pole it self it is quite vanished away for from thence all the points of the Horizon are only South if it be at the South pole and North from the South and therefore in that place the Instrument of declination is far more sure then the Horizontical Compass And as in the poles themselves there is no direction at all so of necessity near unto them it must be a very confused direction Those two places that are called the poles have no strength of themselves as aforesaid but as it is contributed unto them of the whole As in a Magnet if you break off a piece of a contrary end the end that is lest will be according to that proportion diminished in his strength and the polar piece and the polar piece that is broke off be it never so little will have two poles as well as the great so that the two parts will have four poles two of them North and two of them South Put this little piece that was broken off in his place again and then each piece will loose one of his poles at the very same instant and the whole will have but two poles the one North and the other South as at the first Again if you cut off of one side a piece of the Load-stone that is brought into a round of an Ovall form having his poles marked in their due places at each end presently both ends will be abridged of part of the force which they had and the poles themselves will be removed unto the other side from the places that were marked and those marks will stand but for idle ciphers in comparison of that they were before Again take a Magnet of an old or an extended Ovall form I do still exemplify in these because they are of all others as I have often admonished for all Magnetical proof the most excellent forms and set marks on the two poles take a fine Needle or any streight small Wyar and set it on the Equinoctial mean thereby the middle between the two ends of the stone then will it point directly towards each pole if the stone be sound without any flaws or any other gross substance as may be intermingled with it and if you thrust this Needle towards either end according to his own direction he will trace you a circle right over both of these marked poles which is the true Meridian of the stone But if this stone hath on either of the sides any imperfection when the Needle cometh to the edge or brink thereof it will swarve somewhat towards the sounder side and will point to neither of the true poles And if a circle be drawn according to his pointing as he standeth still in that place this shall be a respective Meridian of that stone proper unto that place and the poles The respective poles differing from the true Meridian of the stone and his poles Now if you thrust the Needle farther towards the end upon the brink of this imperspection it will not point as before but either further off or nearer to the true poles and will give his direction for a new respective Mâ—ridian and new respective poles and in such manner infinitely if you place the Needle in the middle of this imperfection equally distant from the sound parts then will it indeed point towards the end of the stone and the consequence hereof is the main reason and that towards the middest of the Ocean and likewise of any great continent there is no variation Thus may you especially in a round Load-stone as in a lively example see the true causes of all the variations that are in the whole World reckoning as much space as the Ocean covereth to be some imperfection in the body of the whole in respect of the Horizontical motion of the Compass For the evidence of the truth hereof let a man examine generally the variations of the most expert Navigators although by reason of the diversities of the sets of their Compasses and unfitness and unapt handling of their Instruments they seldom times agree amongst themselves observed in the Atlantick Ocean from the Aequatour unto the parts of Norway all along the East Coast from the Meridian of the Azores so as far North as hereunto has been discovered and he shall find the ordinary practice to testifie the truth hereof as also after the same sort from the Aequatour Southward unto the streights of Magellan and all along the back side of America in the South Sea on the East Coast on the Cape of Bona Speranza and he shall perceive the like agreeement but in Sailing from the cap of Bona Speranza farther farther Eastward that sometimes they do find it otherwise the cause is the different manner of the situation of the South as yet undiscovered continent And whereas in the middest of the Atlantick Ocean about 30 Leagues West from the Azores they find no variation at all no mervail thereof for it is about the middle distance between the two great Continents of America and Ours Wherefore the round Load-stone is significantly termed by Doctor Gilbert Terrella that is a little or rather a very little Earth for it representeth in a little small modell as it were the admirable properties Magnetical of the huge Globe of the Earth herein also we may behold the reason why the Magnetical Needle varieth least in the Aequinoctial and most towards the pole and in the poles themselves giveth no direction at all for proof hereof take a Needle and place it on the Aequinoctial of the stone there you shall see stand equally ballanced and very strongly so that if you turn him from the direction as soon as you let him go he will presently again turn to it The reason is because each pole doth equally strengthen his correspondent end of the Needle Move this Needle towards either of the poles then doth the nearer pole strengthen his end of the Needle but the farther because of the distance cannot do the like unto his but very weakly and this Needle will not stand any more equally ballanced as it did in the Aequinoctial but that end next to the pole will couch down and the other will rise up for on the North side of the Aequatour the true South end is predominant and on the other the North end hath the Mastery And that this is also in the Earth it self all our late Travellers confirm unto us by their daily experience and all the very Artizans and Needle-makers must needs be daily witnesses of it As for Example let any Workman in our Climate make a Needle for a Dyal when he hath fitted it and placed it on the pin that it may stand thereon equally ballanced and parallel to the Horizon touch it with the Load-stone then presently that which pointeth towards the North will hang down yea although you touch only with the South end and will not stand as before the touch equally ballanced and parallel to the Horizon except that you cut
â—ings 〈…〉 a great piece 〈…〉 â—he great one whose parâ—icieâ—â— they are 〈…〉 great one should do the 〈◊〉 namely to take in so many times their own weights Also very often it is seen that Magnets being of like form and weight but of divers kinds the one will take up more Iron of himâ—elf without the Cap and yet the other give a far stronger touch but then if you do fit both of them accordâ—ngly with Caps he which gave the stronger touch will take up more Iron then the other The principal â—orce of the Load-stone well proportioned passeth in 〈◊〉 direct Line from the middle of his substance being as it were a center through his two ends or points which are the imaginary likes of his chiefest force from which center there isse infinite others also through all parts of the superficies of the stone on either side between the two extream points of the middle all which on either side of the middle being of one nature and property in respect of their touch are exceedingly different in strength for that still waxeth less and less as it approacheth continually nearer and nearer the middle where at length in the middle between the two ends it utterly fainteth and cometh to nothing The Load-stone communicateth his property to the Iron or Steel that is touched with it so far forth as the Iron or Steel which is touched hath the ability to receive and so that good skill in the touching be observed Steel is far better then Iron and receiveth a far strongen touch and much more effectual The purer Steel so much the better and if it be Iron the purer likewise the better always regarding that both of them be very smooth and clean and have their due temper The principal property in common use is the shewing of North and South in the Horizon with the appendants thereunto belonging which is more apparant more strong and more commodious in the Iron and Steel that is touched then it is in the stone it self because the substance of them may be filled and cut away and drawn into any form that we like or approve of our selves which the substance of the stone will not permit The Lood-stone is of such a nature that every piece broken off and seperated from the whole hath all the properties of the whole the same several points North and South and ability also for the touch like in kind though not of equal power according to the quantity and proportion of the Piece and the part of the Stone that it is taken from and this property in a meaner sort hath touched