What the variation of the Compass is.
It is also probable what is delivered concerning the variation of the Compass that is the cause and ground thereof, for the manner as being confirmed by observation we shall not at all dispute. The variation of the Compass is an Arch of the Horizon intercepted between the true and Magnetical Meridian; or more plainly, a deflexion and siding East and West from the true Meridian. The true Meridian is a major Circle passing through the Poles of the World, and the Zenith or Vertex of any place, exactly dividing the East from the West. Now on this line the Needle exactly lieth not, but diverts and varieth its point, that is, the North point on this side the Equator, the South on the other; sometimes on the East, sometime toward the West, and in some few places varieth not at all. First, therefore it is observed that betwixt the Shore ofIreland,France,Spain,Guiny, and theAzores, the North point varieth toward the East, and that in some variety; atLondonit varieth eleven degrees, atAntwerpnine, atRomebut five: at some parts of theAzoresit deflecteth not, but lieth in the true Meridian; on the other side of theAzores, and this side of the Equator, the Northpoint of the Needle wheeleth to the West; so that in the latitude of 36 near the shore, the variation is about eleven degrees; but on the other side the Equator, it is quite otherwise: for aboutCapio FrioinBrasilia, the South point varieth twelve degrees unto the West, and about the mouth of the Straits ofMagellanfive or six; but elongating from the coast ofBrasiliatoward the shore ofAfricait varieth Eastward, and arriving atCapo de las Agullas, it resteth in the Meridian, and looketh neither way.
The cause of the variation of the Compass.
Now the cause of this variation was thought byGilbertusto be the inequality of the Earth, variously disposed, and indifferently intermixed with the Sea: withal the different disposure of its Magnetical vigor in the eminencies and stronger parts thereof. For the Needle naturally endeavours to conform unto the Meridian, but being distracted, driveth that way where the greater and powerfuller part of the Earth is placed. Which may be illustrated from what hath been delivered and may be conceived by any that understands the generalities of Geography. For whereas on this side the Meridian, or the Isles ofAzores, where the first Meridian is placed, the Needle varieth Eastward; it may be occasioned by that vast Tract of Earth, that is, ofEurope,Asia, andAfrica, seated toward the East, and disposing the Needle that way. For arriving at some part of theAzores, or Islands of SaintMichael, which have a middle situation between these Continents, and that vast and almost answerable Tract ofAmerica, it seemeth equally distracted by both; and diverting unto neither, doth parallel and place it self upon the true Meridian. But sailing farther, it veers its Lilly to the West, and regardeth that quarter wherein the Land is nearer orgreater; and in the same latitude as it approacheth the shore augmenteth its variation. And therefore as some observe, ifColumbusor whosoever first discoveredAmerica, had apprehended the cause of this variation, having passed more then half the way, he might have been confirmed in the discovery, and assuredly foretold there lay a vast and mighty continent toward the West. The reason I confess and inference is good, but the instance perhaps not so. ForColumbusknew not the variation of the compass, whereofSebastian Cabotfirst took notice, who after made discovery in the Northern part of that continent. And it happened indeed that part ofAmericawas first discovered, which was on this side farthest distant, that is,Jamaica,Cuba, and the Isles in the Bay ofMexico. And from this variation do some new discoverers deduce a probability in the attempts of the Northern passage toward theIndies.
Now because where the greater continents are joyned, the action and effluence is also greater; therefore those Needles do suffer the greatest variation which are in Countries which most do feel that action. And therefore hathRomefar less variation thenLondon; for on the West side ofRomeare seated the great continents ofFrance,Spain,Germany, which take off the exuperance, and in some way ballance the vigor of the Eastern parts. But untoEnglandthere is almost no Earth West, but the whole extent ofEuropeandAsialieth Eastward; and therefore atLondonit varieth eleven degrees, that is almost oneRhomb. Thus also by reason of the great continent ofBrasilia,Peru, andChili, the Needle deflecteth toward the Land twelve degrees; but at the straits ofMagellanwhere the Land is narrowed, and the Sea on the other side, itvarieth but five or six. And so likewise, because the Capede las Agullashath Sea on both sides near it, and other Land remote, and as it were æquidistant from it, therefore at that point the Needle conforms unto the true Meridian, and is not distracted by the vicinity of Adjacencies. This is the general and great cause of variation. But if in certain Creeks and Vallies the Needle prove irregular, and vary beyond expectation, it may be imputed unto some vigorous part of the Earth, or Magnetical eminence not far distant. And this was the invention ofD. Gilbert, not many years past, a Physician inLondon. And therefore although some assume the invention of its direction, and other have had the glory of the Card; yet in the experiments, grounds, and causes thereof,Englandproduced the Father Philosopher, and discovered more in it thenColumbusorAmericusdid ever by it.
Unto this in great part true the reason ofKircherusmay be added: That this variation proceedeth not only from terrestrious eminencies, and magnetical veins of the Earth, laterally respecting the Needle, but the different coagmentation of the Earth disposed unto the Poles, lying under the Sea and Waters, which affect the Needle with great or lesser variation, according to the vigour or imbecility of these subterraneous lines, or the entire or broken compagination of the magnetical fabrick under it. As is observable from several Loadstones placed at the bottom of any water, for a Loadstone or Needle upon the surface, will variously conform it self, according to the vigour or faintness of the Loadstones under it.
