shall forbear to exasperate and attempt to reconcile such persons to this Hypothesis as devout esteem for Holy Scripture and dutifull Respect to Canonical Injunctions hath made to stand off from this Opinion and therefore for their sakes I have at the end of the Dialogues by way of supplement added an Epistle of Galileo to Her Most Serene Highness Christina Lotharinga the Grand Dutchesse Mother of Tuscany as also certain Abstracts of John Kepler Mathematician to two Emperours and Didacus à Stunica a famous Divine of Salamanca with an Epistle of Paulo Antonio Foscarini a learned Carmelite of Naples that shew the Authority of Sacred Scripture in determining of Philosophical and Natural Controversies hoping that the ingenious impartial Reader will meet with full satisfaction in the same And least what I have spoken of the prohibiting of these Pieces by the Inquisition may deterre any scrupulous person from reading of them I have purposely inserted the Imprimatur by which that Office licenced them And for a larger account of the Book or Author I refer you to the Relation of his Life which shall bring up the Reare in the Second Tome What remains of this is that Excellent Discourse of D. Benedetto Castelli Abbate di San Benedetto Aloysio concerning the Mensuration of Running Waters with other Treatises of that Learned Prelate of the Superintendent Corsini Some may alledge and I doe confess that I promised to publish the Life of Galileo in this place But the great miscarriages of Letters from some Friends in Italy and else where to whom I am a Debtor for several Remarques from whom I daily expect yet greater Helps concerning the History of that famous Personage these disappointments I say joyned with the undeniable Request of some Friends who were impatient to see Castelli in English together with a consideration of the disproportionate Bulk that would otherwise have bin betwixt the two Volumes perswaded me to this exchange This deviation from my Promise I hope is Venial and for the expiating of it I plead Supererrogation having in each Tome made so large Aditions though to my great expense that they make neer a third part more than I stood by promise bound to Publish That this is so will appear by comparing the Contents I here prefix with the Advertisment I formerly Printed For not to mention those Epitomes of Kepler and à Stunica the whole second and following Books of Castelli were not come to my hands at the time of my penning that Paper yet knowing how imperfect the Volume would be without them they being partly a supplement to the Theoremes and Problemes which the Abbot had formerly Printed and partly experiments that had procured him and his Doctrine a very great Reputation knowing this I say I apprehended a necessity of publishing them with the rest and hope that if you think not the service I have done therein worth your acknowledgement you will yet at least account the encrease of my expence a sufficient extenuation of the Trespass that those Additions have forced me to commit upon your Patience in point of Time As for the second Tome I have only this to assure the Generous Readers 1 that I am very confident I shall be much more punctual in publishing that than for the reasons above related I was able to be in setting forth this 2 that they shall not be abused in advancing of their moneys as hath bin used in the like case by selling the remaining Copyes at an under rate and 3 that I have a very great care that no disesteem may by my means arise unto this way of publishing Books for that it is of excellent use in ushering Great and Costly Volumes into the World To say nothing of the disadvantages of Translations in general this of mine doubtless is not without it's Errours and oversights but those of the Printer discounted I hope the rest may be allowed me upon the score of Human Imbecilitie The truth is I have assumed the Liberty to note the Mistakes in the Florid Version of Berneggerus in the Margent not so much to reproach him as to convince those who told me that they accounted my pains needless having his Latine Translation by them The like they said of the whole two Tomes but they thereby caused me to question their Understanding or Veracity For some of the Books were yet never extant As for instance the Mechanicks of Monsieur Des Cartes a Manuscript which I found amongst the many other Rarities that enrich the well-chosen Library of my Learned and Worthy Friend Dr. Charles Scarburgh the Experiments of Gravity and the Life of Galileo both my own Others were included in Volumes of great price or so dispersed that they were not to be purchased for any money as those of Kepler à Stunica Archimedes Tartaglia and the Mechanicks of Galileo And the remainder though easyer to procure were harder to be understood as Tartaglia his notes on Archimedes Torricellio his Doctrine of Projects Galileo his Epistle to the Dutchesse of Tuscany and above all his Dialogues de Motu never till now done into any Language which were so intermixt of Latine and Italian that the difficulty of the Stile joyned with the intricatnesse of the Subject rendered them Unpleasant if not wholly Vnintelligible to such as were not absolute Masters of both the Tongues To conclude according to the entertainment that you please to afford these Collections I shall be encouraged to proceed with the Publication of a large Body of Hydrography declaring the History Art Lawes and Apendages of that Princely Study of Navigation wherein I have omitted nothing of note that can be found either in Dudley Fournier Aurigarius Nonius Snellus Marsennus Baysius Morisetus Blondus Wagoner abroad or learnt amongst our Mariners at home touching the Office of an Admiral Commander Pilot Modellist Shipwright Gunner c. But order requiring that I should discharge my first Obligation before I contract a second I shall detein you no longer in the Portall but put you into possession of the Premises Novemb. 20. 1661. T. S. THE AUTHOR'S INTRODUCTION Judicious Reader THere was published some years since in Rome a salutiferous Edict that for the obviating of the dangerous Scandals of the present Age imposed a seasonable Silence upon the Pythagorean Opinion of the Mobility of the Earth There want not such as unadvisedly affirm that that Decree was not the production of a sober Scrutiny but of an illinformed Passion one may hear some mutter that Consultors altogether ignorant of Astronomical Observations ought not to clipp the Wings of Speculative Wits with rash Prohibitions My zeale cannot keep silence when I hear these inconsiderate complaints I thought fit as being thoroughly acquainted with that prudent Determination to appear openly upon the Theatre of the World as a Witness of the naked Truth I was at that time in Rome and had not only the audiences but applauds of the most Eminent Prelates of
MATHEMATICAL Collections and Translations In two TOMES THE SYSTEME OF THE WORLD IN FOUR DIALOGUES Wherein the Two GRAND SYSTEMES OF PTOLOMY and COPERNICUS are largely discoursed of And the REASONS both Phylosophical and Physical as well on the one side as the other impartially and indefinitely propounded By GALILEUS GALILEUS LINCEUS A Gentleman of FLORENCE Extraordinary Professor of the Mathematicks in the UNIVERSITY of PISA and Chief Mathematician to the GRAND DUKE of TVSCANY Englished from the Original Italian Copy by THOMAS SALUSBURY ALCINOUS 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 SENECA Inter nullos magis quam inter PHILOSOPHOS esse debet aequa LIBERTAS LONDON Printed by WILLIAM LEYBOURNE MDCLXI To the most Serene Grand DUKE OF TUSCANY THough the difference between Men and other living Creatures be very great yet happly he that should say that he could shew little less between Man and Man would not speak more than he might prove What proportion doth one bear to a thousand and yet it is a common Proverb One Man is worth a thousand when as a thousand are not worth one This difference hath dependence upon the different abilities of their Intellectuals which I reduce to the being or not being a Philosopher in regard that Philosophy as being the proper food of such as live by it distinguisheth a Man from the common Essence of the Vulgar in a more or less honourable degree according to the variety of that diet In this sence he that hath the highest looks is of highest quality and the turning over of the great Volume of Nature which is the proper Object of Philosophy is the way to make one look high in which Book although whatsoever we read as being the Work of Almighty God is therefore most proportionate yet notwithstanding that is more absolute and noble wherein we more plainly deserne his art and skill The Constitution of the Vnivers among all Physical points that fall within Humane Comprehension may in my opinion be preferred to the Precedency for if that in regard of universal extent it excell all others it ought as the Rule and Standard of the rest to goe before them in Nobility Now if ever any persons might challenge to be signally distinguished for Intellectuals from other men Ptolomey and Copernicus were they that have had the honour to see farthest into and discourse most profoundly of the World 's Systeme About the Works of which famous Men these Dialous being chiefly conversant I conceived it my duty to Dedicate them only to Your Highness For laying all the weight upon these two whom I hold to be the Ablest Wits that have left us their Works upon these Subjects to avoid a Solecisme in Manners I was obliged to address them to Him who with me is the Greatest of all Men from whom they can receive either Glory or Patrociny And if these two persons have so farre illuminated my Understanding as that this my Book may in a great part be confessed to belong to them well may it also be acknowledged to belong to Your Highness unto whose Bounteous Magnificence I owe the time and leasure I had to write it as also unto Your Powerful Assistance never weary of honouring me the means that at length I have had to publish it May Your Highness therefore be pleased to accept of it according to Your accustomed Goodness and if any thing shall be found therein that may be subservient towards the information or satisfaction of those that are Lovers of Truth let them acknowledge it to be due to Your Self who are so expert in doing good that Your Happy Dominion cannot shew the man that is concerned in any of those general Calamities that disturb the World so that Praying for Your Prosperity and continuance in this Your Pious and Laudable Custome I humbly kiss Your Hands Your Most Serene Highnesses Most Humble and most devoted Servant and Subject GALILEO GALILEI To the Noble and most perfectly Accomplished Sr. JOHN DENHAM Knight of the Noble Order of the BATH And Surveyor General of his Maties Works c. SIR I Humbly begge your Pardon for bringing this Book under your Protection Were it a VVork of my own or I any thing but the Translatour I should master my Thoughts to a meaner Dedication But being a Collection of some of the greatest Masters in the VVorld and never made English till now I conceived I might sooner procure their VVelcome to a person so eminent for Noble Candor as well as for all those Intellectual Excellencies wherewith Your Rich Soul is known to be furnished I resolv'd to be as kind to this Book as I could and seriously considering which way to effect it I at last concluded to prefix Your Name whom His Majesty and all his Subjects who have a higher Sense and Judgement of Excellent Parts know best able to defend my Imperfections And yet I confess there 's one thing makes against me which is your eminent Integrity and great Affection to Truth whereby my Lapses in a VVork of this Nature might justly despair of Shelter but that the Excellency of Your Native Candor strives for Predominancy over all Your great Abilities For 't is all-most impossible to think what Your Matchless VVit is not able to Conquer would Your known Modesty but give leave therefore Galileus Kepler and those other Worthies in Learning are now brought before You in English Habit having chang'd their Latine Italian and French whereby they were almost Strangers to our Nation unless to such as You who so perfectly master the Originals I know you have so much and great imployment for His Majesty and his good Subjects that I shall not robb you of another Minutes loss besides the liberty of subscribing my Self SIR Your Honours Most Humble and Most obedient Servant THOMAS SALUSBURY MATHEMATICAL COLLECTIONS AND TRANSLATIONS THE FIRST TOME IN TWO PARTS THE FIRST PART Containing I. GALILEUS GALILEUS His SYSTEM of the WORLD II. GALILEUS His EPISTLE to the GRAND DUTCHESSE MOTHER concerning the Authority of Holy SCRIPTURE in Philosophical Controversies III. JOHANNES KEPLERUS His Reconcilings of SCRIPTURE Texts c. IV. DIDACUS à STUNICA His Reconcilings of SCRIPTURE Texts c. V. P. A. FOSCARINUS His Epistle to Father FANTONUS reconciling the Authority of SCRIPTURE and Judgments of Divines alledged against this SYSTEM By THOMAS SALUSBURY Esq. LONDON Printed by WILLIAM LEYBOURN MDCLXI MATHEMATICAL COLLECTIONS AND TRANSLATIONS THE FIRST TOME THE FIRST PART Containing I. GALILEUS GALILEUS His SYSTEME of the World II. GALILEUS his EPISTLE to the GRAND DUTCHESSE Mother concerning the Authority of Sacred SCRIPTURE in Phylosophical Controversies III. JOHANNES KEPLERUS his Reconcilings of SCRIPTURE Texts c. IV. DIDACUS a STUNICA his Reconcilings of SCRIPTURE Texts c. V. P. A. FOSCARINUS his Epistle to Father FANTONUS reconciling the Authority of Sacred SCRIPTURE and Judgments of Divines alledged against c. By THOMAS SALUSBURY Esq. LONDON Printed by WILLIAM LEYBOURNE MDCLXI READER MAthematical Learning to speak nothing