the Needle and the Wyar of a compass also That one stone may draw another lay the one upon a board or box in the Water that it may freely float and hold another in your hand If then the North part of the stone which you hold in your hand you turn towards the South part of that which floateth in the box or otherwise the South part to the North the floating stone shall turn towards your hand and if contrarywise you turn the like part to his like that is to say the South part to the south c. the floating Stone shall fly from you By this experiment certain Phisitians are confuted who dispute on this manner If Scemmonea draw unto it choler by Similitude or Likeness of Nature Ergo much more should one Magnet draw another rather then Iron So that what they assume falsely we have now taught to be true The like judgment is of the long slender Iron which is rubbed with the Stone For if in the Water it be laid on a light piece of Wood or a straw or such like so that it may freely float upon the Water the one end of it shall turn to the North and the other to the South And if holding the Stone in your hand you turn his North point to the South extremity or end or contrarywise the Stone shall then draw Iron but contrarily if you turn the like part to the like as is aforesaid it shall fly from the Iron and drive it away Impossible Impossible Natural The reason is that the agent doth not onely indeavour to make the patient like it self but also in such a manner to unite it with himself that of them two be made one as may appear by this reason Take the same Magnes A D. of which A. signifieth the North point and D. the South Divide the Stone into two parts A B. and C. D put A B. to the Water as is said and by this means you shall see A. turn to the North and B. to the South For the breaking or dividing of the Stone as we said diminisheth not the Virtue thereof so that it be Homogenie that is all parts alike Take therefore A B. for the patient and C D. for the agent then whereas the agent in the best manner it may worketh to conserve the order of Nature â—t is manifest that D. cannot draw C the South For although they could by that means be joyned yet should not so be made one of them two the parts remaining in their Vertue For if A. should remain North then D. should be South which is certain to have the powers of the North. Neither contrariwise shall C. draw A. for both are Northly and so should B. be the North which first was South and D. in like manner For so should the order of Nature be inverted It remaineth therefore that A. shall naturally draw D. and B. shall draw C. for so every way shall remain of equall strength Some ignorant Men were of opinion that the Vertue of the Load-stone was not derived from Heaven but rather of the nature of the place where it is engendred saying that the Mines thereof are found in the North and that therefore ever one part of the stone extendeth towards the North. But they surely are ignorant that this stone is found in other places whereof it should as well follow that it should extend it self to other and divers parts as to the North which thing is false as is well known by common experience For it ever Moveth to the North in whatsoever place â—it be Neither is it to be believed that the North-Star of the Marriners is the Pole For as much as that Star is without the Meridian Line and but twice within one revolution of the Firmament But whereas the Marvelous Vertue of this Stone dependeth of Heaven who would believe that only two points thereof should so turn themselves and that rather every part of it should not incline to some like part in Heaven as may thus be proved Let the Stone be brought into a Spherical round forme as is said and the Poles being found let it be turned upon two pins or Turners instruments and there be pullyshed untill it be on every part of equall heaviness which you may well find by often proving For that part that falleth down is heaviest which done frame in
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
suit princeps manibus conficeret rem Nos sâ—boies scribarum emersiâ—ex aequere Nigro Consecratemus calumum Magnetis ad aras Thus Englished The Load-stone above all other Stones hath this strong property If sundry steels thereto or Needls ye apply Such force and motion thence they draw that they incline To turn them to the Bear which near the Pole doth shine Nay more as many steels as touch that Vertuous Stone In strange and wondrous sort conspiring all in one Together move themselves and scituate together As if one of those steels at Rome bestirred the other The self same way will stirre though they farre distant be And all through Natures force and secret Sympathie Well then if you of ought would fain advise your Friend That dwells far off to whom no Letter you can send A large smooth round Table make write down the Christ-Cross-Row In order on the Verge thereof and then bestow The Needle in the mid'st which toucht the Load that so What note soe're you sift it straight may turn unto Then frame another Orbe in all respects like this Describe the Edge and lay the steel thereon likewise The steel that from the self same Magness motion drew This Orbe send with thy Friend what time he bids adew But on the days agree first when you mean to prove If the steel stir and to what Letters it doth move This done if with thy Friend thou closely would'st advise Who in a Countrey of far distant from thee lies Take thou the Orbe and Steel which on the Orbe was set The Christ-cross on the edge thou seest in order writ What notes will frame thy words to them direct thy steel And it sometime to this sometimes to that note wheele Turning it round about so often till you find You have compounded all the meaning of your mind Thy Friend that dwells far off O strange doth plainly see The Steel to stir though it by no man stired be Runing now here now there He conscious of the Plot As the steel guides pursues and Reades from note to note Then gathering into words those notes he clearly sees What 's needful to be done the Needle Truchman is Now when the steel doth cease its motion if thy Friend Think it convenient answer back to send The same course he may take and with his Needle write Touching the several notes what so he list indite Would God Men would be pleased to put this course in Ure These Letters would arrive more speedily and sure Nor Rivers would them stop nor Thieves them intercept Princes with their own hands their business might effect We Scribes from Black Sea scaped at length with hearty Wills At the Altar of the Load would consecrate our Quills Of this devise how two absent Friends might conferâ—at a great distance Viginerius in his Annotations upon T. Livius speaketh somewhat in the 1316 Columne of â—his first Volumne as namely that a Letter might be Read through a stone Wall of three Foot thick by guiding and moving the Needle of a Compass over the Letters of an Alphabet written in the Circumference But the certainty of this conclusion I leave to the experiment of such as please to make tryal of it but to pursue our present design There is not any one errour that breedeth a greater confusion in Magnetical Knowledge then the mistaking of the right understanding oâ— the true North and South ends as well in Magnet themselves as also in Magnetical Bodies whosoeveâ— therefore will take a little pains to understand this well shall free himself from many intricate difficulties in thâ— argument which otherwise must needs befall him wherein some having Limed themselves have falleâ— into many errours every one still begetting anotheâ— worse than himself All those which Write beforâ— Doctor Gilbert did name that end of a Magnet whicâ— being placed in a Wooden Dish and set to swiâ— in Water would turn and settle it self as we have said towards the North the North end of the Magnet and the other the South end And even so did they oâ— all Dyal Needles Compasses and Magnetical Bodies But Doctor Gilbert not for any new fangled innovation or self conceit but upon good reason and firm demonstration avoucheth and proveth the contrary and clearly sheweth that the former vulgar assertion seriously defended tendeth to the overthrow of all Magnetical Phylosophy by undermining of as it were the whole frame thereof and yet in common speech the old Rule may hold Loquendum cum vulgo sentiendum cuâ— sapientibâ—â— For it would seem a strange speech to a Marriner to tell him that his Flower de Luce were become the South point of the Compass and yet this assertion is most true and certainly that it is the North end of every Magnet and Magnetical Body that being placed in a thin Wooden Dish in Water or any Magnetical Needle upon his Pin which seteth it self and pointeth to the South and it is the South end which pointeth to the North. For proof hereof take these words of North and South in whether of the two former significations you please and make tryal thereof in any two Magnets or any two Magnetical Bodies so placed that they may freely turn according to