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
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
in the sides you spoile it with this Ovall form For the stone will not lightly be of one quarter of the force as it was before for the Ovall form giveth it no virtue but it is the fittest for it to shew the uttermost of that strength which of it self it had before if you observe the due points and not otherwise But in this Earth and Brick it is not possible to find the due points in such a manner as you may in a Load-stone because of the weakness of the Magnetical force therein contained And therefore you cannot bring that into a regular Ovall form and by the Fire take away the confused Magnetical force and all other perverse qualities thereof that being by nature a Magnetical body in his cooling before specified receiving presently by that unresistable power of the Earth his Magnetical virtue according unto that form and will regularly have his due points precisely in the ends without any confusion Johannes Babtista Porta writes that he did make tryal of the way that Paracelsus hath set down for to increase the virtue of a Magnet Namely to heat him red hot in the Fire and to quench him in the Oyl of Crocus Martis and Babtista Porta saith that he found it a detestable falsehood But saith he he is so far from increasing his virtue as that being once red hot he looseth all his own past all recovery But for all this that he saith I doubt whether Paracelsus be justly reproved or not for by my own experience I know that the heating of a Load-stone untill it be red hot doth weaken a Load-stone but taketh not away all its force and in my tryal hereof I found a very manifest proof of the Magnetisme of the Earth which I thought necessary to insert in this place I have made this tryal of fragments of Magnets in divers kinds and likewise of divers kinds of Iron Mines which are next in degree to the Magnets Namely after this manner Heat him in the Fire by little and little for fear of breaking untill he be red hot then take him out and let him cool then mark with Chalk or what you please those parts that respect the North and South and you shall find those markt places the North and the South Poles of the Magnet Put him into the fire again untill he be red hot and cool him contrarily and you shall have the contrary effect Therefore if Babtsta Porta did make his tryal with a Load-stone very long in form and chanced for Doctor Gilberts mistery of the Magnetisme was not then revealed for to cool him in his Oyl of Crocus Martis with his ends East and West the Axis of the stone being then overthwart in the middle it were no marvel though it found no force in the ends And I doe not think it impossible but that Paracelsus way may doe some good rightly used Doctor Gilbert writeth that some Iron Mine will affect a Magnetical Needle as it is of it self being unprepared by fire but as yet I never could find any such but this I have often tryed that it being of no manner of Magnetical virtue of it self no more then a Flint stone unprepared by fire being made red hot and cooled is presently impregnated with very apparent Magnetical virtue according to the scituation that he is cooled in and although you heat and cool him often and divers ways he will still keep his virtues according to the situation of his cooling And some Iron Mines I have found which being but in this sort prepared have had as strong force as some natural Magnets have had it is the goodness of the Load-stone joyned with a fit form that will shew great force For as a very good form with a base substance can doe but very little so the substance of the Load-stone be it never so excellent except it have some convenient form is not availeable For example an excellent Load-stone of a pound weight and of a good fashion being used artificially may take up four pounds of Iron beat it into small powder and it shall be of no force to take up one ounce of Iron yea I am very well assured that half an ounce of a Load-stone of good fashion anâ— of like virtue will take up more then a pound will doe being beaten in powder Whence to add to this by the way it appeareth manifestly that it is a great errour of those Physitians and Chirurgeons which to remedy Ruptures doe prescribe unto their Patients to take the powder of Load-stone inwardly and the small filling of Iron inwardly suppose here that the Magnetical drawing should do great wonders whereas they consider not that the stone being dissolved into powder every little particle of the dust hath two points contrary the one drawing to the other repelling and putting from and so being thus confounded by a contrary working doth much more harm then good with his Magnetical quality As for the astringent and drying property of the Load-stone I leave them to the diligent observation of those that are skilful in Physick but to return to our purpose and to alledge this also besides the manifest proof if the Earth were not by Nature a Magnetical body the aforesaid mentioned piece of Earth were not by Nature a Magnetical body the afore mentioned piece of Earth could not receive from a Load-stone any Magnetical power but most certain it is and by many undoubted experiments confired that it will evidently receive a Magnetical power from a Load-stone therefore it is manifest that the Earth is by nature a Magnetical power but most certain it is and by many undoubted experiments confirmed that it will evidently receive Magnetical power from a Load-stone therefore it is manifest that the Earth is by nature a Magnetical body Farthermore as amongst all the Mettalls Iron doth imcomparably more resemble the Earth in substance then any other doth it likewise doth participate more with the Earth in quality and principally in the Magnetical peculiar property hereof as notorious experience declareth yea every piece of Iron Oare being naturally as Doctor Gilbert sheweth a Magnet although of feeble force and all Magnets being a kind of an Iron Oare is the very cause that only Iron or Steel and no other Mettall is capable of that virtue Namely to have that revived and multiplyed by the vicinity of a Magnet which at the first in some measure was originally in it self as it is aforesaid it is also well known that the Magnet is a stone most commonly of invincible hardness nothing inferiour to any Iron or Steel of the excellentest sort notwithstanding sometimes we see of them that are nothing but a dry lump of Earth and yet of those also some are stronger in virtue than divers of the hard stones are which Earthly Magnets if a man assay to bring them into fashion by grinding on a Grinding-stone according to the common use they will consume into very Mud in the Water Now