by SIGNORE BARTOLOTTI in that affair of the DIVERSION of FIUME MORTO IX HIS CONSIDERATION upon the DRAINING of the PONTINE FENNS in CALABRIA X. HIS CONSIDERATION upon the DRAINING of the TERRITORIES of BOLOGNA FERRARA and ROMAGNA XI HIS LETTER to D. FERRANTE CESARINI applying his DOCTRINE to the MENSURATION of the LENGTH and DISTRIBUTION of the QUANTITY of the WATERS of RIVERS SPRINGS AQUEDUCTS c. XII D. CORSINUS SUPERINTENDENT of the GENERAL DRAINS and PRESIDENT of ROMAGNA his RELATION of the state of the VVATERS in the TERRITORIES of BOLOGNA and FERRARA A Table of the most observable Persons and Matters mentioned in the Second Part. The CONTENTS of the SECOND TOME PART THE FIRST Treatise I. GALILEUS GALILEUS his MATHEMATICAL DISCOURSES and DEMONSTRATIOMS touching two NEVV SCIENCES pertaining to the MECHANICKS and LOCAL MOTION with an APPENDIX of the CENTRE of GRAVITY of some SOLIDS in Four DIALOGUES II. HIS MECHANICKS a New PEICE III. RHENATUS DES CARTES his MECHANICKS translated from his FRENCH MANUSCRIPT a New PEICE IV. ARCHIMEDES his Tract DE INSIDENTIBUS HUMIDO with the NOTES and DEMONSTRASIONS of NICOLAUS TARTALEUS in Two BOOKS V. GALILEUS his DISCOURSE of the things that move in or upon the WATER VI. NICOLAUS TARTALEUS his INVENTIONS for DIVING UNDER WATER RAISING OF SHIPS SUNK c. in Two BOOKS PART THE SECOND I. EVANGELISTA TORRICELLIUS his DOCTRINE OF PROJECTS and TABLES of the RANGES of GREAT GUNNS of all sorts wherein he detects sundry ERRORS in GUNNERY An EPITOME II. T. S. his EXPERIMENTS of the COMPARATIVE GRAVITY OF BODIES in the AIRE and WATER III. GALILEUS GALILEUS his LIFE in Five BOOKS BOOK I. Containing Five Chapters Chap. 1. His Country 2. His Parents and Extraction 3. His time of Birth 4. His first Education 5. His Masters II. Containing Three Chapters Chap. 1. His judgment in several Learnings 2. His Opinions and Doctrine 3. His Auditors and Scholars III. Containing Four Chapters Chap. 1. His behaviour in Civil Affairs 2. His manner of Living 3. His morall Virtues 4. His misfortunes and troubles IV. Containing Four Chapters Chap. 1. His person described 2. His Will and Death 3. His Inventions 4. His Writings 5. His Dialogues of the Systeme in particular containing Nine Sections Section 1. Of Astronomy in General its Definition Praise Original 2. Of Astronomers a Chronological Catalogue of the most famous of them 3. Of the Doctrine of the Earths Mobility c. its Antiquity and Progresse from Pythagoras to the time of Copernicus 4. Of the Followers of Copernicus unto the time of Galileus 5. Of the severall Systemes amongst Astronomers 6. Of the Allegations against the Copern Systeme in 77 Arguments taken out of Ricciolo with Answers to them 7. Of the Allegations for the Copern Systeme in 50 Arguments 8. Of the Scriptures Authorities produced against and for the Earths mobility 9. The Conclusion of the whole Chapter V. Containing Four Chapters Chap. 1. His Patrons Friends and Emulators 2. Authors judgments of him 3. Authors that have writ for or against him 4. A Conclusion in certain Reflections upon his whole Life A Table of the whole Second TOME GALILAEUS Galilaeus Lyncaeus HIS SYSTEME OF THE WORLD The First Dialogue INTERLOCVTORS SALVIATUS SAGREDUS and SIMPLICIUS SALVIATUS IT was our yesterdayes resolution and agreement that we should to day discourse the most distinctly and particularly we could possible of the natural reasons and their efficacy that have been hitherto alledged on the one or other part by the maintainers of the Positions Aristotelian and Ptolomaique and by the followers of the Copernican Systeme And because Copernicus placing the Earth among the moveable Bodies of Heaven comes to constitute a Globe for the fame like to a Planet it would be good that we began our disputation with the examination of what and how great the energy of the Peripateticks arguments is when they demonstrate that this Hypothesis is impossible Since that it is necessary to introduce in Nature substances different betwixt themselves that is the Coelestial and Elementary that impassible and immortal this alterable and corruptible Which argument Aristotle handleth in his book De Coelo insinuating it first by some discourses dependent on certain general assumptions and afterwards confirming it with experiments and perticular demonstrations following the same method I will propound and freely speak my judgement submitting my self to your censure and particularly to Simplicius a Stout Champion and contender for the Aristotelian Doctrine And the first Step of the Peripatetick arguments is that where Aristotle proveth the integrity and perfection of the World telling us that it is not a simple line nor a bare superficies but a body adorned with Longitude Latitude and Profundity and because there are no more dimensions but these three The World having them hath all and having all is to be concluded perfect And again that by simple length that magnitude is constituted which is called a Line to which adding breadth there is framed the Superficies and yet further adding the altitude or profoundity there results the Body and after these three dimensions there is no passing farther so that in these three the integrity and to so speak totality is terminated which I might but with justice have required Aristotle to have proved to me by necessary consequences the rather in regard he was able to do it very plainly and speedily SIMPL. What say you to the excellent demonstrations in the 2. 3. and 4. Texts after the definition of Continual have you it not first there proved that there is no more but three dimensions for that those three are all things and that they are every where And is not this confirmed by the Doctrine and Authority of the Pythagorians who say that all things are determined by three beginning middle and end which is the number of All And where leave you that reason namely that as it were by the law of Nature this number is used in the sacrifices of the Gods And why being so dictated by nature do we atribute to those things that are three and not to lesse the title of all why of two is it said both and not all unless they be three And all this Doctrine you have in the second Text. Afterwards in the third Ad pleniorem scientiam we read that All the Whole and Perfect are formally one and the same and that therefore onely the Body amongst magnitudes is perfect because it is determined by three which is All and being divisible three manner of waies it is every way divisible but of the others some are dividible in one manner and some in two because according to the number affixed they have their division and continuity and thus one magnitude is continuate one way another two a third namely the Body every way Moreover in the fourth Text doth he not after some other Doctrines prove it by another demonstration Scilicet That no transition is made but
the first and more simple principles of Geometry yea I admire that Simplicius in admitting the supposition which he speaketh of doth not see the monstrous absurdity that is couched in it SIMP It s possible that I may have erred in relating it but that I see any fallacy in it I am sure is not true SALV Perhaps I did not rightly apprehend that which you said Do you not say that this Authour maketh the velocity of the bullet in descending equall to that which it had in turning round being in the concave of the Moon and that comming down with the same velocity it would reach to the centre in six dayes SIMP So as I think he writeth SALV And do not you peâ—ceive a shamefull errour therein But questionlesse you dissemble it For it cannot be but that you should know that the semidiameter of the Circle is lesse than the sixth part of the circumference and that consequently the time in which the moveable shall passe the semidiameter shall be lesse than the sixth part of the time in which being moved with the same velocity it would passe the circumference and that therefore the bullet descending with the velocity wherewith it moved in the concave will arrive in lesse than four hours at the centre supposing that in the concave one revolution should be consummate in twenty four hours as he must of necessity have supposed it for to keep it all the way in the same vertical line SIMP Now I thorowly perceive the mistake but yet I would not lay it upon him undeservedly for it 's possible that I may have erred in rehearsing his Argument and to avoid running into the same mistakes for the future I could wish I had his Book and if you had any body to send for it I would take it for a great favour SAGR. You shall not want a Lacquey that will runne for it with all speed and he shall do it presently without losing any time in the mean time Salviatus may please to oblige us with his computation SIMP If he go he shall finde it lie open upon my Desk together with that of the other Author who also argueth against Copernicus SAGR. We will make him bring that also for the more certainty and in the interim Salviatus shall make his calculation I have dispatch't away a messenger SALV Above all things it must be considered that the motion of descending grave bodies is not uniform but departing from rest they go continually accelerating An effect known and observed by all men unlesse it be by the forementioned modern Authour who not speaking of acceleration maketh it even and uniforme But this general notion is of no avail if it be not known according to what proportion this increase of velocity is made a conclusion that hath been until our times unknown to all Philosophers and was first found out demonstrated by the Academick our common friend who in some of his writings not yet published but in familiarity shewn to me and some others of his acquaintance he proveth how that the acceleration of the right motion of grave bodies is made according to the numbers uneven beginning ab unitate that is any number of equal times being assigned if in the first time the moveable departing from rest shall have passed such a certain space as for example an ell in the second time it shall have passed three ells in the third five in the fourth seven and so progressively according to the following odd numbers which in short is the same as if I should say that the spaces passed by the moveable departing from its rest are unto each other in proportion double to the proportion of the times in which those spaces are measured or we will say that the spaces passed are to each other as the squares of their times SAGR. This is truly admirable and do you say that there is a Mathematical demonstration for it SALV Yes purely Mathematical and not onely for this but for many other very admirable passions pertaining to natural motions and to projects also all invented and demonstrated by Our Friend and I have seen and considered them all to my very great content and admiration seeing a new compleat Doctrine to spring up touching a subject upon which have been written hundreds of Volumes and yet not so much as one of the infinite admirable conclusions that those his writings contain hath ever been observed or understood by any one before Our Friend made them out SAGR. You make me lose the desire I had to understand more in our disputes in hand onely that I may hear some of those demonstrations which you speak of therefore either give them me presently or at least promise me upon your word to appoint a particular conference concerning them at which Simplicius also may be present if he shall have a mind to hear the passions and accidents of the primary effect in Nature SIMP I shall undoubtedly be much pleased therewith though indeed as to what concerneth Natural Philosophy I do not think that it is necessary to descend unto minute particularities a general knowledg of the definition of motion and of the distinction of natural and violent even and accelerate and the like sufficing For if this were not sufficient I do not think that Aristotle would have omitted to have taught us what ever more was necessary SALV It may be so But let us not lose more time about this which I promise to spend half a day apart in for your satisfaction nay now I remember I did promise you once before to satisfie you herein Returning therefore to our begun calculation of the time wherein the grave cadent body would pass from the concave of the Moon to the centre of the earth that we may not proceed arbitrarily and at randon but with a Logical method we will first attempt to ascertain our selves by experiments often repeated in how long time a ball v. g. of Iron descendeth to the Earth from an altitude of an hundred yards SAGR. Let us therefore take a ball of such a determinate weight and let it be the same wherewith we intend to make the computation of the time of descent from the Moon SALV This is not material for that a ball of one of ten of an hundred of a thousand pounds will all measure the same hundred yards in the same time SIMP But this I cannot believe nor much less doth Aristotle think so who writeth that the velocities of descending grave bodies are in the same proportion to one another as their gravities SALV If you will admit this for true you must believe also that two balls of the same matter being let fall in the same moment one of an hundred pounds and another of one from an altitude of an hundred yards the great one arriveth at the ground before the other is descended but one yard onely Now bring your fancy if you can to
seemeth very reasonable that substances that under small bulk contain much matter should have narrower places assigned them leaving the more spacious to the more raâ—ified and there being dead of hunger and resolved into Earth would form a new little Globe with that little water which at that time was among the clouds It might be also that those matters as not beholding the light would not perceive the Earths departure but like blind things would descend according to their usual custom to the centre whither they would now go if that globe did not hinder them And lastly that I may give this Philosopher a less irresolute answer I do tell him that I know as much of what would follow upon the annihilation of the Terrestrial Globe as he would have done that was to have followed in and about the same before it was created And because I am certain he will say that he would never have been able to have known any of all those things which experience alone hath made him knowing in he ought not to deny me pardon and to excuse me if I know not that which he knows touching what would ensue upon the annihilation of the said Globe for that I want that experience which he hath Let us hear if he have any thing else to say SIMP There remains this figure which represents the Terrestrial Globe with a great cavity about its centre full of air and to shew that Graves move not downwards to unite with the Terrestrial Globe as Copernicus saith he constituteth this stone in the centre and demandeth it being left at liberty what it would do and he placeth another in the space of this great vacuum and asketh the same question Saying as to the first Lapis in centro constitutus aut ascendet ad terram in punctum aliquod aut non Si secundum falsum est partes ob solam sejunctionem à toto ad illud moveri Si primum omnis ratio experientia renititur neque gravia in suae gravitatis centro conquiescent Item si suspensus lapis liberatus decidat in centrum separabit se à toto contra Copernicum si pendeat refragatur omnis experientia cùm videamus integros fornices corruere Wherein he saith The stone placed in the centre either ascendeth to the Earth in some point or no. If the second it is false that the parts separated from the whole move unto it If the first it contradicteth all reason and experience nor doth the grave body rest in the centre of its gravity And if the stone being suspended in the air be let go do descend to the centre it will separate from its vvhole contrary to Copernicus if it do hang in the air it contradicteth all experience since we see whole Vaults to fall dovvn SALV I vvill ansvver though vvith great disadvantage to my self seeing I have to do vvith one vvho hath seen by experience vvhat these stones do in this great Cave a thing vvhich for my part I have not seen and vvill say that things grave have an existence before the common centre of gravity so that it is not one centre alone vvhich is no other than indivisible point and therefore of no efficacie that can attract unto it grave matters but that those matters conspiring naturally to unite form to themselves a common centre which is that about which parts of equal moment consist so that I hold that if the great aggregate of grave bodies vvere gathered all into any one place the small parts that vvere separated from their vvhole vvould follovv the same and if they vvere not hindered vvould penetrate vvherever they should find parts less grave than themselves but coming vvhere they should meet vvith matters