join B C by a Line then by 4. of the first the Triangle B H C shall be equal to the Triangle F S G and shall be equal to the Portion F N G by the 17. of Archimedes de Quadratura Parabolae by the help of the first Conception of Euclide I do the like of the Portion of F G X to whom by an equal Triangle O P K then I draw P Q equally distant O K and R V equally distant O P by 31 of the first of Euclide then by 41. of the same O P R shall be half of the Superficies O V. Now then I somewhat portract C H then upon B H I constitute a Superficial of equidistant sides having an Angle of B H A by 44. of the first of Euclide twice assumpt to the Diameter of the first Superficies A P B then by 41. of the same by the first conception of the Trigon A B C shall be equal of the Superficies F G N X. granted which is the intent Aristotle to say the Truth was an excellent searcher of things yet I will not say as some say which have never read the the Works of Aristotle or understand them not that every Word of Aristotle is almost a Sentence and that Aristotle was the God of Phylosophers and that he never erred in one Word but was divine in all things Such miserable men if they knew what it were to speak with Demonstration and what by Experience to the Sense would never have said such things For Sense simply in those things which are not properly sensible we are oftentimes deceived And whereas we cannot perceive the Deception by the Mean of that simple sense then it seemeth to us that the thing cannot be and that it is not in very Deed as it appeareth to the sense As for Example who is he that thinking not a Reflex Form on the Superficial Water immovable to be seen of the same greatness as is by a right Longitude by the mean of a Diaphane gathered of a Radical Line incident and Reflex whereas this is false by G D of the 6 of Vitellio For the Superfities of the Water is Spherical as sheweth Aristotle 2 de Câ—â—lo cap. 4. But better Archimedes in the second Proposition De subsidentibus aquae And therefore when any Star appeareth to us above the Horizon yet is it not indeed as it appeareth by this Demonstration Let the Star be I the Horizon R A T the Earth E A M. whose Center is A and the sight G the Vapours O E then whereas the radical Line passing from any rare thin or transparent in any transparent of more thickness maketh a Perpendicular by the 45. of the Second of Vitellio it is manifest therefore that the Star I to be seen by the Line I D E which Line shall be crooked because that simple Air is thinner then Vapours and Fire thinner then Air. Also the matter or substance of Heaven is thinner then Fire by the 50. of the 10 of Vitellio Furthermore the higher part of the Air is thinner then the lower part the same I say also of Water and Fire if we may call Fire the highest part of the body and near unto the concavity of the Moon and of every Superior part of Elements And so the Star by the Line D E seemeth to be above the Horizon in the point V. But Vitellio also in his 10 Book in the Proposition 49. teacheth perspectively and how it may be instrumentally proved how the Stars may be seen in the Horizon without their proper places by reason of Incurnation or crooking of the Beams whereof it followeth that they do not Mathematically define the Horizon which say it is the Terminer or ender of the sight and of the greatest Circles of the Sphere whereas by the Demonstration before the Circle ending of the sight is cutting the Sphere in two unequal Portions and that the higher Portion be greater then the lower For if the Horizon be the ender of the sight and one of the greatest Circles then the Earth is not equally about the Center or middle of the World or else the middle of the World is without the Earth But if the Earth doth equally compass about the middle ergo the ender of the sight is not of the greatest Circles in the Sphere or contrarity Therefore if we shall see any Star above the ender of the sight we should not therefore think it to be in the twelfth station of Heaven this is to be understood by reasonable manner for the Virtue of the Star appeareth chiefly in the great Circle whose Pole is Zenith passing by the 90 Degree of the Equinoctial from the Intersection or dividing of the same with the Meridian toward the East Furthermore the difference between the ender of the sight and the greater Circle is not only one Diameter of the Star but of Degrees which if it were not we could by no means use the Proposition 49 of Vitellio and therefore it was no small Error of them that said that the Horizon is the ender of the fight and one of the greatest Circles in the Sphere and that ever the middle of Heaven appeareth unto us for evermore then half appeareth unto us for the Incurvation or crooking of the Beams But he that will see more Examples of these things let him read the 4th Book of Vitellio and the Tenth and in some parts the Second and 5th of the same in all of which he shall see somewhat how easily we may be deceived by this sense but the like of other Senses is not to be doubted Therefore not without weak and slender judgment they call Aristotle so Divine a Prince of Phylosophy and Divine Peter Arches did very wisely give Commendation to Aristotle proportionally and no further but only to God forasmuch as it is humane to err Aristotle also might sometime fail We having thus throughly discoursed of Proportions Local we shall now next fall upon the swift Motion by the Art of Navigation which will occasion us to traverse many rare Mathematical Secrets This most swift Motion to the common sort of men seemeth incredible for that the same may be done by sailing in a Ship or other Vessell against whatsoever course of any Outragious Flood or River and against the most furious Winds whatsoever they are even also in the deepest Winter and greatest Sourges of Water Neither is it strange if it be incredible to the unexpert For the common people count that for a Miracle which the expert Mathematicians know to be natural and easie for if it should be propounded to the ignorant people that any man might in the midst of the Waters and Floods descend to the bottom of the River Rhene his Apparel remaining dry and no part of Body wet and also to bring with him burning fire from the bottom of the Water it should seem to them to be ridiculous and an impossibility Which nevertheless in the year 1538. in Toleto a City