Thus also a reason may be alledged for the variation of the variation, and why, according to observation, the variation of the Needle hath after some years beenfound to vary in some places. For this may proceed from mutations of the earth, by subterraneous fires, fumes, mineral spirits, or otherwise; which altering the constitution of the magnetical parts, in process of time, doth vary the variation over the place.
It is also probable what is conceived of its Antiquity, that the knowledge of its polary power and direction unto the North was unknown unto the Ancients; and thoughLevinus Lemnius, andCælius Colcagninus, are of another belief, is justly placed with new inventions byPancirollus. For theirAchillesand strongest argument is an expression inPlautus, a very Ancient author, and contemporary untoEnnius.Hic ventus jam secundus est, cape modo versoriam.Now thisversoriamthey construe to be the compass, which notwithstanding according untoPineda, who hath discussed the point,Turnebus,Cabeus, and divers others, is better interpreted the rope that helps to turn the Ship, or as we say, doth make it tack about; the Compass declaring rather the Ship is turned, then conferring unto its conversion. As for the long expeditions and sundry voyages of elder times, which might confirm the Antiquity of this invention, it is not improbable they were performed by the help of Stars; and so might the Phœnicean navigators, and alsoUlissessail about the Mediterranean, by the flight of Birds, or keeping near the shore; and so mightHannocoast aboutAfrica; or by the help of Oars, as is expressed in the voyage ofJonah. And whereas it is contended that this verticity was not unknown untoSolomon, in whom is presumed an universality of knowledge; it will as forcibly follow, he knew the Art of Typography, Powder and Guns, or had the Philosophers Stone, yet sent untoOphirfor Gold. It is not to be denied, thatbeside his Political wisdom, his knowledge in Philosophy was very large; and perhaps from his works therein, the ancient Philosophers, especiallyAristotle, who had the assistance ofAlexandersacquirements, collected great observables. Yet if he knew the use of the Compass, his Ships were surely very slow, that made a three years voyage fromEziongeberin the red Sea untoOphir; which is supposed to beTaprobanaorMalacain theIndies, not many moneths sail; and since in the same or lesser time,DrakeandCandishperformed their voyage about the Earth.
And as the knowledge of its verticity is not so old as some conceive, so it is more ancient then most believe; nor had its discovery with Guns, Printing, or as many think, some years before the discovery ofAmerica. For it was not unknown untoPetrus Peregrinusa Frenchman, who two hundred years since left a Tract of the Magnet, and a perpetual motion to be made thereby, preserved byGasserus.Paulus Venetus, and about five hundred years pastAlbertus Magnusmake mention hereof, and quote for it a Book ofAristotle,De Lapide; which Book although we find in the Catalogue ofLaertius, yet withCabeuswe may rather judge it to be the work of some Arabick Writer, not many years before the days ofAlbertus.
Lastly, It is likewise true what some have delivered ofCrocus Martis, that is, Steel corroded with Vinegar, Sulphur, or otherwise, and after reverberated by fire. For the Loadstone will not at all attract it, nor will it adhere, but lye therein like Sand. This to be understood ofCrocus Martiswell reverberated, and into a violet colour: for commonchalybs præparatus, or corroded and powdered Steel, the Loadstone attracts like ordinary filings of Iron; and many times most ofthat which passeth forCrocus Martis. So that this way may serve as a test of its preparation; after which it becometh a very good medicine in fluxes. The like may be affirmed of flakes of Iron that are rusty and begin to tend unto Earth; for their cognation then expireth, and the Loadstone will not regard them.
And therefore this may serve as a trial of good Steel. The Loadstone taking up a greater mass of that which is most pure, it may also decide the conversion of Wood into Iron, as is pretended from some Waters: and the common conversion of Iron into Copper by the mediation of blew Coperose, for the Loadstone will not attract it. Although it may be questioned, whether in this operation, the Iron or Coperose be transmuted, as may be doubted from the cognation of Coperose with Copper; and the quantity of Iron remaining after the conversion. And the same may be useful to some discovery concerning Vitriol or Coperose of Mars, by some called Salt of Steel, made by the spirits of Vitriol or Sulphur. For the corroded powder of Steel will after ablution be actively attracted by the Loadstone, and also remaineth in little diminished quantity. And therefore whether those shooting Salts partake but little of Steel, and be not rather the vitriolous spirits fixed into Salt by the effluvium or odor of Steel, is not without good question.
Concerning the Loadstone, therein of sundry common Opinions, and received several relations: Natural, Historical, Medical, Magical.
