in the rind of Pomegranates Galls Sumach Cypress Nuts the Bark of Oak the Cups of Achorns c. It s residence is alwayes in a Composition totally terrene and drye whose languid heat is subdued to inactivity by the superior force of its antagonist Cold. To these some Modern Physitians to whom that Mystagogus or Priest of the Arabian Oracles Fernelius seems to have been the Coryphaeus have superadded a ninth Sapour 〈◊〉
and Contexture of the Particles of his tongue and è contra To which we shall only add that the Reason why to men in Feavers the sweetest things seem bitter is only this that the Contexture of the Particles of the Tongue being altered as well by the intense Heat of the Feaver as the infusion of a Bilious Humour into the pores thereof those things whose Particles being formerly accommodate appeared in the species of sweetness are now become asymbolical and inconvenient to the particles of the tongue and therefore appear Bitter Nor is Aristotles reprehension of Democritus of weight enough to Counter-encline our judgment his chief Objections being rather Sophistical than Solid and so no sooner urged than dissolved His First is of this importance if the particles of Sapid Objects were Figurate according to Democritus Assumption then would the sight as a Sense far more acute in perception deprehend their various Figures rather than the Taste but the Sight doth not discern them Ergo. Which is soon expeded by Answering that it is not in the jurisdiction of one sense to judge of objects proper to another nor is the quaestion about the Figures as they are in themselves i. e. without relation to the sense but as they produce such a determinate Effect on the sensory of which the Tasting is the sole and proper Criterion For Qualities are to be reputed not so much Absolute and constant Realities as simple and Relative Apparencies whose Specification consisteth in a certain Modification of the First General Matter respective to that distinct Affection they introduce upon this or that particular Sense when thereby actually deprehended His Second of this Insomuch as there is a Contrariety among sensible objects of all kinds but none among Figures according to that universally embraced Canon Figuris nihil esse Contrarium if the Diversity of Sapours were derivative from the Diversity of Figures then would there be no Contâ—â—riety betwixt Sapours but Sweet and Bitter are Contraries Ergo. Which is soon detected to subsist upon a Principle meerly precarious for we are yâ—t ignorant of any reason why we should not account an Acute Figure the Contrary to an Obtuse a Gibbous the opposite to a Plane a Smooth the Antagonist to a Rough an Angular the Antitheton to a Sphere c. His Third and most considerable of this Because the variety of Figures is infinite at least inassignable therefore would the variety of Sapours if their distinct species were dependent on the distinct species of Figures be aequally infinite but all the observable Differences of Saâ—ours exceed not the number of Eight at most Ergo. Answer should we allow Aristotles distinction of Sapours to be genuine yet would it not follow that therefore there are no more Specifical Subdivisions of each Genus because from the various commistions of those Eight Generical Differences one among another an incomprehensible variety of Distinct Sapours may be produced Besides is not that Sweetness which the tongue perceives in Hony manifestly different from that of Milk that of Sugar easily discernable from both that of Canary Sack different from that of Malago that of an Apple distinguishable from that of a Plumm that of Flesh clearly distinct from all the rest yet doth that Genus of Sweet comprehend them all On the other side is the Amaritude of Aloes Coloquyntida Rhubarb Wormwood c. one and the same or the Acerbity of Cherries Prunes Medlars c. identical no man certainly dares affirm it Why therefore should we not write our names in the Catalogue of those who conceive as great variety of Tastes as there is of Sapid objects in Nature Or since the Experiments of Chymistry have made it probable that all Sapours derive themselves from Salts as from their Primary Cause why may we not concede so many several sorts of salts and so many possible Commistions of them as may suffice to the production of an incomprehensible variety of Sapours And this gives us occasion to observe that Nature seems to have furnished the Tonge with a certain peculiar Moisture chiefly to this end that it might have a General Menstruum or Dissolvent of its own for the eduction of those Salts from hard and drye bodies and the imbibition of them into its spongy substance that so it might deprehend and discern them CHAP. IX Of Rarity Density Perspicuity Opacity SECT I. HAving thus steered through the deepest Difficulties touching the proper objects of the other Senses the Chart of Method directs us in our next course to profound the particular natures of all those Qualities which belong to the apprehensive jurisdiction of the Sense of TOUCHING either immediately or relatively But before we weigh Anchor that we may avoid the quicksands of too General Apprehensions and draw a Map or Scheme of all the Heads of our intended Enquiries thaâ— so we may praepare the mind of our Reader to accompany us the more easily and smoothly it is requisite that we advertise 1 That the Attribute of Touching is sometimes in Common to all Bodies 〈◊〉 well Inanimate as Animate when their superficies or extremes arâ— Contingent according to that Antithesis of Lucretius Tactus Corporibus cunctis intactus Inani Sometimes in Common to all Sensâ—â— insomuch as all Sensation is a kind of Touching it being necessaâ—â— that either the object it self immediately or some substantial Emâ—nation from it be contingent to the Sensory as we have apodictically declared in our praecedent considerations of Visible Audible Odoâ—â—ble and Gustable Species Sometimes and in praesent Proper to thâ— Sense of Touching in Animals which however it extend to the Perâ—â—ption of Objects in number manifold in nature various and frequâ—â—â—ly even repugnant whereupon some Philosophers have contumaâ—iously contended for a Plurality of Animal Touchings others gone so high as to constitute as many distinct Powers of Touching as thâ—re are 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Differences and 〈◊〉 of conditions in Tangibles doth yet apprehend them all 〈◊〉 one and the same common reason and determinate qualification after the same manner as the sight discernes White Black Red Green c. all sub communi Coloris ratione in the common capacity of Colours And this is that fertile sense to whose proper incitement we owe our Generation for had not the Eternal Providence endowed the Organs official to the recruit of mankind with a most exquisite and delicate sense of Touching the titillation whereof transports a man beyond the severity of his reason and charmes him to the act of Carnality doubtless the Deluge had been spared for the First age had been the Last and Humanity been lost in the grave as well as innocence in the fall of our first Parents Quis enim per Deum immortalem concubitum rem adeo faedam solicitaret amplexaretur ei indulgeret quo Vultu Divinum illud Animal plenum rationis consilii quem vocamus Hominem obsaenas mulierum partes tot sordibus
the glass doth receive the Reflected rayes with an apparence of many small lights therefore we demand 1 from whence can that species of small shadows arise if not from the Defect of those rayes that are not transmitted through the Glass but averted from it 2 Whence comes it that in neither paper the Brightness or Splendour is so great as when no Glass is interposed betwixt them if not from hence that the reflected rayes are wanting to the nearest the trajected ones to the farthest 3 Whence comes it that some rayes are reflected others trajected if not from hence that as a Lawn sieve transmits those rayes which fall into its pores and repercusseth others that fall upon its threads so doth Glass permit those rayes to pass through that fall into its pores and reverberate those that strike upon its solid particles And what we here say of Glass holds true also in proportion of Aer Water Horn Vernish Muscovy-glass and all other Diaphanous Bodies CHAP. X. OF MAGNITUDE FIGURE And their Consequents SUBTILITY HEBETUDE SMOOTHNESSE ASPERITY SECT I. THe MAGNITUDE and FIGURE of Concretions in regard our Reason doth best derive them from the Two First Proprieties or Essential Attributes of the Universal Matter Atoms are the Qualities which justly challenge our next Meditation Concerning their Origination therefore we advertise First that although it be not necessary that a Body made up of greater Atoms should therefore be greater nor contrariwise that a Body composed of lesser Atoms should therefore be lesser nor that a Body consisting of Atoms of this or that determinate Figure should constantly retain that Figure without capacity of determination to any other yet doth it seem universally true that every Concretion therefore hath Magnitude because its Material Principles or Component Particles have their certain Magnitudes or are essentially endowed with real Dimensions and as true that every Concretion is therefore determined to this or that particular Figure because the Component Particles thereof are not immense or devoyd of circumscription but terminated by some Figure or other Secondly that the term Magnitude here used is not to be accepted in a Comparative intention or as it stands in opposition to Parvity in which sense vulgar ears alwayes admit it but a Positive or as it is identical and importing the same thing with Quantity or Extension For as every Atom or that ultimate and indivisible portion of Matter so called is no Mathematical point but possesseth its own simple Magnitude or Quantity without respect or comparison to Greater or Less So must every Concretion be considered as it stands possessed of its own compound Magnitude or Quantity without respect to any other Body in comparison whereof it may be said to be Greater or Less Because without the relative conception of any other Body the Mind doth most clearly and dictinctly apprehend the Magnitude of a Concretion by a Positive â—otion insomuch it conceives it to have various parts whereof none are included within other but all situate in order and each in its proper place so that from thence must follow the Diffusion of them and consequently the Extension of the whole consisting of them And well known it is that the Magnitude or Quantity of a Body is nothing but that kind of Extension which amounts from the aggregate of the singular Extensions of its component particles of which if any be conceived to be Detracted or Apposed so much is instantly understood to be Detracted from or Apposed to the Extension of the whole Body To this alludes that Distich of Lucretius Propterea quia quae decedunt Corpora quoique â—nde abeunt minuunt quo venere augmine donant This duâ—ly perpended no man need hereafter fear the drilling of his ears by those clamorous and confused litigations in the Schools about the Formal reason of Quantity for nothing can be more evident than this that 〈◊〉 Extension or Quantity of a thing is meerly Moduâ— Materiae or â—ather the Matter it self composing that thing insomuch as it consâ—â—â—eth not in a Point but hath parts posited without parts in respect â—hereof it is Diffuse and purely consequent from thence that every Body hath so much of Extension as it hath of Matter extension â—eing the proper and inseparable Affection of Matter or Substance Hence also may we detect and refute the extreme absurdity of those high-flying Wits who imagine that a Body when Rarified though it hath no more of Matter hath yet more of Quantity or Extension than when Condensed because from the praemises it is an apodictical verity that the Extension attributed to a Body Rarified 〈◊〉 not an Extension of the Matter of it alone but of the Matter and small â—nane Spaces intercepted among its dissociated particles together so that if you suppose the Extension of those small Vacuities to be excluded from the Aggregate you cannot but confess that the Matter hath no more of Extension in its parts Dissociated than it had in the same parts Coaâ—unated Moreover this sufficiently instructs us to give a decisive Response to that so long debated Quaestion An per Rarifactionem acquiratur per Condensationem deperdatur Quantitas Whether the Quantity of a Body is Augmented in Rarifaction and Diminished in Condensation or no For as nothing of Matter is conceived to be added to a body while it is Rarified nothing of Matter detracted from it while Condensed so is it undeniable at least unrefutable that nothing of Quantity is acquired by Rarifaction or amitted by Condensation but only that those empty spaces are admitted or excluded which being in a Rarified body conjoined to the small spaces that the particles of its matter possess make it appear to be Greater or to replenish a greater place than before and in a Condensed body detracted from the small spaces that the particles of its matter do possess make it appear Less or to fill a less place than before If so it may be cause of wonder even to the wisest and most charitable Consideration that the Defendants of Aristotles doctrine of Quantity have with so much labour and anxiety of mind betrayed themselves into sundry not only inextricable Difficulties but open Repugnances while on the one side they affirm that as well Quantity as Matter is Ingenerable and Incorruptible and on the other admit that the same Matter may be one while Extended to the occupation of all and every part of a greater space and another while again so contracted as to be wholly comprehended in the hundreth part of the former space as in the Condensation of Aer into Water than which no Contradiction can be or more open or more irreconcileable And yet we see those who have easily swallowed it and upon digestion become so transcendently exalted to sublimities as to imagine the Quantity of a thing to be absolutely distinct from the matter or substance of it and thereupon to conclude that Rarity and Density doe consist only in the