J or in the eighth proportion so then the moving of the body A V J shall in the seveth proportion be swifter then the body M because the resistance of the body M is subdupla and to the body A V J is suboctupla by the seventh of Archimedes de insidentibus Aquae But by the aforesaid demonstration the body M shall be moved in the same time which the body A V I. Wherefore by the the first conception of the mind added upon Euclide by Companus the proposition is dear The like reason is also of violent motions taking the proportion of the moving strengths and taking away the proportion of the half or middle Also whereas are two equal Angles about the Horizon or under but in contrary motion of Nature because violent motion is swifter in the begining than in the end and the contrary chanceth in the motion of Nature for with violent motion the motion of Nature is ever somewhat mixt if Horizontically or Angulerly it shall be above or beneath the Horizon and Nature worketh so much until it bring violent motion to some end But if the Perpendicularly Violence shall be made about the Horizon and towards the place which that body naturally moveth unto then Nature cannot strive against or withstand but that Violence doth ever go with it in respect of the end from whence Furthermore by the aforesaid it is manifest that to be false which Aristotle saith 7 Phisic in the last Chapter where he saith if A be that which moveth B and B that which is moved and C the Longitude whereby and D in which the motion is that is to say in equal time and power equal A the half of B shall move by the double of C and C in the half of D for so shall be the similitude of the reason c. That it is false I will thus demonstrate Let us first imagine two bodies as before in any mean or middle homogenie c. And let ns for example M and N and that M be double in quantity to the Body N and that the weigt of N be with one of the weight of M and also that the body A V I be equal to the body M in quantity and in likeness or kind of the body N then by common Science the body of A V I shall be double in heaviness to the body M. And granting that the body M by double in heaviness above the half then shall the body A V I be quadruple in heaviness above the said half Wherefore the resistance taken away let be left the time in which the body A V I be quadruple in heaviness above the said half Wherefore the resistance taken away let be left the time in which the body A V I in the same time shall be moved the body N by the aforesaid Or if in the same time the body N shall be moved with the body M yet the space by which N shall be triple to that by which M. for the reasons are all one of violent motions The same shall precisely come to pass if instead of the excess of weight above the half we shall take the virtue or power of moving c. as before Arristotle likewise erreth in his 4 Physic Chap. 8. Where he discourses de Vacue saying that the same or else all one shall be the proportion of motions of any body by divers Elements As if the Air be in subtilty double to the water in double time B. The mean shall Pass to that time in which by the mean D and C the it me shall be double of the time E and C. Now to shew the Error of Aristotle let us first understand a body to pass through Water by natural motion as for example by a granted space let us also imagine that body in double to exceed the water in the weight and that the Water in heaviness exceed the Air in double proportion then the granted body shall be quadruple to the Air. Wherfore in the haviness the resistance of time taken away in the which the motion of that body in the Air by equal space to that by the which in Water to the time wherein by Water in the granted space is moved the proportion shall be subtriple and not subduple as Aristotle affirmeth Aristotle also erreth in the same Chapter supposing that if motion should be granted in voide the same or all one should be the reason of time to time as is between moving bodies which is impossible by the aforesaid For those bodies should be moved is equal time although they should be of divers kinds forms and bigness By which place also is easie to gather that the mind of Aristotle was that the proportion of motion to motion is the same thing which greatnesses have between them according to the heaviness and lightness simply But that this also may the more clearly be understood imagine the bodies M and N in void and that the body N be of the same weight which A V I but of divers kinds and consequently of divers bigness then whereas those bodies have no resistance there is no doubt but that they shall be moved by equal time by equal space I will take therefore the body A V I of the kind of the body N but of quantity of the body M. Now then by the mean of the true method of the demonstration before shewed A V I and N shall be moved in equal time with the body N by equal space Wherefore by the first conception in the same in the M wherefore it followeth c. Furthermore also where Aristotle 7. Phific speaketh of the comparison of motions saying that a right Line is not comparable to a crooked Line because there should be found some right Line equal of circuler Line either greater or less For whereas by reason of the definition given by him in the 6 Phisic to the swiftness and slowness of motion it seemeth to him that it cannot be that circular motion should be comparable to right motion In the which he is manifestly deceived and chiefly thinking that a right Line cannot be found equal greater or lesser to the circular Line Whereas Archimedes in his first proposition in Geometry sheweth the contrary and that by Mathematical demonstration and not by the opinion of Aristotle For Archimedes sheweth there by what means we may find a right Line greater or less then any circular Line constituting figures of right Lines without or within the circle c. But some men may say that though a right Line may be granted greater or less than any circular line yet that the same cannot be found equal whereas in the fifteenth of Euclide the third is shewed that a greater Angle may be found then is the Angle of a Contingence and that by the motion of the right Line of the greater Angle passage is made to the right Line contingent or touching the circle yet that it cannot be that with the contigent Line it
