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Title: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:34:46 pm
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Meteorology
By Aristotle


Translated by E. W. Webster

----------------------------------------------------------------------

BOOK I

Part 1

We have already discussed the first causes of nature, and all natural
motion, also the stars ordered in the motion of the heavens, and the
physical element-enumerating and specifying them and showing how they
change into one another-and becoming and perishing in general. There
remains for consideration a part of this inquiry which all our predecessors
called meteorology. It is concerned with events that are natural,
though their order is less perfect than that of the first of the elements
of bodies. They take place in the region nearest to the motion of
the stars. Such are the milky way, and comets, and the movements of
meteors. It studies also all the affections we may call common to
air and water, and the kinds and parts of the earth and the affections
of its parts. These throw light on the causes of winds and earthquakes
and all the consequences the motions of these kinds and parts involve.
Of these things some puzzle us, while others admit of explanation
in some degree. Further, the inquiry is concerned with the falling
of thunderbolts and with whirlwinds and fire-winds, and further, the
recurrent affections produced in these same bodies by concretion.
When the inquiry into these matters is concluded let us consider what
account we can give, in accordance with the method we have followed,
of animals and plants, both generally and in detail. When that has
been done we may say that the whole of our original undertaking will
have been carried out.

After this introduction let us begin by discussing our immediate subject.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:36:07 pm
Part 2

We have already laid down that there is one physical element which
makes up the system of the bodies that move in a circle, and besides
this four bodies owing their existence to the four principles, the
motion of these latter bodies being of two kinds: either from the
centre or to the centre. These four bodies are fire, air, water, earth.
Fire occupies the highest place among them all, earth the lowest,
and two elements correspond to these in their relation to one another,
air being nearest to fire, water to earth. The whole world surrounding
the earth, then, the affections of which are our subject, is made
up of these bodies. This world necessarily has a certain continuity
with the upper motions: consequently all its power and order is derived
from them. (For the originating principle of all motion is the first
cause. Besides, that clement is eternal and its motion has no limit
in space, but is always complete; whereas all these other bodies have
separate regions which limit one another.) So we must treat fire and
earth and the elements like them as the material causes of the events
in this world (meaning by material what is subject and is affected),
but must assign causality in the sense of the originating principle
of motion to the influence of the eternally moving bodies.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:36:32 pm
Part 3

Let us first recall our original principles and the distinctions already
drawn and then explain the 'milky way' and comets and the other phenomena
akin to these.

Fire, air, water, earth, we assert, originate from one another, and
each of them exists potentially in each, as all things do that can
be resolved into a common and ultimate substrate.

The first difficulty is raised by what is called the air. What are
we to take its nature to be in the world surrounding the earth? And
what is its position relatively to the other physical elements. (For
there is no question as to the relation of the bulk of the earth to
the size of the bodies which exist around it, since astronomical demonstrations
have by this time proved to us that it is actually far smaller than
some individual stars. As for the water, it is not observed to exist
collectively and separately, nor can it do so apart from that volume
of it which has its seat about the earth: the sea, that is, and rivers,
which we can see, and any subterranean water that may be hidden from
our observation.) The question is really about that which lies between
the earth and the nearest stars. Are we to consider it to be one kind
of body or more than one? And if more than one, how many are there
and what are the bounds of their regions?


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:36:51 pm
We have already described and characterized the first element, and
explained that the whole world of the upper motions is full of that
body.

This is an opinion we are not alone in holding: it appears to be an
old assumption and one which men have held in the past, for the word
ether has long been used to denote that element. Anaxagoras, it is
true, seems to me to think that the word means the same as fire. For
he thought that the upper regions were full of fire, and that men
referred to those regions when they spoke of ether. In the latter
point he was right, for men seem to have assumed that a body that
was eternally in motion was also divine in nature; and, as such a
body was different from any of the terrestrial elements, they determined
to call it 'ether'.

For the um opinions appear in cycles among men not once nor twice,
but infinitely often.

Now there are some who maintain that not only the bodies in motion
but that which contains them is pure fire, and the interval between
the earth and the stars air: but if they had considered what is now
satisfactorily established by mathematics, they might have given up
this puerile opinion. For it is altogether childish to suppose that
the moving bodies are all of them of a small size, because they so
to us, looking at them from the earth.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:37:05 pm
This a matter which we have already discussed in our treatment of
the upper region, but we may return to the point now.

If the intervals were full of fire and the bodies consisted of fire
every one of the other elements would long ago have vanished.

However, they cannot simply be said to be full of air either; for
even if there were two elements to fill the space between the earth
and the heavens, the air would far exceed the quantitu required to
maintain its proper proportion to the other elements. For the bulk
of the earth (which includes the whole volume of water) is infinitesimal
in comparison with the whole world that surrounds it. Now we find
that the excess in volume is not proportionately great where water
dissolves into air or air into fire. Whereas the proportion between
any given small quantity of water and the air that is generated from
it ought to hold good between the total amount of air and the total
amount of water. Nor does it make any difference if any one denies
that the elements originate from one another, but asserts that they
are equal in power. For on this view it is certain amounts of each
that are equal in power, just as would be the case if they actually
originated from one another.

So it is clear that neither air nor fire alone fills the intermediate
space.

It remains to explain, after a preliminary discussion of difficulties,
the relation of the two elements air and fire to the position of the
first element, and the reason why the stars in the upper region impart
heat to the earth and its neighbourhood. Let us first treat of the
air, as we proposed, and then go on to these questions.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:37:19 pm
Since water is generated from air, and air from water, why are clouds
not formed in the upper air? They ought to form there the more, the
further from the earth and the colder that region is. For it is neither
appreciably near to the heat of the stars, nor to the rays relected
from the earth. It is these that dissolve any formation by their heat
and so prevent clouds from forming near the earth. For clouds gather
at the point where the reflected rays disperse in the infinity of
space and are lost. To explain this we must suppose either that it
is not all air which water is generated, or, if it is produced from
all air alike, that what immediately surrounds the earth is not mere
air, but a sort of vapour, and that its vaporous nature is the reason
why it condenses back to water again. But if the whole of that vast
region is vapour, the amount of air and of water will be disproportionately
great. For the spaces left by the heavenly bodies must be filled by
some element. This cannot be fire, for then all the rest would have
been dried up. Consequently, what fills it must be air and the water
that surrounds the whole earth-vapour being water dissolved.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:37:40 pm
After this exposition of the difficulties involved, let us go on to
lay down the truth, with a view at once to what follows and to what
has already been said. The upper region as far as the moon we affirm
to consist of a body distinct both from fire and from air, but varying
degree of purity and in kind, especially towards its limit on the
side of the air, and of the world surrounding the earth. Now the circular
motion of the first element and of the bodies it contains dissolves,
and inflames by its motion, whatever part of the lower world is nearest
to it, and so generates heat. From another point of view we may look
at the motion as follows. The body that lies below the circular motion
of the heavens is, in a sort, matter, and is potentially hot, cold,
dry, moist, and possessed of whatever other qualities are derived
from these. But it actually acquires or retains one of these in virtue
of motion or rest, the cause and principle of which has already been
explained. So at the centre and round it we get earth and water, the
heaviest and coldest elements, by themselves; round them and contiguous
with them, air and what we commonly call fire. It is not really fire,
for fire is an excess of heat and a sort of ebullition; but in reality,
of what we call air, the part surrounding the earth is moist and warm,
because it contains both vapour and a dry exhalation from the earth.
But the next part, above that, is warm and dry. For vapour is naturally
moist and cold, but the exhalation warm and dry; and vapour is potentially
like water, the exhalation potentially like fire. So we must take
the reason why clouds are not formed in the upper region to be this:
that it is filled not with mere air but rather with a sort of fire.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:37:47 pm
However, it may well be that the formation of clouds in that upper
region is also prevented by the circular motion. For the air round
the earth is necessarily all of it in motion, except that which is
cut off inside the circumference which makes the earth a complete
sphere. In the case of winds it is actually observable that they originate
in marshy districts of the earth; and they do not seem to blow above
the level of the highest mountains. It is the revolution of the heaven
which carries the air with it and causes its circular motion, fire
being continuous with the upper element and air with fire. Thus its
motion is a second reason why that air is not condensed into water.

But whenever a particle of air grows heavy, the warmth in it is squeezed
out into the upper region and it sinks, and other particles in turn
are carried up together with the fiery exhalation. Thus the one region
is always full of air and the other of fire, and each of them is perpetually
in a state of change.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:38:03 pm
So much to explain why clouds are not formed and why the air is not
condensed into water, and what account must be given of the space
between the stars and the earth, and what is the body that fills it.

As for the heat derived from the sun, the right place for a special
and scientific account of it is in the treatise about sense, since
heat is an affection of sense, but we may now explain how it can be
produced by the heavenly bodies which are not themselves hot.

We see that motion is able to dissolve and inflame the air; indeed,
moving bodies are often actually found to melt. Now the sun's motion
alone is sufficient to account for the origin of terrestrial warmth
and heat. For a motion that is to have this effect must be rapid and
near, and that of the stars is rapid but distant, while that of the
moon is near but slow, whereas the sun's motion combines both conditions
in a sufficient degree. That most heat should be generated where the
sun is present is easy to understand if we consider the analogy of
terrestrial phenomena, for here, too, it is the air that is nearest
to a thing in rapid motion which is heated most. This is just what
we should expect, as it is the nearest air that is most dissolved
by the motion of a solid body.

This then is one reason why heat reaches our world. Another is that
the fire surrounding the air is often scattered by the motion of the
heavens and driven downwards in spite of itself.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:38:15 pm
Shooting-stars further suffix to prove that the celestial sphere is
not hot or fiery: for they do not occur in that upper region but below:
yet the more and the faster a thing moves, the more apt it is to take
fire. Besides, the sun, which most of all the stars is considered
to be hot, is really white and not fiery in colour.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:38:29 pm
Part 4

Having determined these principles let us explain the cause of the
appearance in the sky of burning flames and of shooting-stars, and
of 'torches', and 'goats', as some people call them. All these phenomena
are one and the same thing, and are due to the same cause, the difference
between them being one of degree.

The explanation of these and many other phenomena is this. When the
sun warms the earth the evaporation which takes place is necessarily
of two kinds, not of one only as some think. One kind is rather of
the nature of vapour, the other of the nature of a windy exhalation.
That which rises from the moisture contained in the earth and on its
surface is vapour, while that rising from the earth itself, which
is dry, is like smoke. Of these the windy exhalation, being warm,
rises above the moister vapour, which is heavy and sinks below the
other. Hence the world surrounding the earth is ordered as follows.
First below the circular motion comes the warm and dry element, which
we call fire, for there is no word fully adequate to every state of
the fumid evaporation: but we must use this terminology since this
element is the most inflammable of all bodies. Below this comes air.
We must think of what we just called fire as being spread round the
terrestrial sphere on the outside like a kind of fuel, so that a little
motion often makes it burst into flame just as smoke does: for flame
is the ebullition of a dry exhalation. So whenever the circular motion
stirs this stuff up in any way, it catches fire at the point at which
it is most inflammable. The result differs according to the disposition
and quantity of the combustible material. If this is broad and long,
we often see a flame burning as in a field of stubble: if it burns
lengthwise only, we see what are called 'torches' and 'goats' and
shooting-stars. Now when the inflammable material is longer than it
is broad sometimes it seems to throw off sparks as it burns. (This
happens because matter catches fire at the sides in small portions
but continuously with the main body.) Then it is called a 'goat'.
When this does not happen it is a 'torch'. But if the whole length
of the exhalation is scattered in small parts and in many directions
and in breadth and depth alike, we get what are called shooting-stars.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:38:44 pm
The cause of these shooting-stars is sometimes the motion which ignites
the exhalation. At other times the air is condensed by cold and squeezes
out and ejects the hot element; making their motion look more like
that of a thing thrown than like a running fire. For the question
might be raised whether the 'shooting' of a 'star' is the same thing
as when you put an exhalation below a lamp and it lights the lower
lamp from the flame above. For here too the flame passes wonderfully
quickly and looks like a thing thrown, and not as if one thing after
another caught fire. Or is a 'star' when it 'shoots' a single body
that is thrown? Apparently both cases occur: sometimes it is like
the flame from the lamp and sometimes bodies are projected by being
squeezed out (like fruit stones from one's fingers) and so are seen
to fall into the sea and on the dry land, both by night and by day
when the sky is clear. They are thrown downwards because the condensation
which propels them inclines downwards. Thunderbolts fall downwards
for the same reason: their origin is never combustion but ejection
under pressure, since naturally all heat tends upwards.