to prove than impertinent to our praesent scope it being sufficient to the verisimility of our assigned Cause of the perpendicular motion of Terrene Bodies to conceive the Globe of the Earth to be a Loadstone only Analogically i. e. that as the Loadstone â—â—th perpetually emit certain invisible streams of exile particles or Rays of subtle bodies whereby to allect magnetical bodies to an union with it self so likewise doth the Earth uncessantly emit certaâ—n invisible streams or Rays of subtile bodies wherewith to attract all its â—â—stracted and divorced Parts back again to an Union with it self and there closely to detain them And justifiable it is for us to affirm that fâ—â—m the Terraqueous Orbe there is a continual Efflux not only of Vapouâ—s Exhalations and such small bodies of which all our Meteors are composed nor only of such as the general mass of Aer doth consist of but also of otheâ— particles far more exile and insensible nor less subtile than thoâ—e which deradiated from the Loadstone in a moment permeate the most solid Marble without the least diminution of their Virtue Because as the Attractive Virtue of the Loadstone is sufficiently demonstrated by the Effect of it the actual Attraction of Iron unto it so is it lawful for us to conclude the Earth to be endowed with an Attractive Virtue also meerly from the sensible Effect of that Vertue the actual Attraction of stones and all other bodies to it self especially since no other Conception of the Nature of that Affection which the world calls Gravity can be brought to a cleer consistence with that notable Apparence the gradual Encrease of Velocity in each degree of a bodies perpendicular fall Besides the Analogy may be farther deduced from hence that as the Virtue of the Loadstone is diffused in round or spherically and upon consequence its Effluvia or Rays are so much the more rare by how much the farther they are transmitted from their source or original and so being less united become less vigorous in their attraction and at large distance i. e. such as exceeds the sphere of their Energy are languid and of no force at all so doth the Terrestrial Globe diffuse its Attractive Virtue in round and upon consequence its Effluvia or Rays become so much the more rare or dispersed by how much farther they are transmitted from their fountain and so being less united cannot attract a stone or other terrene body at excessive dâ—stance such as the Supralunary and Ultramundane spaces Which that we may assert with more perspicuity let us suppose a stone to be placed in those Imaginary spaces which are the outside of the World and in which God had He so pleased might have created more worlds and then examine whether it be more reasonable that that stone should rather move toward this our Earth than remain absolutely immote in that part of the Ultramandan spaces wherein we suppose it posited If you conceive that it would tend toward the Earth imagine not only the Earth but also the whole machine of the world to be Annihilated and that all those vast spaces which the Universe now possesseth were as absolutely Inane as they were before the Creation and then at least because there could be no Centre and all spaces must be alike indifferent you will admit that the stone would remain fixt in the same place as having no Affecctation or Tendency to this part of those spaces which the Earth now possesseth Imagine the World to be then again restored and the Earth to be resituate in the place as before its adnihilation and then can you conceive that the stone would spontaneously tend toward it If you suppose the Affirmative you will be reduced to inextricable difficulties not to grant the Earth to affect the stone and upon consequence to transmit to it some certain Virtue consisting in the substantial Emanations not any simple and immaterial Quality whereby to give it notice of its being restored to its pristine situation and condition For how otherwise can you suppose the stone should take cognizance of and be moved toward the Earth Now this being so what can follow but that stones and all other Bodies accounted Heavy must tend toward the Earth only because they are Attracted to it by rays or streams of Corporeal Emanations from it to them transmitted Go to then let us farther imagine that some certain space in the Atmosphere were by Power supernatural made so Empty as that nothing could arrive thereat either from the Earth or any other Orbe can you then conceive that a stone placed in that Inanity would have any Tendency toward the Earth or Affectation to be united to its Centre Doubtless no more than if it were posited in the Extramundan spaces because having nothing of Communication therewith or any other part of the Universe the case would be all one with the stone as if there were no Earth no World no Centre Wherefore since we observe a stone from the greatest heighth to which any natural force can elevate the same to tend in a direct or perpendicular line to the Earth what can be more rational than for us to conceive that the Cause of that Tendency in the stone is onely this that it hath some communication with the Earth and that not by any naked or Immaterial Quality but some certain Corporeal though most subtile Emanations from the Earth Especially since the Aer incumbent upon the stone is not sufficient to Begin its motion of Descent If you shall yet withhold your Assent from this Opinion which we have thus long endeavoured to defend we conjecture the Remora to be chiefly this that it seems improbable so great a Bulk as that of a very large stone and that 〈◊〉 such pernicity should be attracted by such slender means as our supposed magnetick Emanations and therefore think it our duty to satisfie you concerning this Doubt We Answer 1 That a very great quantity of Iron proportionately is easily and nimbly rusht into the arms of a Loadstone meerly by Rays of most subtle particles such as can be discovered no way but by their Effect 2 That stones and other massy Concretions have no such great ineptitude or Resistence to motion as is commonly praesumed For if a stone of an hundred pound weight be suspended in the Aer by a small wier or chord how small a force is required to the moving of it hither Why therefore should a greater force be required to the Attraction of it downward 3 When you lift up a stone or other body from the Earth you cannot but observe that it makes some Resistence to your Hand more or less according to the bulk thereof which Resistence ariseth from hence that those many magnetique lines deradiated to and fastned upon it by their several Deflexions and Decussations hold it as it were fast chained down to the Earth so that unless a greater force intervene such as may master the Earth Retentive
the Planets which â—â—â—â—iâ—hstanding the deluded sight are demonstâ—â—ted not to be in onâ— bu◠〈◊〉 sphereâ— somâ— farther â—rom some neâ—râ—â— to the Earth disperâ—e◠〈…〉 immense space For from heâ—ce that thâ— Distance betwixt 〈…〉 uâ— iâ— so vast thâ—t our sight not discerning the large spaces intercepted 〈…〉 them in theâ—â— several orbeâ— they all appeâ—â—e at the same distanc◠〈…〉 same â—ircumâ—â—rence woâ—â— Câ—ntre must be there wherâ— thâ— Eye 〈…〉 selâ— about doth behold them so that in whatsoever part of the 〈◊〉 â—pace oâ— thâ— World whether in the Moon Sun or any otheâ— Orb 〈◊〉 â—hall imaginâ— your selâ— to be placed still you must according to 〈…〉 oâ— your sight judge the World to be spherical anâ— that you 〈◊〉 in the verâ— centre of that Circumference in which you conceive all th◠〈◊〉 stars tâ— be constitute Trul◠〈◊〉 worthy thâ— admiration of a wise man to obserâ—e that the very Planeâ—◠〈◊〉 admitted by the Aristoteleans to have certâ—â—n motions 〈…〉 be moved in such Gyres as have not their Centres in the 〈…〉 immensly distant from it and yet that the same Persons 〈…〉 Contradict thâ—mselveâ— as to account that the Centre oâ— the 〈…〉 common Centre of the world about which all the Coelestâ—al 〈…〉 Difâ—â—culties perpended wâ— cannot infallâ—bl◠〈…〉 Earthy Bâ—â—ieâ— when descending in direct lineâ— to 〈…〉 toward the Centre of the Worâ—d and thougâ— the◠〈…〉 toward the Centre of the World yet doth that seem 〈…〉 is also by Accident that they are carried towaâ—â— the 〈…〉 Earth in which as being a meer imaginâ—ry Point the◠〈…〉 attain quiet For per se they are carried towarâ— the 〈…〉 who le or Principâ—e and having once attained thereâ—◠〈…〉 as they no more seek to pass on from thenc◠〈…〉 â—entre thaâ— an Infant received into his Nurses armes or lap 〈…〉 into heâ— Entrals and meerly per Accidens is it that they 〈…〉 the Centre of the Earth because tending in the neeres◠〈…〉 line to the place oâ— their quiet they must be directed 〈…〉 since if we suppose that direct line to be continued it must 〈…〉 the Centre of the Earth And thus have we left no stone 〈…〉 all Aristotles Theory of Gravity which is that Weight is a Quality esâ—â—ntially inhaerent in all terrene Concritions whereby they spontanâ—ousâ—y 〈◊〉 â—oward the Centre of the Terrestrial Globe aâ— to the Common Cenâ—â—e 〈…〉 place in the Vniverse The whole Remainder of our praesâ—â—◠〈◊〉 theâ—eâ—oâ—e concerns our farther Confirmâ—tion of that 〈…〉 of Gravity which we have espoused which is 〈…〉 meer Effect of the Magnetique Attraction of the Earth Let us therefore once more resume our Argument à Simili considering the Analogy betwixt the Attraction of Iron by a Loadstone and that of Terrene Concretions by the Earth not only as to the Manner of their respective Attractions but cheifly as to the parity of Reasons in our judgements upon their sensible Effects When a man holds a plate of Iron of 6 or 7 ounces weight in his hand with a vigorous Loadstone placed at convenient distance underneath his hand and finds the weight of the Iron to be encreased from ounces to pounds If Aristotle on one side should tell him that that great weight is a Quality essentially inhaerent in the Iron and Kepler or Gilbert on the other affirm to him that that weight is a quality meerly Adventitious or imprest upon it by the Attractive influence of the Loadstone subjacent 't is easie to determine to which of those so contrary judgements he would incline his assent If so well may we conceive the Gravity of a stone or other terrene body to belong not so much to the Body it self as to the Attraction of that Grand Magnet the Terraqueous Globe lying underneath it For supposing that a Loadstone were unknown to you placed underneath your hand when you lifted up a piece of Iron from the earth though it might be pardonable for you to conclude that the great weight which you would observe therein was a Quality essentially inhaerent in the Iron when yet in truth it was only External and Attractitious because you were ignorant of the Loadstone subjacent yet if after you were informed that the Loadstone was placed underneath your hand you should persever in the same opinion the greatest Candor imaginable could not but condemn you of inexcusable pertinacity in an Error Thus also your ignorance of the Earths being one Great Loadstone may excuse your adhaerence to the erroneous position of Aristotle concerning the formal Reason of Gravity but when you shall be convinced that the Terrestial Globe is naturally endowed with a certain Attractive or Magnetique Virtue in order to the retention of all its parts in cohaerence to it self and retraction of them when by violence distructed from it and that gravity is nothing but the effect of that virtue you can have no Plea left for the palliation of your obstinacy in case you recant not your former persuasion Nor ought it to impede your Conviction that a far greater Gravity or stronger Attractive Force is imprest upon a piece of Iron by a Loadstone than by the earth insomuch as a Loadstone suspended at convenient distance in the aer doth easily elevate a proportionate mass of Iron from the earth because this gradual Disparity proceeds only from hence that the Attractive Vertue is much more Collected or United in the Loadstone and so is so much more intense and vigorous according to its Dimensions than in the Earth in which it is more diffused nor doth it discover how great iâ— is in the â—ingle or divided parts but in the Whole of the Earth Thus if you lay but one Grain of salt upon your tongue it shall affect the same with more saltness than a Gallon of Sea-water not that there is less of salt in that great quantity of Sea Water but that the salt is therein more diffused But to lay aside the Loadstone and its Correlative Iron and come to our taste and Incomparative Argument since the Velocity of the motion of a stone falling downward is gradually augmented and by the accession of new degrees of Gravity grows greater and greater in each degree of its Descen◠〈◊〉 that Augmentation or Accession of Gravity and so of Velocâ—â—â— seems noâ— so reasonably adscriptive to any other cause as to this that it is the Attraction of the Earth encreasing in each degree of the stones Appropinquation to the Earth by reason of the greater Density or Union of its Magnetique Rayes What can be more 〈◊〉 than that the First degree of Gravity belonging to a stone no◠〈◊〉 moved should arise to it from the same Attraction of the 〈◊〉 When doubtless it is one and the same Gravity that causeth both those Effects the same in Specie though not in Gradâ—◠〈◊〉 no Quality can be better intended or augmented than by an Accession of more Degrees of force from the same Quality SECT III. LAstly as concerning LEVITY