more grave they vvould descend no farther And therefore I hold that in the Cave full of air the vvhole Vault vvould press and violently rest it self onely upon that air in case its hardness could not be overcome and broken by its gravity but loose stones I believe would descend to the centre and not swim above in the air nor may it be said that they move not to their whole though they move whither all the parts of the whole would transfer themselves if all impediments were removed SIMP That which remaineth is a certain Errour which he observeth in a Disciple of Copernicus who making the Earth to move with an annual motion and a diurnal in the same manner as the Cart-wheel moveth upon the circle of the Earth and in it self did constitute the Terrestrial Globe too great or the great Orb too little for that 365 revolutions of the Aequinoctial are less by far than the circumference of the great Orb. SALV Take notice that you mistake and tell us the direct contrary to what must needs be written in that Book for you should say that that same Copernican Author did constitute the Terrestrial Globe too little and the great Orb too big and not the Terrestrial Globe too big and the annual too little SIMP The mistake is not mine see here the words of the Book Non videt quòd vel circulum annuum aequo minorem vel orbem terreum justo multò fabricet majorem In English thus He seeth not that he either maketh the annual circle equal to the less or the Terrestrial Orb much too big SALV I cannot tell whether the first Author erred or no since the Author of this Tractate doth not name him but the error of this Book is certain and unpardonable whether that follower of Copernicus erred or not erred for that your Author passeth by so material an error without either detecting or correcting it But let him be forgiven this fault as an error rather of inadvertencie than of any thing else Farthermore were it not that I am already wearied and tired with talking and spending so much time with very little profit in these frivolous janglings and altercations I could shew that it is not impossible for a circle though no bigger than a Cart-wheel with making not 365 but lesse than 20 revolutions to describe and measure the circumference not onely of the grand Orb but of one a thousand times greater and this I sâ—y to shew that there do not want far greater subtilties than this wherewith your Author goeth about to detect the errour of Copernicus but I pray you let us breath a little that so we may proceed to the other Philosopher that opposeth of the same Copernicus SAGR. To confesse the truth I stand as much in need of respite as either of you though I have onely wearied my eares and were it not that I hope to hear more ingenious things from this other Author I question whether I should not go my ways to take the air in my Pleasure-boat SIMP I believe that you will hear things of greater moment for this is a most accomplished Philosopher and a great Mathematician and hath confuted Tycho in the businesse of the Comets and new
actuate it at the same instant with different and as it were of contrary motions I cannot believe that any one would say such a thing unlesse he had undertook to maintain this position right or wrong SALV Stay a little and find me out this place in the Book Fingamus modo cum Copernico terram aliqua suâ vi ab indito principio impelli ab Occasu ad Ortum in Eclipticae plano tum rursus revolvi ab indito etiam principio circa suimet centrum ab Ortu in Occasum tertio deflecti rursus suopte nutu à septentrione in Austrum vicissim I had thought Simplicius that you might have erred in reciting the words of the Author but now I see that he and that very grossely deceiveth himself and to my grief I find that he hath set himself to oppose a position which he hath not well understood for these are not the motions which Copernicus assignes to the Earth Where doth he find that Copernicus maketh the annual motion by the Ecliptick contrary to the motion about its own centre It must needs be that he never read his Book which in an hundred places and in the very first Chapters affirmeth those motions to be both towards the same parts that is from West to East But without others telling him ought he not of himself to comprehend that attributing to the Earth the motions that are taken one of them from the Sun and the other from the primum mobile they must of necessity both move one and the same way SIMP Take heed that you do not erre your self and Copernicus also The Diurnal motion of the primum mobile is it not from East to West And the annual motion of the Sun through the Ecliptick is it not on the contrary from West to East How then can you make these motions being conferred on the Earth of contraries to become consistents SAGR. Certainly Simplicius hath discovered to us the original cause of error of this Philosopher and in all probability he would have said the very same SALV Now if it be in our power let us at least recover Simplicius from this errour who seeing the Stars in their rising to appear above the Oriental Horizon will make it no difficult thing to understand that in case that motion should not belong to the Stars it would be necessary to confesse that the Horizon with a contrary motion would go down and that consequently the Earth would reoolve in it self a contrary way to that wherewith the Stars seem to move that is from West to East which is according to the order of the Signes of the Zodiack As in the next place to the other motion the Sun being fixed in the centre of the Zodiack and the Earth moveable about its circumference to make the Sun seem unto us to move about the said Zodiack according to the order of the Signes it is necessary that the Earth move according to the same order to the end that the Sun may seem to us to possesse alwayes that degree in the Zodiack that is opposite to the degree in which we find the Earth and thus the Earth running verbi gratia through Aries the Sun will appear to run thorow Libra and the Earth passing thorow the signe Taurus the Sun will passe thorow Scorpio and so the Earth going thorow Gemini the Sun seemeth to go thorow Sagittarius but this is moving both the same way that is according to the order of the signes as also was the revolution of the Earth about its own centre SIMP I understand you very well and know not what to alledge in excuse of so grosse an error SALV And yet Simplicius there is one yet worse then this and it is that he makes the Earth move by the diurnal motion about its own centre from East to West and perceives not that if this were so the motion of twenty four hours appropriated by him to the Universe would in our seeming proceed from West to East the quite contrary to that which we behold SIMP Oh strange Why I that have scarce seen the first elements of the Sphere would not I am confident have erred so horribly SALV Judg now what pains this Antagonist may be thought to have taken in the Books of Copernicus if he absolutely invert the sense of this grand and principal Hypothesis upon which is founded the whole summe of those things wherein Copernicus SAGR. I have twice or thrice observed in the discourses of this Authour that to prove that a thing is so or so he still alledgeth that in that manner it is conformable with our understanding or that otherwise we should never be able to conceive of it or that the Criterium of Philosophy would be overthrown As if that nature had first made mens brains and then disposed all things in conformity to the capacity of their intellects But I incline rather to think that Nature first made the things themselves as she best liked and afterwards framed the reason of men capable of conceiving though not without great pains some part of her secrets SALV I am of the same opinion But tell me Simplicius which are these different natures to which contrary to experience and reason Copernicus assignes the same motions and operations SIMP They are these The Water the Air which doubtlesse are Natures different from the Earth and all things that are in those elements comprised shall each of them have those three motions which Copernicus pretends to be in the Terrestriall Globe and my Authour proceedeth to demonstrate Geometrically that according to the Copernican Doctrine a cloud that is suspended in the Air and that hangeth a long time over our heads without changing place must of necessity have all those three motions that belong to the Terrestrial Globe The demonstration is this which you may read your self for I cannot repeat it without book SALV I shall not stand reading of it nay I think it an impertinency in him to have inserted it for I am certain that no Copernican will deny the same Therefore admitting him what he would demonstrate let us speak to the objection which in my judgment hath no great strength to conclude any thing contrary to the Copernican Hypothesis seeing that it derogates nothing from those motions and those operations whereby we come to the knowledge of the natures c. Answer me I pray you Simplicius Those accidents wherein some things exactly concur can they serve to inform us of the different natures of those things SIMP No Sir nay rather the contrary for from the idendity of operations and of accidents nothing can be inferred but an idendity of natures SALV So that the different natures of the Water Earth Air and other things conteined in these Elements is not by you argued from those operations wherein all these Elements and their affixes agree but from other operations is it so SIMP The very same SALV So
a minutes interval the same water to begin to return back again and the tide from ebbing to become young flood without standing still a moment an effect that as long as I have dwelt in Venice I never took notice of before SAGR. It is very much that you should be left thus on ground amongst small Channels in which rivolets as having very little declivity the rising or falling of the main sea the thickness onely of a paper is sufficient to make the water to ebbe and flow for good long spaces of time like as in some creeks of the Sea its flowing four or six yards onely maketh the water to overflow the adjacent Marshes for some hundreds and thousands of acres SIMP This I know very well but I should have thought that between the ultimate terme of ebbing and the first beginnng to flow there should have interposed some considerable interval of rest SAGR. This will appear unto you if you cast your eye upon the bank or piles where these mutations are made perpendicularly but not that there is any real time of cessation SIMP I did think that because these two motions were contrary there ought to be in the midst between them some kind of rest conformable to the Doctrine of Aristotle which demonstrates that in puncto regressus mediat quies SAGR. I very well remember this place but I bear in minde also that when I read Philosophy I was not thorowly satisfied with Aristotles demonstration but that I had many experiments on the contrary which I could still rehearse unto you but I am unwilling to sally out into any other digressions we being met here to discourse of the proposed mattes if it be possible without these excursions wherewith we have interrupted our disputes in those dayes that are past SIMP And yet we may with convenience if not-interrupt them at least prolong them very much for returning yesterday home I set my self to read the Tractate of Conclusions where I find Demonstrations against this annual motion ascribed to the Earth very solid and because I would not trust my memory with the punctual relation of them I have brought back the Book along with me SAGR. You have done very well but if we would re-assume our Disputations according to yesterdayes appointment it is requisite that we first hear what account Salviatus hath to give us of the Book De stellis novis and then without interruption we may proceed to the Annual motion Now what say you Salviatus touching those stars Are they really pull'd down from Heaven to these lower regions by vertue of that Authours calculations whom Simplicius mentioneth SALV I set my self last night to peruse his proceedings and I have this morning had another view of him to see whether that which he seemed over night to affirm were really his sense or my dreams and phantastical nocturnal imaginations and in the close found to my great grief that those things were really written and printed which for the reputation-sake of this Philosopher I was unwilling to believe It is in my judgment impossible but that he should perceive the vanity of his undertaking aswell because it is too apert as because I remember that I have heard him mentioned with applause by the Academick our Friend it seemeth to me also to be a thing very unlikely that in complacency to others he should be induced to set so low a value upon his reputation as to give consent to the publication of a work for which he could expect no other than the censure of the Learned SAGR. Yea but you know that those will be much fewer than one for an hundred compared to those that shall celebrate and extoll him above the greatest wits that are or ever have been in the world He is one that hath mentioned the Peripatetick inalterability of Heaven against a troop of Astronomers and that to their greater disgrace hath foiled them at their own weapons and what do you think four or five in a Countrey that discern his triflings can do against the innumerable multitude that not being able to discover or comprehend them suffer themselves to be taken with words and so much more applaud him by how much the lesse they understand him You may adde also that those few who understand scorn to give an answer to papers so trivial and unconcludent and that upon very good reasons because to the intelligent there is no need thereof and to those that do not understand it is but labour lost SALV The most deserved punishment of their demerits would certainly be silence if there were not other reasons for which it is haply no lesse than necessary to resent their timerity one of which is that we Italians thereby incur the censure of Illiterates and attract the laughter of Forreigners and especially to such who are separated from our Religion and I could shew you many of those of no small eminency who scoff at our Academick and the many Mathematicians that are in Italic for suffering the follies of such a Fabler against Astronomers to come into the light and to be openly maintained without contradiction but this also might be dispensed with in respect of the other greater occasions of laughter wherewith we may confront them depending on the dissimulation of the intelligent touching the follies of these opponents of the Doctrines that they well enough understand SAGR. I desire not a greater proof of those mens petulancy and the infelicity of a Copernican subject to be opposed by such as understand not so much as the very first positions upon which he undertakes the quarrel SALV You will be no lesse astonished at their method in confuting the Astronomers who affirm the new Stars to be superiour to the Orbs of the Planets and peradventure in the Firmament it self SAGR. But how could you in so short a time examine all this Book which is so great a Volume and must needs contain very many demonstrations SALV I have confined my self to these his first confutations in which with twelve demonstrations founded upon the observations of twelve Astronomers who all held that the Star Anno 1572. which appeared in Cassiopeia was in the Firmament he proveth it on the contrary to be beneath the Moon conferring two by two the meridian altitudes proceeding in the method that you shall understand by and by And because I think that in the examination of this his first progression I have discovered in this Authour a great unlikelihood of his ability to conclude any thing against the Astronomers in favour of the Peripatetick Philosophers and that their opinion is more and more concludently confirmed I could not apply my self with the like patience in examining his other methods but have given a very slight glance upon them and am certain that the defect that is in these first impugnations is likewise in the rest And as you shall see by experience very few words will suffice to confute this