of the Water which is yet better proved in the manner as followeth Take a certain quantity of Water and sprinkle it by drops upno a dry or dusty Table so shall the drops partly shew a Sperical form remaining but if the Table before be never so little wet with Water the drops sprinkled thereon shall float abroad and keep no sperical or round form by reason of the moisture that the Table hath received before of the Water It hath oftentimes happened that certain Towns and Lands have been drowned by the Rivers overflowing near unto them Nevertheless how much soever such Waters increase or rise there is no danger untill great Showres falling from Heaven do thorowly wet the Banks Ramperts and Calseys of such Rivers For when they as we have said are thorowly imbibed with moistness they cause the overflowing and breach whereof followeth the overflowing and drowning of the Region And this may suffice for Advertisement Now I shall instance the aforesaid experiment shewed at Toleto by two Gre ks who taking a Chalderon of great Capacity the Mouth turned downwards and so hanging it in the Air by Ropes they fastened certain Boards Posts or Shelves in the middest of the Chaldron where they placed themselves with the fire Then to make it hang stedfastly and equally they compassed the Circumference brim or border thereof with Leaden Plummets every side equally and made of equal weight least any part of the circumference of the mouth of the Chaldron except it were equally softly let down into the water should sooner touch the water then the whole circumference For so should the water easily overcome the air inclosed in the chaldron and resolve it into moisture But if by due proportion the Chaldron thus prepared be fair and softly let down into the water the air inclosed in the chaldron by resistance of the water shall violently make it self place not admitting the water to enter So the men there inclosed shall so long remain dry in the middest of the water untill success of time do by respiration debilitate and consume the inclosed Air turning it into gross humidity ingrossed by the coldness and moistness of the water but if in due time the chaldron be softly and equally drawn out of the water the men shall remain dry and the fire not extinct as it was then experimented which also may be thus proved take a Cup or Glass of a certain quantity the circumference of the mouth whereof shall be broader then the circumference of the bottom In the mouth let be fastened a little stick tying thereunto a thread on the stick fasten a little candle of wax whose light may come only to the middest of the cup least as much nearness of the water might suffocate the candle Then proportionably as in the former experiment put the cup with a burning candle into a Vessel full of water and in due time draw it out softly and equally so that no part of the mouth of the circumference thereof be drawn out before the whole or speedily so shall the candle remain in extinct Let not therefore the Ignorant condemn our writings before they know what may be done by experience it is now no miracle when it is known to be natural and thus it is in all other Sciences and Experiments which the common people think to be impossible As that the salt water of the Sea may be made fresh and Potable to be drunk which nevertheless may be done naturally as hath been often proved divers ways Some do this as is written in Gemma Philosophica putting the salt water in a Vessel plaistered or crusted over with clean wax which distilling through the strait or narrow pores thereof leaveth the salt which for its grossness cannot pass thereby The same may be done better by a Canon or Pipe filled with Gravel or little stones that the salt water poured thereon may divers times pass through that Pipe into another Vessel Furthermore Let these ignorant People take notice that the Arts and Sciences have all of them in the latter Ages either been revived from decay or reduced to use or brought forward to perfection so many secrets of nature and rare conclusions having been found out by and imparted to the World by Albertus Magnes Levinus Lemnius Fernelius Fracostorius Babtista Porta Cornelius Agrippa Cardanus Trithemius Delrio and infinite others besides our own Countreymen such Inventions as have been singular and artificial for the use ease delight or ornament of Mankind as a number of Mecanical Mathematical and Musical Instruments Chimneys Stirrups Paper Spectacles Parcellan Perspective-Glasses Fining of Sugars Hand-mills Glones Hats Bands Watches besides divers excellent Works in Stuffs and Silks in Linnens in Hangings in Carpets with many others particularly set down by Polydor Virgil de Inventoribus rerum and Pancirellus in his novo repâ—rta aâ—d Cardanus in his 17 Book de Artibus artificiosisque râ—bus to whom notwithstanding much more might be easily added for as truth is the Daughter of time so are useful Inventions too as rightly Manilius Sed cum Longae dies acuit mortalia corda Et Labor ingenium miseris dedit sua quenque Advigilare sibi jussit fortuna premendo Seducta in varias certarunt pectora curas Et quodcunque sagax tentundo râ—perit usus In commune bonum commentum Lâ—ta tenere But when the tract of time had whet mens wits And Industry had moulded them by fits Fortune pressing each Man to endeavour To free himself from misery together They bend their Minds to search out sundry things And what is found by observation sage They chearfully impart from age to age I will only specifie some other of the rarest Artificial Works of this latter Age comparable for Workmanship with the best of the Ancients Peter Ramas tells us of a wooden Eagle and an Iron Fly made by Regiomontanus a famous Mathematician of Norimburgh whereof the first in Imitation of Architas his Dove met the Emperor a good way off coming towards it and having saluted him returned again waiting on him to the City Gates The second at a Feast whereto he had invited his loving Friends flew forth of his hand and taking a round returned thither again to the great Astonishment of the Beholders both which the Divine Pen of the Noble Du Bartas hath excellently expressed Why should I not that wooden Eagle mention A Learned Germans late admired Invention Which mounting from his fist that framed her Flew far to meet an Almain Emperour And having met him with her Noble Train And weary Wings turning about again Followed him close unto the Castle-gate Of Norimburgh whom all their shews of State Streets hang'd with Arms Arches curious built Grey-headed Senate and Youths gallantise Graced not so much as only this devise He goes on and thus describes the Fly Once as this Artist more with Mirth than Meat Feasted some Friends whom he esteemed great From under 's hand an Iron Flie flew out