When the phenomenon is formed in the upper region it is due to the
combustion of the exhalation. When it takes place at a lower level
it is due to the ejection of the exhalation by the condensing and
cooling of the moister evaporation: for this latter as it condenses
and inclines downward contracts, and thrusts out the hot element and
causes it to be thrown downwards. The motion is upwards or downwards
or sideways according to the way in which the evaporation lies, and
its disposition in respect of breadth and depth. In most cases the
direction is sideways because two motions are involved, a compulsory
motion downwards and a natural motion upwards, and under these circumstances
an object always moves obliquely. Hence the motion of 'shooting-stars'
is generally oblique.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:38:58 pm
So the material cause of all these phenomena is the exhalation, the
efficient cause sometimes the upper motion, sometimes the contraction
and condensation of the air. Further, all these things happen below
the moon. This is shown by their apparent speed, which is equal to
that of things thrown by us; for it is because they are close to us,
that these latter seem far to exceed in speed the stars, the sun,
and the moon.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:39:13 pm
Part 5

Sometimes on a fine night we see a variety of appearances that form
in the sky: 'chasms' for instance and 'trenches' and blood-red colours.
These, too, have the same cause. For we have seen that the upper air
condenses into an inflammable condition and that the combustion sometimes
takes on the appearance of a burning flame, sometimes that of moving
torches and stars. So it is not surprising that this same air when
condensing should assume a variety of colours. For a weak light shining
through a dense air, and the air when it acts as a mirror, will cause
all kinds of colours to appear, but especially crimson and purple.
For these colours generally appear when fire-colour and white are
combined by superposition. Thus on a hot day, or through a smoky,
medium, the stars when they rise and set look crimson. The light will
also create colours by reflection when the mirror is such as to reflect
colour only and not shape.

These appearances do not persist long, because the condensation of
the air is transient.

'Chasms' get their appearance of depth from light breaking out of
a dark blue or black mass of air. When the process of condensation
goes further in such a case we often find 'torches' ejected. When
the 'chasm' contracts it presents the appearance of a 'trench'.

In general, white in contrast with black creates a variety of colours;
like flame, for instance, through a medium of smoke. But by day the
sun obscures them, and, with the exception of crimson, the colours
are not seen at night because they are dark.

These then must be taken to be the causes of 'shooting-stars' and
the phenomena of combustion and also of the other transient appearances
of this kind.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:39:26 pm
Part 6

Let us go on to explain the nature of comets and the 'milky way',
after a preliminary discussion of the views of others.

Anaxagoras and Democritus declare that comets are a conjunction of
the planets approaching one another and so appearing to touch one
another.

Some of the Italians called Pythagoreans say that the comet is one
of the planets, but that it appears at great intervals of time and
only rises a little above the horizon. This is the case with Mercury
too; because it only rises a little above the horizon it often fails
to be seen and consequently appears at great intervals of time.

A view like theirs was also expressed by Hippocrates of Chios and
his pupil Aeschylus. Only they say that the tail does not belong to
the comet iself, but is occasionally assumed by it on its course in
certain situations, when our sight is reflected to the sun from the
moisture attracted by the comet. It appears at greater intervals than
the other stars because it is slowest to get clear of the sun and
has been left behind by the sun to the extent of the whole of its
circle before it reappears at the same point. It gets clear of the
sun both towards the north and towards the south. In the space between
the tropics it does not draw water to itself because that region is
dried up by the sun on its course. When it moves towards the south
it has no lack of the necessary moisture, but because the segment
of its circle which is above the horizon is small, and that below
it many times as large, it is impossible for the sun to be reflected
to our sight, either when it approaches the southern tropic, or at
the summer solstice. Hence in these regions it does not develop a
tail at all. But when it is visible in the north it assumes a tail
because the arc above the horizon is large and that below it small.
For under these circumstances there is nothing to prevent our vision
from being reflected to the sun.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:39:42 pm
These views involve impossibilities, some of which are common to all
of them, while others are peculiar to some only.

This is the case, first, with those who say that the comet is one
of the planets. For all the planets appear in the circle of the zodiac,
whereas many comets have been seen outside that circle. Again more
comets than one have often appeared simultaneously. Besides, if their
tail is due to reflection, as Aeschylus and Hippocrates say, this
planet ought sometimes to be visible without a tail since, as they
it does not possess a tail in every place in which it appears. But,
as a matter of fact, no planet has been observed besides the five.
And all of them are often visible above the horizon together at the
same time. Further, comets are often found to appear, as well when
all the planets are visible as when some are not, but are obscured
by the neighbourhood of the sun. Moreover the statement that a comet
only appears in the north, with the sun at the summer solstice, is
not true either. The great comet which appeared at the time of the
earthquake in Achaea and the tidal wave rose due west; and many have
been known to appear in the south. Again in the archonship of Euclees,
son of Molon, at Athens there appeared a comet in the north in the
month Gamelion, the sun being about the winter solstice. Yet they
themselves admit that reflection over so great a space is an impossibility.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:39:56 pm
An objection that tells equally against those who hold this theory
and those who say that comets are a coalescence of the planets is,
first, the fact that some of the fixed stars too get a tail. For this
we must not only accept the authority of the Egyptians who assert
it, but we have ourselves observed the fact. For a star in the thigh
of the Dog had a tail, though a faint one. If you fixed your sight
on it its light was dim, but if you just glanced at it, it appeared
brighter. Besides, all the comets that have been seen in our day have
vanished without setting, gradually fading away above the horizon;
and they have not left behind them either one or more stars. For instance
the great comet we mentioned before appeared to the west in winter
in frosty weather when the sky was clear, in the archonship of Asteius.
On the first day it set before the sun and was then not seen. On the
next day it was seen, being ever so little behind the sun and immediately
setting. But its light extended over a third part of the sky like
a leap, so that people called it a 'path'. This comet receded as far
as Orion's belt and there dissolved. Democritus however, insists upon
the truth of his view and affirms that certain stars have been seen
when comets dissolve. But on his theory this ought not to occur occasionally
but always. Besides, the Egyptians affirm that conjunctions of the
planets with one another, and with the fixed stars, take place, and
we have ourselves observed Jupiter coinciding with one of the stars
in the Twins and hiding it, and yet no comet was formed. Further,
we can also give a rational proof of our point. It is true that some
stars seem to be bigger than others, yet each one by itself looks
indivisible. Consequently, just as, if they really had been indivisible,
their conjunction could not have created any greater magnitude, so
now that they are not in fact indivisible but look as if they were,
their conjunction will not make them look any bigger.

Enough has been said, without further argument, to show that the causes
brought forward to explain comets are false.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:40:06 pm
Part 7

We consider a satisfactory explanation of phenomena inaccessible to
observation to have been given when our account of them is free from
impossibilities. The observations before us suggest the following
account of the phenomena we are now considering. We know that the
dry and warm exhalation is the outermost part of the terrestrial world
which falls below the circular motion. It, and a great part of the
air that is continuous with it below, is carried round the earth by
the motion of the circular revolution. In the course of this motion
it often ignites wherever it may happen to be of the right consistency,
and this we maintain to be the cause of the 'shooting' of scattered
'stars'. We may say, then, that a comet is formed when the upper motion
introduces into a gathering of this kind a fiery principle not of
such excessive strength as to burn up much of the material quickly,
nor so weak as soon to be extinguished, but stronger and capable of
burning up much material, and when exhalation of the right consistency
rises from below and meets it. The kind of comet varies according
to the shape which the exhalation happens to take. If it is diffused
equally on every side the star is said to be fringed, if it stretches
out in one direction it is called bearded. We have seen that when
a fiery principle of this kind moves we seem to have a shooting-star:
similarly when it stands still we seem to have a star standing still.
We may compare these phenomena to a heap or mass of chaff into which
a torch is thrust, or a spark thrown. That is what a shooting-star
is like. The fuel is so inflammable that the fire runs through it
quickly in a line. Now if this fire were to persist instead of running
through the fuel and perishing away, its course through the fuel would
stop at the point where the latter was densest, and then the whole
might begin to move. Such is a comet-like a shooting-star that contains
its beginning and end in itself.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:40:18 pm
When the matter begins to gather in the lower region independently
the comet appears by itself. But when the exhalation is constituted
by one of the fixed stars or the planets, owing to their motion, one
of them becomes a comet. The fringe is not close to the stars themselves.
Just as haloes appear to follow the sun and the moon as they move,
and encircle them, when the air is dense enough for them to form along
under the sun's course, so too the fringe. It stands in the relation
of a halo to the stars, except that the colour of the halo is due
to reflection, whereas in the case of comets the colour is something
that appears actually on them.

Now when this matter gathers in relation to a star the comet necessarily
appears to follow the same course as the star. But when the comet
is formed independently it falls behind the motion of the universe,
like the rest of the terrestrial world. It is this fact, that a comet
often forms independently, indeed oftener than round one of the regular
stars, that makes it impossible to maintain that a comet is a sort
of reflection, not indeed, as Hippocrates and his school say, to the
sun, but to the very star it is alleged to accompany-in fact, a kind
of halo in the pure fuel of fire.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:40:30 pm
As for the halo we shall explain its cause later.
The fact that comets when frequent foreshadow wind and drought must
be taken as an indication of their fiery constitution. For their origin
is plainly due to the plentiful supply of that secretion. Hence the
air is necessarily drier and the moist evaporation is so dissolved
and dissipated by the quantity of the hot exhalation as not readily
to condense into water.-But this phenomenon too shall be explained
more clearly later when the time comes to speak of the winds.-So when
there are many comets and they are dense, it is as we say, and the
years are clearly dry and windy. When they are fewer and fainter this
effect does not appear in the same degree, though as a rule the is
found to be excessive either in duration or strength. For instance
when the stone at Aegospotami fell out of the air-it had been carried
up by a wind and fell down in the daytime-then too a comet happened
to have appeared in the west. And at the time of the great comet the
winter was dry and north winds prevailed, and the wave was due to
an opposition of winds. For in the gulf a north wind blew and outside
it a violent south wind. Again in the archonship of Nicomachus a comet
appeared for a few days about the equinoctial circle (this one had
not risen in the west), and simultaneously with it there happened
the storm at Corinth.

That there are few comets and that they appear rarely and outside
the tropic circles more than within them is due to the motion of the
sun and the stars. For this motion does not only cause the hot principle
to be secreted but also dissolves it when it is gathering. But the
chief reason is that most of this stuff collects in the region of
the milky way.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:41:17 pm
Part 8

Let us now explain the origin, cause, and nature of the milky way.
And here too let us begin by discussing the statements of others on
the subject.

(1) Of the so-called Pythagoreans some say that this is the path of
one of the stars that fell from heaven at the time of Phaethon's downfall.
Others say that the sun used once to move in this circle and that
this region was scorched or met with some other affection of this
kind, because of the sun and its motion.

But it is absurd not to see that if this were the reason the circle
of the Zodiac ought to be affected in the same way, and indeed more
so than that of the milky way, since not the sun only but all the
planets move in it. We can see the whole of this circle (half of it
being visible at any time of the night), but it shows no signs of
any such affection except where a part of it touches the circle of
the milky way.

(2) Anaxagoras, Democritus, and their schools say that the milky way
is the light of certain stars. For, they say, when the sun passes
below the earth some of the stars are hidden from it. Now the light
of those on which the sun shines is invisible, being obscured by the
of the sun. But the milky way is the peculiar light of those stars
which are shaded by the earth from the sun's rays.

This, too, is obviously impossible. The milky way is always unchanged
and among the same constellations (for it is clearly a greatest circle),
whereas, since the sun does not remain in the same place, what is
hidden from it differs at different times. Consequently with the change
of the sun's position the milky way ought to change its position too:
but we find that this does not happen. Besides, if astronomical demonstrations
are correct and the size of the sun is greater than that of the earth
and the distance of the stars from the earth many times greater than
that of the sun (just as the sun is further from the earth than the
moon), then the cone made by the rays of the sun would terminate at
no great distance from the earth, and the shadow of the earth (what
we call night) would not reach the stars. On the contrary, the sun
shines on all the stars and the earth screens none of them.

(3) There is a third theory about the milky way. Some say that it
is a reflection of our sight to the sun, just as they say that the
comet is.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:41:35 pm
But this too is impossible. For if the eye and the mirror and the
whole of the object were severally at rest, then the same part of
the image would appear at the same point in the mirror. But if the
mirror and the object move, keeping the same distance from the eye
which is at rest, but at different rates of speed and so not always
at the same interval from one another, then it is impossible for the
same image always to appear in the same part of the mirror. Now the
constellations included in the circle of the milky way move; and so
does the sun, the object to which our sight is reflected; but we stand
still. And the distance of those two from us is constant and uniform,
but their distance from one another varies. For the Dolphin sometimes
rises at midnight, sometimes in the morning. But in each case the
same parts of the milky way are found near it. But if it were a reflection
and not a genuine affection of these this ought not to be the case.

Again, we can see the milky way reflected at night in water and similar
mirrors. But under these circumstances it is impossible for our sight
to be reflected to the sun.