their natures and you shall always see a natural inclination of the contrary ends of the one to the contrary ends of the â—ther as of the South end of the one to the South end of the other and reciprocated of the South of the one â—o the North of the other but the ends of the one in the other will always fly from those of the like denomination as the North end of the one from the North end of the other and the South end of the one from the South end of the other For as much then as all Magnets themselve and all Magnetical Bodies being so placed as that they have their free motion compose themselves Magnetically towards the Poles of the Earth it must needs be that it is the true natural South end of the Magnet or Magnetical Needle that pointeth towards the North of the Earth And it is the true natural North end of the Magnet or Magnetical Needle that ponteth towards the South of the Earth because the contrary ends do affect one another and each of them do naturally fly the one end of the one from the end of the other which is of like denomination unto it self for Example in this following Diagram of the whole Magnet E A. is supposed to note the true natural North end thereof and B. the South end This Magnet being placed in a Wooden Dish swiming in Water freely must and will of Magnetical necessity with his true North end A. settle himself so that A. must point towards the South of the Earth and the South end B. towards the North of the Earth because all Magnets and Magnetical Bodies do naturally affect the one the contrary end of the other and do avoid and fly from their ends of
denomination Now for a further consideration of these properties suppose that you will cut a piece of this Magnet Meridionally viz. C D. manifest experience will shew that C. which did in nature participate with A. in the intire Magnet E. as being both of the true North part thereof now being seperate will not abide it In like manner D. of the other end of the little one will not abide B. of the great one with whom being intire in nature he did participate as being both the Southerly parts of thr entire Magnet E and that because the ends of like denomination of any two Magnets do naturrlly fly the one from the other The stone being brought to his perfect form you must have a mould made of Iron of the same proportion in every respect and equal in all his dimensions then setting your stone aside let your Work-man frame and fassion his caps and sit them upon his mould as if it were the stone thus shall you be sure to preserve your Magnets from many dangers very incident to rude handling and having so done you may set them on the stone it self amending any small faults without indangering the stone either with bruisings or knocks for the thickness and largness of the caps there can be no general rule prescribed but it must be left to the tryal and ingenious discretion and dexterity of the Workman as also for the handsome fastening either by Soadering or Reveting of them with Latin plates to the caps to keep them in their places fast and firm and steady according as you see in the Ticture of a stone armed with single caps Now therefore in this position both ends of the Magnet being applyed unto the two ends of the Iron these two contrary forces strive in this piece of Iron the North to repell the South and the South the North so that each force is driven nearer his own end and becometh there so much the stronger then otherwise it would be For proof whereof take a little narrow square piece of Iron of the length of the capped stone and joyn it in the midst with Copper after this manner A. iâ— supposed to be a â—â—ng square on a square like piece of Iron in length fitting the two double caps of a Load-stone B. a long square piece the ends Iron the middle Copper and D. least of all If you apply the Load-stone unto A he will hold A. very strongly but if you put any of the other three pieces under A that it may touch any of them he will not by any means lift it up If you apply the Load-stone unto B he will take it up very weakly and C. somewhat more strongly but D. strongest of all these three yet not comparable to the strength wherewith he taketh up A. Aagain although the Load-stone take up B. but weakly yet if you place B. upon A he will take them up both very strongly yea more place B. upon C the two upon D all three upon A apply the Load-stone upon B being the uppermost and he will lift them all up very easily The cause thereof is when a Load-stone with his double cap is placed upon A the force of both ends striving in that piece of Iron paralellwise unto the Axis of the stone the North and South forces are driven more closely unto their proper ends But B. because of the immediate Copper there cannot be no such close driving of his forces unto their proper ends as was in A and therefore the Load-stone lifteth up B. but only as if his two ends were two little loose pieces of Iron hanging in the Air and the intermediate Copper a burthen upon them But by placing B. upon A A. in the manner as it were of a Bridge joyneth the two ends together in their former combats and the two ends of B. forasmuch as they are but as it were two loose pieces of Iron hanging in the Air the two forces of the Load-stone North and South distinctly and severally pass thorough them downwards into A which iâ— could not do if it had been one intire piece of Iron and so all those four pieces being placed one upon another so that A. be undermost whether directly or side-ways the Load-stone will easily lift them all up and not otherwise When a Load-stone lifteth up Iron at one end only the virtue of a stone is infused into the whole body downward of that Iron if it be not very long But when by means of the double caps both ends do lift Iron joyntly together he infuseth very small force downwards into the body of the Iron that it lifteth up for the forces of both ends are so striving in the Collateral Line of the Iron paralell to the Axis of the stone that whereas a good Magnet lifting up at one end will entend his virtue downwards twelve or fourteen Inches in applying both ends unto the Iron by the means of the double caps he will not extend his force downwards the distance of one Inch nor with any strength the distance of half an Inch as in this former Example Pliny in his natural History writeth that Dinocrates that Famous Architect Builder of Alexandria at Ptolomies command began to vault a Temple with Magnets that there might seem to hang in the Air the Image of his Sister Arsinoe made of Iron for that purpose but both Dinocrates and Ptolomie dying in the mean space that enterprise ceased Neither indeed if the both had lived could it ever have come to pass by that means by reason of two impossibilities the one is that by the force of the Load-stones nothing can so hang in the Air but that it either must touch the stone it self or some other intermediate substance between it and the stone that bareth it from coming to the stone it self For Example lay two or three Needles upon a smooth Table put a Silver or Pewter Plate upon them and upon that Plate a Load-stone then lift up the Plate aloft with the Load-stone lying still upon it and you shall see the Needles hanging indeed in the Air endlong and if you move the stone about the Plate following still underneath but evermore touching the Plate which is the intermediate body which keepeth them from coming to touch the stone which otherwise by their natural inclination very speedily they would do But as for the Image of Arsinoe how had it been possible for it to have toucht at once mediately or immediately so great a number of Load-stones whereof the pretended Vault must needs have consisted the other is that such a multitude of Magnets would nothing but confound the one the others forces so that one of them alone being solitary and severed from his company might shew more force than all the insociable society could do each one hindering the efficacie of the other Much like a Team of many Horses where every one drawing his several way might soon with disordered stretching tire himself and his fellows but never