And first not only a simple Heterodox, but a very hard Paradox, it will seem, and of great absurdity unto obstinate ears, if we say, attraction is unjustly appropriated unto the Loadstone, and that perhaps we speak not properly, when we say vulgarly and appropriately the Loadstone draweth Iron; and yet herein we should not want experiment and great authority. The words ofRenatus des Cartesin his Principles of Philosophy are very plain.Præterea magnes trahet ferrum, sive potius magnes & ferrum ad invicem accedunt, neque enim ulla ibi tractio est.The same is solemnly determined byCabeus.Nec magnes trahit proprie ferrum, nec ferrum ad se magnetem provocat, sed ambo pari conatu ad invicem confluunt.Concordant hereto is the assertion of DoctorRidley, Physitian unto the Emperour ofRussia, in his Tract of Magnetical Bodies, defining Magnetical attraction to be a natural incitation and disposition conforming unto contiguity, an union of one Magnetical Body with another, and no violent haling of the weak unto the stronger. And this is also the doctrine ofGilbertus, by whom this motion is termed Coition, and that not made by any faculty attractive of one, but a Syndrome and concourse of each; a Coition alway of their vigours, and also of their bodies, if bulk or impediment prevent not. Andtherefore those contrary actions which flow from opposite Poles or Faces, are not so properly expulsion and attraction, asSequelaandFuga, a mutual flight and following. Consonant whereto are also the determination ofHelmontius,Kircherus, andLicetus.
Attraction reciprocal betwixt the Loadstone and Iron.
The same is also confirmed by experiment; for if a piece of Iron be fastened in the side of a bowl or bason water, a Loadstone swimming freely in a Boot of Cork, will presently make unto it. So if a Steel or Knife untouched, be offered toward the Needle that is touched, the Needle nimbly moveth toward it, and conformeth unto union with the Steel that moveth not. Again, If a Loadstone be finely filed, the Atoms or dust thereof will adhere unto Iron that was never touched, even as the powder of Iron doth also unto the Loadstone. And lastly, if in two Skiffs of Cork, a Loadstone and Steel be placed within the Orb of their activities, the one doth not move the other standing still, but both hoise sail and steer unto each other. So that if the Loadstone attract, the Steel hath also its attraction; for in this action the Alliciency is reciprocal, which joyntly felt, they mutually approach and run into each others arms.
And therefore surely more moderate expressions become this action, then what the Ancients have used, which some have delivered in the most violent terms of their language; soAustincalls it,Mirabilem ferri raptorem:Hippocratesλίθος τὸν σίδηρον ἁρπάζει,Lapis qui ferrum rapit.Galendisputing againstEpicurususeth the term ἕλκειν, but this also is too violent: among the AncientsAristotlespake most warily, ὅστις τὸν σίδηρον κινεῖ,Lapis qui ferrum movet: and in some tolerable acception do run the expressions ofAquinas,ScaligerandCusanus.
Many relations are made, and great expectations are raised from theMagnes Carneus, or a Loadstone, that hath a faculty to attract not only iron but flesh; but this upon enquiry, and asCabeusalso observed, is nothing else but a weak and inanimate kind of Loadstone, veined here and there with a few magnetical and ferreous lines; but consisting of a bolary and clammy substance, whereby it adheres likeHæmatites, orTerra Lemnia, unto the Lips. And this is that stone which is to be understood, when Physitians joyn it withÆtites, or the Eagle stone, and promise therein a vertue against abortion.
There is sometime a mistake concerning the variation of the Compass, and therein one point is taken for another. For beyond that Equator some men account its variation by the diversion of the Northern point, whereas beyond that Circle the Southern point is Soveraign, and the North submits his preheminency. For in the Southern coast either ofAmericaorAfrica, the Southern point deflects and varieth toward the Land, as being disposed and spirited that way by the Meridional and proper Hemisphere. And therefore on that side of the Earth the varying point is best accounted by the South. And therefore also the writings of some, and Maps of others, are to be enquired, that make the Needle decline unto the East twelve degrees atCapo Frio, and six at the straits ofMagellan; accounting hereby one point for another, and preferring the North in the Liberties and Province of the South.
That Garlick hinders not the attraction of the Loadstone.
But certainly false it is what is commonly affirmed and believed, that Garlick doth hinder the attraction of the Loadstone, which is notwithstanding delivered by grave and worthy Writers, byPliny,Solinus,Ptolemy,Plutarch,Albertus,Mathiolus,Rueus,Langius,and many more. An effect as strange as that ofHomers Moly, and the Garlick thatMercurybestowed uponUlysses. But that it is evidently false, many experiments declare. For an Iron wire heated red hot and quenched in the juice of Garlick, doth notwithstanding contract a verticity from the Earth, and attracteth the Southern point of the Needle. If also the tooth of a Loadstone be covered or stuck in Garlick, it will notwithstanding attract; and Needles excited and fixed in Garlick until they begin to rust, do yet retain their attractive and polary respects.
Nor yet the Adamant or Diamond.
Of the same stamp is that which is obtruded upon us by Authors ancient and modern, that an Adamant or Diamond prevents or suspends the attraction of the Loadstone: as is in open terms delivered byPliny.Adamas dissidet cum Magnete lapide, ut juxta positus ferrum non patiatur abstrahi, aut si admotus magnes, apprehenderit, rapiat atque auferat. For if a Diamond be placed between a Needle and a Loadstone, there will nevertheless ensue a Coition even over the body of the Diamond. And an easie matter it is to touch or excite a Needle through a Diamond, by placing it at the tooth of a Loadstone; and therefore the relation is false, or our estimation of these gemms untrue; nor are they Diamonds which carry that name amongst us.
De generatione rerum.