These considerations show that the milky way is not the path of one
of the planets, nor the light of imperceptible stars, nor a reflection.
And those are the chief theories handed down by others hitherto.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:41:49 pm
Let us recall our fundamental principle and then explain our views.
We have already laid down that the outermost part of what is called
the air is potentially fire and that therefore when the air is dissolved
by motion, there is separated off a kind of matter-and of this matter
we assert that comets consist. We must suppose that what happens is
the same as in the case of the comets when the matter does not form
independently but is formed by one of the fixed stars or the planets.
Then these stars appear to be fringed, because matter of this kind
follows their course. In the same way, a certain kind of matter follows
the sun, and we explain the halo as a reflection from it when the
air is of the right constitution. Now we must assume that what happens
in the case of the stars severally happens in the case of the whole
of the heavens and all the upper motion. For it is natural to suppose
that, if the motion of a single star excites a flame, that of all
the stars should have a similar result, and especially in that region
in which the stars are biggest and most numerous and nearest to one
another. Now the circle of the zodiac dissolves this kind of matter
because of the motion of the sun and the planets, and for this reason
most comets are found outside the tropic circles. Again, no fringe
appears round the sun or moon: for they dissolve such matter too quickly
to admit of its formation. But this circle in which the milky way
appears to our sight is the greatest circle, and its position is such
that it extends far outside the tropic circles. Besides the region
is full of the biggest and brightest constellations and also of what
called 'scattered' stars (you have only to look to see this clearly).
So for these reasons all this matter is continually and ceaselessly
collecting there. A proof of the theory is this: In the circle itself
the light is stronger in that half where the milky way is divided,
and in it the constellations are more numerous and closer to one another
than in the other half; which shows that the cause of the light is
the motion of the constellations and nothing else. For if it is found
in the circle in which there are most constellations and at that point
in the circle at which they are densest and contain the biggest and
the most stars, it is natural to suppose that they are the true cause
of the affection in question. The circle and the constellations in
it may be seen in the diagram. The so-called 'scattered' stars it
is not possible to set down in the same way on the sphere because
none of them have an evident permanent position; but if you look up
to the sky the point is clear. For in this circle alone are the intervals
full of these stars: in the other circles there are obvious gaps.
Hence if we accept the cause assigned for the appearance of comets
as plausible we must assume that the same kind of thing holds good
of the milky way. For the fringe which in the former case is an affection
of a single star here forms in the same way in relation to a whole
circle. So if we are to define the milky way we may call it 'a fringe
attaching to the greatest circle, and due to the matter secreted'.
This, as we said before, explains why there are few comets and why
they appear rarely; it is because at each revolution of the heavens
this matter has always been and is always being separated off and
gathered into this region.

We have now explained the phenomena that occur in that part of the
terrestrial world which is continuous with the motions of the heavens,
namely, shooting-stars and the burning flame, comets and the milky
way, these being the chief affections that appear in that region.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:42:03 pm
Part 9

Let us go on to treat of the region which follows next in order after
this and which immediately surrounds the earth. It is the region common
to water and air, and the processes attending the formation of water
above take place in it. We must consider the principles and causes
of all these phenomena too as before. The efficient and chief and
first cause is the circle in which the sun moves. For the sun as it
approaches or recedes, obviously causes dissipation and condensation
and so gives rise to generation and destruction. Now the earth remains
but the moisture surrounding it is made to evaporate by the sun's
rays and the other heat from above, and rises. But when the heat which
was raising it leaves it, in part dispersing to the higher region,
in part quenched through rising so far into the upper air, then the
vapour cools because its heat is gone and because the place is cold,
and condenses again and turns from air into water. And after the water
has formed it falls down again to the earth.

The exhalation of water is vapour: air condensing into water is cloud.
Mist is what is left over when a cloud condenses into water, and is
therefore rather a sign of fine weather than of rain; for mist might
be called a barren cloud. So we get a circular process that follows
the course of the sun. For according as the sun moves to this side
or that, the moisture in this process rises or falls. We must think
of it as a river flowing up and down in a circle and made up partly
of air, partly of water. When the sun is near, the stream of vapour
flows upwards; when it recedes, the stream of water flows down: and
the order of sequence, at all events, in this process always remains
the same. So if 'Oceanus' had some secret meaning in early writers,
perhaps they may have meant this river that flows in a circle about
the earth.

So the moisture is always raised by the heat and descends to the earth
again when it gets cold. These processes and, in some cases, their
varieties are distinguished by special names. When the water falls
in small drops it is called a drizzle; when the drops are larger it
is rain.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:42:17 pm
Part 10

Some of the vapour that is formed by day does not rise high because
the ratio of the fire that is raising it to the water that is being
raised is small. When this cools and descends at night it is called
dew and hoar-frost. When the vapour is frozen before it has condensed
to water again it is hoar-frost; and this appears in winter and is
commoner in cold places. It is dew when the vapour has condensed into
water and the heat is not so great as to dry up the moisture that
has been raised nor the cold sufficient (owing to the warmth of the
climate or season) for the vapour itself to freeze. For dew is more
commonly found when the season or the place is warm, whereas the opposite,
as has been said, is the case with hoar-frost. For obviously vapour
is warmer than water, having still the fire that raised it: consequently
more cold is needed to freeze it.

Both dew and hoar-frost are found when the sky is clear and there
is no wind. For the vapour could not be raised unless the sky were
clear, and if a wind were blowing it could not condense.

The fact that hoar-frost is not found on mountains contributes to
prove that these phenomena occur because the vapour does not rise
high. One reason for this is that it rises from hollow and watery
places, so that the heat that is raising it, bearing as it were too
heavy a burden cannot lift it to a great height but soon lets it fall
again. A second reason is that the motion of the air is more pronounced
at a height, and this dissolves a gathering of this kind.

Everywhere, except in Pontus, dew is found with south winds and not
with north winds. There the opposite is the case and it is found with
north winds and not with south. The reason is the same as that which
explains why dew is found in warm weather and not in cold. For the
south wind brings warm, and the north, wintry weather. For the north
wind is cold and so quenches the heat of the evaporation. But in Pontus
the south wind does not bring warmth enough to cause evaporation,
whereas the coldness of the north wind concentrates the heat by a
sort of recoil, so that there is more evaporation and not less. This
is a thing which we can often observe in other places too. Wells,
for instance, give off more vapour in a north than in a south wind.
Only the north winds quench the heat before any considerable quantity
of vapour has gathered, while in a south wind the evaporation is allowed
to accumulate.

Water, once formed, does not freeze on the surface of the earth, in
the way that it does in the region of the clouds.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:42:34 pm
Part 11

From the latter there fall three bodies condensed by cold, namely
rain, snow, hail. Two of these correspond to the phenomena on the
lower level and are due to the same causes, differing from them only
in degree and quantity.

Snow and hoar-frost are one and the same thing, and so are rain and
dew: only there is a great deal of the former and little of the latter.
For rain is due to the cooling of a great amount of vapour, for the
region from which and the time during which the vapour is collected
are considerable. But of dew there is little: for the vapour collects
for it in a single day and from a small area, as its quick formation
and scanty quantity show.

The relation of hoar-frost and snow is the same: when cloud freezes
there is snow, when vapour freezes there is hoar-frost. Hence snow
is a sign of a cold season or country. For a great deal of heat is
still present and unless the cold were overpowering it the cloud would
not freeze. For there still survives in it a great deal of the heat
which caused the moisture to rise as vapour from the earth.

Hail on the other hand is found in the upper region, but the corresponding
phenomenon in the vaporous region near the earth is lacking. For,
as we said, to snow in the upper region corresponds hoar-frost in
the lower, and to rain in the upper region, dew in the lower. But
there is nothing here to correspond to hail in the upper region. Why
this is so will be clear when we have explained the nature of hail.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:42:53 pm
Part 12

But we must go on to collect the facts bearing on the origin of it,
both those which raise no difficulties and those which seem paradoxical.

Hail is ice, and water freezes in winter; yet hailstorms occur chiefly
in spring and autumn and less often in the late summer, but rarely
in winter and then only when the cold is less intense. And in general
hailstorms occur in warmer, and snow in colder places. Again, there
is a difficulty about water freezing in the upper region. It cannot
have frozen before becoming water: and water cannot remain suspended
in the air for any space of time. Nor can we say that the case is
like that of particles of moisture which are carried up owing to their
small size and rest on the iar (the water swimming on the air just
as small particles of earth and gold often swim on water). In that
case large drops are formed by the union of many small, and so fall
down. This cannot take place in the case of hail, since solid bodies
cannot coalesce like liquid ones. Clearly then drops of that size
were suspended in the air or else they could not have been so large
when frozen.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:43:10 pm
Some think that the cause and origin of hail is this. The cloud is
thrust up into the upper atmosphere, which is colder because the reflection
of the sun's rays from the earth ceases there, and upon its arrival
there the water freezes. They think that this explains why hailstorms
are commoner in summer and in warm countries; the heat is greater
and it thrusts the clouds further up from the earth. But the fact
is that hail does not occur at all at a great height: yet it ought
to do so, on their theory, just as we see that snow falls most on
high mountains. Again clouds have often been observed moving with
a great noise close to the earth, terrifying those who heard and saw
them as portents of some catastrophe. Sometimes, too, when such clouds
have been seen, without any noise, there follows a violent hailstorm,
and the stones are of incredible size, and angular in shape. This
shows that they have not been falling for long and that they were
frozen near to the earth, and not as that theory would have it. Moreover,
where the hailstones are large, the cause of their freezing must be
present in the highest degree: for hail is ice as every one can see.
Now those hailstones are large which are angular in shape. And this
shows that they froze close to the earth, for those that fall far
are worn away by the length of their fall and become round and smaller
in size.

It clearly follows that the congelation does not take place because
the cloud is thrust up into the cold upper region.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:43:25 pm
Now we see that warm and cold react upon one another by recoil. Hence
in warm weather the lower parts of the earth are cold and in a frost
they are warm. The same thing, we must suppose, happens in the air,
so that in the warmer seasons the cold is concentrated by the surrounding
heat and causes the cloud to go over into water suddenly. (For this
reason rain-drops are much larger on warm days than in winter, and
showers more violent. A shower is said to be more violent in proportion
as the water comes down in a body, and this happens when the condensation
takes place quickly,-though this is just the opposite of what Anaxagoras
says. He says that this happens when the cloud has risen into the
cold air; whereas we say that it happens when the cloud has descended
into the warm air, and that the more the further the cloud has descended).
But when the cold has been concentrated within still more by the outer
heat, it freezes the water it has formed and there is hail. We get
hail when the process of freezing is quicker than the descent of the
water. For if the water falls in a certain time and the cold is sufficient
to freeze it in less, there is no difficulty about its having frozen
in the air, provided that the freezing takes place in a shorter time
than its fall. The nearer to the earth, and the more suddenly, this
process takes place, the more violent is the rain that results and
the larger the raindrops and the hailstones because of the shortness
of their fall. For the same reason large raindrops do not fall thickly.
Hail is rarer in summer than in spring and autumn, though commoner
than in winter, because the air is drier in summer, whereas in spring
it is still moist, and in autumn it is beginning to grow moist. It
is for the same reason that hailstorms sometimes occur in the late
summer as we have said.

The fact that the water has previously been warmed contributes to
its freezing quickly: for so it cools sooner. Hence many people, when
they want to cool hot water quickly, begin by putting it in the sun.
So the inhabitants of Pontus when they encamp on the ice to fish (they
cut a hole in the ice and then fish) pour warm water round their reeds
that it may freeze the quicker, for they use the ice like lead to
fix the reeds. Now it is in hot countries and seasons that the water
which forms soon grows warm.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:43:38 pm
It is for the same reason that rain falls in summer and not in winter
in Arabia and Ethiopia too, and that in torrents and repeatedly on
the same day. For the concentration or recoil due to the extreme heat
of the country cools the clouds quickly.

So much for an account of the nature and causes of rain, dew, snow,
hoar-frost, and hail.

Part 13

Let us explain the nature of winds, and all windy vapours, also of
rivers and of the sea. But here, too, we must first discuss the difficulties
involved: for, as in other matters, so in this no theory has been
handed down to us that the most ordinary man could not have thought
of.

Some say that what is called air, when it is in motion and flows,
is wind, and that this same air when it condenses again becomes cloud
and water, implying that the nature of wind and water is the same.
So they define wind as a motion of the air. Hence some, wishing to
say a clever thing, assert that all the winds are one wind, because
the air that moves is in fact all of it one and the same; they maintain
that the winds appear to differ owing to the region from which the
air may happen to flow on each occasion, but really do not differ
at all. This is just like thinking that all rivers are one and the
same river, and the ordinary unscientific view is better than a scientific
theory like this. If all rivers flow from one source, and the same
is true in the case of the winds, there might be some truth in this
theory; but if it is no more true in the one case than in the other,
this ingenious idea is plainly false. What requires investigation
is this: the nature of wind and how it originates, its efficient cause
and whence they derive their source; whether one ought to think of
the wind as issuing from a sort of vessel and flowing until the vessel
is empty, as if let out of a wineskin, or, as painters represent the
winds, as drawing their source from themselves.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:43:50 pm
We find analogous views about the origin of rivers. It is thought
that the water is raised by the sun and descends in rain and gathers
below the earth and so flows from a great reservoir, all the rivers
from one, or each from a different one. No water at all is generated,
but the volume of the rivers consists of the water that is gathered
into such reservoirs in winter. Hence rivers are always fuller in
winter than in summer, and some are perennial, others not. Rivers
are perennial where the reservoir is large and so enough water has
collected in it to last out and not be used up before the winter rain
returns. Where the reservoirs are smaller there is less water in the
rivers, and they are dried up and their vessel empty before the fresh
rain comes on.

But if any one will picture to himself a reservoir adequate to the
water that is continuously flowing day by day, and consider the amount
of the water, it is obvious that a receptacle that is to contain all
the water that flows in the year would be larger than the earth, or,
at any rate, not much smaller.