move the Load one jote from the place Insomuch as one and possibly the worst would do more good alone where he might orderly and freely use his own strength then he and all the many of them could do being joyned together in vicinitie of bodies but extreamly distracted through contrarity of courses The only way to perform such a design if it were worth â—he doing would be to prepare one mighty great Load-stone of excellent goodness which having his due proportion after an extended Ovall form should be fitted with double caps and so placed in the Roof of a Building that his Axis be paralell to the Horizon in this manner out of all doubt a fair large Image might be held up very strongly by such a Magnet let the stuff or substance thereof be whatsoever howbeit the lighter the better so that there be fastened to the uppermost part of the Image a small piece of Iron according prepared and placed for the two prominent ends of the double caps of the stone to lay hold thereon But enough hereof In the caping of the Magnets this general rule is to be observed that they ought to be made of the finest and softest Iron and not of Steel the weight also which the Magnet taketh up should be of the like Iron and not of Steel as aforesaid for although Steel at the least retaineth Ten times as much virtue as Iron when it is once seperated from the stone can doe yet as long as there is any contignity between the stone and them he holdeth Iron more stronger than Steel Both which differences in either of them by manifest experience are certain and seem to proceed from notable fastness and closeness in the Steel above the Iron by means whereof the Magnetical Virtue doth longer and more forcibly continue in that than this even as fire more mightily possesseth and for a greater space abideth in stone or any such firm or solid matter then in Wood or Straw or the like thin and hollow substance and therefore those Compass makers that make the Wiers of their Flies for Sailing Compasses of meer Iron ought not by any means to be suffered for to gain Two-pence in a Compas and scarcely that they intollerably abuse those that Travel by Sea to their great danger and mischief To cement and piece Load-stones for your Simmon doe thus take the fine powder of Load-stone half so much powder of New-brick made very small and subtill one part of Burgundy-pitch half so much of Rossen a small portion of unwrought Wax mingle all these together very well upon a soft Fire and make the whole Mass in little Roules Now when you will cement a stone do thus heat the two pieces of the stone very hot and likewise the Simmon then strake the places as you will soder over with the Simmon very thinly and joyn them somewhat hard together letting them so stand untill they be cold and you shall have it fully as strong as if it were an intire stone it self and not to be severed by great heat of Fire In piecing of the Load-stones there must be great care taken to the nature of the Load-stone in general and also to those particular pieces which you would joyn together The Load-stone in general as it is shewed before that his force issueth as it were from a center in the middle of the stone to all the superficies whereof universally but most strongly unto the Poles from the middle one way the stone is all of a Northly nature and all of it Southly the other way For Example In Load-stones there is a part truly said to be divided from the whole when the points of that part or ends or Poles and so by necessary consequence the Axis and Aequator in which the universal frame of Magnetical power consisteth have a position diverse from the Poles or points of the World For this cause in the last example the one half A B. being supposed to swarve from the other half B A. at either end must needs presently be divided from it and now cannot be pars integri but is of necessity totum integrali a several and absolute Magnet of it self and so by an essential property common to all Magnets coveteth with his point A. the contrary B. of that which is under it Wherefore like as exact agreement is between two Mathematical Figures when being applyed together the extreams of the one do precisely fall upon the extreams of the other each upon his correspondent extream and it is made one therewith even such is the perfect composition or setting together the parts of a Magnetical Body and namely of those two equal parts before exemplifyed you must so joyn one upon another that the two extreams or ends be always of the same nature Northly or Southly in both parts and that by the due application of the parts the two Northly ends being united and become one as also the two Southly after the same manner But if these parts being of equal length be joyned longwise the North of the one unto the South of the other those two ends that were being now no ends but the just middle of one Magnet have lost their properties which they had when they were ends For those properties by this Union are abolished but their other ends still reserve their former and stronger virtues of North and South and so according to Magnetical nature one Magnet shall have but two Poles the North and the South Again if you will piece two Load-stones together in thickness the one of them being longer than the other then you must either cut the longer that it may be fit in length unto the shorter or else piece the shorter in such a manner as is before described that he be equal in length to the longer and whatsoever disorderly parts perhaps shall be in any of them they may even after they are cemented very well be ground away Also if there be holes or dents with little pieces of Load-stones cemented their points being observed they may be filled up without any manner of damage or deformity no more then if there had not been any such at all And after this Method you may with labour and industry of many Magnets make one huge and of what form you please And although the Magnets of this body Magnetically compact as I have here shewed were never so many in number yet the whole will have but two principal points the one the North the other the South even as if it were one natural Load-stone and all of them will contribute their forces unto these two points so that if there were twenty of them being after this order cemented together into one body the whole would have but two points but if you will place them in a Vault according to a Masons Trade they will have 40 points twenty North and as many South and will work the like effect in drawing Iron as to use the former gross similitude if
a Teeme of Horses were set in their Traces contrary the one to the other the one to pull one way and the other anorher As for the Turks Mahomet hanging in the Air with his Iron Chest it is a most gross untruth and utterly impossible it is for any thing to hang so in the Air by any Magnetical power but that either it must touch the stone it self or else as we have said some intermediate hoby that hindereth it from coming to the stone or else some stay below to keep it from ascending as some small Wyer that can scarcely be seen or perceived Concerning the Magnetical force of the whole body of the Earth I have selected these experiments to prove it Take any piece of solid Earth that hath some toughness â—o hold together and will abide the fire as any sort of Clay or Brick which sometimes was Clay fashion it in such manner that it be uniformly extended towards both ends the Orall or Long Figure is fittest for our purpose put it into a Fire of Charcoales increasing the heat by little and little and at the length with often blowing make it as throughly red hot as you can let it remain so for the space of half an hour or more that thereby all the superfluous moisture may be consumed and adverse qualities seperated from it then take it forth and let it coole it self being first set North and South with either end answerable to the variation of the place not paralell to the Horizon but elevated answerable to the Latitude as near as you can Certain it is that this piece of Earth thus ordered will sensibly shew you that it hath true Magnetical Virtue But here before I proceed any farther I must deliver unto you a necessary observation There are two sorts of Attractions as they are commonly called the one Magnetical the other Electrical The Magnetical hath always a special respect to the North and South points as we have often said of the Magnet or Magnetical Body The Electrical Body hath no manner of respect to any one point of the Electrical Body more than another and by this difference these two kinds of Attractions are easily discerned as also by this look what end of the Magnetical Needle the one end of the Magnet doth draw the other will chase away but the Electrical Body draweth alike at all ends And Thirdly after this manner lap this Electrical Body in a Paper and it will draw nothing to it at all but interposition of Brass or a stone Wall within the Orbe of the Magnets virtue doth nothing weaken the same or hinder his effect towards his peculiar object Notwithstanding to speak properly Attraction appertaineth only to Electrical Bodies because the whole Attractive virtue is only in the Electrical Body it self and nothing as in the thing that is attracted The Attraction commonly so called of the Load-stone is rightly to be termed Concursion Confluence or Coition because it is the running or vigorous meeting together of two Magnetical Bodies having a mutual Inclination the one with the other or by any other name bearing the like sense For the true knowledge thereof being but lately as a stranger arrived amongst us for common use Quem penes arbitrium est et jus et Norma Loquendi hath as yet scant suited it with a convenient Name to express this property so that Magnetical conclusion is never but between two Bodies such as both of them are Magnetical as of one Load-stone with another or of a Load-stone with Iron or Steel