whole Book though compiled with so great a number of laborious calculations as here you see Therefore observe my proceedings This Authour undertaketh as I say to wound his adversaries with their own weapons i. e. a great number of observations made by themselves to wit by twelve or thirteen Authours in number and upon part of them he makes his supputations and concludeth those stars to have been below the Moon Now because the proceeding by interrogatories very much pleaseth me in regard the Authour himself is not here let Simplicius answer me to the questions that I shall ask him as he thinks he himself would if he were present And presupposing that we speak of the foresaid Star of Anno 1572. appearing in Cassiopeia tell me Simplicius whether you believe that it might be in the same time placed in divers places that is amongst the Elements aud also amongst the planetary Orbs and also above these amongst the fixed Stars and yet again infinitely more high SIMP There is no doubt but that it ought to be confessed that it is but in one only place and at one sole and determinate distance from the Earth SALV Therefore if the observations made by the Astronomers were exact and the calculations made by this Author were not erroneous it were easie from all those and all these to recollect the same distances alwayes to an hair is not this true SIMP My reason hitherto tells me that so it must needs be nor do I believe that the Author would contradict it SALV But when of many and many computations that have been made there should not be so much as two onely that prove true what would you think of them SIMP I would think that they were all false either through the fault of the computist or through the defect of the observators and at the most that could be said I would say that but onely one of them and no more was true but as yet I know not which to choose SALV Would you then from false fundamentals deduce and establish a doubtful conclusion for true Certainly no. Now the calculations of this Author are such that no one of them agrees with another you may see then what credit is to be given to them SIMP Indeed if it be so this is a notable failing SAGR. But by the way I have a mind to help Simplicius and the Author by telling Salviatus that his arguments would hold good if the Author had undertook to go about to find out exactly the distance of the Star from the Earth which I do not think to be his intention but onely to demonstrate that from those observations he collected that the Star was sublunary So that if from those observations and from all the computations made thereon the height of the Star be alwayes collected to be lesse than that of the Moon it serves the Authors turn to convince all those Astronomers of most impardonable ignorance that through the defect either of Geometry or Arithmetick have not known how to draw true conclusions from their own observations themselves SALV It will be convenient therefore that I turn my self to you Sagredus who so cunningly aphold the Doctrine of this Author And to see whether I can make Simplicius though not very expert in calculations and demonstrations to apprehend the inconclusivenesse at least of the demonstrations of this Author first proposed to consideration and how both he and all the Astronomers with whom he contendeth do agree that the new Star had not any motion of its own and onely went round with the diurnal motion of the primum mobile but dissent about the placing of it the one party putting it in the Celestial Region that is above the Moon and haply above the fixed Stars and the other judging it to be neer to the Earth that is under the concave of the Lunar Orb. And because the situation of the new star of which we speak was towards the North and at no very great distance from the Pole so that to us Septentrionals it did never set it was an easie matter with Astronomical instruments to have taken its several meridian altitudes as well its smallest under the Pole as its greatest above the same from the comparing of which altitudes made in several places of the Earth situate at different distances from the North that is different from one another in relation to polar altitudes the stars distance might be inferred For if it was in the Firmament amongst the other fixed stars its meridian altitudes taken in divers elevations of the pole ought necessarily to differ from each other with the same variations that are found amongst those elevations themselves that is for example if the elevation of the star above the horizon was 30 degrees taken in the place where the polar altitude was v. gr 45 degrees the elevation of the same star ought to have been encreased 4 or 5 degrees in those more Northernly places where the pole was higher by the said 4 or 5 degrees But if the stars distance from the Earth was but very little in comparison of that of the Firmament its meridian altitudes ought approaching to the North to encrease considerably more than the polar altitudes and by that greater encrease that is by the excesse of the encrease of the stars elevation above the encrease of the polar elevation which is called the difference of Parallaxes is readily calculated with a cleer and sure method the stars distance from the centre of the Earth Now this Author taketh the observations made by thirteen Astronomers in sundry elevations of the pole and conferring a part of them at his pleasure he computeth by twelve collations the new stars height to have been alwayes beneath the Moon but this he adventures to do in hopes to find so grosse ignorance in all those into whose hands his book might come that to speak the truth it hath turn'd my stomack and I wait to see how those other Astronomers and particularly Kepler against whom this Author principally inveigheth can contein themselves in silence for he doth not use to hold his tongue on such occasions unlesse he did possibly think the enterprize too much below him Now to give you to understand the same I have upon this paper transcribed the conclusions that he inferreth from his twelve indagations the first of which is upon the two observations Of Maurolicus and Hainzelius from which the Star is collected to have been distant from the centre lesse than 3 semidiameters of the Earth the difference of Parallaxes being 4 gr 42 m. 30 sec. 3 semid 2. And is calculated on the observations of Hainzelius with Parall of 8. m. 30 sec. and its distance from the centre is computed to be more than 25 semid 3. And upon the observations of Tycho and Hainzelius with Parall of 10 m. and the distance of the centre is collected to be little lesse than 19 semid 4. And upon the observations of Tycho and the
he maketh no mention at all and much less of Mars than was needful I believe as being unable so well as he desired to salve a Phaenomenon so contrary to his Hypothesis and yet being convinced by so many other occurrences and reasons he maintained and held the same Hypothesis to be true Besides these things to make the Planets together with the Earth to move above the Sun as the Centre of their conversions and the Moon onely to break that order and to have a motion by it self about the earth and to make both her the Earth and the whole Elementary Sphere to move all together about the Sun in a year this seemeth to pervert the order of this Systeme which rendreth it unlikely and false These are those difficulties that make me wonder how Aristarchus and Copernicus who must needs have observed them not having been able for all that to salve them have yet notwithstanding by other admirable occurrences been induced to conside so much in that which reason dictated to them as that they have considently affirmed that the structure of the Universe could have no other figure than that which they designed to themselves There are also several other very serious and curious doubts not so easie to be resolved by the middle sort of wits but yet penetrated and declared by Coperninus which we shall defer till by and by after we have answered to other objections that seem to make against this opinion Now coming to the declarations and answers to those three before named grand Objections I say that the two first not onely contradict not the Copernican Systeme but greatly and absolutely favour it For both Mars and Venus seems unequal to themselves according to the proportions assigned and Venus under the Sun seemeth horned and goeth changing figures in it self exactly like the Moon SAGR. But how came this to be concealed from Copernicus and revealed to you SALV These things cannot be comprehended save onely by the sense of seeing the which by nature was not granted to man so perfect as that it was able to attain to the discovery of such differences nay even the very instrument of sight is an impediment to it self But since that it hath pleased God in our age to vouchsafe to humane ingenuity so admirable an invention of perfecting our sight by multiplying it four six ten twenty thirty and fourty times infinite objects that either by reason of their distance or for their extream smallnesse were invisible unto us have by help of the Telescope been rendered visible SAGR. But Venus and Mars are none of the objects invisible for their distance or smallnesse yea we do discern them with our bare natural sight why then do we not distinguish the differences of their magnitudes and figures SALV In this the impediment of our very eye it self hath a great share as but even now I hinted by which the resplendent and remote objects are not represented to us simple and pure but gives them us fringed with strange and adventitious rayes so long and dense that their naked body sheweth to us agrandized ten twenty an hundred yea a thousand times more than it would appear if the capillitious rayes were taken away SAGR. Now I remember that I have read something on this subject I know not whether in the Solar Letters or in the Saggiatore of our common Friend but it would be very good aswell for recalling it into my memory as for the information of Simplicius who it may be never saw those writings that you would declare unto us more distinctly how this businesse stands the knowledge whereof I think to be very necessary for the assisting of us to understand that of which we now speak SIMP I must confesse that all that which Salviatus hath spoken is new unto me for truth is I never have had the curiosity to read those Books nor have I hitherto given any great credit to the Telescope newly introduced rather treading in the steps of other Peripatetick Philosophers my companions I have thought those things to be fallacies and delusions of the Chrystals which others have so much admired for stupendious operations and therefore if I have hitherto been in an errour I shall be glad to be freed from it and allured by these novelties already heard from you I shall the more attentively hearken to the rest SALV The confidence that these men have in their own apprehensivenesse is no less unreasonable than the small esteem they have of the judgment of others yet it s much that should esteem themselves able to judge better of such an instrument without ever having made trial of it than those who have made and daily do make a thousand experiments of the same But I pray you let us leave this kind of pertinacious men whom we cannot so much as tax without doing them too great honour And returning to our purpose I say that resplendent objects whether it is that their light doth refract on the humidity that is upon the pupils or that it doth reflect on the edges of the eye-browes diffusing its reflex rayes upon the said pupils or whether it is for some other reason they do appear to our eye as if they were environ'd with new rayes and therefore much bigger than their bodies would represent themselves to us were they divested of those irradiations And this aggrandizement is made with a greater and greater proportion by how much those lucid objects are lesser and lesser in the same manner for all the world as if we should suppose that the augmentation of shining locks were v. g. four inches which addition being made about a circle that hath four inches diameter would increase its appearance to nine times its former bignesse but SIMP I believe you would have said three times for adding four inches to this side and four inches to that side of the diameter of a circle which is likewise four inches its quantity is thereby tripled and not made nine times bigger SALV A little more Geometry would do well Simplicius True it is that the diameter is tripled but the superficies which is that of which we speak increaseth nine times for you must know Simplicius that the superficies of circles are to one another as the squares of their diameters and a circle that hath four inches diameter is to another that hath twelve as the square of four to the square of twelve that is as 16. is to 144. and therefore it shall be increased nine times and not three this by way of advertisement to Simplicius And proceeding forwards if we should add the said irradiation of four inches to a circle that hath but two inches of diameter onely the diameter of the irradiation or Garland would be ten inches and the superficial content of the circle would be the area of the naked body as 100. to 4. for those are the squares of 10. and of 2. the agrandizement would