the accensed matter with such pernicity and vehemence and reciprocal arietations and in such swarms as that they repel the water affused and permit it not to enter the pores of the fewel as constantly happens in Wild-fire where the ingredients are Unctuous and consist of very tenacious particles in that case Water is so far from extinguishing the flame that it makes it more impetuous and raging However we shall acknowledg thus much that if the Principality of Cold must be adscribed to one of the Three vulgar Elements the Aer doubtless hath the best title thereunto because being the most Lax and Porous bodie of the Three it doth most easily admit and most plentifully harbour the seeds of Cold and being also subtile and Fluid it doth most easily immit or carry them along with it self into the pores of other bodies and so not only Infrigidate but some times Congeal and Conglaciate them in case they be of such Contextures and such particles as are susceptible of Congelation and Conglaciation The Fable of the Satyr and Wayfering man who blew hot and cold though in the mouth of every School-boy is yet scarce understood by their Masters nay the greatest Philosophers have found the reason of that Contrariety of Effects from one and the same Cause to be highly problematical Wherefore since we are fallen upon the cause of the Frigidity in the Aer and the Frigidity of our Breath doth materially depend thereon opportunity invites Us to solve that Problem which though both Aristotle sect 3. prob 7. Anaximenes apud Plutarch de frigore primigenio have strongly attempted yet have they left it to the conquest of Epicurus principles viz. Why doth the breath of a man warme when effâ—ated with the mouth wide open and cool when efflated with the mouth contraâ—â—ed To omit the opinions of others therefore we conceive the cause hereof to be only this that albeit the Breath doth consist of aer for the most part fraught with Calorifick Atoms emitted from the lungs and vital organs yet hath it many Frigorifick ones also interspersed among its particles which being of greater bulk than the Calorifick and so capable of a stronger impuls are by the force of efflation transmitted to greatter distance from the mouth because the Calorifick Atoms commixt with the breath in regard of their exility are no sooner dischaged from the mouth than they instantly disperse in round Wence it comes that if the breath be expired in 〈◊〉 large stream or with the mouth wide open because the circuit of the 〈◊〉 of breaâ—h is large and so the Hot Atoms emitted are not so soon dispersed therefore doth the stream feel warme to the hand objected there and so much the more warme by how much neerer the hand is held to the mouth the Calorifick Atoms being less and less Dissipated in each degree of remove But in case the breath be â—mitted with contracted lipps becausâ—â—hen the compass of the stream is small and the force of Efflation greater 〈◊〉 therefore are the Calorifick Atoms soon Disgregated and the Frigorificâ— only râ—main commixt with the Aer which affects the objected hand 〈◊〉 Cold and by how much farther in the limits of the power of Efflation◠〈◊〉 hand is held from the mouth by so much colder doth the breath appear 〈…〉 contra That Calorifick Atoms are subject to more and more 〈…〉 the stream of a Fluid substance to which they are commixt is greater and greater in circuit may be confirmed from hence that if we poure hoâ—â—â—ter from on high in frosty weather we shall observe a fume to issue 〈◊〉 â—scend from the stream all along and that so much the more plentifully by how much greater the stream is Thus we use to cool Burnt wine or 〈◊〉 by frequent refunding it from vessel to vessel or infunding it into broad and shallow vessels that so the Atoms of Heat may be the sooner disperâ—â—â— for by how much larger the superfice of the liquor is made by so much more of liberty for Exsilition is given to the Atoms of Heat containeâ—â—herein and as much of Insinuation to the Atoms of Cold in company 〈◊〉 the circumstant Aer Thus also we cool our faces in the heat of 〈◊〉 with fanning the aer towards us the Hot Atoms being thereby 〈◊〉 and the Cold impelled deeper into the pores of the skin which 〈…〉 the reason why all Winds appear so much the Colder by how much â—â—â—onger they blowe as Deâ—s Cartes hath well observed in these words 〈…〉 vehementior majoris frigiditatis perceptionem quam aer 〈…〉 corpore nostro excitat quod aer quietus tantùm exteriorem nostram 〈…〉 quae interiâ—ribus nostris carnibus frigidior est contingat ventus vero â—â—hementius in corpus nostrum actus etiam in penetralia ejus adigatur 〈◊〉 illa siut cute calidiora id circo etiam majorem frigiditatem ab ejus contaâ—â—â— percipiunt In our preceâ—ent Article touching the necessary assignatin of a Tetrahedical Figure 〈…〉 Atoms of Cold we remember we said that in respect of their 〈…〉 or plane faces they were most apt to Compinge or bind in the particle 〈◊〉 all Concretions into which they are intromitted and from thence we shalâ—â—â—ke the hint of inferring Three noble CONSECTARIES 1. That 〈◊〉 Snow Hail Hoarfrost and all Congelations are made meerly by thâ—â—â—â—romission of Frigorifick Atoms among the particles of 〈…〉 being once insinuated and commixt among them in sufficieâ—◠〈…〉 alter their fluid and lax consistence into a rigid and compact i. e. they Congeal them 2. That 〈…〉 or Trembling sometimes observed in the members of 〈…〉 that Rigor or Shaking in the beginning of most putri◠〈…〉 when the Fits of Intermittent fevers invade are chiefly cause◠〈◊〉 Frigorifick Atoms For when the Spherical Atoms of Heat which swarm in and vivifie the bodies of Animals are not moved quaquaversùm in the members with such freedom velocity and directness excentrically as they ought because meeting and contesting with those less Agile Atoms of Cold which have entred the body upon its chilling their proper motion is thereby impeded they are strongly repelled and made to recoyle towards the Central parts of the bodie in avoydance of their Adversary the Cold ones and in that tumultuous retreat or introcession they vellicate the fibres of the membranous and nervous parts and so cause a kind of vibration or contraction which if only of the skin makes that symptome which Physicians call a Horror but if of the Muscles in the Habit of the bodie makes that more vehement Concussion which they call a Rigor Either of which doth so long endure as till the Atoms of Heat being more strong by Concentration and Union have re-encountered and expelled them That it is of the Nature of Hot Atoms when invaded by a greater number of Cold ones to recoyle from them and concentre themselves in the middle of the body that contains them is demonstrable from the Experiment of Frozen
praestigious and Diabolical For it being certain that all Serpents are most highly offended at the smell and influx of those invisible Emanations proceeding from the Cornus by reason of some great Disproportion or Incompossibility betwixt those subtile Effluviaâ—s and the temperament of the Vital and Spiritual Substance of Serpents insomuch that in a moment they become strongly intoxicated thereby Why should it seem impossible that He who understands this invincible Enmity and how to manage a wand or rod of the Cornus with cunning and dexterity having first intoxicated a Serpent by the touch thereof should during that fit make him observe and readily conforme to all the various motions of that wand So as that the unlearned Spectators perceiving the Serpent to approach the Enchanter as he moves the wand neerer to himself to retreat from him as he puts the wand from him to turne round as the wand is moved round to dance as that is waved to and fro and lye still as in a trance when that is held still over him and all this while knowing nothing that the simple virtue of the wand is the Cause of all those mimical motions and gestures of the Serpent they are easily deluded into a belief that the whole seene is supernatural and the main Energy radicated in those words or Charms which the Impostor with great Ceremony and gravity of aspect mutters forth the better to disguise his Legerdemane and dissemble Nâ—ture in the Colours of a Miracle And as in this so in all other Magical Practices those Bombast Words nonesense Spells exotique Characters and Fanatick Ceremonies used by all Praestigiators and Enchanters have no Virtue or Efficacy at all that little only excepted which may consist meerly in the sounds and tones in which they are pronounced in respect whereof the eare may be pleased or displeased as to the Causation of the Effect intended nor doe they import any thing more than the Circumvention of the Spectâ—â—tors judgement and exaltation of his Imagination upon whom they prâ—etend to work the miracle Which considered it will be an argument not only of Christianism but of sound judgement in any man to conclude that excepting only some few particulars in which God hath been pleased to permit the Devil to exercise his Praestigiatory power and yet whoso shall consider the infinite Goodness of God will not easily be induced to beleive that He hath permitted any such at all all those Volumes of Stories of Fascinations Incantations Transformations Sympathies of men and beasts with Magical Telesms Gamahues or Waxen Images and the like mysterious Nothings are meer Fables execrable Romances So Epidemical we confess hath the Contagion of such Impostures been that among the People when any Person waxeth macilent and pines away we hear of nothing but Evil Neighbours Witchcraft Charms Statues of Wax and the like venefical fopperies and instantly some poor decrepite old woman is suspected and perhaps accâ—â—â—d of malice and Diabolical stratagems against the life of that person who all the while lieth languishing of some Common Disease and the leâ—â—â—ed Physician no sooner examines the case but he finds the sick mans Consumption to proceed from some inveterate malady of the bodie as Ulcer of the Lungs Hectique Fever Debility of the Stomack Liver or other common Concocting part or from long and deep Grief of mind In like manner when the Husband man observes his field to become barren 〈◊〉 chattel â—o cast then yong or die his corn to be blasted his fruits 〈…〉 immaturely or the like sinister Accidents nothing is more usual 〈◊〉 than to charge those misfortunes upon the Magical Impraecations of some offended Neighbour whom the multitude supposeth to be a 〈◊〉 man or Conjurer And yet were the Philosopher consulteâ—â—bouâ— those Disasters he would soon discover them to be the ordinary 〈◊〉 genuine Effects of Natural Causes and refer each Contingent 〈◊〉 proper original True it is likewise that many of those Sorcerers who◠〈◊〉 vulgar call White Witches in respect of the good they 〈…〉 frequently pâ—â—â—scribe certain Amulets or Perâ—apts for the praecentio◠〈…〉 of some diâ—â—ases and in this case if the Amulet or Perâ—apt 〈…〉 such Natural Ingredients as are endowed with Qualitieâ— repugâ—â—â—â— to the Disâ—â—se or its germane Causes we are not to deny 〈…〉 But as for those superstitious Invocations of Angels an◠〈◊〉 Salamons Characters Tetragrammatons Spells Circles an◠〈…〉 and ridiculous Magical Rites and Ceremonies used by the 〈◊〉 at the time of the Composition or Application of those Amulets or 〈◊〉 they are of no power or virtue at all and signifie nothing but 〈◊〉 Delusion of the Ignorant Again we grant that the Imagination 〈◊〉 Confidence of the sick Person being by such means exalteâ— may 〈◊〉 very much to his Recovery for it is no secret that the 〈…〉 men are for the most part erected and their drooping spirit◠〈…〉 by the good opinion they have entertained of the 〈…〉 Confidence they place in his praescripts but yet are 〈…〉 allow any Direct and Natural Efficacy to that 〈…〉 and Ceremonious administration of Remedies which are 〈◊〉 observed by such Impostors as praetend to Extraordinary skill an◠〈◊〉 supernatural way in the Cure of Diseases and seem to affect and 〈…〉 the detestable repute of Magicians And what we say of the 〈…〉 Amulets and the like we desire should 〈…〉 or Love-procuring Potions oâ— the Ligature 〈…〉 Wedding night to cause Impotency in new 〈…〉 then Brides a thing very frequent in Zant and Gascoâ—◠〈…〉 because each of these hath other Causes than those 〈…〉 Nugaments praescribed by those Cheaters and 〈…〉 they can have upon the persons to whom they 〈…〉 in the praepossession of their Phancy and 〈…〉 to Hope or Fear 9 〈…〉 a certain sort of Fascination Natural about which 〈…〉 and most Nurses when they observe 〈…〉 fall into Cachexâ—es languishing condition◠〈…〉 instantly crie out that some envious 〈…〉 them Concerning this secret therefore in 〈…〉 part hath no interest at all we say that if there be any thing of truth as to matter of Fact the Fascinating activity of the old malicious Crone must consist only in this that she doth evibrate or dart forth from her brain certain malignant Spirits or rayes which entering the tender body of the Infant do infect the purer spirits and so the blood in its Arteries and assimilating the same to their depraved and maligne nature corrupt all the Aliment of the body and alienate the parts from their genuine and requisite temperament Not that those Malignant Emissions can arrive at and infect an Infant that is absent as is vulgarly conceived but that the malicious old woman must be praesent and look with an oblique or wist look and breath upon the Child whose health she envies nay conjure up her Imagination to that height of malice as to imbue her spirits with the evil Miasme or Inquinament of those vitious and corrupt Humors wherewith her half-rotten Carcass is well stored and