It is not suddenly to be received whatParacelsusaffirmeth, that if a Loadstone be anointed with Mercurial oyl, or onely put into Quicksilver, it omitteth its attraction for ever. For we have found that Loadstones and touched Needles which have laid long time in Quicksilver have not amitted their attraction. And we also find that red hot Needles or wires extinguished in Quicksilver, do yet acquire a verticity according to the Laws of position in extinction. Of greater repugnancy unto reason is that which he delivers concerning its graduation, that heated in fire and often extinguished in oyl of Mars or Iron, it acquires an ability to extract or draw forth a nail fastened in a wall; for, as we have declared before, the vigor of the Loadstone is destroyed by fire, nor will it be re-impregnated by any other Magnete then the Earth.
Nor is it to be made out what seemeth very plausible, and formerly hath deceived us, that a Loadstone will not attract an Iron or Steel red hot. The falsity hereof discovered first byKircherus, we can confirm by iterated experiment; very sensibly in armed Loadstones, and obscurely in any other.
True it is, that besides fire some other wayes there are of its destruction, as Age, Rust; and what is least dreamt on, an unnatural or contrary situation. For being impolarily adjoyned unto a more vigorous Loadstone, it will in a short time enchange its Poles; or being kept in undue position, that is, not lying on the Meridian, or else with its poles inverted, it receives in longer time impair in activity, exchange of Faces; and is more powerfully preserved by position then by the dust of Steel. But the sudden and surest way is fire; that is, fire not onely actual but potential; the one surely and suddenly, the other slowly and imperfectly; the one changing, the other destroying the figure. For if distilled Vinegar orAqua fortisbe poured upon the powder of Loadstone, the subsiding powder dryed, retains some Magnetical vertue, and will be attracted by the Loadstone: but if the menstruum or dissolvent be evaporated to a consistence, and afterward doth shoot into Icycles or Crystals, the Loadstone hath no power upon them; and if in a full dissolution of Steel a separation of parts be made by precipitation orexhalation, the exsiccated powder hath lost its wings and ascends not unto the Loadstone. And though a Loadstone fired doth presently omit its proper vertue, and according to the position in cooling contracts a new verticity from the Earth; yet if the same be laid awhile inaqua fortisor other corrosive water, and taken out before a considerable corrosion, it still reserves its attraction, and will convert the Needle according to former polarity. And that duly preserved from violent corrosion, or the natural disease of rust, it may long conserve its vertue, beside the Magnetical vertue of the Earth, which hath lasted since the Creation, a great example we have from the observation of our learned friend Mr.Graves,In his learned Pyramidographia.in an Ægyptian Idol cut out of Loadstone, and found among theMummies; which still retains its attraction, though probably taken out of the Mine about two thousand years ago.
It is improbable whatPlinyaffirmeth concerning the object of its attraction, that it attracts not only ferreous bodies, but alsoliquorem vitri; for in the body of Glass there is no ferreous or magnetical nature which might occasion attraction. For of the Glass we use, the purest is made of the finest sand and the ashes of Chali or Glaswort, and the courser or green sort of the ashes of Brake or other plants. True it is that in the making of Glass, it hath been an ancient practice to cast in pieces of magnet, or perhaps manganes: conceiving it carried away all ferreous and earthy parts, from the pure and running portion of Glass, which the Loadstone would not respect; and therefore if that attraction were not rather Electrical then Magnetical, it was a wondrous effect whatHelmontdelivereth concerning a Glass wherein the Magistery of Loadstone was prepared, which after retained an attractive quality.
But whether the Magnet attracteth more then common Iron, may be tried in other bodies. It seems to attract the Smyris or Emery in powder; It draweth the shining or glassie powder brought from theIndies, and usually implied in writing-dust. There is also in Smiths Cinders by some adhesion of Iron whereby they appear as it were glazed, sometime to be found a magnetical operation; for some thereof applied have power to move the Needle. But whether the ashes of vegetables which grow over Iron Mines contract a magnetical quality, as containing some mineral particles, which by sublimation ascend unto their Roots, and are attracted together with their nourishment; according as some affirm from the like observations upon the Mines of Silver, Quick silver, and Gold, we must refer unto further experiment.
It is also improbable and something singular what some conceive, andEusebius Nierembergius, a learned Jesuit ofSpaindelivers, that the body of man is magnetical, and being placed in a Boat, the Vessel will never rest untill the head respecteth the North. If this be true, the bodies of Christians do lye unnaturally in their Graves. KingCheopsin his Tomb, and theJewsin their beds have fallen upon the natural position: who reverentially declining the situation of their Temple, nor willing to lye as that stood, do place their Beds from North to South, and delight to sleep Meridionally. This Opinion confirmed would much advance the Microcosmical conceit, and commend the Geography ofParacelsus, who according to the Cardinal points of the World divideth the body of man: and therefore working upon humane ordure, and by long preparation rendring it odoriferous, he terms itZibeta Occidentalis, WesternCivet; making the face the East,but the posteriours theAmericaor Western part of his Microcosm. The verity hereof might easily be tried inWales, where there are portable Boats, and made of Leather, which would convert upon the impulsion of any verticity; and seem to be the same whereof in his description ofBritainCæsarhath left some mention.
Another kind of verticity, is that whichAngelus doce mihi jus,alias,Anagrammatically.Michael Sundevogis, in a TractDe Sulphure, discovereth in Vegetables, from sticks let fall or depressed under water; which equally framed and permitted unto themselves, will ascend at the upper end, or that which was vertical in their vegetation; wherein notwithstanding, as yet, we have not found satisfaction. Although perhaps too greedy of Magnalities, we are apt to make but favourable experiments concerning welcome Truths, and such desired verities.