THE Accomplish'd Sea-mans DELIGHT CONTAINING 1. The great Mistery of Nature demonstrated by Art as the Flux and Reflux Increase and Decrease Access and Recess Ebbing and Flowing of the Water of the Sea 2. The Closset of Magnetical Miracles unlocked the properties and secrets of the Loadstone revealed serving not only for Sea Affairs but also for Travellers by Land 3. Directions for Sea-men in distress of Weather also the right use of the Magnitical Needle and how to Manage the Sayling Compass and the rest of the Instruments of Chiefest Use in the Art of Navigation 4. The Resolver of Curiossities being a profitable Discourse of Local as also of the swift Motion of the Art of Navigation Of the due proportion to be observed in the Building of Ships likewise rare Inventions of several Engons With a perfect Discovery of other admirable Mathematical Secrets and for their clearer Explaination are Adorn'd with most significan and proper Figures First Read then after that despise Thy Prejudice and be more wise LONDON Printed for Benj. Harris at the Anchor and Marinor in Thredneedle Sreet over against the Royal Exchange 1686. Licensed October the 10th 1685. Rob. Midgley THE Accomplish'd Sea-mans DELIGHT c. THough the Psalmist tells us that the Lord hath Founded the Earth upon the Seas and Established it on the Floods Psal 24.2 Because for the more Commodious living of Man and Beasts he hatâ— made a part of it higher then the Seas or at least restrained their Incursion upon it so as now they make but one intire Globe yet because the Waters in the first Creation covered the Face of the Earth I will begin with them The mother of Waters the great deep hath undoubtedly lost nothing of her ancient bounds or depth but what is impaired in one place is again restored to her in another The Rivers which the Earth sucked from her by secret Veins it renders back again with a full Mouth and the Vapours which the Sun draws up empty themâ—elves again into her Bosome according to that Expression of Du Bartas The purest Humour in the Sea the Sun Exhales in the Aire which there resolved anon Returns to Water and descends again By sudry ways into his Mother main Her motion of Ebbing and Flowing and of high Springs and dead Neapes are still as certain and constant as the Changes of the Moon and Courses of the Sun Her native saltness and by reason thereof her strength for the better supporting of Navigable Vessels is still the same so likewise the Rivers the Daughters thereof either hold on their wonted Courses and Currents or what they have diminished in one Age or place they have again recompenced and repayed in another Because things move and are changed without which such and so great matters could not well be disposed we are to think the Earth doth not alwayes remain in the same state without addition or diminution neither yet the Water as if they were alwayes boudned within the same lists especially seeing their mutual Change is natural and kindly but rather that much Earth is turned into Water and contrariwise no less Water into Earth it is not then to be wondered at if that part of the Earth which is now habitable was formerly overflowed with Water and that again which now is Sea was sometimes habitable as amongst Fountains some are dryed up and some spring forth afresh which may also be varifyed of Rivers and Lakes wherewith accords that of Ovid Met. 15. Vidi Ego quod fuerat quondam seti disima tellus Esse Fretum What was firm Land sometimes that have I seen Made Sea and what was Sea made Land again On Mountain tops old Anchors found have been And Sea-fish shells to lie far from the main Plaines turn'd to Vales by Waterfalls the Down By overflows is chang'd to Champain Land Dry ground e're while now moorish seen doth drown And Fens again are turn'd to thirsty Sand. Her Fountains now hath Nature opened Their shut up springs which first did flow amain By Earth-quakes Rivers of sin issued Or dryed up they have sunk down again Nor in one place perpetually to tarry All things in every Age for ever more do very And Nature changeth still the course she once begun And will her self undoe what she of Old hath done Which though it be true in many yet those great ones of Indus and Ganges and Danubius Rhenes and Nylus are littie or nothing varied from the same courses and currents which they held Thousand of years since as appears in their discriptions by the Ancient Geographers but above all methinks the constant rising of Nylus continued for so many Ages is one of the greatest wonders in the World which is so precise in regard of time that if you take of the Earth adjoyning of the River and preserve it carefully that it come neither to be wet nor wasted and weigh it daily you shall find it neither more nor less heavy till the seventeenth of June at which day it beginneth to grow more ponderous and Augmenteth with the Augmentation of the River whereby they have an infalible Knowledge of the state of the Deluge This Mr. George Sandys reports and Alpinus a Physitian names it as a common experiment Whereas heretofore mention hath been made of the Sea and flowing of Waters and divers other motions it may be convenient to add hereunto the sayings and writings of the most expert Learned Person Fredericus Delphinus Doctor of Arts and Physick and publick professor of the Mathematical Sciences in Padua touching the flowing and reflowing or increase or decrease otherwise also named access and recess that is coming and going or ebbing and flowing of the Water of the Sea Which flowing and reflowing some do also name the false rest or quietness or inordinate motion of the Water of the Sea And albeit divers men have Treated of this Subject yet forasmuch as some of their writings are somewhat too dark and not easie of Men to be understood I have thought necessary partly out of their Writings and partly by my own Industry more clearly and largly to Treat thereof that the same may be the better understood of all men Therefore for the more easie understanding of these two manner of motions of the Water of the Sea following the moving of the Sun and Moon to the moving of the Primum Mobile The first moveable is first to be known that wheresoever a man is on the Earth his Horizon ever cutteth or divideth the Heaven to him into two halfs and the one half of Heaven is ever above his Horizon and the other half beneath and whereas in the half of a Sperical or round Body are contained two quarters two shall ever be above his Horizon and two beneath those that are above the Horizon are called diurnall or day quarters and they that are under the Horizon are called the Nocturnal or Night quarters Of these four quarters of Heaven are two of which is made the flowing