de marbre blanâ— ave◠〈…〉 Ebubeâ—er Ali Omar Otman Califs successeurs de Maâ—omet 〈…〉 au pres de soy les livres de sa vie de sa Secte 〈…〉 c. And if we consult our own Reason considering the setled 〈…〉 alterable Laws of Magnetical Attraction we shall soon be 〈◊〉 not onely of the monstrous Falsity but absolute Impossibility 〈◊〉 the Effect For should we grant it to be in the power of 〈◊〉 industry to place an Iron so praecisely in the neutral point of the Medium betwixt two Loadstones equally attracting it the one upward the other downward as that the Gravity of the Iron and downward Attraction of the Inferiour Loadstone might not exceed nor be exceeded by the â—pward Attraction of the Superiour Loadstone and so the Iron should remain without any visible support Aequilibrated betwixt them iâ— the Aer yet could not that position of the Iron be of any Duration because upon the least mutation of the temper of the Iron or motion of it by the waving of the Aer from high winds and divers other causes the Aequilibration must cease and the Iron immediately determine it self to the Victor or strongest Attractor But since what is here supposed is wholly repugnant to the Experience of all who have or shall attempt so to aequilibrate an Iron in the Aer betwixt two Loadstones as that it shall not feel the Attractive Virtue of one more strong than that of the other we need not long study what to think of the suspension of Mahomets Iron Chest. Nor is it less impossible that an Iron should be held up at distance in the Aer by the Virtue of a Loadstone placed above it insomuch as that force which at first is sufficient to overcome the resistence of the Irons Gravity and elevate it from the ground must as the Iron approacheth nearer be still more potent to attract it and so that cannot oppose the Attractive Energy of the Loadstone in the middle of it sphere which was forced to submit and conform unto it in the Extremes This we may soon experiment with a Needle by a thread chained to a table and elevated perpendicularly in the aer by the pole of a Loadstone for the Needle will nimbly spring up to meet the Loadstone so farr as the thread will give it scope and if the tâ—read be cut off it instantly quits the medium and unites it self to its Attractor from whose embraces it was before violently detained Hereupon as we may assure our selves that Dinocrates that famous Architect who as Pliny relates lib. 34. cap. 14. began to Arch the Temple of Arsinoe in Alexandria with Loadstones that so Her Iron Statue might remain Pendulous in the aer to excite wonder and Veneration in the Spectators but was interrupted in the middle of his Work both by his own death and that of Ptolomy Arsinoes Brother who expired not long before him died most opportunely in respect of his Reputation because He must have failed of the chief Design though he had lived to finish his structure so also can it be no longer doubted that Ruffinus his story of the Iron Chariot in the Temple of Serapis and Beda's of the Iron Horse of Bellerâ—phon sustained by Loadstones so cunningly posited as that their Virtues concurr and become adjusted in one determinate point are meer Fables and fit to be told by none but doating old women in the chimney corner The FIFTH As one Loadstone is stronger in its Attractive Virtue than another though of the same nay perhaps much greater bulk and weight so is some Iron more disposed than other both to admit and conform to the Attraction of a Loadstone and after invigoration to attract and impraegnate other Iron As for the Vigour and Perfection of a Loadstone it consisteth both in its Native Purity and Artificial Politeness 1 In its Native Purity for if no Dross or Heterogeneous substance be admixt to the Magnetick Vein in the earth from which a Magnet is extracted then is that Loadstone superlatively potent and energetical in Attraction and among Loadstones of this sincere and homogeneous Constitution there are found no degrees of Comparison but what the Difference of their several Bulks doth necessarily create But in case any Heterogeneous matter be commixt with the Magnetick seeds or particles of a Loadstone at its Concretion as it for the most part falls out then must the Attractive Energy of that stone be weaker according to the proportion of that spurious matter admixed thereunto This may be confirmed from hence that some very small Loadstones are more potent than very Great ones of which sort shall we account that of which Mersennus de Magnete affirms that weighing but 7 Gr. in all it would nimbly attract and elevate a mass of Iron 17 times higher than it self and from hence that some stones that were dull and languid before after the secretion of their Drossy and Impure parts become very active and potent Thus when any Heterogeneous substance hath been like a Cortex or shell circumobduced about a Loadstone in its concretion if the same be pared or filed away and the remaining Kernel be polished its Virtue shall be augmented to a very great proportion 2 In its Artificial Tersness or Politeness for by how much smoother a Loadstone is in it superfice with so many the more rayes of Virtue both Attrahent and Amplectent or Connectent doth it touch Iron oblated unto it and è contra Likewise as for the more or less praedisposiâ—ion of Iron both to receive the Attractive influence of a Loadstone and after excitement to attract other iron this also consisteth either in its more or less of Native Purity or of Acquired Politeness because how much the nearer it comes to the pure nature of Steel by so many the more parts hath it both Unitive unto the Loadstone and susceptive of its rayes and by how much more smooth and equal it superfice is made by so many more are the parts by which it doth touch and adhaere unto the Loadstone and consequently imbibe so much the more of its Virtue and è contra And this introduceth The SIXTH OBSERVABLE That a Loadstone being Armed or Capp't with steel is thereby so much Corroborated that it will take up a farr greater weight of Iron or Steel than while it remained naked or unarmed For Mersennus had a Loadstone which as himself avoucheth being naked could elevate no more than half an ounce of Iron but when he had armed it with pure and polisht steel it would easily suspend 320 times a greater weight i. e. ten pounds of Iron a proportion not credible but upon the certificate of Experiment Now the Cause of this admirable Corroboration of the Loadstones Attractive Virtue by a plate of polisht Steel can be no other than this that the Loadstone being of such a rough contexture as that in respect of the particles of some heterogeneous matter concorporated unto it
a stone fall Down again He shall Answer that what moves it Downward per se is the Generant it self or that which first Produced the stone and that which moves it downward per Accidens is that which removes the impediment or obstacle to its descent as the hand of a man or other thing supporting the stone And if you again enquire of him What is the Difference betwixt the Upward and Downward motion of a stone how one should be Violent and the other Natural since according to his own Assertion both are Caused by another His Return will be that the Difference lies in this that the stone is not carried upward of its own Nature but Downward as having the Principle of its Descent inhaerent in it self but not that of its Ascent If you urge Him yet farther since the stone hath in it self the Principle of its Motion why therefore is it not moved only by it self but wants Another or External Motor His Answer will be that there is a Twofold principle of motion the one Active the other Passive and in the stone is only the Principle Passive but in the External Motor is the Active When yet it may be farther pressed that since according to his own Doctrine the Passive principle is the matter and the Active the Forme as to the matter that cannot be the principle of its motion Downward no more than of its motion upward and as for the Forme if that be neither the Active principle nor the Passive as he will by no means admit certainly there can be none Which for Him to allow were plainly to destroy his own great Definition of Nature wherein He acknowledgeth it to be the Principle of Motion But alas these are but light and venial Mistakes in comparison of those gross Incongruities that follow When Aristotle comes to handle the Species or sorts of Natural Motion you may remember that He first Distinguisheth Natural motion in Direct and Circular and then subdistinguisheth the Direct into 1 that which is from the Circumference toward the Centre or from the Extrems toward the middle of the world which He calls Downward and 2 that which is from the Centre toward the Circumference which He calls Upward assigning the former or Downward motion only to Heavy things to the Earth simply to Water and mixt things Secundum quid and the Upward be What then must that External Principle be as Aristotle contends the very Generant of the thing moved Certainly that 's highly Absurd since the Generant is absent and perhaps long since ceased to be in rerum natura and nothing either Absent or Nonexistent can be the Efficient of a Natural Action such as motion is If you will have that to be moved by the Generant signifies no more than to receive a Virtue or Power of moving it self from the Generant then while you endeavour to save Aristotle from the former Absurdity you praecipitate him into a gross Contradiction of his own Doctrine for since the Generant it self ought to be moved by its Generant and that again to be moved by its Generant and so upward along the whole series of Generants till you arrive at length at some First Generant from whence that Virtue was first derived you bring Aristotle to allow a First Generant which impugns his fundamental supposition of the Eternity of the World Nay if you admit God to be the Author of the First Generant it will then follow that God must be the Cause of this particular motion and not the First Generant no more than the Last Finally is that the Cause which only removes the Impediment to a Heavy bodies Descent Neither is that Reasonable for as Aristotle himself confesseth such a Cause is only a Câ—use by Accident Seeing therefore that the Downward motion of a Heavy Body doth not proceed from any Internâ—l Principle nor from either its Generant or that Accidental one which removes the Impediment to its Descent in the supposed Capacity of an External let us proceed to enquire Whether there be not some other External Cause whereupon we may reasonably charge that Effect Which that we may do with the more both of order and plainness it is requisite that we first remember how Philosophers constitute diveâ—s sorts of Violent or Externally-caused motion Empericus â— advers physicos makes 4 distinct species thereof viz. Pulsion Traction Elation Depression And Aristotle sometimes superads a fifth namely Collision sometimes disallowing Empericus his Division affirms that the species of motion made by an External principle are Traction Pulsion Vection and Volutation upon good reason reducing Elation and Depression to either Traction or Pulsion forasmuch as a body may be elevated or depressed by either â—raction or Pulsion But yet He hath left us rather a Confusion than logical Discrimination of the species of Violent motion for Collision and Pulsion are one and the same thing and Vection may be performed either by Pulsion or Traction insomuch as the thing movent doth not forsake the thing pulsed or drawn but constantly adhaereth unto it and as for Volutation it is both Pulsion and Traction at once as may be easily conceived by any man who seriously considers the manner thereof Nay Traction it self may be justly reduced to Pulsion forasmuch as the movent which is said to Draw a thing doth indeed nothing but Impel it by frequently reiterated small strokes either directly toward it self or to a lateral region and yet notwithstanding for plaâ—nness sake and the cleerer Demonstration of our praesent thesis we judge it convenient to conserve the Common Notion and to determine that all Motion impressed upon one body by another is performed in the General either when the movent Propels the moveable from it self or Attracts it toward it self For albeit the movent sometimes propels the thing moved from another body or attracts it to another yet can it not possibly do that but it must at the same time either Avert it in some measure from or Adduce it toward it self Nevertheless it is not to be denied but Pulsion is always the Chieâ— Species â—nd for that consideration alone is it that Proâ—ection which is only Impulâ—â—on or as Aristotle emphatically calls it a more Violent motion is generallâ— aâ—cepted as synonymous to Violent motion and that Philosophers seldoâ— or never Exemplifie Violent motion but in Projectills whether they be projected upward or downward â—â—anveâ—sly obliquely or any way whateveâ— These things considered◠〈◊〉 follows of pure necessity that the Downward motion of Heavy Boâ—â—es being caused not by any Inteâ—nal but bâ— an â—xternal Force impressed upon them must be effected either by Impulsion or by Traction Bâ— Impulsion it cannot because in the case of a stone throwneUpward ther◠〈◊〉 nothing External that can be imagined to impel 〈◊〉 Down again 〈…〉 attained the highest point of its mountee unless 〈◊〉 should be the 〈◊〉 and iâ— its Descent did proceed from the
impulâ—◠〈…〉 from below upon the upper part of the stone◠〈…〉 projection of the stone upward during its Ascent the motion thereoâ—â—ould in every degree of its remove from the proâ—â—cient be Accelerated 〈…〉 same proportion as it s Downward motion is Accelerated in everâ—â—â—gree of its descent but Experience testifies â—hat â—ts upward motion 〈…〉 and more Retarded in every degree of its remoâ—â— from the projiciâ—â—â— and therefore it cannot be that the Downward motion thereof should be â—â—used nay not so much as advanced by the Aer Which thing â—asâ—endus 〈◊〉 Epist. de proport qua Gravia decidentia aâ—celerantu◠〈…〉 â—â—monstrated and we our selves out of him 〈◊〉 the 9 Article of our 2 〈◊〉 concerning Gravity and Levity in the 3. Book praecedent Wha◠〈◊〉 can remain but that it must be by ATTRACTION 〈◊〉 because no other Attractive Force which might begin and continu◠〈◊〉 Downward motion of a stone can be imagined unless it be that Magâ—â—â—â—que Virtue of the Earth whereby it Draws all Terrene Bodies to an 〈…〉 it self in order to their and its own better Conservation 〈…〉 Conclude that the Cause of the Downwarâ— motion oâ— all 〈…〉 is the Magnetique Attraction of the Earth Nor need we adferr other â—â—guments in this place to confirm this Positionâ— in respect we have 〈◊〉 made it the chief subject of the 2 Sect. of our Chap. of Gravity 〈…〉 whether we therefore remit our unsatisfied Reader From the Cause of 〈◊〉 Downward motion of Heavy bodies let us advance to the Acceleration 〈◊〉 them in every degree of space through which 〈…〉 reason why we should at all enquire 〈…〉 upward moâ—ion of Light bodies in every degree 〈…〉 as we know of no man but Aristotle that 〈…〉 motion of Fire and Aer is slower in the beginning and gradually 〈◊〉 and swifter in the progress And so short was 〈…〉 proving that his sâ—â—gular conception by Experiment as he ought 〈…〉 assumed â—t upon 〈◊〉 credit of only one poor Argument which is 〈◊〉 〈…〉 and other things of the like light and aspiring 〈…〉 Caelo cap. 8. were Extruded and Impelled 〈…〉 descending and crouding toward the 〈…〉 force as some have contended and weâ—e 〈…〉 spontaneous tendency of their own inhaerent 〈…〉 moved more swiftly in the beginning and moâ—e slowly 〈…〉 their motion but Fire and Aer are more 〈…〉 beginning 〈…〉 more and more swift in the progress of their Assent therefore are they not moved upward by the Extrusion and Impulsion but spontaneously or by their own Levity And to Confirm his Minor proposition that Fire and Aer are Accelerated in every degree of their Assent without the suffrage of any Experiment He subjoyns only that as a Greater quantity of Earth is moved downward more swiftly than a less so is a Greater quantity of Fire moved upward more swiftly than a less which could not be if either of them were Impelled or moved by an External Force But this is as the Former meerly Petitionary for why should not a Greater quantity of Earth or Fire be moved more swiftly than a less both being moved as we suppose by External force in â—â—se the External force be proportionate to the quantity of each Doubtless the