Though it is evident that many reservoirs of this kind do exist in
many parts of the earth, yet it is unreasonable for any one to refuse
to admit that air becomes water in the earth for the same reason as
it does above it. If the cold causes the vaporous air to condense
into water above the earth we must suppose the cold in the earth to
produce this same effect, and recognize that there not only exists
in it and flows out of it actually formed water, but that water is
continually forming in it too.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:44:09 pm
Again, even in the case of the water that is not being formed from
day to day but exists as such, we must not suppose as some do that
rivers have their source in definite subterranean lakes. On the contrary,
just as above the earth small drops form and these join others, till
finally the water descends in a body as rain, so too we must suppose
that in the earth the water at first trickles together little by little,
and that the sources of the rivers drip, as it were, out of the earth
and then unite. This is proved by facts. When men construct an aqueduct
they collect the water in pipes and trenches, as if the earth in the
higher ground were sweating the water out. Hence, too, the head-waters
of rivers are found to flow from mountains, and from the greatest
mountains there flow the most numerous and greatest rivers. Again,
most springs are in the neighbourhood of mountains and of high ground,
whereas if we except rivers, water rarely appears in the plains. For
mountains and high ground, suspended over the country like a saturated
sponge, make the water ooze out and trickle together in minute quantities
but in many places. They receive a great deal of water falling as
rain (for it makes no difference whether a spongy receptacle is concave
and turned up or convex and turned down: in either case it will contain
the same volume of matter) and, they also cool the vapour that rises
and condense it back into water.

Hence, as we said, we find that the greatest rivers flow from the
greatest mountains. This can be seen by looking at itineraries: what
is recorded in them consists either of things which the writer has
seen himself or of such as he has compiled after inquiry from those
who have seen them.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:44:28 pm
In Asia we find that the most numerous and greatest rivers flow from
the mountain called Parnassus, admittedly the greatest of all mountains
towards the south-east. When you have crossed it you see the outer
ocean, the further limit of which is unknown to the dwellers in our
world. Besides other rivers there flow from it the Bactrus, the Choaspes,
the Araxes: from the last a branch separates off and flows into lake
Maeotis as the Tanais. From it, too, flows the Indus, the volume of
whose stream is greatest of all rivers. From the Caucasus flows the
Phasis, and very many other great rivers besides. Now the Caucasus
is the greatest of the mountains that lie to the northeast, both as
regards its extent and its height. A proof of its height is the fact
that it can be seen from the so-called 'deeps' and from the entrance
to the lake. Again, the sun shines on its peaks for a third part of
the night before sunrise and again after sunset. Its extent is proved
by the fact that thought contains many inhabitable regions which are
occupied by many nations and in which there are said to be great lakes,
yet they say that all these regions are visible up to the last peak.
From Pyrene (this is a mountain towards the west in Celtice) there
flow the Istrus and the Tartessus. The latter flows outside the pillars,
while the Istrus flows through all Europe into the Euxine. Most of
the remaining rivers flow northwards from the Hercynian mountains,
which are the greatest in height and extent about that region. In
the extreme north, beyond furthest Scythia, are the mountains called
Rhipae. The stories about their size are altogether too fabulous:
however, they say that the most and (after the Istrus) the greatest
rivers flow from them. So, too, in Libya there flow from the Aethiopian
mountains the Aegon and the Nyses; and from the so-called Silver Mountain
the two greatest of named rivers, the river called Chremetes that
flows into the outer ocean, and the main source of the Nile. Of the
rivers in the Greek world, the Achelous flows from Pindus, the Inachus
from the same mountain; the Strymon, the Nestus, and the Hebrus all
three from Scombrus; many rivers, too, flow from Rhodope.

All other rivers would be found to flow in the same way, but we have
mentioned these as examples. Even where rivers flow from marshes,
the marshes in almost every case are found to lie below mountains
or gradually rising ground.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:44:44 pm
It is clear then that we must not suppose rivers to originate from
definite reservoirs: for the whole earth, we might almost say, would
not be sufficient (any more than the region of the clouds would be)
if we were to suppose that they were fed by actually existing water
only and it were not the case that as some water passed out of existence
some more came into existence, but rivers always drew their stream
from an existing store. Secondly, the fact that rivers rise at the
foot of mountains proves that a place transmits the water it contains
by gradual percolation of many drops, little by little, and that this
is how the sources of rivers originate. However, there is nothing
impossible about the existence of such places containing a quantity
of water like lakes: only they cannot be big enough to produce the
supposed effect. To think that they are is just as absurd as if one
were to suppose that rivers drew all their water from the sources
we see (for most rivers do flow from springs). So it is no more reasonable
to suppose those lakes to contain the whole volume of water than these
springs.

That there exist such chasms and cavities in the earth we are taught
by the rivers that are swallowed up. They are found in many parts
of the earth: in the Peloponnesus, for instance, there are many such
rivers in Arcadia. The reason is that Arcadia is mountainous and there
are no channels from its valleys to the sea. So these places get full
of water, and this, having no outlet, under the pressure of the water
that is added above, finds a way out for itself underground. In Greece
this kind of thing happens on quite a small scale, but the lake at
the foot of the Caucasus, which the inhabitants of these parts call
a sea, is considerable. Many great rivers fall into it and it has
no visible outlet but issues below the earth off the land of the Coraxi
about the so-called 'deeps of Pontus'. This is a place of unfathomable
depth in the sea: at any rate no one has yet been able to find bottom
there by sounding. At this spot, about three hundred stadia from land,
there comes up sweet water over a large area, not all of it together
but in three places. And in Liguria a river equal in size to the Rhodanus
is swallowed up and appears again elsewhere: the Rhodanus being a
navigable river.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:45:02 pm
Part 14

The same parts of the earth are not always moist or dry, but they
change according as rivers come into existence and dry up. And so
the relation of land to sea changes too and a place does not always
remain land or sea throughout all time, but where there was dry land
there comes to be sea, and where there is now sea, there one day comes
to be dry land. But we must suppose these changes to follow some order
and cycle. The principle and cause of these changes is that the interior
of the earth grows and decays, like the bodies of plants and animals.
Only in the case of these latter the process does not go on by parts,
but each of them necessarily grows or decays as a whole, whereas it
does go on by parts in the case of the earth. Here the causes are
cold and heat, which increase and diminish on account of the sun and
its course. It is owing to them that the parts of the earth come to
have a different character, that some parts remain moist for a certain
time, and then dry up and grow old, while other parts in their turn
are filled with life and moisture. Now when places become drier the
springs necessarily give out, and when this happens the rivers first
decrease in size and then finally become dry; and when rivers change
and disappear in one part and come into existence correspondingly
in another, the sea must needs be affected.

If the sea was once pushed out by rivers and encroached upon the land
anywhere, it necessarily leaves that place dry when it recedes; again,
if the dry land has encroached on the sea at all by a process of silting
set up by the rivers when at their full, the time must come when this
place will be flooded again.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:45:20 pm
But the whole vital process of the earth takes place so gradually
and in periods of time which are so immense compared with the length
of our life, that these changes are not observed, and before their
course can be recorded from beginning to end whole nations perish
and are destroyed. Of such destructions the most utter and sudden
are due to wars; but pestilence or famine cause them too. Famines,
again, are either sudden and severe or else gradual. In the latter
case the disappearance of a nation is not noticed because some leave
the country while others remain; and this goes on until the land is
unable to maintain any inhabitants at all. So a long period of time
is likely to elapse from the first departure to the last, and no one
remembers and the lapse of time destroys all record even before the
last inhabitants have disappeared. In the same way a nation must be
supposed to lose account of the time when it first settled in a land
that was changing from a marshy and watery state and becoming dry.
Here, too, the change is gradual and lasts a long time and men do
not remember who came first, or when, or what the land was like when
they came. This has been the case with Egypt. Here it is obvious that
the land is continually getting drier and that the whole country is
a deposit of the river Nile. But because the neighbouring peoples
settled in the land gradually as the marshes dried, the lapse of time
has hidden the beginning of the process. However, all the mouths of
the Nile, with the single exception of that at Canopus, are obviously
artificial and not natural. And Egypt was nothing more than what is
called Thebes, as Homer, too, shows, modern though he is in relation
to such changes. For Thebes is the place that he mentions; which implies
that Memphis did not yet exist, or at any rate was not as important
as it is now. That this should be so is natural, since the lower land
came to be inhabited later than that which lay higher. For the parts
that lie nearer to the place where the river is depositing the silt
are necessarily marshy for a longer time since the water always lies
most in the newly formed land. But in time this land changes its character,
and in its turn enjoys a period of prosperity. For these places dry
up and come to be in good condition while the places that were formerly
well-tempered some day grow excessively dry and deteriorate. This
happened to the land of Argos and Mycenae in Greece. In the time of
the Trojan wars the Argive land was marshy and could only support
a small population, whereas the land of Mycenae was in good condition
(and for this reason Mycenae was the superior). But now the opposite
is the case, for the reason we have mentioned: the land of Mycenae
has become completely dry and barren, while the Argive land that was
formerly barren owing to the water has now become fruitful. Now the
same process that has taken place in this small district must be supposed
to be going on over whole countries and on a large scale.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:45:32 pm
Men whose outlook is narrow suppose the cause of such events to be
change in the universe, in the sense of a coming to be of the world
as a whole. Hence they say that the sea being dried up and is growing
less, because this is observed to have happened in more places now
than formerly. But this is only partially true. It is true that many
places are now dry, that formerly were covered with water. But the
opposite is true too: for if they look they will find that there are
many places where the sea has invaded the land. But we must not suppose
that the cause of this is that the world is in process of becoming.
For it is absurd to make the universe to be in process because of
small and trifling changes, when the bulk and size of the earth are
surely as nothing in comparison with the whole world. Rather we must
take the cause of all these changes to be that, just as winter occurs
in the seasons of the year, so in determined periods there comes a
great winter of a great year and with it excess of rain. But this
excess does not always occur in the same place. The deluge in the
time of Deucalion, for instance, took place chiefly in the Greek world
and in it especially about ancient Hellas, the country about Dodona
and the Achelous, a river which has often changed its course. Here
the Selli dwelt and those who were formerly called Graeci and now
Hellenes. When, therefore, such an excess of rain occurs we must suppose
that it suffices for a long time. We have seen that some say that
the size of the subterranean cavities is what makes some rivers perennial
and others not, whereas we maintain that the size of the mountains
is the cause, and their density and coldness; for great, dense, and
cold mountains catch and keep and create most water: whereas if the
mountains that overhang the sources of rivers are small or porous
and stony and clayey, these rivers run dry earlier. We must recognize
the same kind of thing in this case too. Where such abundance of rain
falls in the great winter it tends to make the moisture of those places
almost everlasting. But as time goes on places of the latter type
dry up more, while those of the former, moist type, do so less: until
at last the beginning of the same cycle returns.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:45:45 pm
Since there is necessarily some change in the whole world, but not
in the way of coming into existence or perishing (for the universe
is permanent), it must be, as we say, that the same places are not
for ever moist through the presence of sea and rivers, nor for ever
dry. And the facts prove this. The whole land of the Egyptians, whom
we take to be the most ancient of men, has evidently gradually come
into existence and been produced by the river. This is clear from
an observation of the country, and the facts about the Red Sea suffice
to prove it too. One of their kings tried to make a canal to it (for
it would have been of no little advantage to them for the whole region
to have become navigable; Sesostris is said to have been the first
of the ancient kings to try), but he found that the sea was higher
than the land. So he first, and Darius afterwards, stopped making
the canal, lest the sea should mix with the river water and spoil
it. So it is clear that all this part was once unbroken sea. For the
same reason Libya-the country of Ammon-is, strangely enough, lower
and hollower than the land to the seaward of it. For it is clear that
a barrier of silt was formed and after it lakes and dry land, but
in course of time the water that was left behind in the lakes dried
up and is now all gone. Again the silting up of the lake Maeotis by
the rivers has advanced so much that the limit to the size of the
ships which can now sail into it to trade is much lower than it was
sixty years ago. Hence it is easy to infer that it, too, like most
lakes, was originally produced by the rivers and that it must end
by drying up entirely.

Again, this process of silting up causes a continuous current through
the Bosporus; and in this case we can directly observe the nature
of the process. Whenever the current from the Asiatic shore threw
up a sandbank, there first formed a small lake behind it. Later it
dried up and a second sandbank formed in front of the first and a
second lake. This process went on uniformly and without interruption.
Now when this has been repeated often enough, in the course of time
the strait must become like a river, and in the end the river itself
must dry up.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:46:09 pm
So it is clear, since there will be no end to time and the world is
eternal, that neither the Tanais nor the Nile has always been flowing,
but that the region whence they flow was once dry: for their effect
may be fulfilled, but time cannot. And this will be equally true of
all other rivers. But if rivers come into existence and perish and
the same parts of the earth were not always moist, the sea must needs
change correspondingly. And if the sea is always advancing in one
place and receding in another it is clear that the same parts of the
whole earth are not always either sea or land, but that all this changes
in course of time.

So we have explained that the same parts of the earth are not always
land or sea and why that is so: and also why some rivers are perennial
and others not.

----------------------------------------------------------------------

BOOK II

Part 1

Let us explain the nature of the sea and the reason why such a large
mass of water is salt and the way in which it originally came to be.

