r antecedent in
the course of the generation of metals. The earth emits various humours,
not begotten of water nor of dry earth, nor from mixtures of these, but
from the substance of the earth itself: these humours are not distinguished
by contrary qualities or substance, nor is the earth a simple substance, as
the Peripateticks dream. The humours proceed from vapours sublimated from
great depths; all waters are extracts and, as it were, exudations from the
earth. Rightly then in some measure does Aristotle make out the matter of
metals to be that exhalation which in continuance thickens in the lodes of
certain soils: for the vapours are condensed in places which are less hot
than the spot whence they issued, and by help of the nature of the soils
and mountains, as in a womb, they are at fitting seasons congealed and
changed into metals: but it is not they alone which form ores, but they
flow into and enter a more solid material, and so form metals. So when this
concreted matter has settled down in more temperate beds, it begins to take
shape in those tepid places, just as seed in the warm womb, or as the
embryo acquires growth: sometimes the vapour conjoins with suitable matter
alone: hence some metals are occasionally though rarely dug up native, and
come into existence perfect without smelting: but other vapours which are
mixed with alien soils require smelting in the way that the ores of all
metals are treated, which are rid of all their dross by the force of fires,
and being fused flow out metallick, and are separated from earthy
impurities but not from the true substance of the earth. But in so far as
that it becomes gold, or silver, or copper, or any other of the existing
metals, this does not happen from the quantity or proportion of material,
nor from any forces of matter, as the Chemists fondly imagine; but when the
beds and region concur fitly with the material, the metals assume forms
from the universal nature by which they are perfected; in the same manner
as all the other minerals, plants, and animals whatever: otherwise the
species of metals would be vague and undefined, which are even now turned
up in such scanty numbers that scarce ten kinds are known. Why, however,
nature has been so stingy as regards the number of metals, or why there
should be as many as are known to man, it is not easy to explain; though
the simple-minded and raving Astrologers refer the metals each to its own
planet. But there is no a