CHAP. XXXVIII.
On Cases of Attraction in other Bodies.
ery often the herd of philosophizers and
plagiarists repeat from the records of others in natural philosophy opinions and errors about the attractions of various
bodies; as that Diamond attracts iron, and snatches it away from a magnet; that there are various kinds or magnets, some
which attract gold, others silver, brass, lead; even some which attract flesh, water, fishes. The flame of sulphur is
said to seek iron and stones; so white naphtha is said to attract fire. I have said above that inanimate natural bodies do not attract, and are not attracted by, others on the earth, excepting
magnetically or electrically. Wherefore it is not true that there are magnets which attract gold or other metals; because
a magnetick substance draws nothing but magnetick substances. Though Fracastorio says that he has shown a magnet drawing
silver; if this were true, it must have happened on account of iron skilfully mixed with that silver or concealed in it,
or else because nature (as she does sometimes, but rarely) had mixed iron with the silver; iron indeed is rarely mixed
with silver by nature; silver with iron very rarely or never. Iron is mixed with silver by forgers of false coin or from
the avarice of princes in the coining of money, as was the case with the denarius of Antony189, provided that Pliny is recording a true incident. So Cardan (perhaps deceived by others) says that
there is a certain kind of loadstone which draws silver; he adds a most foolish test of this: "If therefore" (he says) "a
slender rod of silver be steeped in that in which a versatory needle has stood, it will turn toward silver (especially
toward a large quantity) although it be buried; by this means anyone will be able easily to dig up concealed treasures."
He adds that "it should be very good stone, such as he has not yet seen." Nor indeed will either he or anyone else ever
see such a stone or such an experiment. Cardan brings forward an attraction of flesh, wrongly so named and very
dissimilar from that of the loadstone; for his magnes creagus or flesh-magnet, from the experiment that it
sticks to the lips, must be hooted out from the assembly of loadstones, or by all means from the family of things
attractive. Lemnian earth, ruddle, and very many minerals do this, and yet they are fatuously said to attract. He will
have it that there is another loadstone, as it were, a third species, into which, if a needle is driven and afterwards
stuck into the body, it is not felt. But what has attraction to do with stupefaction, or stupor with a Philosopher's
intellect, when he is discoursing about attraction? There are many stones, both found in nature and made by art, which
have the power of stupefying. Sulphur flame is said by some to attract, because it consumes certain metals by its power
of penetration. So white naphtha attracts flame, because it gives off and exhales an inflammable vapour, on which account
it is kindled at some distance, just as the smoke of a recently extinguished candle takes fire again from another flame;
for fire creeps to fire through an inflammable medium. Why the sucking fish Echineis or the Remora should stay ships has
been variously treated by Philosophers, who are often accustomed to fit this fable (as many others) to their theories,
before they find out whether the thing is so in nature. Therefore, in order that they may support and agree with the
fatuities of the ancients, they put forward even the most fatuous ratiocinations and ridiculous problems, cliffs that
attract, where the sucking fish tarry, and the necessity of some vacuum, I know not what, or
how produced. Pliny and Julius Solinus make mention of a stone Chatochitis190.
They say that it attracts flesh, and keeps hold of the hands, just as a loadstone does iron, and amber chaff. But that
happens only from a stickiness and from glue contained in it, since it sticks more easily to the hands when they are
warm. Sagda or Sagdo191, of the colour of a sard, is a precious stone
mentioned by Pliny, Solinus, Albertus, and Evax192; they describe its nature
and relate, on the authority of others, that it specially attracts wood to itself. Some even babble that woods cannot be
wrenched away except they are cut off. Some also narrate that a stone is found which grows pertinaciously into ships, in
the same way as certain testacea on long voyages. But a stone does not draw because it sticks; and if it drew, it would
certainly draw shreds electrically, Encelius saw in the hands of a sailor such a stone of feeble virtue, which would
hardly attract even the smallest twigs; and in truth, not of the colour of the sard. So Diamond, Carbuncle, Crystal, and
others do attract. I pass over other fabulous stones; Pantarbe, about which Philostratus writes that it draws other
stones to itself; Amphitane also, which attracts gold. Pliny in his origin of glass will have it that a loadstone is an
attractor of glass, as well as of iron. For in his method of preparing glass, when he has indicated its nature, he
subjoins this about loadstone. "Soon (such is the astute and resourceful craft) it was not content to have mixed natron;
loadstone also began to be added, since it was thought to attract to itself the liquor of glass (as it does iron)."
Georgius Agricola writes that to the material of glass (sand and natron) one part also of loadstone is added. "Because
that force is believed, in our times just as in former times, to attract the liquor of glass to itself, as it attracts
iron to itself, purges it when drawn, and makes clear glass from green or muddy; but the fire afterwards burns up the
loadstone." It is true indeed that some sort of magnes (as the magnesia of the glass-makers imbued with no
magnetick virtues) is sometimes put in and mixed with the material of the glass; not, however, because it attracts glass.
But when a loadstone is burnt, it does not lay hold of iron at all, nor is iron when red-hot allured by any loadstone;
and loadstone also is burnt up by more powerful fires and loses its attractive potency. Nor is this a function of
loadstone alone in the glass furnaces; but also of certain pyrites and of some easily combustible iron ores, which are
the only ones used by our glass-makers, who make clear, bright glass. They are mixed with the sand, ashes, and natron
(just as they are accustomed to make additions in the case of metallick ores whilst they are smelted), so that when the
material slows down into glass, the green and muddy colour of the glass may be purged by the penetrating heat. For no
other material becomes so hot, or bears the fire for such a convenient time, until the material
of the glass is perfectly fluid, and is at the same time burnt up by that ardent fire. It happens, however, sometimes,
that on account of the magnetick stone, the magnesia, or the ore, or the pyrites, the glass has a dusky colour, when they
resist the fire too much and are not burnt up, or are put in in too great quantity. Wherefore manufacturers are seeking
for a stone suitable for them, and are observing also more diligently the proportion of the mixture. Badly therefore did
the unskilful philosophy of Pliny impose upon Georgius Agricola and the more recent writers, so that they thought the
loadstone was wanted by glass-makers on account of its magnetick strength and attraction. But Scaliger in De
Subtilitate ad Cardanum, in making diamond attract iron, when he is discussing magneticks, wanders far from the
truth, unless it be that diamond attracts iron electrically, as it attracts wood, straws, and all other minute bodies
when it is rubbed. Fallopius reckons that quicksilver draws metals by reason of an occult property, just as a loadstone
iron, amber chaff. But when quicksilver enters metals, it is wrongly called attraction. For metals imbibe quicksilver,
just as clay water; nor do they do this unless they are touching, for quicksilver does not allure gold or lead to itself
from afar, but they remain motionless in their places.