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 by Kircherus, 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 or Aqua fortis be 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 or exhalation, 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 in aqua fortis or 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 the Mummies; which still retains its attraction, though probably taken out of the Mine about two thousand years ago.
It is improbable what Pliny affirmeth concerning the object of its attraction, that it attracts not only ferreous bodies, but also liquorem 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 what Helmont delivereth 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 the Indies, 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, and Eusebius Nierembergius, a learned Jesuit of Spain delivers, 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. King Cheops in his Tomb, and the Jews in 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 of Paracelsus, 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 it Zibeta Occidentalis, Western Civet; making the face the East, but the posteriours the America or Western part of his Microcosm. The verity hereof might easily be tried in Wales, 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 of Britain Cæsar hath left some mention.
Another kind of verticity, is that which Angelus doce mihi jus, alias, Anagrammatically.Michael Sundevogis, in a Tract De 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 what Lælius Bisciola reporteth, 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 the Cœsius Bernardus a late Mineralogist, and originally confirmed by Porta, that Needles touched with a Diamond contract a verticity, even as they do with a Loadstone, which will not consist with experiment. And therefore, as Gilbertus observeth, he might be deceived, in touching such Needles with Diamonds, 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 place Fracastorius his attraction of silver. Philostratus his Pantarbes, Apollodorus and Beda his relation of the Loadstone that attracted onely in the night. But most inexcusable is Franciscus Rueus, a man of our own profession; who in his discourse of Gemms mentioned in the Apocalyps, 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. But Bœtius de Boot Physitian unto Rodulphus the second, hath recompenced this defect; and in his Tract De Lapidibus & Gemmis, speaks very materially hereof; and his Discourse is consonant unto Experience and Reason.