CHAP. XXVI.

Why there should appear to be a greater love between

_iron and loadstone, than between loadstone and loadstone, or_

between iron and iron, when close to the loadstone,

_within its orbe of virtue._

Magnet attracts magnet, not in every part and on every side with equal

conditions, as iron, but at one and a fixed point; therefore the poles of

both must be exactly disposed, otherwise they do not cleave together duly

and strongly. But this disposition is not easy and expeditious; wherefore a

loadstone seems not to conform to a loadstone, when nevertheless they agree

very well together. A piece of iron by the sudden impression of a loadstone

is not only allured by the stone, but is renewed, its forces being drawn

forth; by which it follows and solicits the loadstone with no less impulse,

and even leads another piece of iron captive. Let there be a small iron

spike above a loadstone clinging firmly to it; if you apply an unmagnetized

rod of iron to the spike, not, however, {95} so that it touches the stone,

you will see the spike when it has touched the iron, leaving the loadstone,

follow the rod, try to grasp it by leaning toward it, and (if it should

touch it) cleave firmly to it: for a piece of iron, when united and joined

to another piece of iron placed within the orbe of virtue of the loadstone,

draws it more strongly than does the loadstone itself. The natural

magnetick virtue, confused and dormant in the iron, is aroused by the

loadstone, is linked to the loadstone, and rejoices with it in its primary

form; then smelted iron becomes a perfect magnetick, as robust as the

loadstone itself. 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. Which thing happens not so

much from a coition, as from a firmer unition; and a knob or snout of

steel, fixed skilfully on the pole of the stone, raises greater weights of

iron than the stone of itself could. When steel or iron is smelted from

loadstone or iron ore, the slag and corrupt substances are separated from

the better by the fusion of the material; whence (in very large measure)

that iron contains the nature of the earth, purified from alien flaw and

blemish, and more homogenic and perfect, though deformed by the fusion. And

when that material indeed is provoked by a loadstone, it conceives the

magnetick virtues, and within their orbe is raised in strength more than

the weaker loadstone, which with us is often not free from some admixture

of impurities.

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On the magnet, magnetick bodies also, and on the great magnet the earth a new physiology, demonstrated by many arguments & experiments · 第 45 / 110 题