or Iron Oare if it be prepared or between two pieces of Iron or Steel thac are Revived with a Load-stone for indeed the Load-stone can but revive and multiply Magnetical force in a Body that naturally hath it in some measure before but cannot infuse it into any thing that before is utterly void of it as of Mettalls in Iron and Steel and not in Gold Silver Brass c. Electrum in this Argument is named that which is either Amber in substance or at least of the quality and that Amber being â—ubed hath an attraction to take up Moats Feathers Straws and other small things the which property is also in â—eate Brimstone Hard-wax if it be smooth and in infinite other things both natural and compound all which because of that quality in this Argument are termed Electrical Bodies and their taking up of things is called Electrical Attraction having only a slender resemblance â—ut no truth of the Magnetical Quality But that above mentioned piece of Earth prepared in such a manner as is before prescribed will by Magnetical Concursion shew it self to be a true Magnetical Body For the one end of the Magnetical Needle will covet towards the one of the prepared Mass and flye from the other And contrarywise also though it will do both but weakly not with power comparable to a natural Load-stone yet as truly as that That end which cooled towards the South will draw the true North end of the Needle and that end which cooled towards the North will draw the true South end of the Needle If so be that as yet you will have another in fallible Argument do thus mark what end draweth the North end of the Needle afterwards put the new made Magnet into the fire again and when it hath been glowing for the space of half a quarter of an hour take it out and cool it being placed with that marked towards the North most assuredly that end now will draw the South end of the Needle and the North end of the Needle will shun it which before approached unto it the reason hereof is because the first having abolished all the former Magnetical quality of that Mass wherewith it was in a contrary position affected in the former cooling now leaving it apt and fit to receive any new Impression which presently it taketh again either regularly if in the cooling it be placed with the ends to the North and South or if it be placed otherwise confusedly by the Magnetical force and virtue of the whole body of the Earth by regular and confused this is the meaning Take any lump of Earth or any Brick-bat ordered in this manner certain it is that this â—ump of Earth or Brick-bat hath some Magnetical virtue therein yet so feeble and weak that our sence cannot discern it because of the unfitness of the form and the confused dispersion of that weak force through the whole body thereof Then suppose you will bring either of these into an extended Ovall form which is apt as before I have said for any body Magnetical to shew his force yet this will help it nothing at all of it self as you may easily make experience in every Load-stone For if you take a Load-stone of a confused form it is not enough to bring it into a convenient Ovall except with diligence you reserve the points of the North and South in the two ends thereof for if you leave the points
to draw towards an end of this matter albeit that the Magnetical virtue be most eminent in the Magnet as in the precise and perfect subject thereof yet it is the self same quality in a meaner degree evidently to be perceived in every piece of Earth prepared and ordered as is aforesaid yea although it be not cooled with his ends North and South that it may take its Magnetical force from the virtue of the Earth for if you cool it with his ends but East and West and set two Load-stones in the cooling the one at one end and the other at the other end it will receive a sensible and apparant Magnetical Virtue according to those points of the Load-stone that were applyed unto it namely that end which was next to the South point of the Load-stone will have a North property and that end that was next the North point will have a South property yea if you set the North part of two Load-stones to each end both ends of this new made Magnets will have a South property and contrariwise if you apply the South ends of two Magnets both his ends will have a North property and those properties before mentioned will shew themselves Magnetical because whether end of this new Magnet draweth any one end of a Magnetical Needle the same will cause away the other which is proper only to Magnets and Magnetical Bodies After the like sort only by application of two strong Load-stones by the force of twenty four hours you may alter the points of any base Load-stone which you would and make them both North and South as you please so that the Load-stone that you would alter be but base in quality and not great in substance and that the other be of a reasonable bigness and good strength And this virtue by such an application of two Load-stones I have often found effectual in new Brick lately taken from the Kill without any farther putting into the fire at all and although it be against the nature of the Load-stone to have both his ends naturally of one virtue that is to say both of them of a North property or both of them of a South property yet here is to be understood that it is the forcible violence of the strong ones being applyed joyntly to each end of the weak that do chase the contrary property of the weak one into the middle thereof and therefore if you divide this weak one in the middle then both those ends which being joyned together in the middle where no Load-stone can shew any virtue being now disjoynted and become both ends will presently shew a contrary property according to the Magnetical Nature unto the other two ends The form of the stone is Represented in this following Figure The Form of the Stone I must have on the inner side certain little Nailes and Denticles and small Teeth of Iron of one equal weight to be fastened on the Border or Magnet so that the one be no farther distant from the other then is the thickness of a Bean. The said Wheel also must be in all parts of equal weight then fasten the Axletree in the middle upon the which the Wheel may turn the Axletree remaining altogether immoveable To the which Axletree again shall be joyned a Pin of Silver fastened to the same and placed between the two cases in the highest part whereon place the Load-stone Being thus prepared let it be first brought to a round form then as is said let the Poles be found then the Poles untouched the two contrary sides being between the two Poles must be fyled and polished and the stone brought in a manner to the form of an Egg and somewhat narrower on those two sides least the lower part thereof should possess the inferiour place that it may touch the Walls of the case like a little Wheel The Sea-mans Director as well in distress of Weather as also at his leasure times of Recreation how to make a right use of the Magnetical Needle how to manage the Sayling Compass and the rest of the Instruments of chiefest concernment in the Art of Navigation HAving already discoursed of the virtues of the Load-stone as we are very unwilling for to divide such dear friends we next shall Treat of the Magnetical Needle The variation of the Magnetical Needle being aptly fitted and placed upon his pin is nothing else but the swarving of the pointing of the same in the Horizon from the Meridian line there the portion of the Horizon intercepted between the true Meridian line and this pointing sheweth of what quantity the variation is and giveth it his name to wit which way it lyeth either Easterly or Westerly and it is observed by either end of the Needle as you please In times past men observed only by the North end of the Needle because they understood not that the Load-stone hath a South virtue as well as a North and therefore did touch their Needles and Wyars of their Compasses always for the North only leaving those ends of the Wyars bare that they might be refreshed with a new touch at any time afterwards but the other ends they covered not knowing that they were also apt to receive as forcible a virtue from the Load-stone for the South as the other for the North. For the right understanding of the variation which is necessary dependants we must use the means of two circles the one of them I will call the Magnetical Almicanter the other is already known by the name of the Magnetical Meridian This Magnetical Almicanter is a circle parallel unto the Horizon whose center is the Vertical point and is described by the distance between the Vertical point and the nearer Pole of the Earth the Magnetical respective pole or which is all one the Pole of the Magnetical Meridian is a point in the Magnetical Almicanter as the variation of that place containeth in the Horizon but always it is the contrary part of the true Meridian that is if the variation of the South part of the Needle be Easterly the respective Pole is Westerly but if you observe with the North end of the Needle the respective Pole and the variation are both one way in all our Northern Climates If the variation of the South point of the Needle be Westerly then is the respective pole so many degrees in the said Almicanter Easterly and therefore always of the same height with the true Pole above the Horizon For since all great circles of the Globe do necessarily cut one another in two points into two equal parts these two therefore must even do so in the Zenith and Nadir by the very definition so that these two points the Zenith and Nadir are always alike common to them both as well unto the true as unto the Magnetical Meridian Where-hence it followeth necessarily that always the one half of the Magnetical Meridian is on the East side and the other on the West side of the true