be said hereafter following It happeneth as I have said that the Water of the Sea doth sometimes wander or decline from the order already prescribed yet commonly and for the most part keepeth the due order Such manner of declining is after two sorts for there is either disorder or error in the hour of the begining of the motion of the flowing or reflowing or in the middest of the motion that is that they have greater or lesser courses then at other times or otherwise greater or lesser increases or decreases the errour coming in the hour of motion may proceed from the causes as by reason of the situation of the Region or by reason of the Bodies supercelestial or by change of the Air. By reason of situation of Regions chanceth diversity only in the hour of the begining of the flowing because the begining thereof hath respect to the Horizon or is by respect to the Horizon for in the begining of reflowing is no diversity or errour because the begining of the reflowing is by respect to the Meridian Circle Again by reason of the situation of the Region diversity happeneth thus that is that either the Region is under the Equinoctial Circle or without it And if it be under the Circle because they have a right Horizon and the days there are always equal with nights at all times of the year That we have said of divers hours of the begining of flowing is certainly true But Regions distant from the Equinoctial because they have a winding or slope Horizon in them the beginings of flowings are as in Regions under the Equinoctial only in two times of the year that is to say in the Spring time or Equinoctial Vernal and in the time of Autumne or Equinoctial Autumnal that is to say about the middest of the Month of March and about the middest of the Month of September But in other times of the year or from the Vernal Equinoctial by the whole Summer until the Equinoctial Autumnal it is otherwise because the begining of the day flowing if the flowing be before noon that is about the morning or shall be later then it ought to be that is to say more of the day then is in Regions under the Equinoctial and that is because that in such Regions the day begineth sooner or the Sun riseth sooner then in the Regions which are under the Equinoctial for the declining of the obliqe or side Horizon although these Regions be under one and the same Meridian and if the begining of the day flowing be after noon that is about evening then such begining shall be sooner then it is in Regions under the Equinoctial that is to say in fewer hours of the day because that then the Sun faleth later then in Regions which be under the Equinoctial but the begining of the night flowing if it be before midnight it is sooner in the said places or Regions that is to say in less time of the Night or in less time after the setting of the Sun then in the Regions under the Equinoctial because that then the night begineth to them afterwards And if the begining of the night flowing be after midnight that is towards the day it shall be later that is of more hours or more near the day then is in Regions under the Equinoctial because the Sun riseth sooner to them then to those that are under the Equinoctial And this diversity groweth so much that sometimes it chanceth to see two flowings in one day and none in the night which happeneth from the inequality of the days with their nights For in how much the Artificial day shall be longer then his night so much diversity and errour ariseth more evidently Therefore in the longest days of the year such diversity shall appear manifestly But from the Equinoctial Autumnal by all Winter untill the Equinoctial Vernal it is contrary because the begining of the day flowing if it be before noon that is about the morning then shall it be sooner then it should be that is to say in fewer hours of the day then it should be in a right Horizon for then the day begineth later or the Sun riseth later to them that have a winding or crooked Horizon And if such flowing shall be after noon that is about evening then the begining of such flowing shall be latelyer that is more towards the evening or nearer to the setting of the Sun then in Regions which are under the Horizon for in a side or crooked Horizon the night is sooner and the Sun falleth sooner then in a right Horizon Also the begining of the night flowing if it shall be before midnight it shall be later and more in the night then in Regions under the Equinoctial because then the night shall sooner begin in the crooked Horizon then in the right because the Sun first falleth in the crooked Horizon then in the right And if the begining of the night flowing shall be after midnight that is towards the day then such begining of flowing in the crooked Horizon shall be sooner that is more before the day or before the rising of the Sun then shall be in Regions which are under the Equinoctial And such diversity groweth so much that sometimes shall be two flowings in the night and none in the day And this chanceth from the inequality and increase of the night above his day for in how much the night shall be longer then his day so much the more groweth such diversity and therefore such diversity shall appear greatest in the longest night of the year wherefore by the aforesaid it is manifest that how much the nearer we shall be to the Equinoctial so much the less shall appear the diversity in the hour of the begining of the flowing of the Water And how much the Sun shall be nearer to the standings or stayings of the Sun called Solititium or the longest days and longest nights so much greater and more certain shall be the diversity and shall appear more manifestly Furthermore diversity happeneth by reason of the Heavenly Bodies and Errour not only in the begining of flowing but also of reflowing For when any of the great and Luminous Stars as are Venus and Jupiter shall be above the Sun or Moon they help them in moving of the Water of the Sea and therefore by this means also they leave their due order Likewise as we have said by reason of the change of the Air oftentimes chanceth diversity and errour in the beginings of flowing and reflowing for the violent disposition of Winds vehemently blowing as well near as far off removeth the Courses of Water from their due order somtimes hastening the flowing and somtimes the reflowing and somtimes staying and slacking them likewise There chanceth also errour in the midst of the motion of Waters for as well courses of Waters as also flowings and reflowings somtimes keep not the due motion For as it is said the disposition of Winds may either increase or
