Chap. xvi.
That loadstone & iron ore are the same, but iron an extract from both, as other metals are from their own ores; & that all magnetick virtues, though weaker, exist in the ore itself & in smelted iron.

H itherto we have declared the nature & powers of the loadstone, & also the properties & essence of iron; it now remains to show their mutual affinities, & kinship, so to speak, & how very closely conjoined these substances are. At the highest part of the terrestrial globe, or at its perishable surface & rind, as it were, these two bodies usually originate & are produced in one and the same matrix, as twins in one mine. 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; out of it is usually smelted the finest iron, which the Greeks call stomoma, the Latins acies, the Barbarians (not amiss) aciare, or aciarium. This same stone draws, repels, controls other loadstones, directs itself to the poles of the world, picks up smelted iron, and works many other wonders, some already set forth by us, but many more which we must demonstrate more fully. A weaker loadstone, however, will exhibit all these powers, but in a lesser degree; while iron ore, & also wrought iron (if they have been prepared) show their strength in all magnetick experiments not less than do feeble and weak loadstones; & an inert piece of ore, & one possessed of no magnetick properties, & just thrown out98 of the pit, when roasted in the fire & prepared with due art (by the elimination of humours & foreign excretions) awakes, and becomes in power & potency a magnet, occasionally a stone or iron ore is mined, which attracts forthwith without being prepared: for native iron of the right colour attracts and governs iron magnetically. One form then belongs to the one mineral, one species, one self-same essence. For to me there seems to be a greater difference, & unlikeness, between the strongest loadstone, & a weak one which scarce can attract a single chip of iron; between one that is stout, strong, metallick, & one that is soft, friable, clayey; amidst such variety of colour, substance, quality, & weight; than there is on the one hand between the best ore, rich in iron, or iron that is metallick from the beginning, and on the other the most excellent loadstone. Usually, too, there are no marks to distinguish them, and even metallurgists cannot decide between them, because they agree together in all respects. 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; & yet again the one increases the potency of the other, & by artfully devised adjuncts marvellously intensifies, & exalts it. For both are impaired by the more acrid juices as by poisons, & the aqua fortis of the Chemists inflicts on both the same wounds, and when exposed too long to harm from the atmosphere, they both alike pine away, so to speak, & grow old; each is preserved by being kept in the dust & scrapings of the other; & when a fit piece of steel or iron is adjoined above its pole, the loadstone's vigour is augmented through the firm union. The loadstone is laid up in iron filings, not that iron is its food; as though loadstone were alive and needed feeding, as Cardan philosophizes99; nor yet that so it is delivered from the inclemency of the weather (for which cause it as well as iron is laid up in bran by Scaliger; mistakenly, however, for they are not preserved well in this way, and keep for years their own fixed forms): nor yet, since they remain perfect by the mutual action of their powders, do their extremities waste away, but are cherished & preserved, like by like. For just as in their own places, in the mines, bodies like to each other endure for many ages entire and uncorrupt, when surrounded by bodies of the same stuff, as the lesser interior parts in a great mass: so loadstone and ore of iron, when inclosed in a mound of the same material, do not exhale their native humour, do not waste away, but retain their soundness. A loadstone lasts longer in filings of smelted iron, & a piece of iron ore excellently also in dust of loadstone; as also smelted iron in filings of loadstone & even in those of iron. Then both these allied bodies have a true & just form of one & the same species; a form which until this day was cons............