about its own centre in twenty four hours And that in the next place which is more exorbitant which happly for that reason you pass over in silence there is ascribed to it another revolution about its own centre contrary to the former of twenty four hours and which finisheth its period in a year In this my understanding apprehendeth a very great contradiction SALV As to the motion of descent it hath already been concluded not to belong to the Terrestrial Globe which did never move with any such motion nor never shall do but is if there be such a thing that propension of its parts to reunite themselves to their whole As in the next place to the Annual motion and the Diurnal these being both made towards one way are very compatible in the same manner just as if we should let a Ball trundle downwards upon a declining superficies it would in its descent along the same spontaneously revolve in it self As to the third motion assigned it by Copernicus namely about it self in a year onely to keep its Axis inclined and directed towards the same part of the Firmament I will tell you a thing worthy of great consideration namely ut tantum abest although it be made contrary to the other annual it is so far from having any repugnance or difficulty in it that naturally and without any moving cause it agreeth to any whatsoever suspended and librated body which if it shall be carried round in the circumference of a circle immediate of it self it acquireth a conversion about its own centre contrary to that which carrieth it about and of such velocity that they both finish one revolution in the same time precisely You may see this admirable and to our purpose accommodate experience if putting in a Bason of water a Ball that will swim and holding the Bason in your hand you turn round upon your toe for you shall immediatly see the Ball begin to revolve in it self with a motion contrary to that of the Bason and it shall finish its revolution when that of the Bason it shall finish Now what other is the Earth than a pensil Globe librated in tenuous and yielding aire which being carried about in a year along the circumference of a great circle must needs acquire without any other mover a revolution about its own centre annual and yet contrary to the other motion in like manner annual You shall see this effect I say but if afterwards you more narrowly consider it you shall find this to be no real thing but a meer appearance and that which you think to be a revolution in it self you will find to be a not moving at all but a continuing altogether immoveable in respect of all that which without you and without the vessel is immoveable for if in that Ball you shall make some mark and consider to what part of the Room where you are or of the Field or of Heaven it is situate you shall see that mark in yours and the vessels revolution to look alwayes towards that same part but comparing it to the vessel and to your self that are moveable it will appear to go altering its direction and with a motion contrary to yours and that of the vessel to go seeking all the points of its circumgyration so that with more reason you and the bason may be said to turn round the immoveable Ball than that it moveth round in the bason In the same manner the Earth suspended and librated in the circumference of the Grand Orbe and scituate in such sort that one of its notes as for example its North Pole looketh towards such a Star or other part of the Firmament it always keepeth directed towards the same although carried round by the annual motion about the circumference of the said Grand Orbe This alone is sufficient to make the Wonder cease and to remove all difficulties But what will Simplicius say if to this non-indigence of the co-operating cause we should adde an admirable intrinsick vertue â—f the Terrestrial Globe of looking with its determinate parts towards determinate parts of the Firmament I speak of the Magnetick vertue constantly participated by any whatsoever piece of Loade-stone And if every minute particle of that Sâ—one have in it such a vertue who will question but that the same more powerfully resides in this whole Terrestrial Globe abounding in that Magnetick matter and which happily it self as to its internal and primary substance is nothing else but a huge masse of Loade-stone SIMP Then you are one of those it seems that hold the Magnetick Phylosophy William Gilbert SALV I am for certain and think that all those that have seriously read his Book and tried his experiments will bear me company therein nor should I despair that what hath befallen me in this case might possibly happen to you also if so be a curiosity like to mine and a notice that infinite things in Nature are still conceal'd from the wits of mankind by delivering you from being captivated by this or that particular writer in natural things should but slacken the reines of your Reason and mollifie the contumacy and tenaceousnesse of your sense so as that they would not refuse to hearken sometimes to novelties never before spoken of But permit me to use this phrase the pusillanimity of vulgar Wits is come to that passe that not only like blind men they make a gift nay tribute of their own assent to whatsoever they find written by those Authours which in the infancy of their Studies were laid before them as authentick by their Tutors but refuse to hear not to say examine any new Proposition or Probleme although it not only never hath been confuted but not so much as examined or considered by their Authours Amongst which one is this of investigating what is the true proper primary interne and general matter and substance of this our Terrestrial Globe For although it never came into the mind either of Aristotle or of any one else before William Gilbert to think that it might be a Magnet so far are Aristotle and the rest from confuting this opinion yet neverthelesse I have met with many that at the very first mention of it as a Horse at his own shadow have start back and refused to discourse thereof and censured the conceipt for a vain Chymaera yea for a solemn madnesse and its possible the Book of Gilbert had never come to my hands if a Peripatetick Philosopher of great fame as I believe to free his Library from its contagion had not given it me SIMP I who ingenuously confesse my self to be one of those vulgar Wits and never till within these few dayes that I have been admitted to a share in your conferences could I pretend to have in the least withdrawn from those trite and popular paths yet for all that I think I have advantaged my self so much as that I could without
double to their Lines 304 FLEXURES The necessity and use of Flexures in Animals for varying of their Motions 232 FOSCARINI Foscarini his Reconciling of Scripture Texts with the Copernican Hypothesis 473 G GENERABILITY Generability and Corruptibility are onely amongst Contraries according to Arist. 26 Generability and Alterability are greater perfections in Mundane Bodies then the Contrary Qualities 44 GEOMETRICAL and Geometry Geometrical Demonstrations of the Triple Dimension 4 Geometrical Exactnesse needlesse in Physical Proofs 6 Aristotle taxeth Plato for being too studious of Geometry 334 Peripatetick Phylosophers condemne the Study of Geometry and why 461 GILBERT The Magnetick Phylosophy of Will-Gilbert 364 The Method of Gilbert in his Philosophy 367 GLOBE Our Globe would have been called Stone instead of Earth if that name had been given it in the beginning 367 GOD. God and Nature do employ themselves in caring for Men as if they minded nothing else 333 An Example of Gods care of Man-kind taken from the Sun 333 God hath given all things an inviolable Law to observe 4â— GREAT Great and Small Immense c. are Relative Terms 334 GRAVITY Grave Vide Body Gravity and Levity Rarity and Density are contrary qualities 30 Things Grave had being before the Common Centre of Gravity 221 Gravity and Levity of Bodies defined 493 GUN and Gunnery The Reason why a Gun should seem to carry farther towards the West than towards the East 148 The Revolution of the Earth supposed the Ball in the Gun erected perpendicularly doth not move by a perpendicular but an inclined Line 155 It is ingenuously demonstrated that the Earths Motion supposed the Shot of Great Guns ought to vary no more than in its Rest. 161 The Experiment of a Running Chariot to find out the difference of Ranges in Gunnery 148 A Computation in Gunnery how much the Ranges of Great Shot ought to vary from the Mark the Earths Motion being Granted 160 H HEAVEN Heaven an Habitation for the Immortal Gods 26 Heavens Immutability evident to Sense 26 Heaven Immutable because there never was any Mutation seen in it 34 One cannot saith Aristotle speak confidently of Heaven by reason of its great distance 42 The substance of the Heavens impenetrable according to Aristotle 54 The Substance of Heaven Intangible 55 Many things may be in Heaven that are Invisible to us 334 There are more Documents in the Open Book of Heaven than Vulgar Wits are able to Penetrate 444 Heaven and Earth ever mutually opposed to each other 480 Which are really the Greater Lights in Heaven and which the lesser 484 Heaven is not composed of a fifth Essence differing from the Matter of inferiour Bodies 494 Heaven is no Solid or Dense Body but Rare 494 Christ at his Incarnation truly descended from Heaven and at his Ascension truly ascended into Heaven 496 Of the First Second and Third Heaven 497 Heaven in the Sense of Copernicus is the same with the most tenuous Aether but different from Paradice which excells all the Heavens 499 HELL Hell is in the Centre of the Earth not of the World 480 HELIX The Helix about the Cylinder may be said to be a Simple Line 7 HYPOTHESIS The true Hypothesis may dispatch its Revolutions in a shorter time in lesser Circles than in greater the which is proved by two Examples 410 I JEST A Jest put upon one that offered to sell a certain Secret of holding Correspondence at a Thousand Miles distance 79 A Jest of a certain Statuary 94 IMPOSSIBILITY and Impossibilities Nature attempts not Impossibilities 10 To seek what would follow upon an Impossibility is Folly 22 INCORRUPTIBILITY Incorruptibility esteemed by the Vulgar out of their fear of Death 45 INFINITY Of Infinity the Parts are not one greater than another although they are comparatively unequal 106 INSTRUMENT and Instruments Instruments Astronomical very subject to Errour 262 Copernicus understood not some things for want of Instruments 338 A proof of the small credit that is to be given to Astronomical Instruments in Minute Observations 351 Ptolomy did not confide in an Instrument made by Archimedes 352 Instruments of Tycho made with great Expence 352 What Instruments are most apt for exact Observations 352 INVENTORS The First Inventors and Observers of things ought to be admired 370 JOSHUAH The Miracle of Joshuah in commanding the Sun to stand still contradicts the Ptolomaick System 456 Joshuahs Miracle admirably agreeth with the Pythagorick Systeme 457 IRON It s proved that Iron consists of parts more subtil pure and compact than the Magnet 370 JUPITER Jupiter and Saturn do encompasse the Earth and the Sun 258 Jupiter augments lesse by Irradiation than the Dog-Star 305 K KEPLER The Argument of Kepler in favour of Copernicus 242 An Explanation of the true Sense of Kepler and his Defence 243 The feigned Answer of Kepler couched in an Artificial Irony 244 Kepler is with respect blamed 422 Keplers reconciling of Scripture Texts whith the Copernican Hypothesis 461 KNOW c. The having a perfect Knowledge of nothing maketh some beleeve they understand all things 84 Gods manner of Knowing different from that of Man 87 The great Felicity for which they are to be envied who perswade themselves that they Know every thing 164 Our Knowledge is a kind of Reminiscence according to Plato 169 L LIGHT Light reflected from the Earth into the Moon 52 The Reflex Light of uneven Bodies is more universal than that of the smooth and why 62 The more rough Superficies make greater Reflection of Light than the lesse rough 65 Perpendicular Rays of Light illuminate more than the Oblique and why 65 The more Oblique Rays of Light illuminate lesse and why 65 Light or Luminous Bodies appear the brighter in an Obscure Ambient 74 LINE The Right Line and Circumference of an infinite Circle are the same thing 342 LAWYERS Contentious Lawyers that are retained in an ill Cause keep close to some expression fallen from the adverse party at unawares 324 LOOKING-GLASSES Flat Looking-Glasses cast forth their Reflection towards but one place but the Spherical every way 39 LYNCEAN The Lyncean Academick the first Discoverer of the Solar spots and all the other Celestial Novelties 312 The History of his proceedings for a long time about the Observation of the Solar Spots 312 M MAGNET Many properties in the Magnet 367 The Magnet armed takes up more Iron than when unarmed 369 The true cause of the Multiplication of Vertue in the Magnet by means of the Arming 370 A sensible proof of the Impurity of the Magnet 371 The several Natural Motions of the Magnet 374 Philosophers are forced to confesse that the Magnet is compounded of Celestial Substances and of Elementary 375 The Error of those who call the Magnet a mixt Body and the Terrestrial Globe a simple Body 375 An improbable Effect admired by Gilbertus in the Magnet 376 MAGNETICK Philosophy The Magnetick Philosophy of William Gilbert 364 MAGNITUDE The Magnitude of the Orbs and the Velocity of the Motions of Planets
for the Reasons alledged admit in many places Expositions far from the Sense of the words and moreover we not being able to affirm that all Interpreters speak by Divine Inspiration For if it were so then there would be no difference between them about the Senses of the same places I should think that it would be an act of great prudence to make it unlawful for any one to usurp Texts of Scripture and as it were to force them to maintain this or that Naturall Conclusion for truth of which Sence Demonstrative and necessary Reasons may one time or other assure us the contrary For who will prescribe bounds to the Wits of men Who will assert that all that is sensible and knowable in the World is already discovered and known Will not they that in other points disagree with us confess this and it is a great truth that Eaquae scimus sint minima pars corum quae ignoramus That those Truths which we know are very few in comparison of those which we know not Nay more if we have it from the Mouth of the Holy Ghost that Deus tradidit Mundum disputationi eorum ut non inveniat homo opus quod operatus est Deus ab initio ad finem One ought not as I conceive to stop the way to free Philosophating touching the things of the World and of Nature as if that they were already certainly found and all manifest nor ought it to be counted rashness if one do not sit down satisfied with the opinions now become as it were commune nor ought any persons to be displeased if others do not hold in natural Disputes to that opinion which best pleaseth them and especially touching Problems that have for thousands of years been controverted amongst the greatest Philosophers as is the Stability of the Sun and Mobility of the Earth an opinion held by Pythagoras and by his whole Sect by Heraclides Ponticus who was of the same opininion by Phylolaus the Master of Plato and by Plato himself as Aristotle relateth and of which Plutarch writeth in the life of Numa that the said Plato when he was grown old said It is a most absurd thing to think otherwise The same was believed by Aristarchus Samius as we have it in Archimedes and probably by Archimedes himself by Nicetas the Philosopher upon the testimony of Scicero and by many others And this opinion hath finally been amplified and with many Observations and Demonstrations confirmed by Nicholaus Copernicus And Seneca a most eminent Philosopher in his Book De Cometis advertizeth us that we ought with great diligence seek for an assured knowledge whether it be Heaven or the Earth in which the Diurnal Conversion resides And for this cause it would probably be prudent and profitable counsel if besides the Articles which concern our Salvation and the establishment of our Faith against the stability of which there is no fear that any valid and solid Doctrine can