force of the ambient Aer extruding and impelling flame upward is alwayâ— so much the greater or more sensible by how much more Copious the â—â—re is as may be evinced even from the greater Impetus and waving motion of the flame of a great fire though it cannot yet be discerned whether that Undulous or waving motion in a Great flame be as He praesumeâ—â— more swift and rapid than that more calm and equal one observed in the flame of a Candle Thaâ— you l say is enough to detect the incircumspection of Aristotle in assuming upon so weak grounds that the motion of Light things Ascending is accelerated in the progress and that in the same proportion as that of Heavy things Descending is accelerated but not enough to refute the Position it self and therefore we think it expedient to superad a Demonstrative Reason or two toward the plenary Refutation thereof Seeing it is evident from Experience that a Bladder blown up is so much the more hardly depressed in deep water by how much neerer it comâ—s to the bottom and a natural Consequent thereupon that the bladder in respect of the Aer included therein beginning its upward motion at the bottom of the Water is moved toward the region of Aer so much the more slowâ—y by how much the higher it riseth toward the surface of the Water or lower part of the region of Aer incumbent thereupon and that the Cause thereof is thâ—s that so much the fewer parts of Water are incumbent upon the bladder and aer contained therein and consequently so much the less must that force of Extrusion be whereby the parts of Water bearing downward impel them upward we may well infer hereupon that if we imagine that any Flame should ascend through the region of Aer till it arrived at the region of Fire feigned to be immediately above the region of Aer that Flame would always be moved so much the slower by how much the higher it should ascend or by how much the neerer it should arive at the region of Fire Because Fire and Aer are conceived to be of the same aspiring nature and because the same Reason holds good in proportion for the decrease of Velocity in the ascension of Flame through the Aer as for that of the decrease of velocity in the ascension of Aer included in a bladder through Water And as for Aristotles other relatâ—ve Assertion that a Greater quantity of Earth is moved more swiftly Downward than a Less manifest 〈…〉 without nay 〈…〉 Eâ—perience doth 〈…〉 inhaerent in bodies accountâ—â— Heavy and that every body must therefore â—all down so much the morâ— swiftly and violently by how much the more of Gravity 〈◊〉 possesseth Hâ—ving thus totally subverted Aristotleâ— erroneous Tenent that the 〈◊〉 of Lâ—ght bodies Ascending is Acceleâ—aâ—â—d in every degree of their Aâ—â—â—ntion it follows that we apply our selves to the consideration of the 〈◊〉 of tâ—e motion of Heavy bodies 〈◊〉 in every degree 〈…〉 Descention Wheâ—ein the First obsâ—â—vâ—ablâ— oâ—â—urring iâ— the 〈…〉 or that it is so which is easily proved from hence that in all ages 〈…〉 been observed that the motion of 〈◊〉 things Descendent 〈…〉 the beginning and grows swifter and swiâ—â—â—◠〈◊〉 toward thâ— end 〈…〉 that in fine 〈◊〉 becomes highly rapid 〈…〉 that the 〈…〉 or impression made upon the Earth 〈…〉 down from 〈◊〉 high is always so much the greater or strongâ—â— by hâ—w much the 〈◊〉 â—he place is from which it â—ell The Second 〈◊〉 the 〈◊〉 or Cause of that velocity Encreasing in 〈…〉 which though enquired into by many of the Ancients seem◠〈…〉 been 〈◊〉 by none of them For 1 albeit Aristotle 〈◊〉 was so wary as 〈…〉 explicate his thoughts concerning it yâ—t â—oâ—h hiâ— great 〈◊〉 Simpliâ—â—â—â— tell
us â— in Comment 87. that it was Hâ—s opinion that a 〈…〉 other thing â—alling from on high is Corroboâ—â—ted 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 a Totalitate propria and hath its species maâ—â— morâ— and moâ—◠〈◊〉 as it comes neerer and neerer to its proper 〈◊〉 and so 〈…〉 degree of Gravity acceding to it in every â—egree of its 〈◊〉 to the Earth it is accordingly carried more and more swâ—ftly But 〈◊〉 that Simplicius hath not expounded how the 〈◊〉 stonâ— can 〈…〉 how it can be Corroborated or acquire more and more 〈…〉 its species or how that additament of fresh â—ravity should 〈…〉 judge you whether He hath done Aristotle 〈…〉 Author of that Opinion which instead of 〈◊〉 â—he 〈…〉 much more obscure than afore Besides we have the 〈…〉 that a descending body is not carried the more â—wâ—ftly by reâ—so◠〈◊〉 â—ny access or additament of Gravity a stone 〈…〉 ounce 〈…〉 as speedily down as one of an hundred pounâ— 2 Others 〈…〉 as the same Simplicius commemorates who 〈…〉 the Cause 〈…〉 the Decrease of the quantity of the Aer 〈◊〉 the sâ—oâ—◠〈◊〉 that by how much the higher a stone is by so 〈…〉 and so much the greater Resistence to the motion 〈…〉 much the greater quantity of the Aer resisting 〈…〉 consequently the resistence of the Aer growing 〈…〉 of the stones descent the velocity of its 〈…〉 proportion thereunto And this after 〈…〉 sinking in deep water more slowly 〈…〉 neer the bottom But though we admâ—t 〈…〉 stone Descending yet we 〈…〉 to mâ—ke â—ny sensible difference of 〈…〉 And would you have an Argument to 〈…〉 one fathom 〈…〉 fall the same 〈…〉 fathoms observe again with what velocity it passeth the last or tenth fâ—thom This done consider sinâ—e in the latter case the velocity shall be incompaâ—ably greater than in the former whether it be not necessary that thâ—t great auâ—mentation of velocity in the stone while it pervadeth the tâ—nth fathom of space must not arise from some other and more potent Câ—use thâ—n the resistence of the inferio◠〈◊〉 For in both caseâ— the stone carries the same proportion of weight and in the lowest fâ—thom there is the same quantity of Aer and consequently the same measure oâ— resistence And if you weigh the stone fiâ—st in some very high place â—nâ— afterward in a low or very neer the Earth surely you cannot expect to findâ—â—t heavier in the low place in respect of the lesser quantity of Aâ—r â—ubâ—jaâ—ent than in the high in respect of the greater quantity of Aer there 〈◊〉 it Lastly as for their Argument desumed from the slower sinkâ—ing of weights in deep than in shâ—llow 〈…〉 thereof 〈…〉 same with thâ—t of the more diffiâ—ult depression of a 〈…〉 Aer neer the bottom thâ—n neer the top of the 〈…〉 explained 3 A third â—onceipt there 〈◊〉 imputed to Hipparchuâ— by the 〈◊〉 Simplicius which comparing the Downward motion of a stone 〈◊〉 by its own proper Grâ—vity with the Upward motion of the 〈…〉 caused by an External â—orce impressed upon it by the 〈…〉 infers that as long as the force imprest praevails over the stones Gravity 〈◊〉 long is the stone carried upward and that more swiftly in the beginning because the â—orce is then strongest but afterward less and less swiftly because the same fâ—rce imprest is gradually debilitated until the stones proper Gravity at length getting the upper hand of the force imprest the stone begins it motion Downward which is slower in the beginning because the Gravity doth not yâ—t much praevail but afterwards grows more and more swâ—ft because the Gravity more and more praevails But this leaves us more than half way short of the Difficulty for though it be reasonable to assume that a certain Compensation of Velocity is made in both 〈…〉 that the Decrease of Velocity toward the end of the Upward motion is made up again by the Encrease of Velocity toward the end of the Downward and that in proportion to the degrees of space yet forasmuch as the motion of a stone falling down is constantly Accelerated not only after it hath been projected Upward but also when it is only dropt down from some high place to which perhaps it was never elevated but remained there from the beginning of the world as it often happens in deep mines the earth â—â—derneath the stones neer the surface of it being 〈…〉 cannot the stones Gravity gradually praevailing over the Imprest Force be as Hipparchus concludes the Cause of it◠〈…〉 of its Descent These Reasons thus deluding our Curiosity let us have 〈…〉 formerly asserted Position that All terrene 〈…〉 are Attracted by the magnetique Virtue of the Earth 〈…〉 that the magnetique Virtue of the Earth is 〈…〉 afar off and thereupon infer that the 〈…〉 therefore more rapid neer the earth than far from 〈…〉 took Virtue seems to be greater and so the 〈…〉 truth neerer the stone 〈…〉 and plausible to our first thought but insatisfactory to our second For if it were so then ought the Celerity of the stones motion in one fathom neer the Earth to be the same whether the stone be let fall from the altitude of only one fathom or from that of 10 20 an 100 fathoms when we exactly measure the spaâ—â— of time in which it pervades the one fathom neer the earth in the former case and compare it with that space of time in which it pervades the same lowest fathom in the latter It may be farther observed that whether a stone be let fall from a small or a great altitude the motion thereof for the first fathom of its descent is always of equal velocity i. e. it is not more nor less swift for the first fathom of its descent from the altitude of an 1â—â— fathoms than from the altitude of only two fathoms when yet it ought to be more swift for the first fathom of the two than for the first of the hundred if the Attraction of the Earth be more vehement neer at hand than far off in a sensible proportion We say in a sensible proportion because forasmuch as the magnetique rays emitted from it are diffused in â—ound from all parts of the superfice thereof and so must be so much the more dense and consequently more potent by how much less they are removed from it therefore must the Attraction be somewhat more potent at little than at very great distance but yet there is no tower or praecipice so high as to accommodate us with convenience to experiment whether the power of the Earths magnetique rayes is Greater to a sensible proportion in a very low place than in a very high And yet notwithstanding nothing seems more reasonable than to conceive that since the magnetique Attraction of the Earth is the true Cause of a stones Downward motion therefore it should be also the true Cause of the continual Increment of its Velocity during that motion But how it should be so there 's the Knot Which
this invented by Gassendus Thirdly we may account the Line DE for the first degree of Velocity acquired in the end of the first time insomuch as the first time AE is not individual but may be divided into so many instants or shorter times as there are points or particles in the line AE or AD so neither is the degree of Velocity individual or wholly acquired in one instant but from the beginning encreaseth through the whole first time and may be repraesented by so many Lines as may be drawn parallel to the Line DE betwixt the points of the Lines AD and AE so that as those Lines do continually encrease from the point A to the Line DE so likewise doth the Velocity continually encrease from the beginning of the motion and being represented what it is in the intercepted instants of the first time by the intercepted Lines it may be represented what it is in the last instant of the same first time by the Line DE drawn betwixt the two last points of the Triangle ADE And because the Velocity thenceforward continuing its Encrease may be again signified by Greater and Greater Lines continently drawn betwixt all the succeeding points of the remaining Lines DB and EC hence comes it that the Line FG doth represent the degree of Velocity acquired in the end of the second moment the Line HI the Velocity acquired in the end of the third moment and the Line KL the velocity acquired in the end of the fourth moment And evident it is from hence how the velocities respond in proportions to the Times since by reason of the Triangles of a common angle and parallel bases it is well known that as DE are to EA so FG to GA HI to IA and KL to LA. Thus keeping your eye upon the Figure and your mind upon the Analogy you shall fully comprehend that in the first moment of Time the falling stone doth acquire one degree of Velocity and pervades one degree of space that in the second moment of Time it acquires another degree of Velocity which being conjoynd to the former makes two and in the mean while three spaces are pervaded that in the third moment it acquires another degree of Velocity which conjoyned to the two former makes three and in the mean while seven parts of space are pervaded and so forward You shall fully comprehend also that the Celerities obtain the same Ration as the moments of Time and that the spaces pervaded from the beginning to the end of the motion have the same Ration as the Quadrates of the moments of Time which we assumed to Demonstrate out of Gassendus But still it concerns you to remember that we here discourse of that Motion which is Equally or Uniformly Accelerated or whose velocity doth continually and uniformly encrease nor is there any moment of the consequent time in which the motion is not more swift than it was in every antecedent moment and in which it is not accelerated according to the same Reason For the want of this Advertisement in chief seems to have been the unhappy occasion of that great trouble the Learned Jesuit Petrus Cazraeus put Gassendus to in his two Epistles De Proportione qua Gravia decidentia accelerantur And this kindly conducts us to the Physical Reason of this Proportion in which the velocity of bodies Descending is observed to encrease For wholly excluding the supposition of the Aers assistance of the Downward motion of a stone by recurring above and so impelling it downward and admitting the Magnetick Attraction of the Earth to be the sole Cause of its Descent unto both which the considerations formerly alleadged seem to oblige us it is familiar for us to conceive that the Increment of its Celerity according to the proportion assigned ariseth from hence While in the first moment the earth attracts the stone one degree of Celerity is acquired and one degree of space is pervaded In the second moment the attraction of the Earth continuing another degree of celerity is acquired and three equal spaces are pervaded one by reason of the degree of celerity in the mean while acquired and two by reason of the degree of celerity formerly acquired and still persevering as that which is doubly â—equivalent to the new degree in the mean while acquired because it is Complete and entire from the very beginning of the 2d moment but the