It is also wondrous strange whatLælius Bisciolareporteth, that if unto ten ounces of Loadstone one of Iron be added, it encreaseth not unto eleven, but weighs ten ounces still.Horæ subsecivæ.A relation inexcusable in a work of leisurable hours: the examination being as ready as the relation, and the falsity tried as easily as delivered. Nor is it to be omitted what is taken up by theCœsius Bernardusa late Mineralogist, and originally confirmed byPorta, that Needles touched with aDiamondcontract a verticity, even as they do with a Loadstone, which will not consist with experiment. And therefore, asGilbertusobserveth, he might be deceived, in touching such Needles withDiamonds, which had a verticity before, as we have declared most Needles to have; and so had he touched them with Gold or Silver, he might have concluded a magnetical vertue therein.
In the same form may we placeFracastoriushis attraction of silver.PhilostratushisPantarbes,ApollodorusandBedahis relation of the Loadstone that attracted onely in the night. But most inexcusable isFranciscus Rueus, a man of our own profession; who in his discourse ofGemmsmentioned in theApocalyps, undertakes a Chapter of the Loadstone. Wherein substantially and upon experiment he scarce delivereth any thing: making long enumeration of its traditional qualities, whereof he seemeth to believe many, and some above convicted by experience, he is fain to salve as impostures of the Devil. ButBœtius de BootPhysitian untoRodulphusthe second, hath recompenced this defect; and in his TractDe Lapidibus & Gemmis, speaks very materially hereof; and his Discourse is consonant unto Experience and Reason.
As for Relations Historical, though many there be of less account, yet two alone deserve consideration: The first concerneth magnetical Rocks, and attractive Mountains in several parts of the Earth. The other the Tomb ofMahometand bodies suspended in the air. Of Rocks magnetical there are likewise two relations; for some are delivered to be in theIndies, and some in the extremity of the North, and about the very Pole. The Northern account is commonly ascribed untoOlaus MagnusArchbishop ofUpsale, who out of his PredecessorJoannes,Saxo, and others, compiled a History of some Northern Nations; but this assertion we have not discovered in that Work of his which commonly passeth amongst us, and should believe his Geography herein no more then that in the first line of his Book; when he affirmeth thatBiarmia(which is not seventy degrees in latitude) hath the Pole for its Zenith, and Equinoctial for the Horizon.
Now upon this foundation, how uncertain soever men have erected mighty illations, ascribing thereto the cause of the Needles direction, and conceiving the effluctions from these Mountains and Rocks invite the Lilly toward the North. Which conceit though countenanced by learned men, is not made out either by experience or reason, for no man hath yet attained or given a sensible account of the Pole by some degrees. It is also observed the Needle doth very much vary as it approacheth the Pole; whereas were there such direction from the Rocks, upon a nearer approachment it would more directly respect them. Beside, were there such magnetical Rocks under the Pole, yet being so far removed they would produce no such effect. For they that sail by the Isle ofIluanow calledElbain the Thuscan Sea which abounds in veins of Loadstone, observe no variation or inclination of the Needle; much less may they expect a direction from Rocks at the end of the Earth. And lastly, men that ascribe thus much unto Rocks of the North, must presume or discover the like magneticals at the South: For in the Southern Seas and far beyond the Equator, variations are large, and declinations as constant as in the Northern Ocean.
(Probably) there be no magnetical Rocks.
The other relation of Loadstone Mines and Rocks, in the shore ofIndiais delivered of old byPliny; wherein, saith he, they are so placed both in abundance and vigour, that it proves an adventure of hazard to pass those Coasts in a Ship with Iron nails.Serapionthe Moor, an Author of good esteem and reasonable Antiquity, confirmeth the same, whose expression in the wordmagnesis this. The Mine of this Stone is in the Sea-coast ofIndia, whereto when Ships approach, there is no Iron in them which flies not like a Birdunto those Mountains; and therefore their ships are fastened not with Iron but Wood, for otherwise they would be torn to pieces. But this assertion, how positive soever, is contradicted by all Navigators that pass that way; which are now many, and of our own Nation, and might surely have been controled byNearchusthe Admiral ofAlexander; who not knowing the Compass, was fain to coast that shore.
Mahomet'stomb of stone, and built upon the ground.
For the relation concerningMahomet, it is generally believed his Tomb atMedina Talnabi, inArabia, without any visible supporters hangeth in the air between two Loadstones artificially contrived both above and below; which conceit is fabulous and evidently false from the testimony of Ocular Testators, who affirm his Tomb is made of Stone, and lyeth upon the ground; as beside others the learnedVossiusobserveth fromGabriel Sionita, andJoannes Hesronita, twoMaronitesin their relations hereof. Of such intentions and attempt byMahometanswe read in some Relators, and that might be the occasion of the Fable, which by tradition of time and distance of place enlarged into the Story of being accomplished. And this hath been promoted by attempts of the like nature; for we read inPlinythat oneDinocratesbegan to Arch the Temple ofArsinoeinAlexandriawith Loadstone, that so her Statue might be suspended in the air to the amazement of the beholders. And to lead on our crudelity herein, confirmation may be drawn from History and Writers of good authority. So it is reported byRuffinus, that in the Temple ofSerapisthere was an Iron Chariot suspended by Loadstones in the air; which stones removed, the Chariot fell and dashed into pieces. The like dothBedareport ofBellerophonsHorse, which framed of Iron,was placed between two Loadstones, with wings expansed, pendulous in the air.