of Lattin or Copper and not of Steel or Iron as some suppose for they are very subject to rust and the Steel especially by long use will wear a little hole in the top of the Capital and â—y that means the Compass becometh dull and they hardly if ever will find the reason of it for the hole will be very small and entring a very little way in and yet disturbeth all Moreover in any wise there must be always an especial diligent Care had of fitness between the Capital and the Pin otherwise all things appertaining to the Compass are nothing worth This Pin must be very firmly fixed in the just Center of the Box and the bottom marked that whensoever you take it off to sharpen the Pin which use will make blunt you may set him in the same place again As I have said that in a Magnet it self the Vertue is in the whole body and sheweth it self most forcible in its Poles even so likewise our Compass Needle being a Magnetical body sheweth his force in his ends which are his Poles although that force doth proceed out of the whole body of the Needle which I have now thought good to make apparent by an evident Demonstration I caused my Workman to make a Needle of a Loop Fashion eight Inches long or Oval Form in all respects fitted to be set to a Flie saving that there was but one Inch or a little more at each end of the Steel all the intermediate part between the two ends being of Brass These two ends I did touch with the North and South ends of a very good Magnet and whereas in a true Magnetical Needle I should have had but two points the one North and the other South this Mongrel yielded me six the two ends adjoyning to the brass of contrary natures unto the sharp Points and would no more do the Office of a Magnetical Needle then a wooden stick because the Vertue was not in the whole and so communicated unto the two ends but each end was a Total of himself being separated and as it were divorced the one from all communication with the other by that intermediate brass the which being taken away and the two Forks joined together for that length presently he became one perfect true Magnetical Needle and the Vertue of those four confused Points which ere while was lost in the Forks will presently be found in the two sharp ends and now in his natural Seats Both these ends of Steel were fastened to the Brass and then that Needle had no Magnetical Motion but being taken off and joyned together they presently without any further touching of them became a true Magnetical Needle To conclude this discourse of the Compass of the Needle the needle that is still working upon his Pin continually will keep his force the better then that which otherwise laid up although there be no doubt of the other for a mans whole Age or longer if it be of good Mettal and kept from open Air and Rust but especially of any Load-stone There is no better way of keeping from rust then by varnishing him although it be but with a drop or two of Linsed-Oyl alone the Needle that is continually upon his Pin is still strengthened by the Magnetical power of the Earth setting himself always towards the Poles thereof which the other cannot do and needeth only to have his pin sharpened only now and then the which of all the faults incident to the compass is most easily and safely amended And yet if it be not very well looked unto it disturbeth all the operation of the Compass more then any other And divers wrong themselves in being too busie in often touching their Compasâ—es the fault being in this which no touching can amend I have thought good to conclude this short Treatise with a little additament to the ordinary Sailing Compass fitting him thereby to be answerable to the several here prefixed as also with a comparison of the several uses of the Horizontical and Inclinatory 〈◊〉 let the glass of the inner box of the Compass be of good thickness and strength but yet clear and even theâ—e that come from Venice for Looking lasâ—es before the Soile be set on are the best if any Man may have them large enough Let this Glass be very well fitted unto the box and simmoned underneath upon the should'ring of that beareth up the Glass with a mixture of Wax Turpentine Sallet-Oyl and Rosin mingled together or with any other simmon as you shall think good above upon the Glass â—et there be a Ring of thin Pastboard of the breadth of the Should'ring underneath in like manner simmoned on then must you have a circle of Lattin about the breadth of the Pastboard Ring of convenient thickness for strength which must be divided into degrees this circle must have a plate of Lattin of half an Inch-broad or broader according to the largness of the circle for strength that must cross over the middest of the circle cut out of the same place with the circle or else soadered with Silver soader this must have a line all along the middest of it and a little loop at each end cut through the two ends of the loops being precisely in that line Lastly you must have a moveable Ruler with two long folding sights of about the Semidiameter of the circle in the breadth above half an Inch the one of them must have a flit through the length thereof of about a quarter of an Inch broad as you shall think convenient and two little holes the one in the top and the other in the bottom just in the middle of it to fasten a string having a very little bead to slide up and down upon it And this sight must be of thicker stuff then the other for otherwise because of that which is cut out it would be overpoised by the other and so the box would swarve towards the other and the sights must each of them have a little notch in the middest of the top of them this Ruler must be fastened but yet so that he may turn about in the middle of the cross plate most precisely in the center of the circle his ends cut that he may shew the Fiducial Line in the divisions of the circle the other sight needeth to be but a plain plate having a line in the middle from the top to the bottom being the very same in substance with that which we call the compass of variation although in all things easier performed with this then with that The Compass being thus fitted place the circular Needle upon his pin alone without any flie For being disburdened of the Card he will shew his virtue the more strongly and being of the right form he will ballance himself sufficiently Place the circle upon the Glass and Past-board in such a manner that you may turn the circle round about very close and even within the brim of the box When you will
watery Camp Whereby a Ship that stormy Heavens have whorl'd Near in one Night into another World Knows where she is and in the Card descries What degrees thence the Equinoctial lyes It may well be then that Flavius the Metuitan was the first Inventor of guiding of a Ship by turning the Needle to the North But some German afterwards added to the Compass the 32 Points of the Wind in his own Language whence other Nations have since borrowed it But surely great pitty it is that the Author of such an Invention is not both more certainly known and more honourably esteemed He is better in my judgment to be inrolled and ranked amongst the great Benefactors of the World then many who for their supposed Merits of Mankind were Deifyed amongst the Heathens So that it may be said of the Inventor Exegit Monumentum aere pereunius Regalique sicu Pyramidulum aeltius Questionless those of former Ages were for want of this knowledge so ignorant of the Art of Navigation that they ingraved non Vltra on Herâ—les Pillars that the Nations about Poâ—tus thought no Sea in the World like their own and doubted whether there were any other Sea but that only whereof it came that Pontus was a word used for the Sea in general that the Aegyptians held otherwise a witty people used to coasâ— the shores of the Red Sea upon Raffs devised by King Erythrus And in the time of the Romans the Brittains our Ancestours had a kind of a Boat with which they crost the Seas made all of twigs and covered with Leather of which Lucan the Poet. Primam cuna salix madefacto nimine parvam Texitur in puppim casoque iduta ivenco Vectoris patiens tumidam superenatat aumem Sic Venetus stagnante pado fuscque Brittanus Navigat Ocâ—â—no The moistned Osyer