other is only acquiring or in fieri and so not complete till the end of the second moment Then according to the same Ration in the third moment another degree of celerity is acquired and five spaces equal are pervaded one by reason of the new degree of celerity in the mean while acquired and fower by reason of the two former persevering i. e. two in each moment praecedent or one of a duplicate aequivalency to the new one not yet complete Then in the fourth moment another degree of celerity is acquired and seven spaces are pervaded one by reason of the fresh degree in the interim acquired and six by reason of the three former perâ—â—vering i. e. two in each praecedent moment And so of the rest through the whole motion computing the degrees of encreasing Celerity by the ration of Quadrate Numbers Now many are the Physical Theorems and of considerable importance which might be genuinely deduced from this excellent and fruitful Physicomathematical speculation and as many the admired Apparences in nature that offer themselves to be solved by Reasons more than hinted in the same but such is the strictness of our method and weariness of our Pen that we can in the praesent make no farther advantage of it than only to infer from thence the most probable Reason of that so famous Phaenomenon The equal velocity of two stones or bullets the one of 100 pound the other of only one ounce weight descending from the same altitude experience constantly attesting that being dropt down together or turned off in the same instant from the top of a tower the Lesser shall arrive at the ground as soon as the Greater For this admirable Effect seems to have no other Cause but this that the Lesser body as it containeth fewer parts so doth it require the Impulses or strokes of fewer Magnetical rays by which the attraction is made and such is the proportion of the two forces as that each moveable being considered with what Resistence you please still is the force in the movent equally sufficient to overcome that resistence and a few magnetique rays suffice to the attraction of a few parts as well as many to the attraction of many parts So that the space being equal which both are to pervade it follows that it must be pervaded by both in equal or the same time Provided always that the two bodies assumed be of the same matter for in case they be of divers matters as the one of Wood the other of Iron or Lead that may cause some small
same motion begun in the hand is continued And therefore it seems also very unnecessary to require the impression of any new and distinct Force upon the stone projected by the projicient which should be the Cause of its motion after its Dismission seeing nothing else is impressed but the very motion to be continued through a certain space so that we are not to enquire what motive Virtue that is which makes the Persevering motion but what hath made the motion that is to persever In the moveable certainly there is none but a Passive Force to motion nor can the Active Force be required in any thing but the movent and should we with the Vulgar say that there is an Imprest Force remaining for some time in the thing moved or projected we could thereby understand no other than the Impetus or motion it self Here might we opportunely insist upon this that motion is impressed upon a thing moved only in respect that the thing moved hath less force of Resistence than the movent hath of Impulsion so that the movent forcing it self into the place of the moveable compels it to recede or give way and go into another place But it is more material for us to observe that when a thing projected is impelled it is first touched by the projicient only in those parts which are in its superfice or outside and that those outward parts being pressed by the impulse do drive inward or press upon the parts next to them and those again impel the parts next to them and those again the next to them till the impulse be by succession propagated quite through the body of the thing projected to the superficial parts in the opposite side and then begins the motion of the whole the parts reciprocally cohaering as hath been formerly explained in the example of a long pole or beam of wood Which being percussed but with a very gentle or softly stroke that one end hath all its parts so commoved successively as that the stroke may be plainly perceived by a man that lays his ear close to the other end which could not be if the impulse were not propagated from parts to parts successively through the whole substance of the beam To which it is requisite that we superad this observable also that by reason of the force made by Contact and that short Cohaesion of the moveable to the movent there is created a certain Tension or stress of all the parts of it towards the opposite region and of that by that means all the parts of the thing projected are disposed or conformed as it were into certain Fibers or direct Files of all which the most strong and powerful is that which being trajected through the Centre of Gravity in the thing projected becomes as it were the Axis to all the circumstant ones Our eys ascertain that unless the Centre of Gravity be in the middle of the thing projected or directly obverted to the mark at which the thing is thrown the thing instantly turns it self about and that part wherein the Centre of Gravity is always goes foremost and as it were carries the rest of the parts as that which is the most Direct and most Tense of all the Fibres And this cannot be effected but with some more or less Deflection from the mark at which the force according to the Centre and Axis of Gravity was directed forasmuch as the Centre of Gravity wherein many Fibres concur makes some Resistence and detorting the Fibres inflecteth them another way and so a new Axis is made pro tempore according to which the Direction of all the parts in their motion afterward is determined Hence is it that if you would hit a mark either with a sling or stone-bow you must choose a stone or bullet of an uniform matter and composition or at least turn the heavier part of the body to be thrown forward because otherwise it will Deflect more or less to one side or other according to the position and inclination of its Centre of Gravity Moreover whether soever the thing projected doth tend all the Fibers constantly follow the Direction of the Axis or are made parallels thereunto so that as often as the Centre is changed so often doth the Axis so often do all the Fibres change their position and follow the Centre Which we insert chiefly in respect of the motion of Convolution or Turning of a thing projected immediately after its Dismission and of the Curvity of that Line which is thereby described whether ascending or descending But these are onely Transient Touches or Hints that we might easily intimate why a motion once imprest is continued rather this way than that and why Feathers Sponges and the like Light and Porous bodies are incapable of having quick and vehement motions imprest upon them because they consist of interrupted Fibres and such as are not Dirigible with the Centre of Gravity Here we ask leave once more to have recourse to that useful supposition of a stone situate in the immensity of the Imaginary spaces We lately said as you may remember that if a stone placed in the empty Extramundane spaces should be impelled any way the motion thereof would be continued the same way and that uniformly or equally and with tardity or celerity proportionate to the smartness or gentleness of the Impulse and perpetually in the same line because in those empty spaces it could meet with no cause which by Diversion might either accelerate or retard its motion Nor ought it to be Objected that nothing Violent can be Perpetual because in this case there could be no Repugnancy or Resistence but a pure indifferency in the stone to all regions there being no Centre in relation whereunto it may be conceived to be Heavy or Light And therefore the condition of the stone would be the very same as to Uniformity and Perpetuity of motion with that of the Caelestial Orbs which being obnoxious to no Retardation or Acceleration but free from all Repugnancy internal and Resistence External constantly and indeâ—inently maintain that Circular motion which was in the first moment of their Creation imprest uopon them by the Will of the Creator and that toward one part rather than any other Let us now farther consider seeing that if upon some large horizontal plane you should place a smooth Globe and then gently impel it you would observe it to be moved therupon equally and indefinently till it came to the end thereof why may you not lawfully conjecture that if the Terrestrial Globe were of a superfice exquisitely polite or smooth as the finest Venice Glass and another small Globe as polite were placed in any part of its superfice and but gently impelled any way it would be moved with constant Uniformity quite round the Earth according to the line of its first direction and having rowled once round the Earth it would without intermission again begin or rather continue another Circuit and so
Water of the same importaâ—ce Art 5. No Câ—mbuâ—tâ—â—le in Aer and so the opinion of the Ariâ—â—otâ—leans that the Extinctiâ—n of Flame imprisâ—ned is to be charged on the Defect of Aer for its sustentaâ—tiâ—n grosly erroneous Art 6. A fourth singular and memorable Experiment of the Authors of Yce at the nose of a large Reverberatory Furnace charged with Ignis rotae evidencing a Vacuity inter spersed in the Aer Art 7. An Inference from that Experiment that Aer as to its General Destination is the Common Receptaâ—y of Exhalations Art 8. A second â—llation that the Aer doth receive Exhalations at a certain rate or definite proportion which cannot be transcended without prodigious violence Art 9. The Existence of Inane Incontiguities in the Aer confirmed by two considerable Aâ—guments Art 1. That Water also contains Vacuola empty Spaces demonstrated Art 2. From the Experiment of the Dissolution of Alum Halinitre Sal Ammoniac and Sugar in Water formerly sated with the Tincture of Common Salt Art 3. The verity of the Lord 〈…〉 that a repeated 〈◊〉 not Rhuâ—barb 〈…〉 a virtue 〈…〉 a simpâ—e 〈…〉 in equal quantity and why Art 4. Why two Drachms of Antimony impragnaâ—e a pint of Wine with so strong a vomitory Faculty as two ounces Art 5. Why one and the same Menstruumâ—ay â—ay be enriched wiâ—h vâ—rious Tinctures Art 1. Two other Arguments of a Vacuity Dissâ—minate inferrible from 1 the difference of Bodies in the degrees of Gravity 2 the Calefaction of Bodies by the penetration of igneous Atoms into them Art 2. The Experiments vulgarly adduced to prove no vacuity in nature so far from denying that they confess a Disseminate one Art 3. The gâ—and Difficulty of the Câ—uâ—e of the Aers restitution of it self to iâ—s natural â—ontexture after raâ—efaction and condensation â—atisfied in brief Art 1. What is conceived by a Coacervate Vacuity and who was the Inventor of the famous Experiment of Quicksilver in a Glass Tube upon which many modern Physiologists have erected their perswasion of the possâ—bility of introducing it Experientiam apponam cusus invenâ—ionem etsi 〈◊〉 qui alii ambitiosiâ—s 〈…〉 tamen mihi conâ—â—at 〈◊〉 à Torricellio 〈…〉 Art 2. A 〈◊〉 description of the Expâ—riment and 〈◊〉 rate 〈◊〉 Art 3. The Authors reason for his selection of only six of the most considerable Phaenomenae to explore the Causes of them Art 1. The First Cardinal Difficulty Art 3. The Desert space in the Tube argued to be an absolute Vacuum coacervate from the impossibility of its repletion with Aer Art 5. The Vacuity in the Desert Space not praevented by the insinuation of Aether Art 6. A Paradâ—â— â—hat Nature doth not abhor all vacuity per se but only â—x Accidenti or in respect to Fluxility Art 7. A second Argument against the repletion of the Desert space by Aether Art 8. The Vacuity of the Desert space not praevented by an Halitus or Spiritual Efflux from the Mercury for three convincing reasons Art 9. The Authâ—rs Apostacy from the opinion of an absolute Coacervate Vacuity in the desert space in regard of Art 10. The possibiliâ— of the subingression of light Art 2. Of the Atoms or insensible bodies of Heat and Cold which are much more exile and penetrative then common Aer Art 12. Of the Magnetical Efflux of the Earth to which opinion the Author resigns his Assent Art 13. No absolute plenitude nor absolute Vacuiâ—y in the Desert Space but only a Disseminate Vacuity Art 1. The second Difficulty stated Art 2. Two things necessary to the creation of an excessive or praeternatural Vacuity Art 3. The occasion of Galilaeos invention of a Brass Cylindre charged with a wooden Embol or Sucker and of Torricellius invention of the praesent Experiment Art 4. The marrow of the Difficulty viz. How the Aer can be impelled upward by the Restagnant Quicksilver when there externally wants a fit space for it to circulate into Art 5. The solution of the same by the Laxity of the Contexture of the Aer Art 6. The same illustrated by the adaequate simile of Corne infused into a Busâ—el Art 7. A subordinate scruple why most bodies are moved through the Aer with so little resistence as is imperceptible by sense Art 8. The same Expeded Art 9. A second dependent scruple concerning the Cause of the sensible resistence of the Aer in this case of the Experiment together with the satisfaction thereof by the Gravity of Aer Art 1. The State of the Third Difficulty Art 2. The Solution thereof in a Word Art 3. Three praecedent positions briefly recognised in order to the worthy profounding of the mystery of tâ—e Aers resisting Compression beyond a certain rate or determinate proportion Art 4. The Aequiponderancy of the External Aer pendent upon the surface of the Restagnant Mercury in the vessel to the Cylindre of Mercury residuous in the Tube at the altitude of 27 digits the cause of the Mercuries constant subsistence at that point Art 5. A convenient 〈◊〉 illustrating and enforcing the same Art 6. The Remainder of the Difficulty viz. Why the Aequilibrium of these two opposite weights the Mercury and the Aer is constant to the praecise altitude of 27 dâ—gâ—tâ— remâ—ved Art 7. Humaâ—e Perspicacity terminated in the exterior parts of Nature or simple Apparitions which eluding our Cognition frequently fall under no other comprehension but that of rational Conjecture Art 8. The constant subsistence of the Mercury at 27 dâ—gits adscriptive rather to the Resistence of the Aer then to any occult Quality in the Mercury Art 9. The Analâ—gy betwixt the Absolute and Respective Aequality of weighâ—s of Quicksilver and Water in the different altitudes of 27 dâ—gits and 32 feet Art 10. The definite weights of the Mercury at 27 dâ—gits and Water at 32 feet in a Tube of the third part of a digit in diametre â—â—und to be near upon two pouâ—d Paris weiâ—ht * Consulâ—ndus Mersennus in tract de Mensuris ponderibus cap 1. 〈◊〉 physicomathemat p. 229. Art 11. Quaere Why the Aequilibrium is constant to the same point of altitude in a Tube of a large concave as well as in one of a small when the force of the Depriment must be greater in the one then the other Art 12. The solution thereof by the appropriation of the same Cause which makes the descent of two bâ—dies of different weights aequivelox Art 1. The Fourth Capital Difficulty proposed Art 2. The full solution thereof by demonstration Art 3. The same confirmed by the theory of the Cause of the Mercuries frequent Reciprocations before it acquiesce at the point of Aequipondium Art 1. The Fifth Principal Difficulty Art 2. Solved by the Motion of Restauration naâ—ural to each insensible particle of Aer Art 3. The incumbent Aer in this case equally distressed by two contrary Forces Art 4. The motion of Restauratiâ—n in the Aer extended to the satisfaction of another consimilar Doubt concerning the subintrusion