The verity of these Stories we shall not further dispute, their possibility we may in some way determine; if we conceive what no man will deny, that bodies suspended in the air have this suspension from one or many Loadstones placed both above and below it; or else by one or many placed only above it. Likewise the body to be suspended in respect of the Loadstone above, is either placed first at a pendulous distance in the medium, or else attracted unto that site by the vigor of the Loadstone. And so we first affirm, that possible it is, a body may be suspended between two Loadstones; that is, it being so equally attracted unto both, that it determineth it self unto neither. But surely this position will be of no duration; for if the air be agitated or the body waved either way, it omits the equilibration, and disposeth it self unto the nearest attractor. Again, It is not impossible (though hardly feasible) by a single Loadstone to suspend an Iron in the air, the Iron being artificially placed and at a distance guided toward the stone, until it find the neutral point, wherein its gravity just equals the magnetical quality, the one exactly extolling as much as the other depresseth. And lastly, Impossible it is that if an Iron rest upon the ground, and a Loadstone be placed over it, it should ever so arise as to hang in the way or medium; for that vigor which at a distance is able to overcome the resistance of its gravity and to lift it up from the Earth, will as it approacheth nearer be still more able to attract it; never remaining in the middle that could not abide in the extreams. Now the way ofBaptista Portathat by a thred fastneth a Needle to aTable, and then so guides and orders the same, that by the attraction of the Loadstone it abideth in the air, infringeth not this reason; for this is a violent retention, and if the thred be loosened, the Needle ascends and adheres unto the Attractor.
Powder of Loadstones, of what operation.
The third consideration concerneth Medical relations; wherein what ever effects are delivered, they are either derived from its mineral and ferreous condition, or else magnetical operation. Unto the ferreous and mineral quality pertaineth whatDioscoridesan ancient Writer and Souldier underAnthonyandCleopatraaffirmeth, that half a dram of Loadstone given with Honey and Water, proves a purgative medicine, and evacuateth gross humours. But this is a quality of great incertainty; for omitting the vehicle of Water and Honey, which is of a laxative power it self, the powder of some Loadstones in this dose doth rather constipate and binde, then purge and loosen the belly. And if sometimes it cause any laxity, it is probably in the same way with Iron and Steel unprepared, which will disturb some bodies, and work by Purge and Vomit. And therefore, whereas it is delivered in a Book ascribed untoGalen, that it is a good medicine in dropsies, and evacuates the waters of persons so affected: It may I confess by siccity and astriction afford a confirmation unto parts relaxed, and such as be hydropically disposed; and by these qualities it may be useful inHerniasorRuptures, and for these it is commended byÆtius,Ægineta, andOribatius; who only affirm that it contains the vertue ofHæmatites, and being burnt was sometimes vended for it. Wherein notwithstanding there is an higher vertue; and in the same prepared, or in rich veins thereof, though crude, we have observed the effects of ChalybeatMedicines; and the benefits of Iron and Steel in strong obstructions. And therefore that was probably a different vein of Loadstone, or infected with other mineral mixture, which the Ancients commended for a purgative medicine, and ranked the same with the violentest kinds thereof: withHippophae,Cneoron, andThymelæa, as we find it inHippocratesDe morbis internis.; and might be somewhat doubtful, whether by the magnesian stone, he understood the Loadstone; did notAchilles Statiusdefine the same, the Stone that loveth Iron.
To this mineral condition belongeth what is delivered by some, that wounds which are made with weapons excited by the Loadstone, contract a malignity, and become of more difficult cure; which nevertheless is not to be found in the incision of Chyrurgions with knives and lances touched; which leave no such effect behind them. Hither we also refer that affirmative, which sayes the Loadstone is poison; and therefore in the lists of poisons we find it in many Authors. But this our experience cannot confirm, and the practice of the King ofZeilanclearly contradicteth; who asGarcias ab Horto, Physitian unto theSpanishViceroy delivereth, hath all his meat served up in dishes of Loadstone, and conceives thereby he preserveth the vigour of youth.