of the hoatie Willow Is Woven first into a little Boat Then cloathed with Bullocks hide upon the Billow Of a proud River Lightly doth it Float Under the Waterman So on the Lakes of overswelling Poe Sailes the Venetian and the Britains so On the outspread Ocean And to the like purpose is that of Festus Aviennus Navigia junct iâ— semper 〈◊〉 â—ellibus Curioque vastum saepe percurrant salum Of stiched hides they all their Vessels had And oft through Sea in Leather Voyage made But that which is more observable is that the Jews were so unskilful in this Art as they commonly called the Mediteranean Sea the great Sea not being in those times as it seems much acquainted with the Ocean And though the Phenicians and Carthaginians the Tyrians and the Sydonians are much renowned in Histories for great Navigators yet it is thought by the Learned that those Voyages they performed was only by coasting and not by crossing the Sea Haec aestas quod fâ—ta negarunt Antiquis totum pâ—â—tuit sulcate carinis Id Pelugi immensam quod circuit Amphitrite This age what fates to former times deni'd Through the Vast Ocean now in Ships do ride Saith Fracastorius and Acosta Equidem Navigationem altissimo Oceano commissam neque apud Veteres Lego neque apud illis aliter Oceanum Navigntum puto quam a nostris Mediterraneum That the Anâ—ients adventured themselves into the Main Ocean neither do I read it in any of their Waters nor do I believe that they otherwise sailed over the Ocean then we do now over the Meditterranean Sea and it should seem they undertook not their longest Voyages without Oares which the Scripture implies in that undertaken by Jonas where the Marriners upon the rising of a Violent Tempest were constrained to use their Oars The perfection then of this Art seems by God's Providence to have been reserved to these later times of which Pearo de Medona and Baptista Ramusio have given excellent Precepts But the Art it self hath been happily practised by the Portugals the Spaniards the Hollandâ—rs and our own Nation whose Voyages and Discoveries Master Hacklait hath collected and reported in several Volumes inlarged and perfected by Mr Purchas and it might be wished as well for the Honour of the English Name as the benefit that might thereby redound to other Nations that his Collections and Relations had been Written in Lattin or that some Learned Pen would be pleased to turn them into that Language Among many others in this kind the Noble spirited Drake may not be forgotten who God being his Guide Wit Skill Valour and Fortune his Attendants was next after Magellanus that Sailed about the World Whereupon one writ these Verses unto him Drake Peregrati novit quem terminus Orbis Quemque semel Mundi vid it uterque Polus Si tacean homines facient Te sidera notum Sol nescit commitis imemor esse sui Sir Drake whom well the Worlds end knew Which thou didst compass round And whom both Poles of Heaven once saw Which North and South do bound The Stars above will make thee known If men here silent were The Sun himself cannot forget His Fellow Traveller P. Columbus being in the company of some braging prating fellows amongst other of their fooleries they fell upon him and said he had done nothing but they could do After he had patiently heard them he called for an Egg and asked which of them could make it stand upon one of the ends they said they could not do it why then says he I can and breaking one of the ends he fixt it Why said they this we can do yes verily says he without doubt this is but an easie enterprise yet this you could not do till you have seen me first do it For the better breeding continuance and increase of Pilots amongst us it would doubtless be a good and a profitable work according to Mr. Huckluit's honest Motion in his Epistle Dedicatory to the Lord Admiral if any Man who hath the means had likewise the mind to give allowance for the reading of a Lecture oâ— Navigation in London in imitation of the late Emperour Charles the Fifth who wisely considering the rawness of the Sea-men and the manifold Shipwracks which they sustained in passing betwixt Spain and the West Indies established not only a Pilot Major for the examination of such as were to takes charge of Ships in that Voyage but also founded a Lecture for the Art of Navigation which to this day is read at the Construction-house at Sevil the readers of which Lecture have not only carefully taught and instructed the Spanish Marriners by word of mouth but have also published several exact and worthy Treatises concerning Marine causes for the direction and incouragement of Posterity and namely these three Alonzo de Chanez Hieronimo de Chanez and Roderigo Zamerum and to this purpose it was a commendable work of Mr. Gelibrand Reader of Gresham-Colledge for the improvement and advancement of the Art of Navigation published a most excelent Book of Logarithmes But to return to the Sobject we have now in hand concerning the nature powerfulness and strange proâ—erties
if there be great virtue in Stones Woods and Herbs It hath also been proved that the Ships Compact with Iron Nailes Sayling by the Sea of Aethiope and by a Tempest driven to Land to certain Capes or Lands ends have by these stonas either been drawn to the bottom of the Sea or else the Nailes being drawn out by the Virtue of the stone the Ship hath falen in a thousand pieces And therefore the discreet and wary Cantabrians expert Mariners Sayling by the Aethiopian Sea frame their Ships with Pins and Hoops of wood to prevent the danger that might chance on the same occasion This stone is known by colour virtue weight and equality the best colour is said to be like pure Iron shining mixed with Indian or Heavenly colour and is in a manner like Iron Polished This stone is also often times found in Norway and Elua and in certain Regions of the North and is brought from thence to certain Regions in Normandy and Flanders The experience of the virtue of the stone is easie for it attracteth to it a great weight of Iron It is judged to be strong and the heavier also the better By equality it is judged if it be alike in one substance and colour but if it be unequal with chapes as we shall hereafter express together with hollow places indented having red spots here and there it is unapt not so fit for the Art of Navigation or of continual Motion It representeth the similitude of Heaven for like as in Heaven there are two points immoveable ending in the Axle-tree of the Sphere upon which the whole Frame of Heaven is turned as may be experienced by the Art that Christal and other stones are Polished even so the Load-stone reduced into a Globious or round Form laying thereon a Needle or any other like Iron then which way soever the Needle turneth and resteth thereby is shewed the place of the Poles and that this may be done more certainly it must be often times attempted and the Line shewed by the Needle must be observed for such Lines shall cut the one the other in two Points as the Meridian Circles joyn together the Poles of the World but of this also more shall hereafter he said This shall for the present be only instanced That if the round stone as is said be found in the place which often times draws Iron if then the point doe exactly appear part of the broken Needle must be laid upon the sinne and be so often by little and little transposed untill the Style or â—in be Perpendicler or Plummet do directly fall upon the stone for there on the contrary part by like manner shall be found the other Pole A. shall be the true point and B. the false Load-stones let them be of what parts soever of the World have the self same general directive property I mean of shewing the North and South and also the self same Points respective declining or dipping under the Horizon They do likewise agree in their variations and each one will draw Iron and likewise one another Every Load-stone of what form soever it be hath either actually or potentially two points the one Northern the other Southern Actually if either by casualty if it so fall out or by â—ndustry the stone be fashioned that those two oppoâ—â—e points be eminent or perspicious therein Potentiâ—lly if that either the stone be flat and but thin in the dimension of the North and South though broad otherwise for so shall the virtue of the stone be dispersed to the extream parts thereof in the Edges round about or if fit have two opposite points in any concavity then will the stone shew in the eminent Border or Edge of that concavity only a confused dull force and in the concavity very little or nothing at all That stone is also well proportioned for touching which resembleth an Oval form and hath his due points in his ends and is void of any bunch or concavity for the general form of a stone being good every concavity is a diminishing of his force and every bunch is a superfluous Burthen Insomuch that my self have had experience of a stone that of substance was very good and of weight was three and twenty ounces but of disordered form it therefore took