positions of its particles evidenced in the Example of a putrid Apple Art 11. The assenting suffrage of Epicurus Art 1. The Visible Images of objects substantial and either corporeal Emanations from the superficial parts of Concretions or Light it self disposed into contextures consimilar to the figure of the object Art 2. The position of their being 〈◊〉 derived from 〈◊〉 and pâ—â—ferred to the 〈…〉 Species Visible Art 3. Epicurus Text concerning the same Art 4. The faithful Exposition thereof Art 5. The Contents thereof reduced to 4 Heads Art 6. The Eâ—istenâ—e of Images visâ—ble certified by autoptical Demonstration Art 7. Epicurus opinion of the substâ—ntialâ—â—◠〈◊〉 Images Visiâ—le 〈…〉 Art 8. The 〈…〉 and Art 9. 〈…〉 Art 10. The grand 〈◊〉 of Alexander that a continual Efflux of substance must minorate the 〈◊〉 of the most solid 〈◊〉 Art 11. 〈…〉 Art 12. The 〈◊〉 oâ— Images 〈◊〉 reduced to some 〈…〉 Art 13. 〈…〉 Art 14. By Exempâ—â—fying in the numerous round Films of Wax successively derepâ—ed from a Wax 〈◊〉 by the flame thereof in the space of an hour and Art 15. In the innumerable Films of Oyl likewise successively delibrated by the flame of an Ellychnium or Match perpendicularly floating in a vessel of equal capacity with Solomons Braâ—en Sea in â—he space of 48 hours Art 16. By the Analogy betwixt an â—dorable Visible Species Art 7. The Manner and Reason of the Production of visible Images according to the hypothesis of Epicurus Art 18. The Celerity of the Motiâ—n of visible Images reasoned and compared to that of the Light of the Sun Art 19. The Translation of a moveable from place to place in an indivisible pâ—int of time impossible and why Art 20. The Facility of the Abduâ—tion or Aâ—olation of Images Visible from solid Concretions solved by the Spontaneous Eâ—silition of their superficial Atoms and the Sollicitation of Light incident upon them Art 21. That Objects do not emit tâ—â—ir Visible Images but when Illustrated a Conceit though paradoxicâ—l yet not improbable Art 1. Visible Images Systatical described and distinguisht from Apostatical ones Art 2. Their Existence assured by the testimony of Diodorus Siculus and Art 3. Damascius together with the Autopsy of Kircher Art 4. Kirchers Description of that famous Apparition at Rhegium called Morgana Rheginorum Art 5. Most ingenious Investigation of the Causes thereof Art 6. His admirable Artifice for the exhibition of the like aâ—real Representation in Imitation of Nature Art 1. The Reason of Vision according to the opinion of the Stoicks Art 2. Of Aristotle Art 3. O the Phythagoreans Art 4. Of Empedocles Art 5. Of Plato Art 6. O Epicurus Art 7. Of Mons. Des Cartes Art 8. The iâ—genuity of 〈◊〉 Conceit acknowledged but the solidity â—â—dubitated Art 9. The Opinion of Epicurus more satisfactory then any other because more Rational and less obnoxious to inexplicable Difficulties Art 10. The Two most considerable Difficulties opposed to Epicurus position of the Incursion of Substantial Images into the Eye Art 1. That the superfice of nobody is perfectly smooth evicted by solid Reasâ—n and Autâ—psie Art 2. That the visible Image doth consist of so many Rayes as there are Points designable in the whole superfice of the object and that each Ray hath its line of Tendency direct respective to the face of that particle in the superfice from which it is emitted Art 3. That the Density and Vnion of the Rayes composing the visible Image is greater or less according to their less or greater Elongation from the Object Art 4. That the Visible Image is neither total in the total medium nor total in every part thereof but so manifold as are the parts of the medium from which the objâ—ct is discernable Contrary to the Aristoteleans Art 5. PARADOX That no man can see the same particle of an object with both Eyes at once nay not with the same Eye if the level of its Visive Axe be changed Art 6. CONSECTARY That the Medium is not possessed with one simple Image but by an Aggregate of innumerable Images deradiate from the same object all which notwithstanding constitute but one entire Image Art 7. CONSECTARY 2. That Myriads of different Images emanant from different objects may be Coexistent in the Aer without reciprocal penetration of Dimensions or Confusiâ—n of particles contrary to the Peâ—ipateticks Art 8. That the place of the visible Images ultimate Reception and complete Perception is the Concave of the Retina Tunica Art 9. That the Faculty forms a judgmâ—nt of the Conditions of the Object according to the representation thereof by the Image at its impression on the principal part of Vision the Amphiblestrâ—ides Art 10. CONSECTARY That the Image is the Cause of Objects apparence of this or that determinate Magnitude Art 11. CONSECTARY 2. That no Image can repâ—enish the Câ—ncave of the Retina Tunica unless it be deradiated from an object of an almost Hemispherical ambite Art 12. Why when the Eye is open there is aâ—wayes pourtrayed in the bottom thereof some one Tâ—tal Image whose varioâ—â— Parts are the Specialâ—mages â—mages of the several things included in the visual Hemisphere Art 13. PARADOX That the prospect of a shilling or object of a small diametre is as great as the Prospect of the Firmament Art 14. Why an object appears both greater in Dimensions and more Distinct in parts near at hand than far off Art 15. Why an oâ—ject speculated through a Conveâ— Leâ—s appears both greater and more distinct but through a Concave â—eâ—s and more Confused than when speculated only with the Eye Art 16. DIGRESSION What Figur'd Perspicils are convenient for Old and what for Purblind persons Art 17. That to the Diâ—udication of one of two obâ—ects apparently Equal to be really the Greater is not required a greater Image but only an Opinion of its greater Distance Art 18. Des Cartes Opinion concerning the Reason of the Sights apprehending the Distance of an object Art 19. Unsatisfactory and that for two Considerations Art 20. And that more solid one of Gassendus viz. that the Cause of our apprehending the Distance â—f an object consisteth in the Câ—mparation â—f the 〈◊〉 things 〈◊〉 â—â—wixt the oâ—ject and the 〈◊〉 by the Ratiâ—nal Facuâ—â—â— embraced and corroboâ—â—ted Art 21. PARADOX That the same Object speculated by the same man at the same distance and in the same degree of light doth alwayes appear greater to one Eye than the other Art 22. A â—econd PARADOX That all men see distinctly but with â—ne Eye at once contrary to that eminent Optical Axiom that the Vâ—sive Axes of both eyes concurr and unite in thâ— oâ—jâ—ct Art 23. The three Degrees of Vision viz. most perfect perfect and imperfect and the verity of the Paradox restrained only to the two former Degrees Art 1. A research into the Reason of the different Effects of Convex and Concave Glasses as well Dioptrical as Catoptrical Art 2. A COROLLARIE Hinting the Causes why an Elliptical Concave
reflects the incident rayes in a more Acute angle than a Parabolical and a Parabolical than a Spherical Art 3. A CONSECTARY Why a Plane Perspicil exhibits an objâ—ct in genuine Dimenâ—ioâ—s but a Convex in Amplified and a Concave in minorated Art 1. A Recapitulation of the principal Arguments precedent and summary of the subsequent 10 The â—â—x Muscles viz. 1 The Dâ—â—ect as the Deprâ—ment 〈◊〉 Abducent 2 And Oblique as the 2 Circumactors or Lovers Muscles Art 3. Why the Situation of an object is perceived by the sight Art 5. The same illustrate by an Experiment Art 6. Why the Motiâ—n and Quiet of obâ—ects â—re dâ—scerned by the sight Art 7. Why 〈◊〉 Images imitaâ—e the motions of tâ—eâ—r Artiâ—pes oâ— Oâ—iginals Art 8. Wâ—y the rightâ—ide â—ide of a Câ—toptrical Image respects the Lâ—ft of its Exemplar And why two Catoptrick Glasses confrontingly posited cause a Râ—stitution of the parts of the Image to the natural Form Art 1. The Argument duely acknowledged to â—e superlatively Difficult iâ— not absolutely Aâ—ataleptâ—cal Art 2. The sentence of Aristâ—tle concerning the Nature of Colours and the Commentâ—â—y of Scalâ—geâ— thereupâ—n Art 3. The opinion of Plato Art 4. Of the Pythagorean and Stoiâ—k Art 5. Of the Spagyrical Philosophers Art 6. The reason of the 〈…〉 and election of Democritus and Epicurus judgâ—â—ent touching the Generaâ—iâ—n of Colâ—uâ—s Art 7. The Text of Epicurus fully and faithfully expounded Art 1. A PARADOX That there are no Colours in the Dark Art 2. A familiar Experiment attesting the Verity thereof Art 3. The Constancy of all Artificial Tinctures dependent on the constancy of Disposition in the superficial Particles of the Bodies that wear them Art 4. That sâ— generally magnifâ—ed Distinction of Colors into Inhâ—rent and meerly Apparent redargued of manifeâ—t Câ—ntradâ—ction Art 5. The Emphatâ—â—al or Evanâ—d Coloâ—rs created by 〈◊〉 nâ— less Râ—al 〈◊〉 than the â—ost 〈◊〉 Tiâ—ctures Art 6. COROLLARY The Reasons of Emphatical Colours appinged on Bodies objected by a Prism Art 7. The true Difference of Emphatical and Durable Colour◠〈◊〉 Art 8. No Colour Formally inâ—â—erent in objects but onl◠〈◊〉 or 〈◊〉 câ—â—â—rary to the constant 〈…〉 Art 9. 〈…〉 â—arther â—indiâ—ated from Difficulty by the 〈…〉 praâ—cedeâ—◠〈…〉 oâ— the Aâ—â—mists Art 1. The Nativity of White or the reason of its percepâ—ion by the sight Art 2. Black a meet Privation of Light Art 3. The Genealogâ— of all Intermediate Color Art 4. The Causes of the Sympathy Antipathy of some Colours Art 5. The intermistion of small shadows among the lines of Light absolutely necessary to the Generation of any Intermediate Colour Art 6. Two eminent PROBLEMS concerning the Generation and Transposition of the Vermillion and Caeâ—ule appinged on Bodies by Prismes Art 7. The Solution of the Former with a rational Conjecture of the Cause of the Blew apparent in the Concave of the Heavens Art 8. The Solution of the Later Art 9. The Reasons why the Author proceeds not to investigate the Causes of Compound Colours in Particular Art 10. He confesseth the Erection of this whole Discourse on simple Conjecture and enumerates the Difficulties to be subdued by him who hopes to attain an Apodictical Knowledge of the Essence Causes of Colours Art 11. Des Cartes attempt to dissolve the chief of those Difficulties unsucsessful because grounded on an unstable Hypothesis Art 1. The Clasp or Ligament of this to the praecedent Chapter Art 2. The Authors Notion of the Rays of Light Art 3. A Parallelism betwixt a stream of Watâ—r exsilient from the Cock of a Cistern and a Ray of Light emanant from its Lucid Fountain PRAECONSIDERABLES Art 4. Light distinguisht into Primary Secondary c. Art 5. All Light Debilitated by Reflection and why Art 6. An Example sensibly demonstrating the same Art 7. That light is in perpetual Motion according to Arist. Art 8. Light why Corroborated in some cases and Debilitated in others by Refraction COROLLARY Why the Figure of the Sun both rising setting apâ—ears rather Elliptical than Sphaerical Art 9. PARADOX That the proportion of Solary Rayes reflected by the superiour Aer or Aether toward the Earth is so smaâ—l as not to be sensible Art 10. That every Lucid Body as Lucid doth emit its Rayes Sphâ—erically but as Visible Pyramidally Art 11. That Light is invisible in the pure medium Art 1. The Necessity of the Authors confirmation of the Fâ—â—st Praeconsiderable Art 2. The CORPORIETY of Light demonstrated by its jâ—st Attributes viz. 1 Locomotion 2 Resilition 3 Refraction 4 Coition 5 Disgrâ—gation 6 Igniety Art 3. Aristotles Definition of Lighâ— a meer Ambage and incomprehensible Art 4. The 〈◊〉 of Light impâ—rts not the Coexistence of two Bâ—dies in one Place contrary to the Peripatetick Art 5. Nor the motion of a Bâ—dy to be Instantaneâ—us Art 6. The Invisibilitâ— of â—ight in the limpid medium no Argument of its Immateriality as the Peripatetick praesumes Art 7. Tâ—e Corporiety of Light fully consistent with the Duration of the Sun contrary to the Peripatetick Art 8. The inâ—â—nsibility of Heat in many Lucent Bâ—dieâ— no valid Argument against the praesent Thesis that Light is Flame Attenuated Art 1. An Elogy of the sense of Hearing and the Relation of this and the praecedent Chapter Art 2. The great Affinity betwixt Viâ—ibleâ—nd â—nd Audible species in their representation of the superficial Conditions of Objects Art 3. In the Causes and manner of their Destruction Art 4. In their Actinâ—bolism or Diffusion both Sphaerical and Pyramidal Art 5. In their certifying the sense of the Magnitude Figure and otherâ— Qualities of their Originals Art 6. In the obscuration of Less by Greater Art 7. In their offâ—nce of the organs when excessive Art 8. In thâ—ir production of Heat by Multiplication Art 9. In their Variability according to the various disposition of the Medium Art 10. In their chief Attributes of Lâ—comotion Exsilitiâ—â— â—mpaction Resilition Dâ—â—gregation Congâ—egation Art 1. The Product of the Praemises concerning the points of Consent Dissent of Audible and Visible Species viz. That Sounds are Corporeal Art 2. An obstruction oâ— praejudice from the generally supposed repugnant Authâ—rities of some of the Ancients expeded Art 3. An Argument of the Corporiety of Sounds Art 4. A Second Argumenâ— Câ—ROLLARâ— Art 5. The 〈…〉 where 〈…〉 dâ—sâ—ant fâ—â—m â—he Sonant aâ—d Repâ—â—cuâ—iâ—â—â— COROLLARY 2. Art 6. Why Concaves yeild the strongest and longest Sounds COROLLARY 3. Art 7. The reason of Conâ—urrent Echoes where the Audient is near the Reflectent and remote from the sonant COROLLARY 4. Art 8. Why Echoes Monâ—phâ—n rehearâ—e so much the fewer syllables by how much nearer the audient is to the Reflectenâ— COROLLARY 5. Art 9. The reaâ—on of Pâ—lyphâ—n Echoes Art 10. A Third Argument of the Materiality of Sâ—unds Art 11. The necessity of a certain Configuration in a Sound inferred from the Distinction of one sound from another by the Sense Art 12. The same confirmed by the Aâ—ctority