But surely from a magnetical activity must be made out what is let fall byÆtius, that a Loadstone held in the hand of one that is podagrical, doth either cure or give great ease in the Gout. Or whatMarcellus Empericusaffirmeth, that as an amulet, it also cureth the headach; which are but additions unto its proper nature, and hopeful enlargements of its allowed attraction. For perceiving its secret power to draw magnetical bodies, men have invented a new attraction, todraw out the dolour and pain of any part. And from such grounds it surely became a philter, and was conceived a medicine of some venereal attraction; and therefore upon this stone they graved the Image ofVenus, according unto that ofClaudian,Venerem magnetica gemma figurat. Hither must we also ruler what is delivered concerning its power to draw out of the body bullets and heads of arrows, and for the like intention is mixed up in plaisters. Which course, although as vain and ineffectual it be rejected by many good Authors, yet is it not methinks so readily to be denied, nor the Practice of many Physicians which have thus compounded plaisters, thus suddenly to be condemned, as may be observed in theEmplastrum divinum Nicolai, theEmplastrum nigrumofAugspurg, theOpodeldochandAttractivumofParacelsus, with several more in the Dispensatory ofWecker, and practice ofSennertus. The cure also ofHernias, orRupturesinPareus: and the method also of curation lately delivered byDaniel Beckherus,[D]and approved by the Professors ofLeyden, that is, of a young man ofSprucelandthat casually swallowed a knife about ten inches long, which was cut out of his stomach, and the wound healed up. In which cure to attract the knife to a convenient situation, there was applied a plaister made up with the powder of Loadstone. Now this kind of practiceLibavius,Gilbertus, and latelySwickardusIn his Ars Magnetica.condemn, as vain, and altogether unuseful; because a Loadstone in powder hath no attractive power; for in that form it omits his polarly respects, and loseth those parts which are the rule of attraction.
Wherein to speak compendiously, if experiment hath not deceived us, we first affirm that a Loadstone inpowder omits not all attraction. For if the powder of a rich vein be in a reasonable quantity presented toward the Needle freely placed, it will not appear to be void of all activity, but will be able to stir it. Nor hath it only a power to move the Needle in powder and by it self, but this will it also do, if incorporated and mixed with plaisters; as we have made trial in theEmplastrum de Minia, with half an ounce of the mass, mixing a dram of Loadstone. For applying the magdaleon or roal unto the Needle, it would both stir and attract it; not equally in all parts, but more vigorously in some, according unto the Mine of the Stone, more plentifully dispersed in the mass. And lastly, In the Loadstone powdered, the polary respects are not wholly destroyed. For those diminutive particles are not atomical or meerly indivisible, but consist of dimensions sufficient for their operations, though in obscurer effects. Thus if unto the powder of Loadstone or Iron we admove the North Pole of the Loadstone, the Powders or small divisions will erect and conform themselves thereto: but if the South Pole approach, they will subside, and inverting their bodies, respect the Loadstone with the other extream. And this will happen not only in a body of powder together, but in any particle or dust divided from it.
Now though we disavow not these plaisters, yet shall we not omit two cautions in their use, that therein the Stone be not too subtilly powdered, for it will better manifest its attraction in a more sensible dimension. That where is desired a speedy effect, it may be considered whether it were not better to relinquish the powdered plaisters, and to apply an entire Loadstone unto the part: And though the other be not wholly ineffectual, whether this way be not more powerful,and so might have been in the cure of the young man delivered byBeckerus.
The last consideration concerneth Magical relations; in which account we comprehend effects derived and fathered upon hidden qualities, specifical forms, Antipathies and Sympathies, whereof from received grounds of Art, no reasons are derived. Herein relations are strange and numerous; men being apt in all Ages to multiply wonders, and Philosophers dealing with admirable bodies, as Historians have done with excellent men, upon the strength of their great atcheivements, ascribing acts unto them not only false but impossible; and exceeding truth as much in their relations, as they have others in their actions. Hereof we shall briefly mention some delivered by Authors of good esteem: whereby we may discover the fabulous inventions of some, the credulous supinity of others, and the great disservice unto truth by both: multiplying obscurities in Nature, and authorising hidden qualities that are false; whereas wise men are ashamed there are so many true.
And first,Dioscoridesputs a shrewd quality upon it, and such as men are apt enough to experiment, who therewith discovers the incontinency of a wife, by placing the Loadstone under her pillow, whereupon she will not be able to remain in bed with her husband. The same he also makes a help unto thievery. For Thieves saith he, having a design upon a house, do make a fire at the four corners thereof, and cast therein the fragments of Loadstone: whence ariseth a fume that so disturbeth the inhabitants, that they forsake the house and leave it to the spoil of the Robbers. This relation, how ridiculous soever, hathAlbertustaken up above a thousand years after, andMarbodeusthe Frenchman hath continued the same in Latine Verse, which with the Notes ofPictoriusis currant unto our dayes. As strange must be the Lithomancy or divination from this Stone, whereby asTzetzesdelivers,Helenusthe Prophet foretold the destruction ofTroy: and the Magick thereof not safely to be believed, which was delivered byOrpheus, that sprinkled with water it will upon a question emit a voice not much unlike an Infant. But surely the Loadstone ofLaurentius Guascusthe Physitian, is never to be matched; wherewith, asCardandelivereth, whatsoever Needles or Bodies were touched, the wounds and punctures made thereby, were never felt at all. And yet as strange is that which is delivered by some, that a Loadstone preserved in the salt of aRemora, acquires a power to attract gold out of the deepest Wells. Certainly a studied absurdity, not casually cast out, but plotted for perpetuity: for the strangeness of the effect ever to be admired, and the difficulty of the trial never to be convicted.
