An history of the wonderful things of nature set forth in ten severall classes wherein are contained I. The wonders of the heavens, II. Of the elements, III. Of meteors, IV. Of minerals, V. Of plants, VI. Of birds, VII. Of four-footed beasts, VIII. Of insects, and things wanting blood, IX. Of fishes, X. Of man
Jonstonus, Joannes, 1603-1675., Libavius, Andreas, d. 1616., Rowland, John, M.D.

CHAP. XV. Of the Loadstone.

THe Loadstone is well known: The effects of it are admirable, two are special, its turning to the poles of the World, and its dawing of another Loadstone and Iron. As for the first, in many places it doth nor exactly respect the poles, the Declination is som∣times more or lesse. This age observeth, that for 10 degrees beyond the fortunate Islands, where Cosmographers have set the beginning of Longitude, it concurs with the poles of the World; toward the East it varies more: About Norimberg, they count 10 degrees, in Nor∣way 16, in Zembla 17, as the Dutch observed; but one Gilbertus hath found out 23 degrees variation. Whence we collect the greatest varia∣tion to be 23 degrees. If we ask the cause, the learned are of divers opinions, some say there are certain Mountains of Loadstones under the poles, and they say the Loadstone moves by sympathy. Others write that it turns to certain Starrs. Others say there are in it two opposite points, whereof the one turns to the North, the other to the South. Others think, that it moves toward the South, because the operation of all the Planets is Southward. They all seem to be de∣ceived. How great and what kind of Mountains these are, is yet unknown, and there are many Mines of it in Aegypt. It doth not directly point at the Pole, unlesse it stand in the Meridian. The point that is toward the South, is held the stronger. The work-Ma∣sters gives us a notable Maxime, when in the finger of the Marriners Chart, they rub that part of the neidle with the Loadstone, wherewith it turns to the South. Lastly there are opposite places, wherein the Eccliptick declines from the Aequator toward the North, and the Planets from the East make their motions by the North. It seems Page  104 most probable, Sennert, l. 5. scient. natural. c. 4. that the Loadstone moves toward the South pole, either only, or if it hath two motions, the greatest is Southward. Let it suffice what Scaliger writes Exerc. 131. Nature, saith he, is at concord, and agrees with her self, she unites by an admirable order, all things above and below, that it may be one by a perpetual necessity. So that there are in things seperated not only steps, entrances, and retreats, but also minglings of those things which seem to be wholly parted. Bodinus pronounceth that all the 4, parts of the world are equally respected by the Loadstone Theatr. natur. l. 2. For (saith he) the steel needle easily rubbed upon the Loadstone, from that part of the Loadstone that pointed North before it was cut out of the rock, if the needle be equally ballanced, the end rubbed with the Loadstone will turn to the North. The same force there is to the South part, if he needle be rubbed on the South part of the Loadstone. Nor is the force lesse for the East or West part of the Loadstone▪ though the stone cannot turn it self to the Poles of the world, but only the steel needle that is touched with it. But this I have said cannot be understood, but by experience: for if you put a peice of Loadstone upon a peice of Wood swimming in the water, and you apply that side of the Loadstone that looked Southward before it was cut out of the Rock to the side of another Lodstone that looked Southward also, before it was hewen forth, the stone that swims will fly unto the opposite part of the Vessel with water; but if you turn the Northern part of the Loadstone, to the Southern part of another Load∣stone swimming in the water, the Loadstone that swims presently comes and joyns with it, so that th•• both unite by an admirable harmony of nature; though the Wood or the Vessell of water be between. The same will be done, if you put only an iron Needle, thrust through a quil into a Vessell of water, and hold in your hand a peice of a Loadstone, one side of the Loadstone will drive off the needle, the other will draw it. So saith Bodin. What concerns drawing: that the Loadstone doth draw, is maintained of the Aethiopian Loadstone; Plin. l. 36. c. 16. experience hath proved it; Libavius. I, saith he, when I proved this, wiped off all dust from the Load∣stone, and then I