Loadstone

“ The ancients were acquainted with the loadstone, but they only knew that it possessed the power of attracting iron, whether it was that they attached little value to a mere object of curiosity which led to nothing, or whether they had never examined this stone with sufficient care. A single experiment more would have taught them that it turns of itself toward the poles of the earth, and would have put into their hands the invaluable treasure of the mariner’s compass. ”

“ It also draws ores of iron, those that are rich and of iron colour; the poorer and not so productive ores it does not attract, except they be prepared with some art. A loadstone loses some attractive virtue, and, as it were, pines away with age, if exposed too long to the open air instead of being laid in a case with filings or scales of iron. ”

“ Strong loadstones are dug up by themselves, weaker ones too have their own proper vein. Both are found in iron mines. Iron ore most often occurs alone, without strong loadstone (for the more perfect are rarely met with) . Strong loadstone is a stone resembling iron ”

“ Northern parts are attracted by the southern of the earth; so in the boat they tend toward the south. A piece of iron touched by the northern parts of a loadstone becomes south at the one end and tends always (if it is near and within the orbe of the loadstone) to the north of the stone, and if it be free and left to itself at some distance from the stone, it tends to the northern part of the earth. The northern pole A of a loadstone turns to G, the south of the earth; a versorium touched at its cusp by the part A follows A, because it has become southern. ”

“ The following is a literal translation of the curious passage:—
376The Loadstone is a wonderful sort of mineral. Any articles made of iron, like needles, if touched by it, derive by contact not only peculiar power, but a certain property of motion by which they turn ever towards the Constellation of the Bear, near the North Pole. By some peculiar correspondency of impulse, any number of needles, which may have touched the loadstone, preserve at all times a precisely corresponding position and motion. ”

“ As for the Loadstone, it is not more wonderful in attracting Iron, than Beauty, which admirably attracts the Optick Perception of Human Creatures: and who knows, but the North and South Air may be the most proper Air for the Respiration of the Loadstone; and, that Iron may be the most proper Food for it. But, by reason there hath been so many Learned Men puzled in their Opinions concerning the several Effects of the Loadstone, I dare not venture to treat of the Nature, and Natural Effects of that Mineral ”

“ Thus if one had iron nails in one's boots, one could not tear away one's foot on the one mountain, nor stand still on the other. Albertus Magnus writes that a loadstone had been found in his day which with one part drew to itself iron, and repelled it with its other end; but Albertus observed the facts badly; for every loadstone attracts with one end iron that has been touched with a loadstone, and drives it away with the other; and draws iron that been touched with a loadstone more powerfully than iron that has not been so touched. ”

“ Cardan asks why no other metal is attracted by any other stone; because (he replies) no metal is so cold as iron; as if indeed cold were the cause of the attraction, or as if iron were much colder than lead, which neither follows nor is deflected towards a loadstone. But that is a chilly story, and worse than an old woman's tale. So also is the notion that the loadstone is alive and that iron is its food. But how does the loadstone feed on the iron, when the filings in which it is kept are neither consumed nor become lighter? ”

“ For since in a loadstone both verticity and the power disponent have existed through many ages, or from the very beginnings, have been inborn and confirmed, and also the special form of the terrestrial globe cannot easily be changed by another loadstone, as iron is changed; it happens from the constant nature of each, that one has not the sudden power over another of changing its verticity, but that they can only mutually come to agreement with each other. ”

“ Iron ore yields iron in furnaces; loadstone also pours forth iron in the furnaces, but of a much more excellent sort, that which is called steel or blade-edge; and the better sort of iron ore is a weak loadstone, the best loadstone being a most excellent ore of iron, in which, as is to be shown by us, the primary properties are grand and conspicuous. Weaker loadstone or iron ore is that in which these properties are more obscure, feeble, and are scarce perceptible to the senses. ”

“ Loadstone is found either in veins of its own or in iron mines, when the homogeneous substance of the earth, either having or assuming a primary form, is changed or concreted into a stony substance, which besides the primary qualities of its nature has various dissimilitudes and differences in different quarries and mines, as if from different matrices, and very many secondary qualities and varieties in its substance. ”

“ After comparing the properties of the loadstone and of iron, his first step in this induction was that the two materials, found everywhere, [69] are consanguineous: [70] "These two associated bodies possess the true, strict form of one species, though because of the outwardly different aspect and the inequality of the selfsame innate potency, they have hitherto been held to be different ..." Good iron and good loadstone are more similar than a good and a poor loadstone, or a good and a poor iron ore. ”

“ Nor is this onely true in Irons, but in the Loadstone it self. For if a Loadstone be made red hot, it loseth the magnetical vigour it had before in it self, and acquires another from the Earth in its refrigeration; for that part which cooleth toward the Earth will acquire the respect of the North, and attract the Southern point or cuspis of the Needle. The experiment hereof we made in a Loadstone of a parallelogram or long square figure; wherein onely inverting the extreams, as it came out of the fire, we altered the poles or faces thereof at pleasure. ”

“ The better loadstones turn themselves round more quickly toward the poles or points of variation; then they also lead along and turn round more quickly, according to the greater quantity and mass of wood, a boat and other stuff. In a declination instrument, the more powerful force of a loadstone is looked for and required. Those therefore are more lively when they get through their work readily, and pass through and come back again with speed, and swiftly at length settle at their own point. ”