These conceits are of that monstrosity that they refute themselves in their recitements. There is another of better notice, and whispered thorow the World with some attention; credulous and vulgar auditors readily believing it, and more judicious and distinctive heads, not altogether rejecting it. The conceit is excellent, and if the effect would follow, somewhat divine; whereby we might communicate like spirits, and confer on earth withMenippusin the Moon. And this is pretended from the sympathy of two Needles touched with the same Loadstone, and placed in the center of two Abecedary circles or rings, with letters described round about them, one friend keeping one, and another the other, and agreeing uponan hour wherein they will communicate. For then, saith Tradition, at what distance of place soever, when one Needle shall be removed unto any letter, the other by a wonderful sympathy will move unto the same. But herein I confess my experience can find no truth; for having expressly framed two circles of Wood, and according to the number of the Latine letters divided each into twenty three parts, placing therein two stiles or Needles composed of the same steel, touched with the same Loadstone, and at the same point: of these two, whensoever I removed the one, although but at the distance of half a span, the other would stand likeHerculespillars, and if the Earth stand still, have surely no motion at all. Now as it is not possible that any body should have no boundaries, or Sphear of its activity, so it is improbable it should effect that at distance, which nearer hand it cannot at all perform.
Again, The conceit is ill contrived, and one effect inferred, whereas the contrary will ensue. For if the removing of one of the Needles fromAtoB, should have any action or influence on the other, it would not intice it fromAtoB, but repell it fromAtoZ: for Needles excited by the same point of the stone, do not attract, but avoid each other, even as these also do, when their invigorated extreams approach unto one other.
Lastly, Were this conceit assuredly true, yet were it not a conclusion at every distance to be tried by every head: it being no ordinary or Almanack business, but a Problem Mathematical, to finde out the difference of hours in different places; nor do the wisest exactly satisfie themselves in all. For the hours of several places anticipate each other, according unto their Longitudes, which are not exactly discovered of everyplace; and therefore the trial hereof at a considerable interval, is best performed at the distance of theAntœci; that is, such habitations as have the same Meridian and equal parallel, on different sides of the Æquator; or more plainly the same Longitude and the same Latitude unto the South, which we have in the North. For unto such situations it is noon and midnight at the very same time.
And therefore the Sympathy of these Needles is much of the same mould with that intelligence which is pretended from the flesh of one body transmuted by incision into another.De curtorum Chyrurgia.For if by the Art ofTaliacotius, a permutation of flesh, or transmutation be made from one mans body into another, as if a piece of flesh be exchanged from the bicipital muscle of either parties arm, and about them both an Alphabet circumscribed; upon a time appointed as some conceptions affirm, they may communicate at what distance soever. For if the one shall prick himself inA, the other at the same time will have a sense thereof in the same part: and upon inspection of his arm perceive what letters the other points out in his. Which is a way of intelligence very strange: and would requite the lost Art ofPythagoras, who could read a reverse in the Moon.
Now this magnetical conceit how strange soever, might have some original in Reason; for men observing no solid body, whatsoever did interrupt its action, might be induced to believe no distance would terminate the same; and most conceiving it pointed unto the Pole of Heaven, might also opinion that nothing between could restrain it. Whosoever was the Author, theÆolusthat blew it about wasFamianus Strada, that Elegant Jesuit, in his Rhetorical prolusions, who chose out this subject to express the stile ofLucretius.But neitherBaptista Porta,de Furtivis Literarum notis;Trithemiusin his Steganography,Selenusin his Cryptography,Nunc. inanim.by D.GodwinBishop of Hereford.Nuncius inanimatusmake any consideration hereof, although they deliver many ways to communicate thoughts at distance. And this we will not deny may in some manner be effected by the Loadstone; that is, from one room into another; by placing a table in the wall common unto both, and writing thereon the same letters one against another: for upon the approach of a vigorous Loadstone unto a letter on this side, the Needle will move unto the same on the other. But this is a very different way from ours at present; and hereof there are many ways delivered, and more may be discovered which contradict not the rule of its operations.
As forUnguentum Armarium, called alsoMagneticum, it belongs not to this discourse, it neither having the Loadstone for its ingredient, nor any one of its actions: but supposeth other principles, as common and universal spirits, which convey the action of the remedy unto the part, and conjoins the vertue of bodies far disjoyned. But perhaps the cures it doth, are not worth so mighty principles; it commonly healing but simple wounds, and such as mundified and kept clean, do need no other hand then that of Nature, and the Balsam of the proper part. Unto which effect there being fields of Medicines, it may be a hazardous curiosity to rely on this; and because men say the effect doth generally follow, it might be worth the experiment to try, whether the same will not ensue, upon the same Method of cure, by ordinary Balsams, or common vulnerary plaisters.
Many other Magnetisms may be pretended, and the like attractions through all the creatures of Nature.Whether the same be verified in the action of the Sun upon inferiour bodies, whether there beÆolianMagnets, whether the flux and reflux of the Sea be caused by any Magnetism from the Moon; whether the like be really made out, or rather Metaphorically verified in the sympathies of Plants and Animals, might afford a large dispute; andKircherusin hisCatena Magneticahath excellently discussed the same; which work came late unto our hand, but might have much advantaged this Discourse.
Other Discourses there might be made of the Loadstone: as Moral, Mystical, Theological; and some have handsomely done them; asAmbrose,Austine,Gulielmus Parisiensis, and many more, but these fall under no Rule, and are as boundless as mens inventions. And though honest minds do glorifie God hereby; yet do they most powerfully magnifie him, and are to be looked on with another eye, who demonstratively set forth its Magnalities; who not from postulated or precarious inferences, entreat a courteous assent; but from experiments and undeniable effects, enforce the wonder of its Maker.