to Aristotle Art 1. The Link connecting this Section to the former Art 2. That Cold is no Privation of Heat but a Real and Positive Quality demonstrated Art 3. That the adaequate Notion of Cold ought to be deâ—umed from its General Effect viz. the Congregation and Compaction of bodies Art 4. Cold no â—mmaterial but a Substantial Quality Art 5. Gassendus conjectural Assignation of a Tetrahedical Figure to the Atoms of cold asserted by sundry weighty considerations Art 6. Cold not Essential to Earth Water nor Aer Art 7. 〈…〉 Art 8. Water the chief Antagonist to Fire not in respect of its Accidental Frigidity but Essential Humidity and that the Aer hath a juster title to the Principality of Cold than either Water or Earth Art 9. â—ROBLEM Why the breath of a man doth Warme when expiâ—ed with the mâ—uth wide open Cool when efflated with the mouth contracted Art 10. 〈…〉 the premises Art 1. Why Fluidity and 〈◊〉 are here considered before Humidity and 〈◊〉 Art 2. 〈…〉 Art 3. 〈…〉 a Firme Art 4. Fluidity defined Art 5. Wherein the Fâ—rmal Reaâ—on thereof doth consisâ— Art 6. The â—ame â—arther illustrated by the twoâ—â—â—ld Fluidâ—ty of Metals and tâ—e peculiar reason of each Art 7. Firmness defined Art 8. And dâ—rived froâ— either of â— Causes Art 1. Humidity defined Art 2. 〈◊〉 defined Art 3. 〈…〉 Art 5. PROBLEM 1. Why pure water cannot wash out oyle from a Cloâ—â— which yet waâ—er wherein Ashes have been decoâ—ted or soap dissolved easily doth Solut. Art 6. PROBLEM 2 Why stains of Ink are not to be taken out of cloths but with â—ome Acta Liquor Solut. Art 1. The 〈◊〉 of the Chapâ—er Art 2. 〈◊〉 â—nd Soft 〈◊〉 Art 3. The Difference betwixt a Sâ—ft and Fluid Art 4. Solidity of Atoms the Fundament of Hardness and Inanity intercepted amâ—ng them the fuâ—dament of Softness in all Concretions Art 5. Hardneâ—s and Soâ—â—nesâ— no 〈◊〉 but mâ—â—rly â—omparative Qualities as adscriptive to Concretions contrary to Aristotle Art 6. Sâ—ftness in Firme things deduced from the same cause as Fluidity in Fluid oneâ— Art 7. The General Reason of the Mollification of Hard and Indâ—ration of Sofâ— bodies Art 8. The special manners of the Mollification of Hard and Induration of Soft bodies Art 9. PRâ—â—LEM Why Iron is Hardned by being immersed red-hot into Cold Water and its SOLUTION Art 10. The Formal Reasons of Softness and Hardness Art 11. The ground of Aristotles Distinction betwixt Formatilia and Preâ—â—ilia Art 12. Two Axioms concerning illustrating the nature of Softness Art 1. Flexilitâ— â—â—actility â—uctility c. deâ—ived from Sâ—â—iness and Rigidity from â—aâ—dnâ—â—s Art 2. PROBLEM What is the Câ—use of the motion of Restoration in Flexiles and the SOLUT. Art 3. Two Obstructions expeded Art 4. Why Flexile bodies grow weak by over-much and over frequent Bending Art 5. The Reason of the frequent Vibrations or Diadrâ—ms of Lutestrings other Tractile Bodies declared to be the same with that of the Restorative Motâ—â—n of Flexiles and Demonstrated Art 6. PROBLEM Why the Vibrations or Diadrâ—ms of a Chord distâ—â—ded and percussed are Aeâ—uitemporane â—us â—hough not Aeâ—â—ispatial and the SOLUT. Art 7. PROBLEM Why doth a Chord of a duple length perform its diadroms in a proportion of time duple to a Chord of a single length both being distended by equal force yet if the Chord of the duple length be distended by a duple fore or weight it doth not perform its Diadroms in a proportion of time duple to that of the other but only if the Force or weight distending it be quadruple to the First supposed and its SOLUT. Art 8. The Reasons of the vast Ductility or Extensibility of Gold Art 9. Sectility and Fissility the Consequents of Softness Art 10. Tractility and Friability the Consequents of Hardness Art 11. Ruptility the Consequent partly of Sâ—ftness partly of Hardness Art 12. PROBLEM Why Chords dâ—â—â—â—enced are more apt to break neer the Endâ— than in the middle â—nd its SOLUT. Art 1. That the Insensibility of Qualities doth not import their Vnintelligibility contrary to the presumption of the Aristotelean Art 2. Upon what grounds and by whâ—m the Sanctuary of Occult Qualities was erected Art 3. Occult Qualities and profest Ignorance all one Art 4. The Refuge of Sympathies and Antipathies equally obstructive to the advance of Natural Science with that of Ignoâ—e Proprieties Art 5. Thatall Attraction referred to Secret Sympathy and all Repulsion adscribed to secret Antipathy betwixt the Agent and Patient is effected by Corporeal Instruments and such as resemble those whereby one body Attracteth or Repelleth another in sensible and mechanique operations Art 6. The Means of Attractions sympathetical explicated by a convenient Simile Art 7. The Means of Abaction and Repulsions Antipathetical explicated likewise by sundry similitudes Art 8. The First and General Caâ—ses of all Love and Hatred betwixt Animals Art 9. Why things Alike in their natures love and delight in the Society each of other and why Vnlike natures abhor and avoid each other Art 1. Th◠〈◊〉 of Qualitâ—â— repuâ—ed â—ccult Art 2. Natures 〈…〉 in 〈◊〉 to the 〈◊〉 or Câ—â—â—piration of all parts of the Universe no Occult Qualâ—ty Art 3. The 〈…〉 of mans will Art 4. The Afflux and Reflux of the sâ—a inderivative from any immaterial Influx of the Moon Art 5. 〈…〉 of 〈…〉 and â—â—nversion of â—he 〈◊〉 and other Flowers Art 6. Why Garden Claver hideâ—h it sâ—alk in the heat of the day Art 7. Why the 〈…〉 usually 〈◊〉 soon after midnight and at break oâ— day Art 8. Why Shell-fish growe fat in the Full of the moon and lean again at the New Art 9. Why the Selenites resembles the Moon in all not several Aâ—spects Art 10. Why the 〈…〉 Art 11. 〈…〉 Art 12. A COROLLARY Why the Granules of Gold and Silver though much more pondrous then those of the Aqua Regis and Aqua Fortis wherein they are dissolved are yet held up and kept floating by them Art 13. The Cause of the Attraction of a Less Flame by a Greater Art 14. The Cause of the Invâ—â—ation of flame to Naphtha at distance Art 15. Of the Ascention of Water into the pores of a Spunge Art 16. The same illâ—strated by the example of a Syphon Art 17. The reason of the Percolation of Liquors by a cloth whose one end lieth in the liquor and other hangs over the brim of the vessel that contains it Art 18. The reasâ—â— of the 〈…〉 that ar◠〈◊〉 Art 19. The reason of the Discent betwixt Lute-strings of sheeps Guts and those of Woolfs Art 20. The tradition of the Consuming of all Feathers of Foul by those of the Eagle exploded Art 21. Why some certain Plants befriend and advance the growth and fruitfulness of others that are their neighbours Art 22. Why sâ—me Plants thrive 〈…〉 of some others Art 23. The â—â—ason of the great Frieâ—dship betwixâ— the Male and Femaâ—e Palm-trees Art 24. Why all â—â—ines grow â—ick and
Force thereupon and so promote the force imprest upon it by the hand of Him who projected it And must it not thence follow that the first imprest motion is so far from being decreased by the supposed Renitency of the superior Aer that it is rather increased and promoted by the Circulation thereof and upon consequence that the stone is carried upward twice as swiftly as it falls downward since it is impelled upward by two forces but falls down again only by a single force True it is that while a stone is falling down the distracted aer beneath seems to circulate into the place above deserted thereby but in case a stone be held up on high in the Aer by a mans hand or other support and that support be withdrawn so gently as to cause no considerable commotion in the Aer in this case there seems to be no reason why the Aer should flow from above down upon it in the first moment of its delapse Besides when a stone projected upward hath attained to the highest point of its ascent at which there seems to be a short pause or respite from motion caused by the aequilibration of the two Contrary Forces the Movent and Resistent why doth not the stone absolutely quiesce in that place there being in the Aer no Cause which should rather Depel it â—ownward then elevate it upward These considerations we ingenuously confess are potent and put us to the exigent of exploring some other External Principle beside the motion of Restitution in the Aer such as may Begin the Downward motion of the stone when gently dropt off from some convenient supporter or when it is at the zenith or highest point of its ascent and and at the term of its Aequilibration overcome the Resistence of the subjacent Aer that so it may not only yeeld to the stone in the first moment of its Descent but by successive Circulations afterward promote and gradually accelerate its motion once begun Depellent Cause there can be none and so there must be some Attrahent to begin the stones praecipitation and that can be no other but a Certain peculiar Virtue of the whole Terrestrial Globe whereby it doth not onely retain all its Parts while they are contiguous or united to it but also retract them to it self when by any violence they have been avulsed and separated And this Virtue may therefore be properly enough called Magnetique In Nature nothing is whole and entire in which there is not radically implanted a certain self-Conservatory Power whereby it may both contain its several parts in cohaerence to it self and in some measure resist the separation or distraction of them as all Philosophers upon the conviction of infinite Experiences decree and if so it were a very parâ—ial Aâ—sâ—rdity to bereave the Terraqueous Globe being a Body whole and entire of the like conservatory Faculty And hence comes it that if any Parts of the Earth be violently avelled from it by this Conservatory which must be Attractive Virtue it in some measure resisteth their avulsion and after the cessation of the Avelling violence retracteth them again and this by insensible Emanations or subtile threads deradiated continually from its whole body and hookt or fastned to them as a man retracts a Bird flown from his hand by a line or thread tyed to its feet By the Parts of the Terrestrial Globe we intend not only the parts of Earth and Water the liquid part of the Earth and as Blood in an Animal nor only all stones Metalls Minerals Plants Animals and whatever Bodies derive their principles from them such as Rain Dew Snow Hail and all Meteors Vapours and Exhalations nor only the Aer wherewith the globe of Earth is circumvested as a Quince or Malacotone is periwiggd about with a lanuginous or Hoary substance because if we abstract from the surface of the Earth all vapours expirations fumes and emanations of subtle bodies from water and other substances which ascend descend and everywhere float up and down in the Atmosphere nothing can remain about the same but an Empty space but also Fire it self which hath its original likewise from terrestrial matter as wood oyl fat sulphur and other unctuous and combustible substance Because all these are Bodies which as Parts of it self the Earth containeth and holds together not permitting any of them to be avelled from its orbe but by some force that exceeds its retentive power and when that avellent force ceaseth it suddainly retracts them again to it self And insomuch as two bodies cannot coexist in one and the same place at once therefore comes it to pass that many bodieâ— being at once retracted toward the Earth the more terrene are brought neerer to the surface thereof extruding and so succeeding in to the rooms of the less terrene whence the neerer adduced and Extruding Bodies are accounted Heavy and the Extruded and farther removed are accounted Light Secondly that the Earth is naturally endowed with a certain Magnetical Virtue by which perpetually diffused in round it containeth its parts in cohaerence and reduceth those which are separated from it self after the same manner as a Loadstone holds its own parts together and attracts Iron which is also a Magnetique Production as Gilbert de magnet lib. 1. cap. 16. from the observation of Miners and other solid reasons hath confirmed to it self and retracts it after divulsion or separation we say all this may be argued from hence that the whole Globe of the Earth seems to be nothing but one Grand Magnet 1 Because a Loadstone tornated into a sphere is more than Analogically only a Little Earth being therefore nicknamed by Gilbert de magnet lib. 1. cap. 3 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 Terella insomuch as the one so also hath the other its Poles its Axis Aequator Meridian Paralels 2 Excepting only some parts which have suffered an alteration and diminution if not a total amission of Virtue in the Exteriors of the Earth all parts thereof discover some magnetick impraegnation some more vigorous and manifest as the Loadstone and Iron others more languid and obscure as White Clay Bricks c. Whereupon Gilbert erects his conjectural judgement that the whole Globe Terrestrial is composed of two General parts the shell and Kernel the Shell not extending it self many hundred fathoms deep which is very small comparatively to the vastness of its Diametre amounting to 6872 miles Italian measure and all the rest or Kernel being one continued Loadstone substâ—ntially 3. The Loadstone always converteth those parts of it self toward the Poles which respected them in its mineral bed or while it remaind united to the Earth All which are no contemptible Arguments of our Thesis that the whole Earth is endowed with a magnetique Faculty in order to the Conservation of its Integrity Whether the Entrals of our Common Mother and Nurse the Earth be as Gilbert would persuade us one Great Loadstone substantially is not more impossible