ever rise up men would not aggregate and heap up more without necessity And if it be so it would certainly be a preposterous thing to introduce such Articles at the request of persons who besides that we know not that they speak by inspiration of Divine Grace we plainly see that there might be wished in them the understanding which would be necessary first to enable them to comprehend and then to discuss the Demonstrations wherewith the subtiler Sciences proceed in confirming such like Conclusions Nay more I should say were it lawful to speak my judgment freely on this Argument that it would haply more suit with the Decorum and Majesty of those Sacred Volumes if care were taken that every shallow and vulgar Writer might not authorize his Books which are not seldome grounded upon foolish fancies by inserting into them Places of Holy Scripture interpreted or rather distorted to Senses as remote from the right meaning of the said Scripture as they are neer to derirision who not without ostentation flourish out their Writings therewith Examples of such like abuses there might many be produced but for this time I will confine my self to two not much besides these matters of Astronomy One of which is that of those Pamphlets which were published against the Medicean Planets of which I had the fortune to make the discovery against the existence of which there were brought many places of Sacred Scripture Now that all the World seeth them to be Planets I would gladly hear with what new interpretations those very Antagonists do expound the Scripture and excuse their own simplicity The other example is of him who but very lately hath Printed against Astronomers and Philosophers that the Moon doth not receive its light from the Sun but is of its own nature resplendent which imagination he in the close confirmeth or to say better perswadeth himself that he confirmeth by sundry Texts of Scripture which he thinks cannot be reconciled unlesse his opinion should be true and necessary Neverthelesse the Moon of it self is Tenebrose and yet it is no lesse lucid than the Splendor of the Sun Hence it is manifest that these kinde of Authors in regard they did not dive into the true Sence of the Scriptures would in case their authority were of any great moment have imposed a necessity upon others to believe such Conclusions for true as were repugnant to manifest Reason and to Sense Which abuse Deus avertat that it do not gain Countenance and Authority for if it should it would in a short time be necessary to proscribe and inhibit all the Contemplative Sciences For being that by nature the number of such as are very unapt to understand perfectly both the Sacred Scriptures and the other Sciences is much greater than that of the skilfull and intelligent those of the first sort superficially running over the Scriptures would arrogate to themselves an Authority of decreeing upon all the Questions in Nature by vertue of some Word by them misunderstood and produced by the Sacred Pen-men to another purpose Nor would the small number of the Intelligent be able to repress the furious Torrent of those men who would finde so many the more followers in that the gaining the reputation of Wise men without pains or Study is far more grateful to humane Nature than the consuming our selves with restless contemplations about the most painfull Arts. Therefore we ought to return infinite thanks to Almighty God who of his Goodness freeth us from this fear in that he depriveth such kinde of persons of all Authority and reposeth the Consulting Resolving and Decreeing upon so important Determinations in the extraordinary Wisdom and Candor of most Sacred Fathers and in the Supream Authority of those who being guided by his Holy Spirit cannot but determin Holily So ordering things that of the levity of those other men there is no account made This kinde of men are those as I believe against whom not without Reason Grave and Holy Writers do so much
while to another and that there is a great difference between commanding a Methametitian or a Philosopher and the disposing of a Lawyer or a Merchant and that the demonstrated Conclusions touching the things of Nature and of the Heavens cannot be changed with the same facility as the Opinions are touching what is lawful or not in a Contract Bargain or Bill of Exchange This difference was well understood by the Learned and Holy Fathers as their having been at great pains to confute many Arguments or to say better many Philosophical Fallacies doth prove unto us and as may expresly be read in some of them and particularly we have in S. Augustine the following words This is to be held for an undoubted Truth That we may be confident that whatever the Sages of this World have demonstrated touching Natural Points is no waies contrary to our Bibles And in case they teach any thing in their Books that is contrary to the Holy Scriptures we may without any scruple conclude it to be most false And according to our ability let us make the same appear And let us so keep the Faith of our Lord in whom are hidden all the Treasures of Wisdom that we be neither seduced with the Loquacity of false Philosophy nor scared by the superstition of a counterfeit Religion From which words I conceive that I may collect this Doctrine namely That in the Books of the Wise of this World there are contained some Natural truths that are solidly demonstrated and others again that are barely taught and that as to the first sort it is the Office of wise Divines to shew that they are not contrary to the Sacred Scriptures As to the rest taught but not necessarily demonstrated if they shall contain any thing contrary to the Sacred Leaves it ought to be held undoubtedly false and such it ought by all possible waies to be demonstrated If therefore Natural Conclusions veritably demonstrated are not to be postposed to the Places of Scripture but that it ought to be shewn how those Places do not interfer with the said Conclusions then it s necessary before a Physical Proposition be condemned to shew that it is not necessarily demonstrated and this is to be done not by them who hold it to be true but by those who judge it to be false And this seemeth very reasonable and agreeable to Nature that is to say that they may much more easily find the fallacies in a Discourse who believe it to be false than those who account it true and concludent Nay in this particular it will come to passe that the followers of this opinion the more that they shall turn over Books examine the Arguments repeat the Observations and compare the Experiments the more shall they be confirmed in this belief And your Highness knoweth what happened to the late Mathematick Professor in the University of Pisa Who betook himself in his old age to look into the Doctrine of Copernicus with hope that he might be able solidly to confute it for that he held it so far to be false as that he had never studied it but it was his fortune that as soon as he had understood the grounds proceedings and demonstrations of Copernicus he found himself to be perswaded and of an opposer became his most confident Defender I might also nominate other Mathematicians who being moved by my last Discoveries have confessed it necessary to change the formerly received Constitution of the World it not being able by any means to subsist any longer If for the banishing this Opinion and Hypothesis out of the World it were enough to stop the mouth of one alone as it may be they perswade themselves who measuring others judgements by their own think it impossible that this Doctrine should be able to subsist and finde any followers this would be very easie to be done but the business standeth otherwise For to execute such a determination it would be necessary to prohibite not onely the Book of Copernicus and the Writings of the other Authors that follow the same opinion but to interdict the whole Science of Astronomy and which is more to forbid men looking towards Heaven that so they might not see Mars and Venus at one time neer to the Earth and at another farther off with such a difference that the latter is found to be fourty times and the former sixty times bigger in surface at one time than at another and to the end that the same Venus might not be discovered to be one while round and another while forked with most subtil hornes and many other sensible Observations which can never by any means be reconciled to the Ptolomaick Systeme but are unanswerable Arguments for the Copernican But the prohibiting of Copernicus his Book now that by many new Observations and by the application of many of the Learned to the reading of him his Hypothesis and Doctrine doth every day appear to be more true having admitted and tolerated it for so many years whilst he was lesse followed studied and confirmed would seem in my judgment an affront to Truth and a seeking the more to obscure and suppresse her the more she sheweth her self clear and perspicuous The abolishing and censuring not of the whole Book but onely so much of it as concerns this particular opinion of the Earths Mobility would if I mistake not be a greater detriment to souls it being an occasion of great scandal to see a Position proved and to see it afterwards made an Heresie to believe it The prohibiting of the whole Science what other would it be but an open contempt of an hundred Texts of the Holy Scriptures which teach us That the Glory and the Greatnesse of Almighty God is admirably discerned in all his Works and divinely read in the Open Book of Heaven Nor let any one think that the Lecture of the lofty conceits that are written in those Leaves finish in only beholding the Splendour of the Sun and of the Stars and their rising and setting which is the term to which the eyes of bruits and of the vulgar reach but there are couched in them mysteries so profound and conceipts so sublime that the vigils labours and studies of an hundred and an hundred acute Wits have not yet been able thorowly to dive into them after the continual disquisition of some thousands of years But let the Unlearned believe that like as that which their eyes discern in beholding the aspect of a humane body is very little in comparison of the stupendious Artifices which an exquisite and curious Anatomist or Philosopher finds in the same when he is searching for the use of so many Muscles Tendons Nerves and Bones and examining the Offices of the Heart and of the other principal Members seeking the seat of the vital Faculties noting and observing the admirable structures of the Instruments of the Senses and without ever making an end of satisfying his curiosity and wonder contemplating
after another Systeme to the discovery of which he doth very earnestly exhort them Now can there a better or more commodious Hypothesis be devised than this of Copernicus For this Cause many Modern Authors are induced to approve of and follow it but with much haesitancy and fear in regard that it seemeth in their Opinion so to contradict the Holy Scriptures as that it cannot possibly be reconciled to them Which is the Reason that this Opinion hath been long supprest and is now entertained by men in a modest manner ad as it were with a veiled Face according to that advice of the Poet Judicium populi nunquam contempseris unus Ne nullis placeas dum vis contemnere multos Upon consideration of which out of my very great love towards the Sciences and my ardent desire to see the encrease and perfection of them and the Light of Truth freed from all Errours and Obscurities I began to argue with my self touching this Point after this manner This Opinion of the Pythagoreans is either true or false If false it ought not to be mentioned and deserves not to be divulged If true it matters not though it contradict all as well Philosophers as Astronomers And though for its establishment and reducement to use a new Philosophy and Astronomy founded upon new Principles and Hypothese should be constituted For the Authority of Sacred Scripture will not oppose it neither doth one Truth contradict another If therefore the Opinion of Pythagoras be true without doubt God hath disposed and dictated the words of of Holy Writ in such a manner that they may admit an apt sense and reconciliation with that Hypothesis Being moved by these Reasons and the probability of the said Opinion I thought good to try whether Texts of Sacred Scripture might be expounded according to Theological and Physical Principles and might be reconciled to it so that in regard that hitherto it hath been held probable it may in after times coming without scruple to be acknowledged for true advance it self and appear in publick with an uncovered Face without any mans prohibition and may lawfully and freely hold a Sacred intelligence with Holy Truth so earnestly coveâ—ed and commended by good Men. Which designe having hitherto been undertaken by none that I know wil I am perswaded be very acceptable to the Studious of these Learnings especially to the most Learned Galilaeo Galilaei chief Mathematician to the most Serene Grand Duke of Tuscany and John Kepler chief Mathematician to his Sacred and invincible Majesty the Emperour and to all that Illustrious and much to be commended Accademy of the Lynceans whom if I mistake not are all of this Opinion Although I doubt not but they and many other Learned Men might easily have found out these or the like Reconciliations of Scriptural expressions to whom nevertheless I have thought fit in respect of that profession which I have undertaken upon the faith of my soul and the propensity that I have towards Truth to offer that of the Poet Nullius addictus jurare in verba Magistri And in testimony of my esteem to them and all the Learned to communicate these my thoughts confidently assuring my self that they will accept them with a Candor equal to that wherewith I have written them Therefore to come to the business All Authorities of Divine Writ which seem to oppose this Opinion are reducible to six Classes The first is of those that affirm the Earth to stand still and not to move as Psal. 92. He framed the round World so sure that it cannot be moved Also Psal. 104. Who laid the Foundations of the Earth that it should not be removed for ever And Ecclesiastes 1. But the Earth abideth for ever And others of the like sense The second is of those which attest the Sun to move and Revolve about the Earth as Psal. 19. In them hath he set a Tabernacle for the Sun which cometh forth as a Bridegroom out of his chamber and rejoyceth as a Gyant to run his Course It cometh forth from the uttermost part of the Heaven and runneth about unto the end of it again and there is nothing hid from the heat thereof And Ecclesiast 1. The Sun riseth and the Sun goeth down and hasteth to the place where he arose it goeth towards the South and turneth about unto the North. Whereupon the Suns Retrogradation is mentioned as a Miracle Isaiah 38. The Sun returned ten degrees And Ecclesiasticus 48. In his time the Sun went backward and lengthened the life of the King And for this reason it is related for a Miracle in the Book of Joshuah that at the Prayers of that great Captain the Sun stood still its motion being forbidden it by him Josh. 10. Sun stand thou still upon Gibeon Now if the Sun should stand still and the Earth move about it its station at that time was no Miracle and if Joshuah had intended that the light of the day should have been prolonged by the Suns splendour he would not have said Sun stand thou still but rather Earth stand thou still The third Classis is of those Authorities which say that Heaven is above and the Earth beneath of which sort is that place of Joel chap. 2. cited by S. Peter in Acts. 2. I will shew wonders in Heaven above and signes in the Earth beneath with others of the like purport Hereupon Christ at his Incarnation is said to come down from Heaven and after his Resurrection to have ascended up into heaven But if the Earth should move about the Sun it would be as one may say in Heaven and consequently would rather be above Heaven than beneath it And this is confirmed For that the Opinion which placeth the Sun in the Centre doth likewise place Mercury above the Sun and Venus above Mercury and the Earth above Venus together with the Moon which revolves about the Earth and therefore the Earth together with the Moon is placed in the third Heaven If therefore in Spherical Bodies as in the World beneath signifies no more than to be neer to the centre and above than to approach the Circumference it must needs follow that for making good of Theological Positions concerning the Ascension and Descension of Christ the Earth is to be placed in the centre and the Sun with the other Heavens in the Circumference and not according to Copernicus whose Hypothesis inverts this Order with which one cannot see how the true Ascension and Descension can be consistent The fourth Classis is of those Authorities which make Hell to be in the Centre of the World which is the Common Opinion of Divines and confirmed by this Reason That since Hell taken in its strict denomination ought to be in the lowest part of the World and since that in a Sphere there is no part lower then the Centre Hell shall be as it were in the Centre of the World which being of a Spherical Figure it must