The old writers who invented theogonies say that the sea has springs,
for they want earth and sea to have foundations and roots of their
own. Presumably they thought that this view was grander and more impressive
as implying that our earth was an important part of the universe.
For they believed that the whole world had been built up round our
earth and for its sake, and that the earth was the most important
and primary part of it. Others, wiser in human knowledge, give an
account of its origin. At first, they say, the earth was surrounded
by moisture. Then the sun began to dry it up, part of it evaporated
and is the cause of winds and the turnings back of the sun and the
moon, while the remainder forms the sea. So the sea is being dried
up and is growing less, and will end by being some day entirely dried
up. Others say that the sea is a kind of sweat exuded by the earth
when the sun heats it, and that this explains its saltness: for all
sweat is salt. Others say that the saltness is due to the earth. Just
as water strained through ashes becomes salt, so the sea owes its
saltness to the admixture of earth with similar properties.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:46:21 pm
We must now consider the facts which prove that the sea cannot possibly
have springs. The waters we find on the earth either flow or are stationary.
All flowing water has springs. (By a spring, as we have explained
above, we must not understand a source from which waters are ladled
as it were from a vessel, but a first point at which the water which
is continually forming and percolating gathers.) Stationary water
is either that which has collected and has been left standing, marshy
pools, for instance, and lakes, which differ merely in size, or else
it comes from springs. In this case it is always artificial, I mean
as in the case of wells, otherwise the spring would have to be above
the outlet. Hence the water from fountains and rivers flows of itself,
whereas wells need to be worked artificially. All the waters that
exist belong to one or other of these classes.

On the basis of this division we can sec that the sea cannot have
springs. For it falls under neither of the two classes; it does not
flow and it is not artificial; whereas all water from springs must
belong to one or other of them. Natural standing water from springs
is never found on such a large scale.

Again, there are several seas that have no communication with one
another at all. The Red Sea, for instance, communicates but slightly
with the ocean outside the straits, and the Hyrcanian and Caspian
seas are distinct from this ocean and people dwell all round them.
Hence, if these seas had had any springs anywhere they must have been
discovered.

It is true that in straits, where the land on either side contracts
an open sea into a small space, the sea appears to flow. But this
is because it is swinging to and fro. In the open sea this motion
is not observed, but where the land narrows and contracts the sea
the motion that was imperceptible in the open necessarily strikes
the attention.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:46:39 pm
The whole of the Mediterranean does actually flow. The direction of
this flow is determined by the depth of the basins and by the number
of rivers. Maeotis flows into Pontus and Pontus into the Aegean. After
that the flow of the remaining seas is not so easy to observe. The
current of Maeotis and Pontus is due to the number of rivers (more
rivers flow into the Euxine and Maeotis than into the whole Mediterranean
with its much larger basin), and to their own shallowness. For we
find the sea getting deeper and deeper. Pontus is deeper than Maeotis,
the Aegean than Pontus, the Sicilian sea than the Aegean; the Sardinian
and Tyrrhenic being the deepest of all. (Outside the pillars of Heracles
the sea is shallow owing to the mud, but calm, for it lies in a hollow.)
We see, then, that just as single rivers flow from mountains, so it
is with the earth as a whole: the greatest volume of water flows from
the higher regions in the north. Their alluvium makes the northern
seas shallow, while the outer seas are deeper. Some further evidence
of the height of the northern regions of the earth is afforded by
the view of many of the ancient meteorologists. They believed that
the sun did not pass below the earth, but round its northern part,
and that it was the height of this which obscured the sun and caused
night.

So much to prove that there cannot be sources of the sea and to explain
its observed flow.

Part 2

We must now discuss the origin of the sea, if it has an origin, and
the cause of its salt and bitter taste.

What made earlier writers consider the sea to be the original and
main body of water is this. It seems reasonable to suppose that to
be the case on the analogy of the other elements. Each of them has
a main bulk which by reason of its mass is the origin of that element,
and any parts which change and mix with the other elements come from
it. Thus the main body of fire is in the upper region; that of air
occupies the place next inside the region of fire; while the mass
of the earth is that round which the rest of the elements are seen
to lie. So we must clearly look for something analogous in the case
of water. But here we can find no such single mass, as in the case
of the other elements, except the sea. River water is not a unity,
nor is it stable, but is seen to be in a continuous process of becoming
from day to day. It was this difficulty which made people regard the
sea as the origin and source of moisture and of all water. And so
we find it maintained that rivers not only flow into the sea but originate
from it, the salt water becoming sweet by filtration.

But this view involves another difficulty. If this body of water is
the origin and source of all water, why is it salt and not sweet?
The reason for this, besides answering this question, will ensure
our having a right first conception of the nature of the sea.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:46:52 pm
The earth is surrounded by water, just as that is by the sphere of
air, and that again by the sphere called that of fire (which is the
outermost both on the common view and on ours). Now the sun, moving
as it does, sets up processes of change and becoming and decay, and
by its agency the finest and sweetest water is every day carried up
and is dissolved into vapour and rises to the upper region, where
it is condensed again by the cold and so returns to the earth. This,
as we have said before, is the regular course of nature.

Hence all my predecessors who supposed that the sun was nourished
by moisture are absurdly mistaken. Some go on to say that the solstices
are due to this, the reason being that the same places cannot always
supply the sun with nourishment and that without it he must perish.
For the fire we are familiar with lives as long as it is fed, and
the only food for fire is moisture. As if the moisture that is raised
could reach the sun! or this ascent were really like that performed
by flame as it comes into being, and to which they supposed the case
of the sun to be analogous! Really there is no similarity. A flame
is a process of becoming, involving a constant interchange of moist
and dry. It cannot be said to be nourished since it scarcely persists
as one and the same for a moment. This cannot be true of the sun;
for if it were nourished like that, as they say it is, we should obviously
not only have a new sun every day, as Heraclitus says, but a new sun
every moment. Again, when the sun causes the moisture to rise, this
is like fire heating water. So, as the fire is not fed by the water
above it, it is absurd to suppose that the sun feeds on that moisture,
even if its heat made all the water in the world evaporate. Again,
it is absurd, considering the number and size of the stars, that these
thinkers should consider the sun only and overlook the question how
the rest of the heavenly bodies subsist. Again, they are met by the
same difficulty as those who say that at first the earth itself was
moist and the world round the earth was warmed by the sun, and so
air was generated and the whole firmament grew, and the air caused
winds and solstices. The objection is that we always plainly see the
water that has been carried up coming down again. Even if the same
amount does not come back in a year or in a given country, yet in
a certain period all that has been carried up is returned. This implies
that the celestial bodies do not feed on it, and that we cannot distinguish
between some air which preserves its character once it is generated
and some other which is generated but becomes water again and so perishes;
on the contrary, all the moisture alike is dissolved and all of it
condensed back into water.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:47:06 pm
The drinkable, sweet water, then, is light and is all of it drawn
up: the salt water is heavy and remains behind, but not in its natural
place. For this is a question which has been sufficiently discussed
(I mean about the natural place that water, like the other elements,
must in reason have), and the answer is this. The place which we see
the sea filling is not its natural place but that of water. It seems
to belong to the sea because the weight of the salt water makes it
remain there, while the sweet, drinkable water which is light is carried
up. The same thing happens in animal bodies. Here, too, the food when
it enters the body is sweet, yet the residuum and dregs of liquid
food are found to be bitter and salt. This is because the sweet and
drinkable part of it has been drawn away by the natural animal heat
and has passed into the flesh and the other parts of the body according
to their several natures. Now just as here it would be wrong for any
one to refuse to call the belly the place of liquid food because that
disappears from it soon, and to call it the place of the residuum
because this is seen to remain, so in the case of our present subject.
This place, we say, is the place of water. Hence all rivers and all
the water that is generated flow into it: for water flows into the
deepest place, and the deepest part of the earth is filled by the
sea. Only all the light and sweet part of it is quickly carried off
by the sun, while herest remains for the reason we have explained.
It is quite natural that some people should have been puzzled by the
old question why such a mass of water leaves no trace anywhere (for
the sea does not increase though innumerable and vast rivers are flowing
into it every day.) But if one considers the matter the solution is
easy. The same amount of water does not take as long to dry up when
it is spread out as when it is gathered in a body, and indeed the
difference is so great that in the one case it might persist the whole
day long while in the other it might all disappear in a moment-as
for instance if one were to spread out a cup of water over a large
table. This is the case with the rivers: all the time they are flowing
their water forms a compact mass, but when it arrives at a vast wide
place it quickly and imperceptibly evaporates.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:47:20 pm
But the theory of the Phaedo about rivers and the sea is impossible.
There it is said that the earth is pierced by intercommunicating channels
and that the original head and source of all waters is what is called
Tartarus-a mass of water about the centre, from which all waters,
flowing and standing, are derived. This primary and original water
is always surging to and fro, and so it causes the rivers to flow
on this side of the earth's centre and on that; for it has no fixed
seat but is always oscillating about the centre. Its motion up and
down is what fills rivers. Many of these form lakes in various places
(our sea is an instance of one of these), but all of them come round
again in a circle to the original source of their flow, many at the
same point, but some at a point opposite to that from which they issued;
for instance, if they started from the other side of the earth's centre,
they might return from this side of it. They descend only as far as
the centre, for after that all motion is upwards. Water gets its tastes
and colours from the kind of earth the rivers happened to flow through.

But on this theory rivers do not always flow in the same sense. For
since they flow to the centre from which they issue forth they will
not be flowing down any more than up, but in whatever direction the
surging of Tartarus inclines to. But at this rate we shall get the
proverbial rivers flowing upwards, which is impossible. Again, where
is the water that is generated and what goes up again as vapour to
come from? For this must all of it simply be ignored, since the quantity
of water is always the same and all the water that flows out from
the original source flows back to it again. This itself is not true,
since all rivers are seen to end in the sea except where one flows
into another. Not one of them ends in the earth, but even when one
is swallowed up it comes to the surface again. And those rivers are
large which flow for a long distance through a lowying country, for
by their situation and length they cut off the course of many others
and swallow them up. This is why the Istrus and the Nile are the greatest
of the rivers which flow into our sea. Indeed, so many rivers fall
into them that there is disagreement as to the sources of them both.
All of which is plainly impossible on the theory, and the more so
as it derives the sea from Tartarus.

Enough has been said to prove that this is the natural place of water
and not of the sea, and to explain why sweet water is only found in
rivers, while salt water is stationary, and to show that the sea is
the end rather than the source of water, analogous to the residual
matter of all food, and especially liquid food, in animal bodies.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:47:36 pm
Part 3

We must now explain why the sea is salt, and ask whether it eternally
exists as identically the same body, or whether it did not exist at
all once and some day will exist no longer, but will dry up as some
people think.

Every one admits this, that if the whole world originated the sea
did too; for they make them come into being at the same time. It follows
that if the universe is eternal the same must be true of the sea.
Any one who thinks like Democritus that the sea is diminishing and
will disappear in the end reminds us of Aesop's tales. His story was
that Charybdis had twice sucked in the sea: the first time she made
the mountains visible; the second time the islands; and when she sucks
it in for the last time she will dry it up entirely. Such a tale is
appropriate enough to Aesop in a rage with the ferryman, but not to
serious inquirers. Whatever made the sea remain at first, whether
it was its weight, as some even of those who hold these views say
(for it is easy to see the cause here), or some other reason-clearly
the same thing must make it persist for ever. They must either deny
that the water raised by the sun will return at all, or, if it does,
they must admit that the sea persists for ever or as long as this
process goes on, and again, that for the same period of time that
sweet water must have been carried up beforehand. So the sea will
never dry up: for before that can happen the water that has gone up
beforehand will return to it: for if you say that this happens once
you must admit its recurrence. If you stop the sun's course there
is no drying agency. If you let it go on it will draw up the sweet
water as we have said whenever it approaches, and let it descend again
when it recedes. This notion about the sea is derived from the fact
that many places are found to be drier now than they once were. Why
this is so we have explained. The phenomenon is due to temporary excess
of rain and not to any process of becoming in which the universe or
its parts are involved. Some day the opposite will take place and
after that the earth will grow dry once again. We must recognize that
this process always goes on thus in a cycle, for that is more satisfactory
than to suppose a change in the whole world in order to explain these
facts. But we have dwelt longer on this point than it deserves.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:47:51 pm
To return to the saltness of the sea: those who create the sea once
for all, or indeed generate it at all, cannot account for its saltness.
It makes no difference whether the sea is the residue of all the moisture
that is about the earth and has been drawn up by the sun, or whether
all the flavour existing in the whole mass of sweet water is due to
the admixture of a certain kind of earth. Since the total volume of
the sea is the same once the water that evaporated has returned, it
follows that it must either have been salt at first too, or, if not
at first, then not now either. If it was salt from the very beginning,
then we want to know why that was so; and why, if salt water was drawn
up then, that is not the case now.

Again, if it is maintained that an admixture of earth makes the sea
salt (for they say that earth has many flavours and is washed down
by the rivers and so makes the sea salt by its admixture), it is strange
that rivers should not be salt too. How can the admixture of this
earth have such a striking effect in a great quantity of water and
not in each river singly? For the sea, differing in nothing from rivers
but in being salt, is evidently simply the totality of river water,
and the rivers are the vehicle in which that earth is carried to their
common destination.