The Compass Needle being the most admirable and useful Instrument in the World is both amongst â—urs and other Nations for the most part so bungerly â—nd absurdly contrived as nothing more And therefore as I have treated of the nature and use of the Magnet I have thought good also to employ my best endeaâ—our to advance this noble Instrument towards its highest perfection being the principal thing by which the worthy effect of the Magnet is made most profitable unto Mankind herein five things are to be consideâ—ed the substance that it is made of the form the weight the capitell the pin it standeth upon the substance in any wise ought to be pure Steel and not â—ron for most assuredly Steel will take at the least ten times more virtue than Iron can do but especially if it hath its right temper And that is this heat it in the fire untill it be past red hot that it be whitish hot and quench it in cold Water suddenly so is it Brick in a manner or Glass it self and is at that time incapable of the virtue of the Load-stone Then must you laying it upon a plain Table warily rub with fine Sand all the black colour from it if before you put into the fire you anoint it with black Soap it will scale white it self theâ— heat a Bar of Iron well near red hot and holding one end of the Needle with a small pair of Tongues lay the other end upon the hot Bar and presently you shall see that end turn from a white to a yellowish and afterwards to a blewish colour then take that end with your Tongues and do the like to the other thrusting it forwards upon the Bar untill the colour of the whole Needle become blewish then throw it on a Table and let it cool it self and so is he of the excellent temper and most capable to receive the greatest power from the Load-stone If this seem too curious especially for some fashions of Needles then use but the Hammer hardening as Workmen call it which is well near as good As concerning the form divers men are of divers minds some use a kind of a square one others a Loop I mean an extended Ovall form and this is most common but now a days a narrow streight plate being somewhat broader in the middle is in great request of these I hold the Loop or Ovall form if it be well made to be the best which is that if it be Steel his ends be welded together having a Lattin narrow plate issuing from the capitell unto the middle of the two sides of the Loop and there rivited and riviting if it be handsomely shoulered in by the Workman is better than soadering because having fitted the Lattin plate bearing the capitell unto the Loop you may first put your Loop into his temper and then rivet this unto him afterwards which otherwise would be spoiled in the fire and the wide Loop is better then the narrow or the streight plate and that for two reasons The one is because as in a Magnet it self the force that is in the whole body sheweth it self most strongly in his two Poles even so this being a Magnetical Body doth the like in his ends which are his Poles and the end of a wide compassed Loop being longer than of a narrower of the same length in the Axis must needs contain so much the more Vertue The other reason is because it supposeth the Flie in his Circular Motion more equally ballanced then the other and therefore were it not for some other Inconveniences a true Circle were best of all which that except you mark the two places that you would have for the North and South very curiously you shall never give him the right touch yea very exceeding hardly although that you do mark them and also the Lattine Stay that holdeth the Capital would be exceeding long and a superfluous burden but the best form of all as I take it in all respects is this A true Circle having his Axis going out beyond the Circle at each end narrow and narrower unto a reasonable sharp point and being pure Steel as the Circle it self having in the midst a convenient Receptacle to place the Capital fitly in This Circle must have four very small holes drilled through it equally distant each from the other for the four Cardinal Points and in both the two Points that issue without the Circle being for North and South of equal distance between the Circle and the end of the Point two more if it be a large one otherwise one is enough according to the following Figure And this Needle is most fit to be used for the Observation of the Variation without any Flie as I will hereafter shew Whensoever you will set this Needle unto the Flie you must put the Capital through the Center of the Flie very precisely and placing the Points of the Diameter where you will have them thrust little small pins through the upper place of the Flie and those smalâ— holes in the Needle the heads of the pins will shew you if the Flie be larger then your Needle at whaâ— Point your Needle standeth and bowing the body oâ— your pins being thrust through those little holes close to the Card below will keep it steady at that place and from warping also And so four pins at the four Cardinal Points will serve the turn Again If you please to place this Needle upon the upper end of the Card according to Stevinius thorough the Center in the bottom of the Flie and the Needle placed and fastened on the top or upper face of the Card. But if you will have a Magnetical Needle to serve only for one size of a Flie the best way is instead of the two pins in the end of the Axis to have a couple of little half Staples and a Flower-de-Luce on one of them as you see in the Loop revitted there That â—in turning about the Needle they may still keep the Flie close unto it and so fasten it upon a Skrew upon the Capital wheresoever you please As for his weight it must be according to his largeness and the weight is one principal cause the very large Compasses are unprofitable For the weight of the weight of the large Card and the heavy Needle pressing upon the pin will cause the Motion of the Flie to be dull and uncertain and therefore let the Pasteboard be no heavier then you must needs and for the size of six Inches Diameter of your Paste-board and a Needle of that length I know that a Needle of half an Ounce weight and half a quartern at the uttermost if a good Workman have it in hand will be fully sufficient of what Form soever The Capital ought to be Lattin and Hammer-hardned well and truly boared not too shallow but of a good convenient depth and wideness at the bottom fitâ—ing the pin it standeth upon at the top The Pin ought to be either