Fiorentini Weariness more to be feared in the starry Sphere than in the terrestriall Globe Some in arguing first fix in their minds the conclusion beleeved by them and then adapt their reasons to that The motion of the water in ebbing and flowing not interrupted by rest * Pertiche venetiani * Pertiche venetiani * 〈◊〉 †He taketh 〈◊〉 Firmament 〈◊〉 the Sâ—arry Sphere and not as we vulgâ—â—ly receive the word The method observed by Clar. in confuting the Astronomers and by Salviatus in confuting him The greatest and least elevations of the new star differ not from each other more than the polar altitudes the said star being in the Firmnment * 〈◊〉 Astronomical Instruments are very subject to errour * Here the Latine version is erroneous making it a fortieth part of c. * Traguardi In hath not been hitherto proved by any whether the World be finite or infinite The Demonstrations of Aristotle to pâ—ove that the Vniverse is finite are all nullified by denying it to be moveable Aristotle makes that point to be the centre of the Universe about which all the Celestial Spheres do revolve A question is put in case that if Aristotle were forced to receive one of two propositions that make against his doctrine which he would admit It s more rational that the Orb containing and the parts contained do move all about one centre than uâ—on divers If the centre of the World be the 〈…〉 that about which the planets move the Sun and not the Earth is placed in it Observations from whence it is collected that the Sun and not the Earth is in the centre of the Celestial revolutions The mutation of figure in Venus argueth its motion to be about the Sun The Moon cannot seperate from the Earth The annual motion of the Earth mixing with the motions of the other Planets produce extravagant appearances The Systeme of the Universe designed from the appearances Venus very great towards the respective conjunction and very small towards the maintine Venus necessarily proved to move about the Sun The revolution of Mercury concluded to be about the Sun within the Orb of Venus Mars necessarily includeth within its Orb the Earth and also the Sun Mars at its opposition to the Sun shews to be sixty times bigger than towards the conjunction Jupiter and Saturn do likewise encompasse the Earth and the Sun The approximation and recession of the three superiour Planets importeth double the Suns distance The difference of the apparent magnitude lesse in Saturn than in Jupiter andâ— Jupiter than in Mars and why The Moons Orb invironeth the Earth but not the Sun The probable situation of the fixed stars Which ought to be accounted the sphere of the Vniverse Rest the annual motion and the diurnal ought to be distributed betwixt the Sun Earth and Firmament In a moveable sphere it seemeth more reasonable that its centre be stable than any other of its parts Granting to the Earth the annual it must of necessity also have the diurnal motion assigned to it Discourses more than childish serve to keep fools in the opinion of the Earths stability A declaration of the improbability of Copernicus his opinion Reasons and discourse in Aristarcus and Copernicus prevailed over manifest sence Mars makes an hot assaults upon the Coperâ—â—can Systeme The Phaenomena of Venus appear contrary to the Systeme of Copernicus Another difficulty raised by Venus against Copernicus Venus according to Copernicus either lucid in it self or else of a transparent substance Copernicus speaketh nothing of the small variation of bigness in Venus and in Mars The moon much disturbeth the order of the other Planets Answers to the three first objections against the Copernican Systeme The reason whence it happens that Venus and Mars do not appear to vary magnitude so much as is requisite The operations of the Telescope accounted fallacies by the Peripateticks Shining objects seem environed with adventitious rayes The reason why luminous bodies appear enlarged much the more by how much they are lesser Superficial figures encreasing proportion double to their lines Objects the more vigorous they are in light the more they do seem to increase An easie experiment that sheweth the increase in the stars by means of the adventitious rays Jupiter augments lesse than the Dog-star The Sun and Moon increase little It is seen by manifest experience that the more splendid bodies do much more irradiate than the lesse lucid The Telescope is the best means to take away the irradiations of the Stars Another second reason of the small apparent increase of Venus Copernicus perswaded by reasons contrary to sensible experiments Mercury admitteth not of clear observations The difficulties removed that arise from the Earths moving about the Sun not solitarily but in consort with the Moon The Medicean Stars areas it were four Moons about Jupiter The Principal scope of Astronomers is to give a reason of appearances Copernicus restored Astronomy upon the suppositions of Ptolomy What moved Copernicus to establish his Systeme Inconveniencies that are in the Systeme of Ptolomy The annual motion of the Earth most apt to render a reason of the exorbitances of the five Planets The Sun it self testifieth the annual motion to belong to the Earth The Lyncaean Academick the first discoverer of the Solar spots and all the other celestial novelties The history of the proceedings of the Academian for a long time about the observation of the Solar spots * Duumviro * This Authors true name is Christopher Scheinerus a Jesuit and his Book here meant is intituled Apelles post tabulam * La mia villa delle Sâ—lue A conceipt that came suddenly into the minde of the Academian Lyncaeus concerning the great consequence that followed upon the motion of the Solar spots Extravagant mutations to be observed in the motions of the spots foreseen by the Academick in case the Earth had the annual motion The first Accident to be observed in the motion of the Solar spots and consequently all the rest explained The events being observed were answerable to the predictions Though the annual motion assigned to the Earth answerth to the Phaenomena of the solar spots yet doth it not follow by conversion that from the Phaenomena of the spots one may infâ—r the annual motion to belong to the Earth The Pure Peripatetick Philosophers will laugh at the spots and their Phaenomena as illusions of the Chrystals in the Telescope If the Earth be immoveable in the centre of the Zodiack there must be ascribed to the Sun four several motions as is declared at length * I should have told you that the true name of this concealed Authour is Christopher Scheinerus and its title Disquisitiones Mathematica * i. e. the Ecliptick Instances of a certain Book Ironically propounded against Copernicus Supposing the annual motion to belong to the Earth it followeth that one fixed Star is bigger than the whole grand Orb. Tycho his Argument grounded upon a false Hypothesis
Christianus ita noverit ut cirtissima ratione vel experientiâ teneat Turpe autem est nimis perniciosum ac maxime cavendum ut Christianum de his rebus quasi secundum Christianas litteras loquentem ita delirare quilibet infidelis audiat ut quem admodum dicitur toto Caelo errare conspiciens risuÌ„tenere vix possit non tam molestum est quod errans homo derideretur sed quod auctores nostri ab tis qui foris sunt talia sensisse creduntur cum magno exitio corim de quorum salute satagimus tanquam indocti reprehenduntur atque respuuntur Cum enim quemquam de numero Christianorum eaiâ—re quam ipsi optime norunt deprehenderint vanam sententiam suam de nostris libris asserent quo pacto illis Libris credituri sunt de Resurrectione Mortuorum de spe vitae eternae Regnoque Celorum quando de his rebus quas jam experiri vel indubitatis rationibus percipere potuerunt fallaciter putaverint esse conscriptos y Quid enim molestiae tristiaeque ingerant prudentibus fratribus tenerarâ—j praesumpiores satis dici non potest cum si quando de falsa prava opinione sua reprehendi convinci caeperint ab iis qui nostrorum librorum auctoritate apertissima falsitate dixerunt eosdnm libros Sanctos unde id probent proferre conantur vel etiam memoriter quae ad testimonium vâ—lere arbitrantur multa inde verba pronunciant non intelligentes neque quae loquuntur neque de quibus affirmant If this passage seem harsh the Reader must remember that I do but Translate * 〈…〉 On it s own Axis * Lux ejus colligit convertitque ad se omnia quae videntur quae moventur quae illustrantur quae calescunt uno nomine ea quae ab ejus splendore continentur Itaque Sol 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 dicitur quod omnia congreget colligatque dispersa * Si enim Sol hic quem videmus eorum quae sub sensum cadunt essentias qualitates quaeque multa sint ac dissimiles tamen ipse qui unus est aequaliterque lumen fundit renovat alit tuetur perficit dividit conjungit fovet faecunda reddit auget mutat firmat edit movet vitaliaque facit omnia unaquaque res hujus universitatis pro captu suo unius atque ejusdem Solis est particeps causasque multorum quae participent in se aequabiliter anticipatas habet certe majori raticne c. Solem stetisse dum adhuc in Hemisphaerio nostro supra scilicet Horizontem existeret Cajetan in loco * Or Poles * Gen. Chp. 〈◊〉 v. 1. * Psal. 24. 2. * Psal. 137. 1. * Chap. 1. v. 4 to 9. Psal. 104. v. 5. * Shelter * Officium * In vita ejus * Followers of that Learned Kings Hypothesis * That is 5000 miles eight of these making an Italian or English mile of a 1000. paces every pacâ— containing 5. Feet * Chap. 1. v. 4. The Motion of the Earth not against Scripture Faith is more certain than either Sense or Reason * 2 Pet. 1. 19. * Or Primum Mobile * Cardan de rerum vaâ—iet Lib. 1. Cap. 1. * P. Clavius in ultima suor Operum editione The Author first Theologically dâ—fendeâ—h the â—arths Mâ—bility approved by â—ary of the Moderns b Or In Sole posuit tabernaculum suum according to the Translation our Author followeth In Sphericall Bodies Deorsum is the Centre and Sursum the Circumference Hell is in the centre of the Earth not of the World Heaven and Eartâ— are always 〈◊〉 opposed to each other After the day of Judgment the Earth shall stand immoveable * Circa Cardines Coeli Luke 16. Alia sunt notiora nobis alia notiora natura vel secundum se Arist lib. 1. Phys. * Aut ad Umbram Which are really the great Lights in Heaven The Sun Moon and Stars are one the same thing The Earth is another Moon or Star Why the Sunne seemeth to us to move not the Earth Aeneid 3. a Eccles. c. 1. v. ult b Chap. 3. v. 11. c 1 Cor. c. 4. v. 5. d 1 Cor. c. 13. v. 12. e 1 John c. 3. v. 2. f 1 Cor. c. 13. v. 12. g Ecclesiast 15. 3. h 1 Cor. c. 2. v. 2. i Isa. c. 48. v. 17. 1 Thess. 4. Joshua c. 10. ver 12. * expected Isa. c. 38. v. 8. â— Several Motions of the Earth according to Copernicus The Earth Secundum Totum is Immutable though not Immovable The Earth cannot Secundum Totum remove out of its Natural Place The Natural Place of the Earth The Moon is an Aetherial Body The Earths Centre keepeth it in its Natural Place Gravity and Levity of Bodies what it is All Coelestial Bodies have Gravity and Levity Compressive Motion proper to Gravity the Extensive to Levity Heaven is not composed of a fift Essence differing from the matter of inferior Bodies Nor yet a Solid or dense Body but Rare * Delle Macchie solarj * Vnius Corporis simplicis unus est motus simplex et huic dua species Rectus Circularis Rectus duplex à medio ad medium primus levium ut Aeris Ignis secundus gravium ut Aquae Terra Circularis quiest circa medium competit Coelo quod neque est grave neque leve Arist. de Coelo Lib. 1. * Vide Copernicum de Revolutionibus Coelest Simple Motion peculiar to only Simple Bodies Right Motion belongeth to Imperfect Bodies and that are out of their natural Places Right Motion cannot be Simple Right Motion is ever mixt with the Circular * aequabilis * Even Circular Motion is truly Simple and Perpetual Circular Motion belongeth to the Whole Body and the Right to its parts Circular and Right Motion coincedent and may consist together in the same Body The Earth in 〈◊〉 sense it may 〈…〉 be said 〈…〉 the lowest 〈◊〉 of the World Christ in his Incarnation truly descended from Heaven and in his Asceâ—sion truly ascended into Heaven 2 Cor. c. 12. v. 3. Whether in the body or out of the body I cannot tell The Sun is King Heart and Lamp of the World himself being 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 absolutely independent The Aenigma of Plato a Circa omniâ—m Regem sunt omnia Secunda circa Secundum et Tertia circa Tertium Vide Theodo de Graec. affect curat lib. 2. Sâ—euch lib. de Parennj Philoso Eccles. c. 1. 2. 3. and almost thoout * Quod fiunt vel sunt sub sole Heaven according to Copernicus is the same with the most tenuous Aether but different from Paradice which surpasseth all the Heavens a Exod. 25. 31. b My Authour following the vulgar Translation which hath an Eligance in some things beyond ours cites the words thus Facies Candelabrum ductile de auro mundissimo Hastile ejus Calamos Sphaerulas ac Lilia ex ipso procedentia c verse 12. d or Spheres e Though our Authour speaketh here positively of nine Months c. Fathers are not agreed about the period of this planet nor that of Mercury as you may see at large in Ricciolus Almagest nov Tom. 1. part 1. l. 7. sect 3. cha 11. num 11. page 627. where he maketh Venus to consummate her Revolution in neer 225 dayes or 7 12 Mon. and Mercury in about 88 dayes or 3 Months in which he followeth Kepl. in Epitome Astronom p. 760. f vers 33 34. g 1 Kings c. 7. v. 49. 2 Chron. c. 4. vers 7. h Exod. 28. 33 34 39. v. 24 25 26. i Sap. c. 18. v. 24. k Exod. c. 28. v. 6 9 17 36. l Or totus Orbis Terrarum as the vulgar Translation hath it m Numb c. 20. v. 5. n Joel c. 1. v. 12. o Hagg. c. 2. v. 19. p Deut. c. 8. v. 8. q 1 Kings c 7. v. 20. 2 Kings c. 25. v. 17. 2 Chro. c. 3. v. 15 16. c. 4. v. 12. 13. Jerem. c. 52. v. 21 22. r Gen. c. 1. v. 1. s Psal. 67. v. 6 7. * Psal. 9 v. 5 6. * Institutionum omnium Doctrâ—narum * De Oraculis * De Divinatiâ—-ne artificiosa * De Divinatiâ—-ne Naturali Cosmologica a Nella continuatione dell Nuntio siderio b Lâ—ttera al P. Abbaâ—â— D. B. Castelli D'Aâ—cetro li. 3. Decemb. 16 9. c De Motu Aquanâ— â—ib 2. Prop. 37. p. 191. * And as is at large demonstrated by that most excellent and Honourable personage Mr. Boile in the industrious experiment of his Pneumatical Engine * Artesia * Commentarius beareth many senses but in this place signifieth a certain Register of the quantities of the Waters in the several publique Aquiducts of Rome which word I find frequently used in the law-Law-books of antient Civilians And by errogation we are to understand the distribution or delivering out of those stores of Water * A Coyn of Pope Julius worth six pence * Or Sluice * In Pregadi a particular Council the Senators of which have great Authority * A Venice Brace is 11 16 of our yard * A River of that name * I. Savii dell ' Acque a particular Council that take care of the Lakes and other Aquatick affairs * He here intends the Demonstrations following at the end of the first Book * Deeper * Lib. 1. * The Countrey or Province lying round the City heretofore called Latium * Or Lordship * The Popes Exchequer * Polesine is a plat of Ground almost surrounded with Bogs or waters like an Island * People of Ferrara * In Chanels made by hand * The inch of these places is somewhat bigger than ours * Of Adriano * Larghezza but misprinted