It is equally absurd to suppose that anything has been explained by
calling the sea 'the sweat of the earth', like Empedicles. Metaphors
are poetical and so that expression of his may satisfy the requirements
of a poem, but as a scientific theory it is unsatisfactory. Even in
the case of the body it is a question how the sweet liquid drunk becomes
salt sweat whether it is merely by the departure of some element in
it which is sweetest, or by the admixture of something, as when water
is strained through ashes. Actually the saltness seems to be due to
the same cause as in the case of the residual liquid that gathers
in the bladder. That, too, becomes bitter and salt though the liquid
we drink and that contained in our food is sweet. If then the bitterness
is due in these cases (as with the water strained through lye) to
the presence of a certain sort of stuff that is carried along by the
urine (as indeed we actually find a salt deposit settling in chamber-pots)
and is secreted from the flesh in sweat (as if the departing moisture
were washing the stuff out of the body), then no doubt the admixture
of something earthy with the water is what makes the sea salt.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:48:05 pm
Now in the body stuff of this kind, viz. the sediment of food, is
due to failure to digest: but how there came to be any such thing
in the earth requires explanation. Besides, how can the drying and
warming of the earth cause the secretion such a great quantity of
water; especially as that must be a mere fragment of what is left
in the earth? Again, waiving the question of quantity, why does not
the earth sweat now when it happens to be in process of drying? If
it did so then, it ought to do so now. But it does not: on the contrary,
when it is dry it graws moist, but when it is moist it does not secrete
anything at all. How then was it possible for the earth at the beginning
when it was moist to sweat as it grew dry? Indeed, the theory that
maintains that most of the moisture departed and was drawn up by the
sun and that what was left over is the sea is more reasonable; but
for the earth to sweat when it is moist is impossible.

Since all the attempts to account for the saltness of the sea seem
unsuccessful let us explain it by the help of the principle we have
used already.

Since we recognize two kinds of evaporation, one moist, the other
dry, it is clear that the latter must be recognized as the source
of phenomena like those we are concerned with.

But there is a question which we must discuss first. Does the sea
always remain numerically one and consisting of the same parts, or
is it, too, one in form and volume while its parts are in continual
change, like air and sweet water and fire? All of these are in a constant
state of change, but the form and the quantity of each of them are
fixed, just as they are in the case of a flowing river or a burning
flame. The answer is clear, and there is no doubt that the same account
holds good of all these things alike. They differ in that some of
them change more rapidly or more slowly than others; and they all
are involved in a process of perishing and becoming which yet affects
them all in a regular course.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:48:31 pm
This being so we must go on to try to explain why the sea is salt.
There are many facts which make it clear that this taste is due to
the admixture of something. First, in animal bodies what is least
digested, the residue of liquid food, is salt and bitter, as we said
before. All animal excreta are undigested, but especially that which
gathers in the bladder (its extreme lightness proves this; for everything
that is digested is condensed), and also sweat; in these then is excreted
(along with other matter) an identical substance to which this flavour
is due. The case of things burnt is analogous. What heat fails to
assimilate becomes the excrementary residue in animal bodies, and,
in things burnt, ashes. That is why some people say that it was burnt
earth that made the sea salt. To say that it was burnt earth is absurd;
but to say that it was something like burnt earth is true. We must
suppose that just as in the cases we have described, so in the world
as a whole, everything that grows and is naturally generated always
leaves an undigested residue, like that of things burnt, consisting
of this sort of earth. All the earthy stuff in the dry exhalation
is of this nature, and it is the dry exhalation which accounts for
its great quantity. Now since, as we have said, the moist and the
dry evaporations are mixed, some quantity of this stuff must always
be included in the clouds and the water that are formed by condensation,
and must redescend to the earth in rain. This process must always
go on with such regularity as the sublunary world admits of. and it
is the answer to the question how the sea comes to be salt.

It also explains why rain that comes from the south, and the first
rains of autumn, are brackish. The south is the warmest of winds and
it blows from dry and hot regions. Hence it carries little moist vapour
and that is why it is hot. (It makes no difference even if this is
not its true character and it is originally a cold wind, for it becomes
warm on its way by incorporating with itself a great quantity of dry
evaporation from the places it passes over.) The north wind, on the
other hand, comb ing from moist regions, is full of vapour and therefore
cold. It is dry in our part of the world because it drives the clouds
away before it, but in the south it is rainy; just as the south is
a dry wind in Libya. So the south wind charges the rain that falls
with a great quantity of this stuff. Autumn rain is brackish because
the heaviest water must fall first; so that that which contains the
greatest quantity of this kind of earth descends quickest.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:48:45 pm
This, too, is why the sea is warm. Everything that has been exposed
to fire contains heat potentially, as we see in the case of lye and
ashes and the dry and liquid excreta of animals. Indeed those animals
which are hottest in the belly have the hottest excreta.

The action of this cause is continually making the sea more salt,
but some part of its saltness is always being drawn up with the sweet
water. This is less than the sweet water in the same ratio in which
the salt and brackish element in rain is less than the sweet, and
so the saltness of the sea remains constant on the whole. Salt water
when it turns into vapour becomes sweet, and the vapour does not form
salt water when it condenses again. This I know by experiment. The
same thing is true in every case of the kind: wine and all fluids
that evaporate and condense back into a liquid state become water.
They all are water modified by a certain admixture, the nature of
which determines their flavour. But this subject must be considered
on another more suitable occasion.

For the present let us say this. The sea is there and some of it is
continually being drawn up and becoming sweet; this returns from above
with the rain. But it is now different from what it was when it was
drawn up, and its weight makes it sink below the sweet water. This
process prevents the sea, as it does rivers, from drying up except
from local causes (this must happen to sea and rivers alike). On the
other hand the parts neither of the earth nor of the sea remain constant
but only their whole bulk. For the same thing is true of the earth
as of the sea: some of it is carried up and some comes down with the
rain, and both that which remains on the surface and that which comes
down again change their situations.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:48:57 pm
There is more evidence to prove that saltness is due to the admixture
of some substance, besides that which we have adduced. Make a vessel
of wax and put it in the sea, fastening its mouth in such a way as
to prevent any water getting in. Then the water that percolates through
the wax sides of the vessel is sweet, the earthy stuff, the admixture
of which makes the water salt, being separated off as it were by a
filter. It is this stuff which make salt water heavy (it weighs more
than fresh water) and thick. The difference in consistency is such
that ships with the same cargo very nearly sink in a river when they
are quite fit to navigate in the sea. This circumstance has before
now caused loss to shippers freighting their ships in a river. That
the thicker consistency is due to an admixture of something is proved
by the fact that if you make strong brine by the admixture of salt,
eggs, even when they are full, float in it. It almost becomes like
mud; such a quantity of earthy matter is there in the sea. The same
thing is done in salting fish.

Again if, as is fabled, there is a lake in Palestine, such that if
you bind a man or beast and throw it in it floats and does not sink,
this would bear out what we have said. They say that this lake is
so bitter and salt that no fish live in it and that if you soak clothes
in it and shake them it cleans them. The following facts all of them
support our theory that it is some earthy stuff in the water which
makes it salt. In Chaonia there is a spring of brackish water that
flows into a neighbouring river which is sweet but contains no fish.
The local story is that when Heracles came from Erytheia driving the
oxen and gave the inhabitants the choice, they chose salt in preference
to fish. They get the salt from the spring. They boil off some of
the water and let the rest stand; when it has cooled and the heat
and moisture have evaporated together it gives them salt, not in lumps
but loose and light like snow. It is weaker than ordinary salt and
added freely gives a sweet taste, and it is not as white as salt generally
is. Another instance of this is found in Umbria. There is a place
there where reeds and rushes grow. They burn some of these, put the
ashes into water and boil it off. When a little water is left and
has cooled it gives a quantity of salt.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:49:10 pm
Most salt rivers and springs must once have been hot. Then the original
fire in them was extinguished but the earth through which they percolate
preserves the character of lye or ashes. Springs and rivers with all
kinds of flavours are found in many places. These flavours must in
every case be due to the fire that is or was in them, for if you expose
earth to different degrees of heat it assumes various kinds and shades
of flavour. It becomes full of alum and lye and other things of the
kind, and the fresh water percolates through these and changes its
character. Sometimes it becomes acid as in Sicania, a part of Sicily.
There they get a salt and acid water which they use as vinegar to
season some of their dishes. In the neighbourhood of Lyncus, too,
there is a spring of acid water, and in Scythia a bitter spring. The
water from this makes the whole of the river into which it flows bitter.
These differences are explained by a knowledge of the particular mixtures
that determine different savours. But these have been explained in
another treatise.

We have now given an account of waters and the sea, why they persist,
how they change, what their nature is, and have explained most of
their natural operations and affections.

Part 4

Let us proceed to the theory of winds. Its basis is a distinction
we have already made. We recognize two kinds of evaporation, one moist,
the other dry. The former is called vapour: for the other there is
no general name but we must call it a sort of smoke, applying to the
whole of it a word that is proper to one of its forms. The moist cannot
exist without the dry nor the dry without the moist: whenever we speak
of either we mean that it predominates. Now when the sun in its circular
course approaches, it draws up by its heat the moist evaporation:
when it recedes the cold makes the vapour that had been raised condense
back into water which falls and is distributed through the earth.
(This explains why there is more rain in winter and more by night
than by day: though the fact is not recognized because rain by night
is more apt to escape observation than by day.) But there is a great
quantity of fire and heat in the earth, and the sun not only draws
up the moisture that lies on the surface of it, but warms and dries
the earth itself. Consequently, since there are two kinds of evaporation,
as we have said, one like vapour, the other like smoke, both of them
are necessarily generated. That in which moisture predominates is
the source of rain, as we explained before, while the dry evaporation
is the source and substance of all winds. That things must necessarily
take this course is clear from the resulting phenomena themselves,
for the evaporation that is to produce them must necessarily differ;
and the sun and the warmth in the earth not only can but must produce
these evaporations.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:49:21 pm
Since the two evaporations are specifically distinct, wind and rain
obviously differ and their substance is not the same, as those say
who maintain that one and the same air when in motion is wind, but
when it condenses again is water. Air, as we have explained in an
earlier book, is made up of these as constituents. Vapour is moist
and cold (for its fluidity is due to its moistness, and because it
derives from water it is naturally cold, like water that has not been
warmed): whereas the smoky evaporation is hot and dry. Hence each
contributes a part, and air is moist and hot. It is absurd that this
air that surrounds us should become wind when in motion, whatever
be the source of its motion on the contrary the case of winds is like
that of rivers. We do not call water that flows anyhow a river, even
if there is a great quantity of it, but only if the flow comes from
a spring. So too with the winds; a great quantity of air might be
moved by the fall of some large object without flowing from any source
or spring.

The facts bear out our theory. It is because the evaporation takes
place uninterruptedly but differs in degree and quantity that clouds
and winds appear in their natural proportion according to the season;
and it is because there is now a great excess of the vaporous, now
of the dry and smoky exhalation, that some years are rainy and wet,
others windy and dry. Sometimes there is much drought or rain, and
it prevails over a great and continuous stretch of country. At other
times it is local; the surrounding country often getting seasonable
or even excessive rains while there is drought in a certain part;
or, contrariwise, all the surrounding country gets little or even
no rain while a certain part gets rain in abundance. The reason for
all this is that while the same affection is generally apt to prevail
over a considerable district because adjacent places (unless there
is something special to differentiate them) stand in the same relation
to the sun, yet on occasion the dry evaporation will prevail in one
part and the moist in another, or conversely. Again the reason for
this latter is that each evaporation goes over to that of the neighbouring
district: for instance, the dry evaporation circulates in its own
place while the moist migrates to the next district or is even driven
by winds to some distant place: or else the moist evaporation remains
and the dry moves away. Just as in the case of the body when the stomach
is dry the lower belly is often in the contrary state, and when it
is dry the stomach is moist and cold, so it often happens that the
evaporations reciprocally take one another's place and interchange.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:49:37 pm
Further, after rain wind generally rises in those places where the
rain fell, and when rain has come on the wind ceases. These are necessary
effects of the principles we have explained. After rain the earth
is being dried by its own heat and that from above and gives off the
evaporation which we saw to be the material cause of. wind. Again,
suppose this secretion is present and wind prevails; the heat is continually
being thrown off, rising to the upper region, and so the wind ceases;
then the fall in temperature makes vapour form and condense into water.
Water also forms and cools the dry evaporation when the clouds are
driven together and the cold concentrated in them. These are the causes
that make wind cease on the advent of rain, and rain fall on the cessation
of wind.

The cause of the predominance of winds from the north and from the
south is the same. (Most winds, as a matter of fact, are north winds
or south winds.) These are the only regions which the sun does not
visit: it approaches them and recedes from them, but its course is
always over the-west and the east. Hence clouds collect on either
side, and when the sun approaches it provokes the moist evaporation,
and when it recedes to the opposite side there are storms and rain.
So summer and winter are due to the sun's motion to and from the solstices,
and water ascends and falls again for the same reason. Now since most
rain falls in those regions towards which and from which the sun turns
and these are the north and the south, and since most evaporation
must take place where there is the greatest rainfall, just as green
wood gives most smoke, and since this evaporation is wind, it is natural
that the most and most important winds should come from these quarters.
(The winds from the north are called Boreae, those from the south
Noti.)