scraped away some powder of its own substance, this was laid upon a paper or plank of wood, and the powder scraped from it was laid under it, the Loadstone moved and attracted. The Loadstone draws the Loadstone, by a certain line, because there is a spirit in it like to the other, and nature enclines and is carried to its like, as much as may be. It is as certain, that it draws Iron also. The hardnesse of Iron gives way, and obeys; and that matter which tames all things, runs to I know not what empty thing, and as it comes nearer it stands still, and is held and sticks in imbraceings, Plin. l. 36. c. 26. The vertue of it was found out, when the nails of his shoos and top of his crook stuck fast, for the first inventor was a Heyward. Nor doth it draw Iron on each part with the same force. The rule seems to be a right line. Therefore where the vertue comes not, the ends are turned, and whilst one of them inclines to the needle, the other accidentally turns from it, and seems to reject it. The same reason serves for divers Load∣stones. In the Midland Seas of Sardinia, at the foot of the Moun∣taines that part, they bend Eastward; they say there is a Loadstone that draws Iron, but on the opposite part, one that drives it off, and Page  105 therefore it is called Theamedes, Plin. l. 2. Wherefore do we go to Mountaines? We may see it in every laboratory, if we will be∣leive Libavius, Syntagm, Art. Chymic. Tract. 1. l. 1. c. 19. There are opposite parts in one and the same stone contrary to the rest: and it hath an example of sympathy and antipathy in it self; as Vipers, Scorpions and venemous Creatures have in themselves both their friends and their enemies. I shall set down some examples of at∣traction. Severus Milevitanus saw, when Bathanarius, heretofore governour of Africa, put Silver under between the Stone and the Iron; the Iron on the top moved, and the Silver was in the middle, and suffered nothing but with a most swift retrait, the Man drew the stone downward, and the stone drew the Iron upward. August de civitat. Dei lib. 21. cap. In Alexandria in Aegypt, at the roof of the Temple of Serapus, there was a Loadstone fastned in, which held an Idol that had an Iron in the head so fast, that it hung between the roof and the ground; Euseb in Histor. Eccles. Agricola said, he saw a round look∣ing glasse, that was three hands breadth broad, and two high; in the concave part whereof there was a Loadstone, included above, (Agricola de subter••n) that drew an Iron boul placed at the bottom of the glasse unto it self, so that the thick body of the glasse could not hinder the force of it; the Iron Globe that useth to fall down, was carried up. Let us come to the cause, and inquire whence comes this force in the Loadstone. Each man speaks diversly, and so ma∣ny men allmost so many opinions. Libav. l. 1. de Bitum▪ c. 12, saith that there is a bituminous nature in the Loadstone, reduced to the dis∣position of Iron, by a similitude of sympathy and mixture, where∣by the same principles grow in Iron. And he adds, that there is an Iron bituminous spirit common to them both, but it flows not out continually, and as strong from Iron as from the Loadstone, by reason of the diversity of coagulation or commision; Others attribute that to the hidden forme: Others alleage a mutual harmony of natu∣rall things. There are in the great world, saith Langius, l. 2. Epist. 55, under the concave of the Moon, some things that by a secret consent agree wonderfully together. The truth is, the Loadstone is some kind of vein of Iron, and Iron may be generated of it: Sennert. l. 8. Epit. c. 4. But the Loadstone loseth its attractive force, if you work it in the fire: For whilest it burns, the brimstony spirit of it flyes forth, as Libav. l. 2. singul. thinks. We saw, saith Porta (Mag. natur. l. 7. c. 7.) with great delight, the Loadstone buried in burning Coles, to cast forth a blew brimstony Iron kind of flame, which be∣ing dispersed, the quality of its life departed, and it lost its power to attract. It yields to the injuries of the weather, and dies with old age. The expiring of it, is hindred by oyntments rub'd upon it, and the tenacious juice of Leeks; others add, oyle of Bricks. Lem. l. 4. c. 10. de occult. But Cardanus l. 7. de subtil: denyeth this. It will not lay hold on rusty Iron, and much lesse on rust, Scaliger Exerc. 112. Otherwise if Iron-filings were buried in dust, or the Iron be on the other side of the Table, the spirit, as was said, is not hindred.