a Meridian Circle with the Horizon wherein fasten two other pins on which it may easily move and divide the Poles most exactly to the Poles of the World the which if it come well to pass rejoyce that then you have found one of the greatest Miracles of Natural things For you shall by this means see the Ascendent the place of the Sun and the like c. at every Moment But if it fall not out according to your desire you ought not to impute that to the Art but to your own ignorance and negligence For if you execute and perform all things duly and aright according to Art you need not to doubt the success How these Instruments by this Stone may be framed by the which may be found the Azimuths of the Sun and Star that is to say Verticall Circles it shall not here be necessary to shew forasmuch as the same is easily done by the Marriners Compass or by the Box with the Magnes or Load-stone inclosed and floating above the Water with a pin erected and in the uppermost part divided into 360 parts after the manner of Astronomy That you may easily find out the chief points of any Load-stone of what forme soever you must make a respective or declinatory Needle of an Inch or thereabouts in length and giving him his touch fasten him by the Axis upon a little forked stick or any thing like it that the Needle may have free scope then offer the Stone as we said before near the Needle turning of it round about and immediatly you shall see the North of the Needle as it is as yet commonly called because it pointeth toward the North point directly unto the true North end of the Stone as soon as it commeth near unto it and as you turn away the end of the Stone the Needle will point somewhat towards it till the South end of the Stone approacheth as we have in part declared for then will the Needle wheele about the Axis and point directly with his South and to the South ef the Stone But if you hold the Needle near to the Stone in such sort that it cannot turn about at liberty then the force of the Stone may soon change the properties of the ends of the Needle that the one point which was North shall become South and that other which was South shall become North yet the thing it self is easily discerned for the Northerly end will alwayes hang lower And wheresoever the Needle being held nearer to the stone doth stand parrallell unto it not inclineing with either end towards the stone there directly under the middle of the Needle the North and the South properties of the stone do divide and part themselves This matter is much better performed with a small narrow Load-stone of half an Inch more or less in length haveing in the ends his due points of North and South and wrought over with silk of two colours from the middle to each end as for Example Yellow and White that part which pointeth over to the North let it be wrought over with White and the other with Yellow Then if you hang that in the middle by a fine silk thred and apply it to any other Load-stone the South end of the one will readily find out the North end of the other and contrarywise In like manner with this Magnetical Instrument you may see two pretty conclusions The one if you touch a knife with the end of a forceable Load-stone whether it be North or South and hang this wrought on by a silke thred in the middle that it may hang freely the one end will crave towards the point of the knife and the other will not abide it The other is if you hang it end long with the true North end right over the North end of a forcible Load-stone or with the South end over the South end of the other you shall see that it will in no wise being let down come unto the North point of the Load-stone but will contrary to Phylosophycal Principles that heavy things should tend directly downwards by the means of the Silk Thread swim or wheele the end of the Load-stone in the Air yea and lift it self somewhat upwards rather then perpendicularly light down upon it yea that it will doe although you place a Plate of Silver or Brass or any such thing between the stone and it self The second way is to take a Thread of a common Sowing Needle and touch the point of it with the North end of a Load-stone whose points you would find out holding the Needle about an Inch from it and in turning the stone about you shall presently see the Needle point to the North end when by your turning it cometh near The contrary effect ensueth if you touch the point of the Needle with the other end of the stone wherein you may behold that ancient conceived and of late years maintained opinion of the contrariety of the Load-stone and the Theamedes to be no otherwise then a contrary property of one and the self same Magnes The third way is to breake off the point of a Sowing Needle half an Inch or longer if the stone be good but not above a quarter of an Inch if it be a base stone lay it upon the stone and move it to and fro upon the superficies thereof being smooth with the Needles point forwards and as it cometh near any of the two points of force it will raise it self more and more but being brought unto the point it self it will stand there strait upright if the stone be ragged this cannot be practiced otherwise of all other it is the most certain way Now whether it be your North or South end the effect will soon declare The fourth way is that you having an ordinary Dyal or a Sailing Compass or any Magnetical Needle standing on a sharp point hold near thereunto the stone â—â—â—ning it in your hand then will the North end of the Needle I mean the end that pointeth to the North respect the true North point of the stone The fifth way is also if you touch a common soâ—ing Needle the longer the better and put it through a little piece of Câ—â—k not bigger then may well bare it up so that by the means thereof it may swim in a Bason of Water the same if you offer the stone unto it will shew the like effect And here it is to be remembred that none other way whatsoever will more readily or truely define the Magnetical Meridian And therefore as it is very requisite for many purposes that every Traveller by Land but more especially by Sea should always have if he may an aequinoctial Dyal with him so would I not with that any of them should be without some Sowing Needles touched with a good stone which will both serve the proper uses of Sowing without impairing their touch for it is open Air and Rust that are the greatest Enemies thereof and at any