The course of winds is oblique: for though the evaporation rises straight
up from the earth, they blow round it because all the surrounding
air follows the motion of the heavens. Hence the question might be
asked whether winds originate from above or from below. The motion
comes from above: before we feel the wind blowing the air betrays
its presence if there are clouds or a mist, for their motion shows
that the wind has begun to blow before it has actually reached us;
and this implies that the source of winds is above. But since wind
is defined as 'a quantity of dry evaporation from the earth moving
round the earth', it is clear that while the origin of the motion
is from above, the matter and the generation of wind come from below.
The oblique movement of the rising evaporation is caused from above:
for the motion of the heavens determines the processes that are at
a distance from the earth, and the motion from below is vertical and
every cause is more active where it is nearest to the effect; but
in its generation and origin wind plainly derives from the earth.

The facts bear out the view that winds are formed by the gradual union
of many evaporations just as rivers derive their sources from the
water that oozes from the earth. Every wind is weakest in the spot
from which it blows; as they proceed and leave their source at a distance
they gather strength. Thus the winter in the north is windless and
calm: that is, in the north itself; but, the breeze that blows from
there so gently as to escape observation becomes a great wind as it
passes on.

We have explained the nature and origin of wind, the occurrence of
drought and rains, the reason why rain stops wind and wind rises after
rain, the prevalence of north and south winds and also why wind moves
in the way it does.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:49:50 pm
Part 5

The sun both checks the formation of winds and stimulates it. When
the evaporation is small in amount and faint the sun wastes it and
dissipates by its greater heat the lesser heat contained in the evaporation.
It also dries up the earth, the source of the evaporation, before
the latter has appeared in bulk: just as, when you throw a little
fuel into a great fire, it is often burnt up before giving off any
smoke. In these ways the sun checks winds and prevents them from rising
at all: it checks them by wasting the evaporation, and prevents their
rising by drying up the earth quickly. Hence calm is very apt to prevail
about the rising of Orion and lasts until the coming of the Etesiae
and their 'forerunners'.

Calm is due to two causes. Either cold quenches the evaporation, for
instance a sharp frost: or excessive heat wastes it. In the intermediate
periods, too, the causes are generally either that the evaporation
has not had time to develop or that it has passed away and there is
none as yet to replace it.

Both the setting and the rising of Orion are considered to be treacherous
and stormy, because they place at a change of season (namely of summer
or winter; and because the size of the constellation makes its rise
last over many days) and a state of change is always indefinite and
therefore liable to disturbance.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:50:05 pm
The Etesiae blow after the summer solstice and the rising of the dog-star:
not at the time when the sun is closest nor when it is distant; and
they blow by day and cease at night. The reason is that when the sun
is near it dries up the earth before evaporation has taken place,
but when it has receded a little its heat and the evaporation are
present in the right proportion; so the ice melts and the earth, dried
by its own heat and that of the sun, smokes and vapours. They abate
at night because the cold pf the nights checks the melting of the
ice. What is frozen gives off no evaporation, nor does that which
contains no dryness at all: it is only where something dry contains
moisture that it gives off evaporation under the influence of heat.

The question is sometimes asked: why do the north winds which we call
the Etesiae blow continuously after the summer solstice, when there
are no corresponding south winds after the winter solstice? The facts
are reasonable enough: for the so-called 'white south winds' do blow
at the corresponding season, though they are not equally continuous
and so escape observation and give rise to this inquiry. The reason
for this is that the north wind I from the arctic regions which are
full of water and snow. The sun thaws them and so the Etesiae blow:
after rather than at the summer solstice. (For the greatest heat is
developed not when the sun is nearest to the north, but when its heat
has been felt for a considerable period and it has not yet receded
far. The 'bird winds' blow in the same way after the winter solstice.
They, too, are weak Etesiae, but they blow less and later than the
Etesiae. They begin to blow only on the seventieth day because the
sun is distant and therefore weaker. They do not blow so continuously
because only things on the surface of the earth and offering little
resistance evaporate then, the thoroughly frozen parts requiring greater
heat to melt them. So they blow intermittently till the true Etesiae
come on again at the summer solstice: for from that time onwards the
wind tends to blow continuously.) But the south wind blows from the
tropic of Cancer and not from the antarctic region.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:50:22 pm
There are two inhabitable sections of the earth: one near our upper,
or nothern pole, the other near the other or southern pole; and their
shape is like that of a tambourine. If you draw lines from the centre
of the earth they cut out a drum-shaped figure. The lines form two
cones; the base of the one is the tropic, of the other the ever visible
circle, their vertex is at the centre of the earth. Two other cones
towards the south pole give corresponding segments of the earth. These
sections alone are habitable. Beyond the tropics no one can live:
for there the shade would not fall to the north, whereas the earth
is known to be uninhabitable before the sun is in the zenith or the
shade is thrown to the south: and the regions below the Bear are uninhabitable
because of the cold.

(The Crown, too, moves over this region: for it is in the zenith when
it is on our meridian.)

So we see that the way in which they now describe the geography of
the earth is ridiculous. They depict the inhabited earth as round,
but both ascertained facts and general considerations show this to
be impossible. If we reflect we see that the inhabited region is limited
in breadth, while the climate admits of its extending all round the
earth. For we meet with no excessive heat or cold in the direction
of its length but only in that of its breadth; so that there is nothing
to prevent our travelling round the earth unless the extent of the
sea presents an obstacle anywhere. The records of journeys by sea
and land bear this out. They make the length far greater than the
breadth. If we compute these voyages and journeys the distance from
the Pillars of Heracles to India exceeds that from Aethiopia to Maeotis
and the northernmost Scythians by a ratio of more than 5 to 3, as
far as such matters admit of accurate statement. Yet we know the whole
breadth of the region we dwell in up to the uninhabited parts: in
one direction no one lives because of the cold, in the other because
of the heat.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:50:37 pm
But it is the sea which divides as it seems the parts beyond India
from those beyond the Pillars of Heracles and prevents the earth from
being inhabited all round.

Now since there must be a region bearing the same relation to the
southern pole as the place we live in bears to our pole, it will clearly
correspond in the ordering of its winds as well as in other things.
So just as we have a north wind here, they must have a corresponding
wind from the antarctic. This wind cannot reach us since our own north
wind is like a land breeze and does not even reach the limits of the
region we live in. The prevalence of north winds here is due to our
lying near the north. Yet even here they give out and fail to penetrate
far: in the southern sea beyond Libya east and west winds are always
blowing alternately, like north and south winds with us. So it is
clear that the south wind is not the wind that blows from the south
pole. It is neither that nor the wind from the winter tropic. For
symmetry would require another wind blowing from the summer tropic,
which there is not, since we know that only one wind blows from that
quarter. So the south wind clearly blows from the torrid region. Now
the sun is so near to that region that it has no water, or snow which
might melt and cause Etesiae. But because that place is far more extensive
and open the south wind is greater and stronger and warmer than the
north and penetrates farther to the north than the north wind does
to the south.

The origin of these winds and their relation to one another has now
been explained.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:50:53 pm
Part 6

Let us now explain the position of the winds, their oppositions, which
can blow simultaneously with which, and which cannot, their names
and number, and any other of their affections that have not been treated
in the 'particular questions'. What we say about their position must
be followed with the help of the figure. For clearness' sake we have
drawn the circle of the horizon, which is round, but it represents
the zone in which we live; for that can be divided in the same way.
Let us also begin by laying down that those things are locally contrary
which are locally most distant from one another, just as things specifically
most remote from one another are specific contraries. Now things that
face one another from opposite ends of a diameter are locally most
distant from one another. (See diagram.)

Let A be the point where the sun sets at the equinox and B, the point
opposite, the place where it rises at the equinox. Let there be another
diameter cutting this at right angles, and let the point H on it be
the north and its diametrical opposite O the south. Let Z be the rising
of the sun at the summer solstice and E its setting at the summer
solstice; D its rising at the winter solstice, and G its setting at
the winter solstice. Draw a diameter from Z to G from D to E. Then
since those things are locally contrary which are most distant from
one another in space, and points diametrically opposite are most distant
from one another, those winds must necessarily be contrary to one
another that blow from opposite ends of a diameter.

The names of the winds according to their position are these. Zephyrus
is the wind that blows from A, this being the point where the sun
sets at the equinox. Its contrary is Apeliotes blowing from B the
point where the sun rises at the equinox. The wind blowing from H,
the north, is the true north wind, called Aparctias: while Notus blowing
from O is its contrary; for this point is the south and O is contrary
to H, being diametrically opposite to it. Caecias blows from Z, where
the sun rises at the summer solstice. Its contrary is not the wind
blowing from E but Lips blowing from G. For Lips blows from the point
where the sun sets at the winter solstice and is diametrically opposite
to Caecias: so it is its contrary. Eurus blows from D, coming from
the point where the sun rises at the winter solstice. It borders on
Notus, and so we often find that people speak of 'Euro-Noti'. Its
contrary is not Lips blowing from G but the wind that blows from E
which some call Argestes, some Olympias, and some Sciron. This blows
from the point where the sun sets at the summer solstice, and is the
only wind that is diametrically opposite to Eurus. These are the winds
that are diametrically opposite to one another and their contraries.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:51:09 pm
There are other winds which have no contraries. The wind they call
Thrascias, which lies between Argestes and Aparctias, blows from I;
and the wind called Meses, which lies between Caecias and Aparctias,
from K. (The line IK nearly coincides with the ever visible circle,
but not quite.) These winds have no contraries. Meses has not, or
else there would be a wind blowing from the point M which is diametrically
opposite. Thrascias corresponding to the point I has not, for then
there would be a wind blowing from N, the point which is diametrically
opposite. (But perhaps a local wind which the inhabitants of those
parts call Phoenicias blows from that point.)

These are the most important and definite winds and these their places.

There are more winds from the north than from the south. The reason
for this is that the region in which we live lies nearer to the north.
Also, much more water and snow is pushed aside into this quarter because
the other lies under the sun and its course. When this thaws and soaks
into the earth and is exposed to the heat of the sun and the earth
it necessarily causes evaporation to rise in greater quantities and
over a greater space.

Of the winds we have described Aparctias is the north wind in the
strict sense. Thrascias and Meses are north winds too. (Caecias is
half north and half east.) South are that which blows from due south
and Lips. East, the wind from the rising of the sun at the equinox
and Eurus. Phoenicias is half south and half east. West, the wind
from the true west and that called Argestes. More generally these
winds are classified as northerly or southerly. The west winds are
counted as northerly, for they blow from the place of sunset and are
therefore colder; the east winds as southerly, for they are warmer
because they blow from the place of sunrise. So the distinction of
cold and hot or warm is the basis for the division of the winds into
northerly and southerly. East winds are warmer than west winds because
the sun shines on the east longer, whereas it leaves the west sooner
and reaches it later.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:51:21 pm
Since this is the distribution of the winds it is clear that contrary
winds cannot blow simultaneously. They are diametrically opposite
to one another and one of the two must be overpowered and cease. Winds
that are not diametrically opposite to one another may blow simultaneously:
for instance the winds from Z and from D. Hence it sometimes happens
that both of them, though different winds and blowing from different
quarters, are favourable to sailors making for the same point.

Contrary winds commonly blow at opposite seasons. Thus Caecias and
in general the winds north of the summer solstice blow about the time
of the spring equinox, but about the autumn equinox Lips; and Zephyrus
about the summer solstice, but about the winter solstice Eurus.

Aparctias, Thrascias, and Argestes are the winds that fall on others
most and stop them. Their source is so close to us that they are greater
and stronger than other winds. They bring fair weather most of all
winds for the same reason, for, blowing as they do, from close at
hand, they overpower the other winds and stop them; they also blow
away the clouds that are forming and leave a clear sky-unless they
happen to be very cold. Then they do not bring fair weather, but being
colder than they are strong they condense the clouds before driving
them away.

Caecias does not bring fair weather because it returns upon itself.
Hence the saying: 'Bringing it on himself as Caecias does clouds.'

When they cease, winds are succeeded by their neighbours in the direction
of the movement of the sun. For an effect is most apt to be produced
in the neighbourhood of its cause, and the cause of winds moves with
the sun.

Contrary winds have either the same or contrary effects. Thus Lips
and Caecias, sometimes called Hellespontias, are both rainy gestes
and Eurus are dry: the latter being dry at first and rainy afterwards.
Meses and Aparctias are coldest and bring most snow. Aparctias, Thrascias,
and Argestes bring hail. Notus, Zephyrus, and Eurus are hot. Caecias
covers the sky with heavy clouds, Lips with lighter ones. Caecias
does this because it returns upon itself and combines the qualities
of Boreas and Eurus. By being cold it condenses and gathers the vaporous
air, and because it is easterly it carries with it and drives before
it a great quantity of such matter. Aparctias, Thrascias, and Argestes
bring fair weather for the reason we have explained before. These
winds and Meses are most commonly accompanied by lightning. They are
cold because they blow from the north, and lightning is due to cold,
being ejected when the clouds contract. Some of these same bring hail
with them for the same reason; namely, that they cause a sudden condensation.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:51:33 pm
Hurricanes are commonest in autumn, and next in spring: Aparctias,
Thrascias, and Argestes give rise to them most. This is because hurricanes
are generally formed when some winds are blowing and others fall on
them; and these are the winds which are most apt to fall on others
that are blowing; the reason for which, too, we have explained before.

