A man may sometimes set aside
meditations about eternal things, and for recreation turn to
consider the truths of generation which are probable only; he
will thus gain a pleasure not to be repented of, and secure for
himself while he lives a wise and moderate pastime. Let us grant
ourselves this indulgence, and go through the probabilities
relating to the same subjects which follow next in order.
Water which is mingled with fire, so much as is fine and
liquid (being so called by reason of its motion and the way in
which it rolls along the ground), and soft, because its bases
give way are less stable than those of earth, when separated from
fire and air and isolated, becomes more uniform, and by their
retirement is compressed into itself; and if the condensation be
very great, the water above the earth becomes hail, but on the
earth, ice; and that which is congealed in a less degree and is
only half solid, when above the earth is called snow, and when
upon the earth, and condensed from dew, hoarfrost. Then, again,
there are the numerous kinds of water which have been mingled
with one another, and are distilled through plants which grow in
the earth; and this whole class is called by the name of juices
or saps. The unequal admixture of these fluids creates a variety
of species; most of them are nameless, but four which are of a
fiery nature are clearly distinguished and have names. First
there is wine, which warms the soul as well as the body:
secondly, there is the oily nature, which is smooth and divides
the visual ray, and for this reason is bright and shining and of
a glistening appearance, including pitch, the juice of the castor
berry, oil itself, and other things of a like kind: thirdly,
there is the class of substances which expand the contracted
parts of the mouth, until they return to their natural state, and
by reason of this property create sweetness;-these are included
under the general name of honey: and, lastly, there is a frothy
nature, which differs from all juices, having a burning quality
which dissolves the flesh; it is called opos (a vegetable acid).
As to the kinds of earth, that which is filtered through water
passes into stone in the following manner:-The water which mixes
with the earth and is broken up in the process changes into air,
and taking this form mounts into its own place. But as there is
no surrounding vacuum it thrusts away the neighbouring air, and
this being rendered heavy, and, when it is displaced, having been
poured around the mass of earth, forcibly compresses it and
drives it into the vacant space whence the new air had come up;
and the earth when compressed by the air into an indissoluble
union with water becomes rock. The fairer sort is that which is
made up of equal and similar parts and is transparent; that which
has the opposite qualities is inferior. But when all the watery
part is suddenly drawn out by fire, a more brittle substance is
formed, to which we give the name of pottery. Sometimes also
moisture may remain, and the earth which has been fused by fire
becomes, when cool, a certain stone of a black colour. A like
separation of the water which had been copiously mingled with
them may occur in two substances composed of finer particles of
earth and of a briny nature; out of either of them a half solid
body is then formed, soluble in water-the one, soda, which is
used for purging away oil and earth, and other, salt, which
harmonizes so well in combinations pleasing to the palate, and
is, as the law testifies, a substance dear to the gods. The
compounds of earth and water are not soluble by water, but by
fire only, and for this reason:-Neither fire nor air melt masses
of earth; for their particles, being smaller than the interstices
in its structure, have plenty of room to move without forcing
their way, and so they leave the earth unmelted and undissolved;
but particles of water, which are larger, force a passage, and
dissolve and melt the earth. Wherefore earth when not
consolidated by force is dissolved by water only; when
consolidated, by nothing but fire; for this is the only body
which can find an entrance. The cohesion of water again, when
very strong, is dissolved by fire only-when weaker, then either
by air or fire-the former entering the interstices, and the
latter penetrating even the triangles. But nothing can dissolve
air, when strongly condensed, which does not reach the elements
or triangles; or if not strongly condensed, then only fire can
dissolve it. As to bodies composed of earth and water, while the
water occupies the vacant interstices of the earth in them which
are compressed by force, the particles of water which approach
them from without, finding no entrance, flow around the entire
mass and leave it undissolved; but the particles of fire,
entering into the interstices of the water, do to the water what
water does to earth and fire to air, and are the sole causes of
the compound body of earth and water liquefying and becoming
fluid. Now these bodies are of two kinds; some of them, such as
glass and the fusible sort of stones, have less water than they
have earth; on the other hand, substances of the nature of wax
and incense have more of water entering into their composition.
I have thus shown the various classes of bodies as they are
diversified by their forms and combinations and changes into one
another, and now I must endeavour to set forth their affections
and the causes of them. In the first place, the bodies which I
have been describing are necessarily objects of sense. But we
have not yet considered the origin of flesh, or what belongs to
flesh, or of that part of the soul which is mortal.