time with a piece of Cork or a dry Stick in the Water the Magnetical Meridian may be seen a matter though mean and trivial in shew yet between whiles of so great importance that it may serve to save many mens lives A sixt way is also if you prepare a little round Load-stone of a quarter of an Inch Diameter or thereabouts but it must be a very good one having his Poles marked and sitted in such manner that it easily turn about in a little Frame according to the following Picture The like also in his manner will come to pass if you have a small declinatory Needle in a frame in this manner Then by moving it in his Frame all over the stone the North Pole of this will find the South of the other and likewise will the South the North of the great one for it is not in outward shew one Magnet and another as is between a Magnet and a Magnetical Needle the contrary ends of the Magnet will covet in their motion to meet together but the end of the Needle which turneth North will come unto the North of the stone For in very truth it is the South point of the Needle even as the Magnet it self being placed in a Wooden Dish in Water will turn with his North end to the South and with his South end Dish and all towards the North. The like effect will also follow if you hang as aforesaid a small Load-stone in the middle of a small Silk Thread and that it may freely turn without impediment according to its nature but this property it will shew quicker or flower according unto the goodness of the substance and fitness of the form The best form for this purpose is the extended â—â—all having his Poles precisely in the ends If his Poles be some pretty distance the one end towards the East of the stone and the other as much towards the West this stone in his length will not point to the Magnetical North and South as otherwise he would but unto some other point of the Horizon yea following this experiment in this manner you may make him stand in any one Point of the Compass only you ought to abridge the stone in his length that he may â—ome somewhat nearer to a circular form so that is diameter of North and South being through the Magnetisme of the Earth the cause of this motion â—ay be so much the longer in comparison of the Mass of â—he stone and consequently more effectual After the â—ke manner you may so touch the Wyars of a Comâ—ass that the Flower de Luce of the flie stand unto what point of the Horizon you please although the â—iameter of the Wyars do still remain fixed under the Flower de Luce and the South point of the Card. Finally to conclude this point with some Magnetical Delights if you touch two Sowing Needles in a contraâ—y manner that is the point of the one Northrely and â—he other Southerly and set them with their Corks the one at the one side of a Bason of Water and the other at the other you shall see them as quickned with Vital Spirit even so to move the one end towards the other at the first fair and softly but when they draw near they will rush together as it were with a kind Violence the point of the one striking precisely at the point of the other you must place the Needle whose point is â—ouched for the North on the South fide of the Bason otherwise the heads and not the points will run together a thing far more worthy of admiration then all the self movers of any Dadalus or Architaâ— Tarentinus and more strange to behold then the Connexion of â—ron Rings combined by Virtue Magnetical whereat St. Augustine so much and that justly did wonder Another excellent and secret conclusion upon this stone pretended to be found out in these latter times â—s that by touching two Needles with the same stone they being severally set so as they may turn upon two round Tables hanging on their Borders the Alphabet written Circuler wise if two Friends agreeing upon the time the one at Paris the other at London having each of them their Table thus equally fitted be disposed upon certain days and at certain hours to confer it is to be done by turning the Needle in one of the Tables to the Alphabet and the other by Sympathy will turn it self in the self same manner in the other Table though never so far distant Which conclusion if infallibly true may likewise prove of good and great consequence howsoever I will set it down as I find it described by Faminanus Arada Lib 2. Prolus 6. in imitatton of the Stile and Vain of Lucretius Magnesi genus est Lapidis mirabile cuâ—si Corpora ferrisue plura stilo admoveris inde Non modo nim notumque tratiant que semper ad Vrsam Quis lucet nicina polo se vertere tentent Verum etiam mira inter se ratione modoque Quotquot eum Lapidem tetigere stiti simul omnes Conspirare situm motumque vide bis in unum Vt si forte ex tiâ— aliquis Romae moveatur Alter ad hunc motum quamvis sit disitus longe Arcano se naturai foedere vertat Ergo age quid si scire notes qui distat amicum Ad quem nulla accedere possit Epistola sume Plunum Orbem patulumque notas Elementaque primo Ordine quo discunt pueri describe per oras Extremas Orbis medioque repone jacentem Qui tetigit Magneta stylum ut versatilis inde Litterulam quumcunque velis coâ—ingere possit Hujus ad exemplum simuli fabricaveris Orbem Margine descriptum munitumque indice ferri Ferri quod motum Magnete accipit ab illo Hunc Orbem dissessurus sibi portet Amicus Conveniatque prius quo tempere quiesue diebus Exploret stylus an trepides quid ve indice signes His ita compositi si clam cupis alloqui amicum Quem procui a Te Te terrai distinet ora Orbi adjunge manum ferrum versatile tracta Hic disposta vides Elementa in Margine toto Queis opus est ad verba notis hunc dirige ferrum Litterulesque modo hanc modo et illam euspride tange Dum ferrum per eas iterumque sterâ—mque rotando Componas singulatim sensa omnia mentis Mira fides longe qui distat cerâ—it amious Nullius impulsu trepidare volubile ferrum Nunc huc nunc illuc discuere conscius tuaret Observatque stoti ductum sequiturque legendo Hinc atq hinc Elementa quibus in verba coactis Quid sit opus sentit ferroque interprete discit Quin etiam cum stare stylum videâ— ipse vicissim Si quae respondenda putat simili ratione Litterulis verie tactis rescribit amico O Vtinam haec ratio scribendi prodeâ—t asu Cautior et citior properat Epistola nullas Latronum veritae insidias fluviosque Morantes Ipse