“ So also a very fine dust is insensibly born on a loadstone in some very slight quantity, by which something might have been added to the weight of the loadstone but which is only a surface accretion and might even be wiped off with no great difficulty. Some think that a weak and sluggish stone can bring itself back into better condition, and that a very powerful one also might present it with the highest powers. Do they acquire strength like animals when they eat and are sated? ”

“ 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. ”

“ In the East Indies it is said that a king should have a seat of loadstone at his coronation; probably because the magnetic influence of the stone was supposed to attract power, favor, and gifts to the sovereign. But it is not only in the Orient that magnetite is prized for its talismanic powers, for even in some parts of our own land this belief is still prevalent. Large quantities of loadstone are found at Magnet Cove, Arkansas, and it is estimated that from one to three tons are sold annually to the negroes to be used in the Voodoo ceremonies as conjuring stones. ”

“ Oblong iron rods are both drawn more quickly to a loadstone and cleave to it with greater obstinacy than round or square pieces, for the same reasons which we have proven in the case of the loadstone. ”

“ Iron filings, after being heated for a long time, are attracted by a loadstone, yet not so strongly or from so great a distance as when not heated. A loadstone loses some of its virtue by too great a heat ”

“ This too you should understand, and hold firmly in memory, that as a strong loadstone, and iron touched with the same, do not invariably point exactly to the true pole but to the point of the variation; so does a weaker loadstone, and so does the iron, which directs itself by its own forces only, not by those impressed by the stone ”

“ This iron we term wrought, and its attraction by the loadstone is manifest to all. But we, by more carefully trying everything, have found out that iron merely, by itself alone, not excited by any loadstone, not charged by any alien forces, attracts other iron; though it does not so eagerly snatch and suddenly pluck at it as would a fairly strong loadstone ”

“ For as the one imparts and stirs, so the other conceives, and being stirred remains in virtue, and pours back the forces also by its own activity. But since iron is more like iron than loadstone, and the virtue in both pieces of iron is exalted by the proximity of the loadstone, so in the loadstone itself, in case of equal strength, likeness of substance prevails, and iron gives itself up rather to iron, and they are united by their very similar homogenic powers. ”

“ Tommy inquired the reason of this, and Mr Barlow gave him this additional explanation: "The persons who first discovered the wonderful powers of the loadstone, in communicating its virtues to iron, diverted themselves, as we do now, in touching needles and small pieces of iron, which they made to float upon water, and attracted them about with other pieces of iron. ”

“ Moreover we see that the best loadstone and the ore of iron are both as it were distressed by the same maladies & diseases, both run to old age in the same way & exhibit the same marks of it, are preserved & keep their properties by the same remedies & safeguards ”

“ But amongst all these kinds of invention, that is most likely, wherein a loadstone is so disposed that it shall draw unto it on a reclined plane a bullet of steel, which steel as it ascends near to the loadstone, may be contrived to fall down through some hole in the plane, and so to return unto the place from whence at first it began to move ”

“ Let the iron be the best steel, smoothed, shining, and even. A loadstone with such an appliance, which before only bore four ounces of iron, will now raise twelve. But the greatest force of a combining or rather united nature is seen when two loadstones, armed with iron caps, are so joined by their concurrent (commonly called contrary) ends, that they mutually * attract and raise one another. In this way a weight of twenty ounces is raised, when either stone unarmed would only allure four ounces of iron. Iron unites to an armed loadstone more firmly than to a loadstone ”

“ If a loadstone is rather weak, a versorium hardly turns when a plate is put in between; for the vigour of the rather weak loadstone, being diffused through the extremities, passes less through the * middle. But if the plate has been touched in this way by a pole in the middle and has been removed from the stone outside its orbe of virtue, then you will see the point of the same versorium tend in the contrary direction and desert the centre of the small plate, which formerly it desired; for outside the orbe of virtue it has an opposite verticity, in the vicinity the same ”

“ For the sake of experiment, let there be a rod of iron 4 or * 5 digits long, untouched by a loadstone; as soon as you touch one end only with a loadstone, the opposite end immediately, or in the twinkling of an eye, by the power that it has conceived, repels or attracts a versorium, if it be applied to it ever so quickly. ”

“ He answers, like Descartes, that “the pores of iron have an analogy to the particles of the vortex circulating about the loadstone, which yields them such access as they can find in no other bodies, whose pores are differently formed.”
Certain authors report, that the properties of the loadstone, particularly its tendency towards the north pole, enabled the ancients to undertake long voyages; and they pretend, that the Egyptians, Phœnicians, and Carthaginians, employed the compass to guide them in their naval excursions ”

“ Steer, to direct or guide a vessel in its course.
Destination, the place to which a person is bound.
Practical, capable of practice, not merely speculative.
What is the Loadstone?
An ore of iron which possesses the peculiar property of attracting iron, namely, of drawing it in contact with its own mass, and holding it firmly attached by its own power of attraction. A piece of loadstone drawn several times along a needle, [96] or a small piece of iron, converts it into an artificial magnet ”

“ Your needle, dear Annie, has never been touched by the wonderful stone! You must know that some few hundred years ago, people discovered that a mineral called the loadstone, found in iron mines, had the quality of always pointing to the North, and they found, too, that any iron rubbed with it would possess the same quality. The needle Tom tells us of has undergone this operation. Before the invention of the compass, it was only by watching the stars that sailors could direct their course by night. ”