away twelve ounces from him and yet diminished not one jote of his force And this I did in a stone that was all of like force but if it be one that is intermixed of divers substances as many such there are and those easily discovered by their colour you may sometimes take away three quarters or more of his substance without diminishing any thing at all of his virtue we have already said the Iron colour is best very black or white seldom proves good gray indifferent the moâ—â— white is in any stone so much the â—â—rse Thâ—â—e are certain that are of an Iron colour mâ—â—glâ—◠〈…〉 of which 〈◊〉 are good and some bu◠〈…〉 〈◊〉 wâ—y you may prove whether a Magnet be goâ—â—◠〈◊〉 the 〈◊〉 is by 〈◊〉 aâ— Iron with the bare stâ—â—e that other by giving more or less virtue to a Knife on any thing to lift Iron the third is if it will with good strength move a Magnetical Needle a pretty good distance off and readily alter the ends of the Needle without touching them making the North South and the South North the two latter do never fail but the first doth divers times And very certain it is that whatsoever stone doth most stronly impart his force to a Knife or move a Needle with quickness the power and lifting up of Iron is such a one will mightily be increased with a Cap. For this is generally the nature of all Magnets that if there be two of different quantities and of equal strength in lifting up Iron the greater will give the stronger touch and move a Magnetical Needle farther off although the lesser will take as much Iron or somthing more than the greater And again suppose there be a Load-stone of a pound weight that being fitly armed will take up four pounds of Iron and not above if you divide him into very small pieces you shall find of them being orderly used that will lift up twenty times his own weight and a great deale more if they be very small as of three or four Grains weight and yet where the great one will give a touch unto a Knife for to take up four ounces of Iron and will move a Magnetical Needle three Foot off this little one will not give a touch to a Knife to take up a Needle nor move a Magnetical Needle four Inches off that as a Magnet is diminished in substance I mean a Magnet of a regular for it so doth he loose in his virtue and touching and increaseth in his small 〈◊〉 for lifting â—p Iron â—hereby it is manifest that these two properties 〈…〉 joyntly together in the 〈…〉 â—nd here hence it is that many 〈…〉 ally set in
or file somewhat from that end that hangeth down or else add a piece of Wax or some other thing to the other end of the Needle to counterpose it and make it stand equidistant as it did at the first setting on and this is a thing very certain that is the Northerly descent of the Needle will be more or less in all places of Northerly Latitude in the greater Latitude the more and in the lesser Latitude the lesser But if any Traveller carry this Needle beyond the Aequatour in the like Latitude Southerly that end which is downwards in the Northerly will rise Southerly and the other sink down even as much and the nearer you Travel towards either pole the more that end which pointeth towards the pole will tend downwards this is most certain in every Dyal Needle but a great deal more appeareth in a long one then in a short one we cannot find that the property of direction by the Magnetical Needle hath been unlargly practiced for Sailing above 300 years And as for the property of declination under the Horizon thereby to shew the Latitude by the Instrument thereunto belonging it is as yet a very new come Guest into the World born and bred with us in England and except it had been in exceeding few mens hands yet much used much less come unto his perfection But this is not to be marvailed at because it is not above 60 years old neither is it to be wondered at if any Critical Fellows do contemn and deride it forasmuch at either their want of knowledge or of patience will not give them leave truly to consider of it But what Navigatour or rather Nugatour whatsoever contemneth it shall be sure to repent if ever he comes to his right wits to consider what it is that he hath contemned And although the Needles for direction and declination do differ much in their shapes each from the other yet the properties are both one and the same For the Needles for direction do decline as aforesaid as far as the unfitness of their form and place will permit them and the declining Needle will not work but only in his Magnetical Meridian which himself will find out if you turn the Instrument about untill the Needle shew his least declination under the Horizon and there do play up and down and stop in the end of the same place again But if you would have a Needle fitted to shew both his properties do thus cause a Needle to be made about six Inches long even and smooth saving that he must be a little bigger in the middle then instead of an Axis which declinatory Needles have let him have a small hole drilled precisely in the middest and this hole being very small let it be somewhat wider outwards on each side then in the middest which our Workmen call Sinkboared where it must be left very sharp even almost as the edge of a Knife put through this hole a small Virginal Lattin Wyer and fit the Needle so that it hang precisely even upon this Wyer instead of an Axletree then touch him with the Loadstone and you shall presently see the end that should point towards the North decline or bend down to his due point of declination if it be placed in the Magnetical Meridian and set a little piece of Wax or any other thing upon the contrary part for a counterpoise in that the Needle may stand parallel with the Horizon then if you stand at right angles with that Virginal Wyer it is certainly in the Magnetical Meridian so that hanging in this counterpose if you turn about the Wyer untill the Needle do make right Angles with it then doth the Needle by his directive virtue point unto the Magnetical Meridian Line Take off the counterpoise then it sheweth the declination so that one and the self same Needle in the same place only by taking off and putting on a little piece of Wax sheweth plainly both those properties of directions and declinations and in like manner every inclinatory Needle will do if the points of his Axis be sharp and held in his box parallel to the Horizon he will shew both those properties of direction and declination a fine piece of Cork or Leather or any Tough substance may serve this Needle for a counterpoise in all Latitudes by thrusting it towards the center in the less Latitudes and towards the end in the greater and I think it not impossible but that a skilful Geometrician may so graduate the one half of such a Needle that it alone with its counterpoise may be a means to give a probable conjecture for the Latitude of any place whatsoever It will be very convenient in the next place to make a discovery of the Errours committed in making and touching Magnetical Needles and Wyers of Sayling Compasses and to give advise for the true and right making and touching of them First The Wyers that are commonly made both with us and in forrain Countries are of so base and drossie Iron not apt or sufficient to receive the tenth part of the virtue that fine steel Wyer could do Secondly The ends of the Wyers are for the most part not filed smooth nor â—itted even together upon the Axis of the file by means whereof the touch of the stone is more dully received and the standing of the file more uncertain the Magnetical force not being in the true Axis thereof Some who would seem to be of great skill have imagined that the best way to add strength to a Needle is with a Hammer to give some strokes to the point of the stone thereby causing Litrages as it were or Beard to hang down from it and that the Needle in his touching taking some part of that with him should have the stronger touch But they that so suppose deceive themselves therein for a Beard is nothing else but â—he fine dust of the stone hanging together by virtue â—hereof which being seperated from the stone alâ—hough it were a right good one is not able any whit â—t all to turn a Needle of it self The tryal is soon made by this means let them take off that beard from the stone with a stick and lay it upon the end of a Neeâ—le not touched and they shall find in it no force at all â—ay it is hurtful to the Needle for it giveth a superfluâ—us burthen for a small time and cannot but incumber â—is action by reason that every one of those little parâ—els of dust though beaten out at one end hath also â—or its small quantity both a North and a South virtue And therefore marreth as much as it maketh at either â—nd of the Needle The proof hereof is manifest if â—ou put off that dust or beard upon a paper and hold a â—oad-stone under it for as you turn towards the paper â—he North or South of the Stone so will every one of these particles in like manner turn it self shewing â—hereby a double nature
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