them and the rather for that to your benefit you may read them in Gilbert onely to encourage you to the perusal of them I will set before you in a similitude of my own the method that he observed in his Philosophy I know you understand very well how much the knowledg of the accidents is subservient to the investigation of the substance and essence of things therefore I desire that you would take pains to informe your self well of many accidents and properties that are found in the Magnet and in no other stone or body as for instance of attracting Iron of conferring upon it by its sole presence the same virtue of communicating likewise to it the property of looking towards the Poles as it also doth it self and moreover endeavour to know by trial that it containeth in it a virtue of conferring upon the magnetick needle not onely the direction under a Meridian towards the Poles with an Horizontal motion a property a long time ago known but a new found accident of declining being ballanced under the Meridian before marked upon a little spherical Magnet of declining I say to determinate marks more or lesse according as that needle is held nearer or farther from the Pole till that upon the Pole it self it erecteth perpendicularly whereas in the middle parts it is parallel to the Axis Furthermore procure a proof to be made whether the virtue of attracting Iron residing much more vigorously about the Poles than about the middle parts this force be not notably more vigorous in one Pole than in the other and that in all pieces of Magnet the stronger of which Poles is that which looketh towards the South Observe in the next place that in a little Magnet this South and more vigorous Pole becometh weaker when ever it is to take up an iron in presence of the North Pole of another much bigger Magnet and not to make any tedious discourse of it assertain your self by experience of these and many other properties described by Gilbert which are all so peculiar to the Magnet as that none of them agree with any other matter Tell me now Simplicius if there were laid before you a thousand pieces of several matters but all covered and concealed in a cloth under which it is hid and you were required without uncovering them 〈…〉 a guesse by external signes at the matter of each of them and that in making trial you should hit upon one that should openly shew it self to have all the properties by you already acknowledged to reside onely in the Magnet and in no other matter what judgment would you make of the essence of such a body Would you say that it might be a piece of Ebony or Alablaster o◠Tin SIMP I would say without the least haesitation that it was a piece of Load-stone SALV If it be so say resolutely that under this cover and scurf of Earth stones metals water c. there is hid a great Magnet forasmuch as about the same there may be seen by any one that will heedfully observe the same all those very accidents that agree with a true and visible Globe of Magnet but if no more were to be seen than that of the Declinatory Needle which being carried about the Earth more and more inclineth as it approacheth to the North Pole and declineth lesse towards the Equinoctial under which it finally is brought to an Aequilibrium it might serve to perswade even the most scrupulous judgment I forbear to mention that other admirable effect which is sensibly observed in every piece of Magnet of which to us inhabitants of the Northern Hemisphere the Meridional Pole of the said Magnet is more vigorous than the other and the difference is found greater by how much one recedeth from the Equinoctial and under the Equinoctial both the parts are of equal strength but notably weaker But in the Meridional Regions far distant from the Equinoctial it changeth nature and that part which to us was more weak acquireth more strength than the other and all this I confer with that which we see to be done by a small piece of Magnet in the presence of a great one the vertue of which superating the lesser maketh it to become obedient to it and according as it is held either on this or on that side the Equinoctial of the great one maketh the self same mutations which I have said are made by every Magnet carried on this side or that side of the Equinoctiall of the Earth SAGR. I was perswaded at the very first reading of the Book of Gilbertus and having met with a most excellent piece of Magnet I for a long time made many Observations and all worthy of extream wonder but above all that seemeth to me very stupendious of increasing the faculty of taking up Iron so much by arming it like as the said Authour teacheth and with arming that piece of mine I multiplied its force in octuple proportion and whereas unarmed it scarce took up nine ounces of Iron it being armed did take up above six pounds And it may be you have seen this Loadstone in the Gallery of your Most Serene Grand Duke to whom I presented it upholding two little Anchors of Iron SALV I saw it many times and with great admiration till that a little piece of the like stone gave me greater cause of wonder that is in the keeping of our Academick which being no more than of six ounces weight and sustaining when unarmed hardly two ounces doth when armed take up 160. ounces so as that it is of 80. times more force armed than unarmed and takes up a weight 26. times greater than its own a much greater wonder than Gilbert could ever meet with who writeth that he could never get any Loadstone that could reach to take up four times its own weight SAGR. In my opinion this Stone offers to the wit of man a large Field to Phylosophate in and I have many times thought with my self how it can be that it conferreth on that Iron which armeth it a strength so superiour to its own and finally I finde nothing that giveth me satisfaction herein nor do I find any thing extraordinary in that which Gilbert writes about this particular I know not whether the same may have befallen you SALV I extreamly praise admire and envy this Authour for that a conceit so stupendious should come into his minde touching a thing handled by infinite sublime wits and hit upon by none of them I think him moreover worthy of extraordinary applause for the many new and true Observations that he made to the disgrace of so many fabulous Authours that write not only what they do not know but what ever they hear spoken by the foolish vulgar never seeking to assure themselves of the same by experience perhaps because they are unwilling to diminish the bulk of their Books That which I could have desired in Gilbert is that he had
been a little greater Mathematician and particularly well grounded in Geometry the practice whereof would have rendered him less resolute in accepting those reasons for true Demonstrations which he produceth for true causes of the true conclusions observed by himself Which reasons freely speaking do not knit and bind so fast as those undoubtedly ought to do in that of natural necessary and lasting conclusions may be alledged And I doubt not but that in processe of time this new Science will be perfected with new observations and which is more with true and necessary Demonstrations Nor ought the glory of the first Inventor to be thereby diminished nor do I lesse esteem but rather more admire the Inventor of the Harp although it may be supposed that the Instrument at first was but rudely framed and more rudely fingered than an hundred other Artists that in the insuing Ages reduced that profession to great perfection And methinks that Antiquity had very good reason to enumerate the first Inventors of the Noble Arts amongst the Gods seeing that the common wits have so little curiosity and are so little regardful of rare and elegant things that though they see and hear them exercitated by the exquisite professors of them yet are they not thereby perswaded to a desire of learning them Now judge whether Capacities of this kind would ever have attempted to have found out the making of the Harp or the invention of Musick upon the hint of the whistling noise of the dry sinews of a Tortois or from the striking of four Hammers The application to great inventions moved by small hints and the thinking that under a primary and childish appearance admirable Arts may lie hid is not the part of a trivial but of a super-humane spirit Now answering to your demands I say that I also have long thought upon what might possibly be the cause of this so tenacious and potent union that we see to be made between the one Iron that armeth the Magnet and the other that conjoyns it self unto it And first we are certain that the vertue and strength of the stone doth not augment by being armed for it neither attracts at greater distance nor doth it hold an Iron the faster if between it and the arming or cap a very fine paper or a leaf of beaten gold be interposed nay with that interposition the naked stone takes up more Iron than the armed There is therefore no alteration in the vertue and yet there is an innovation in the effect And because its necessary that a new effect have a new cause if it be inquired what novelty is introduced in the act of taking up with the cap or arming there is no mutation to be discovered but in the different contact for whereas before Iron toucht Loadstone now Iron toucheth Iron Therefore it is necessary to conclude that the diversity of contacts is the cause of the diversity of effects And for the difference of contacts it cannot as I see be derived from any thing else save from that the substance of the Iron is of parts more subtil more pure and more compacted than those of the Magnet which are more grosse impure and rare From whence it followeth that the superficies of two Irons that are to touch by being exquisitely plained filed and burnished do so exactly conjoyn that all the infinite points of the one meet with the infinite points of the other so that the filaments if I may so say that collegate the two Irons are many more than those that collegate the Magnet to the Iron by reason that the substance of the Magnet is more porous and lesse compact which maketh that all the points and filaments of the Loadstone do not close with that which it unites unto In the next place that the substance of Iron especially the well refined as namely the purest steel is of parts much more dense subtil and pure than the matter of the Loadstone is seen in that one may bring its edge to an extraordinary sharpnesse such as is that of the Rasor which can never be in any great measure effected in a piece of Magnet Then as for the impurity of the Magnet and its being mixed with other qualities of stone it is first sensibly discovered by the colour of some little spots for the most part white and next by presenting a needle to it hanging in a thread which upon those stonynesses cannot find repose but being attracted by the parts circumfused seemeth to fly from those and to leap upon the Magnet contiguous to them and as some of those Heterogeneal parts are for their magnitude very visible so we may believe that there are others in great abundance which for their smallnesse are imperceptible that are disseminated throughout the whole masse That which I say namely that the multitude of contacts that are made between Iron and Iron is the cause of the so solid conjunction is confirmed by an experiment which is this that if we present the sharpned point of a needle to the cap of a Magnet it will stick no faster to it than to the same stone unarmed which can proceed from no other cause than from the equality of the contacts that are both of one sole point But what then Let a Needle be taken and placed upon a Magnet so that one of its extremities hang somewhat over and to that present a Nail to which the Needle will instantly cleave insomuch that withdrawing the Nail the Needle will stand in suspense and with its two ends touching the Magnet and the Iron and withdrawing the Nail yet a little further the Needle will forsake the Magnet provided that the eye of the Needle be towards the Nail and the point towards the Magnet but if the eye be towards the Loadstone in withdrawing the Nail the Needle will cleave to the Magnet and this in my judgment for no other reason save onely that the Needle by reason it is bigger towards the eye toucheth in much more points than its sharp point doth SAGR. Your whole discourse hath been in my judgment very concluding and this experiment of the Needle hath made me think it little inferiour to a Mathematical Demonstration and I ingenuously confesse that in all the Magnetick Philosophy I never heard or read any thing that with such strong reasons gave account of its so many admirable accidents of which if the causes were with the same perspicuity laid open I know not what sweeter food our Intellects could desire SALV In seeking the reasons of conclusions unknown unto us it is requisite to have the good fortune to direct the discourse from the very beginning towards the way of truth in which if any one walk it will easily happen that one shall meet with several other Propositions known to be true either by disputes or experiments from the certainty of which the truth of ours acquireth strength and evidence as it did in every respect