The Etesiae veer round: they begin from the north, and become for
dwellers in the west Thrasciae, Argestae, and Zephyrus (for Zephyrus
belongs to the north). For dwellers in the east they veer round as
far as Apeliotes.

So much for the winds, their origin and nature and the properties
common to them all or peculiar to each.

Part 7

We must go on to discuss earthquakes next, for their cause is akin
to our last subject.

The theories that have been put forward up to the present date are
three, and their authors three men, Anaxagoras of Clazomenae, and
before him Anaximenes of Miletus, and later Democritus of Abdera.

Anaxagoras says that the ether, which naturally moves upwards, is
caught in hollows below the earth and so shakes it, for though the
earth is really all of it equally porous, its surface is clogged up
by rain. This implies that part of the whole sphere is 'above' and
part 'below': 'above' being the part on which we live, 'below' the
other.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:51:51 pm
This theory is perhaps too primitive to require refutation. It is
absurd to think of up and down otherwise than as meaning that heavy
bodies move to the earth from every quarter, and light ones, such
as fire, away from it; especially as we see that, as far as our knowledge
of the earth goes, the horizon always changes with a change in our
position, which proves that the earth is convex and spherical. It
is absurd, too, to maintain that the earth rests on the air because
of its size, and then to say that impact upwards from below shakes
it right through. Besides he gives no account of the circumstances
attendant on earthquakes: for not every country or every season is
subject to them.

Democritus says that the earth is full of water and that when a quantity
of rain-water is added to this an earthquake is the result. The hollows
in the earth being unable to admit the excess of water it forces its
way in and so causes an earthquake. Or again, the earth as it dries
draws the water from the fuller to the emptier parts, and the inrush
of the water as it changes its place causes the earthquake.

Anaximenes says that the earth breaks up when it grows wet or dry,
and earthquakes are due to the fall of these masses as they break
away. Hence earthquakes take place in times of drought and again of
heavy rain, since, as we have explained, the earth grows dry in time
of drought and breaks up, whereas the rain makes it sodden and destroys
its cohesion.

But if this were the case the earth ought to be found to be sinking
in many places. Again, why do earthquakes frequently occur in places
which are not excessively subject to drought or rain, as they ought
to be on the theory? Besides, on this view, earthquakes ought always
to be getting fewer, and should come to an end entirely some day:
the notion of contraction by packing together implies this. So this
is impossible the theory must be impossible too.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:52:18 pm
Part 8

We have already shown that wet and dry must both give rise to an evaporation:
earthquakes are a necessary consequence of this fact. The earth is
essentially dry, but rain fills it with moisture. Then the sun and
its own fire warm it and give rise to a quantity of wind both outside
and inside it. This wind sometimes flows outwards in a single body,
sometimes inwards, and sometimes it is divided. All these are necessary
laws. Next we must find out what body has the greatest motive force.
This will certainly be the body that naturally moves farthest and
is most violent. Now that which has the most rapid motion is necessarily
the most violent; for its swiftness gives its impact the greatest
force. Again, the rarest body, that which can most readily pass through
every other body, is that which naturally moves farthest. Wind satisfies
these conditions in the highest degree (fire only becomes flame and
moves rapidly when wind accompanies it): so that not water nor earth
is the cause of earthquakes but wind-that is, the inrush of the external
evaporation into the earth.

Hence, since the evaporation generally follows in a continuous body
in the direction in which it first started, and either all of it flows
inwards or all outwards, most earthquakes and the greatest are accompanied
by calm. It is true that some take place when a wind is blowing, but
this presents no difficulty. We sometimes find several winds blowing
simultaneously. If one of these enters the earth we get an earthquake
attended by wind. Only these earthquakes are less severe because their
source and cause is divided.

Again, most earthquakes and the severest occur at night or, if by
day, about noon, that being generally the calmest part of the day.
For when the sun exerts its full power (as it does about noon) it
shuts the evaporation into the earth. Night, too, is calmer than day.
The absence of the sun makes the evaporation return into the earth
like a sort of ebb tide, corresponding to the outward flow; especially
towards dawn, for the winds, as a rule, begin to blow then, and if
their source changes about like the Euripus and flows inwards the
quantity of wind in the earth is greater and a more violent earthquake
results.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:52:35 pm
The severest earthquakes take place where the sea is full of currents
or the earth spongy and cavernous: so they occur near the Hellespont
and in Achaea and Sicily, and those parts of Euboea which correspond
to our description-where the sea is supposed to flow in channels below
the earth. The hot springs, too, near Aedepsus are due to a cause
of this kind. It is the confined character of these places that makes
them so liable to earthquakes. A great and therefore violent wind
is developed, which would naturally blow away from the earth: but
the onrush of the sea in a great mass thrusts it back into the earth.
The countries that are spongy below the surface are exposed to earthquakes
because they have room for so much wind.

For the same reason earthquakes usually take place in spring and autumn
and in times of wet and of drought-because these are the windiest
seasons. Summer with its heat and winter with its frost cause calm:
winter is too cold, summer too dry for winds to form. In time of drought
the air is full of wind; drought is just the predominance of the dry
over the moist evaporation. Again, excessive rain causes more of the
evaporation to form in the earth. Then this secretion is shut up in
a narrow compass and forced into a smaller space by the water that
fills the cavities. Thus a great wind is compressed into a smaller
space and so gets the upper hand, and then breaks out and beats against
the earth and shakes it violently.

We must suppose the action of the wind in the earth to be analogous
to the tremors and throbbings caused in us by the force of the wind
contained in our bodies. Thus some earthquakes are a sort of tremor,
others a sort of throbbing. Again, we must think of an earthquake
as something like the tremor that often runs through the body after
passing water as the wind returns inwards from without in one volume.

The force wind can have may be gathered not only from what happens
in the air (where one might suppose that it owed its power to produce
such effects to its volume), but also from what is observed in animal
bodies. Tetanus and spasms are motions of wind, and their force is
such that the united efforts of many men do not succeed in overcoming
the movements of the patients. We must suppose, then (to compare great
things with small), that what happens in the earth is just like that.
Our theory has been verified by actual observation in many places.
It has been known to happen that an earthquake has continued until
the wind that caused it burst through the earth into the air and appeared
visibly like a hurricane. This happened lately near Heracleia in Pontus
and some time past at the island Hiera, one of the group called the
Aeolian islands. Here a portion of the earth swelled up and a lump
like a mound rose with a noise: finally it burst, and a great wind
came out of it and threw up live cinders and ashes which buried the
neighbouring town of Lipara and reached some of the towns in Italy.
The spot where this eruption occurred is still to be seen.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:52:48 pm
Indeed, this must be recognized as the cause of the fire that is generated
in the earth: the air is first broken up in small particles and then
the wind is beaten about and so catches fire.

A phenomenon in these islands affords further evidence of the fact
that winds move below the surface of the earth. When a south wind
is going to blow there is a premonitory indication: a sound is heard
in the places from which the eruptions issue. This is because the
sea is being pushed on from a distance and its advance thrusts back
into the earth the wind that was issuing from it. The reason why there
is a noise and no earthquake is that the underground spaces are so
extensive in proportion to the quantity of the air that is being driven
on that the wind slips away into the void beyond.

Again, our theory is supported by the facts that the sun appears hazy
and is darkened in the absence of clouds, and that there is sometimes
calm and sharp frost before earthquakes at sunrise. The sun is necessarily
obscured and darkened when the evaporation which dissolves and rarefies
the air begins to withdraw into the earth. The calm, too, and the
cold towards sunrise and dawn follow from the theory. The calm we
have already explained. There must as a rule be calm because the wind
flows back into the earth: again, it must be most marked before the
more violent earthquakes, for when the wind is not part outside earth,
part inside, but moves in a single body, its strength must be greater.
The cold comes because the evaporation which is naturally and essentially
hot enters the earth. (Wind is not recognized to be hot, because it
sets the air in motion, and that is full of a quantity of cold vapour.
It is the same with the breath we blow from our mouth: close by it
is warm, as it is when we breathe out through the mouth, but there
is so little of it that it is scarcely noticed, whereas at a distance
it is cold for the same reason as wind.) Well, when this evaporation
disappears into the earth the vaporous exhalation concentrates and
causes cold in any place in which this disappearance occurs.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:53:04 pm
A sign which sometimes precedes earthquakes can be explained in the
same way. Either by day or a little after sunset, in fine weather,
a little, light, long-drawn cloud is seen, like a long very straight
line. This is because the wind is leaving the air and dying down.
Something analogous to this happens on the sea-shore. When the sea
breaks in great waves the marks left on the sand are very thick and
crooked, but when the sea is calm they are slight and straight (because
the secretion is small). As the sea is to the shore so the wind is
to the cloudy air; so, when the wind drops, this very straight and
thin cloud is left, a sort of wave-mark in the air.

An earthquake sometimes coincides with an eclipse of the moon for
the same reason. When the earth is on the point of being interposed,
but the light and heat of the sun has not quite vanished from the
air but is dying away, the wind which causes the earthquake before
the eclipse, turns off into the earth, and calm ensues. For there
often are winds before eclipses: at nightfall if the eclipse is at
midnight, and at midnight if the eclipse is at dawn. They are caused
by the lessening of the warmth from the moon when its sphere approaches
the point at which the eclipse is going to take place. So the influence
which restrained and quieted the air weakens and the air moves again
and a wind rises, and does so later, the later the eclipse.

A severe earthquake does not stop at once or after a single shock,
but first the shocks go on, often for about forty days; after that,
for one or even two years it gives premonitory indications in the
same place. The severity of the earthquake is determined by the quantity
of wind and the shape of the passages through which it flows. Where
it is beaten back and cannot easily find its way out the shocks are
most violent, and there it must remain in a cramped space like water
that cannot escape. Any throbbing in the body does not cease suddenly
or quickly, but by degrees according as the affection passes off.
So here the agency which created the evaporation and gave it an impulse
to motion clearly does not at once exhaust the whole of the material
from which it forms the wind which we call an earthquake. So until
the rest of this is exhausted the shocks must continue, though more
gently, and they must go on until there is too little of the evaporation
left to have any perceptible effect on the earth at all.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 30, 2009, 11:53:30 pm
Subterranean noises, too, are due to the wind; sometimes they portend
earthquakes but sometimes they have been heard without any earthquake
following. Just as the air gives off various sounds when it is struck,
so it does when it strikes other things; for striking involves being
struck and so the two cases are the same. The sound precedes the shock
because sound is thinner and passes through things more readily than
wind. But when the wind is too weak by reason of thinness to cause
an earthquake the absence of a shock is due to its filtering through
readily, though by striking hard and hollow masses of different shapes
it makes various noises, so that the earth sometimes seems to 'bellow'
as the portentmongers say.

Water has been known to burst out during an earthquake. But that does
not make water the cause of the earthquake. The wind is the efficient
cause whether it drives the water along the surface or up from below:
just as winds are the causes of waves and not waves of winds. Else
we might as well say that earth was the cause; for it is upset in
an earthquake, just like water (for effusion is a form of upsetting).
No, earth and water are material causes (being patients, not agents):
the true cause is the wind.

The combination of a tidal wave with an earthquake is due to the presence
of contrary winds. It occurs when the wind which is shaking the earth
does not entirely succeed in driving off the sea which another wind
is bringing on, but pushes it back and heaps it up in a great mass
in one place. Given this situation it follows that when this wind
gives way the whole body of the sea, driven on by the other wind,
will burst out and overwhelm the land. This is what happened in Achaea.
There a south wind was blowing, but outside a north wind; then there
was a calm and the wind entered the earth, and then the tidal wave
came on and simultaneously there was an earthquake. This was the more
violent as the sea allowed no exit to the wind that had entered the
earth, but shut it in. So in their struggle with one another the wind
caused the earthquake, and the wave by its settling down the inundation.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:01:14 am
Earthquakes are local and often affect a small district only; whereas
winds are not local. Such phenomena are local when the evaporations
at a given place are joined by those from the next and unite; this,
as we explained, is what happens when there is drought or excessive
rain locally. Now earthquakes do come about in this way but winds
do not. For earthquakes, rains, and droughts have their source and
origin inside the earth, so that the sun is not equally able to direct
all the evaporations in one direction. But on the evaporations in
the air the sun has more influence so that, when once they have been
given an impulse by its motion, which is determined by its various
positions, they flow in one direction.

When the wind is present in sufficient quantity there is an earthquake.
The shocks are horizontal like a tremor; except occasionally, in a
few places, where they act vertically, upwards from below, like a
throbbing. It is the vertical direction which makes this kind of earthquake
so rare. The motive force does not easily accumulate in great quantity
in the position required, since the surface of the earth secretes
far more of the evaporation than its depths. Wherever an earthquake
of this kind does occur a quantity of stones comes to the surface
of the earth (as when you throw up things in a winnowing fan), as
we see from Sipylus and the Phlegraean plain and the district in Liguria,
which were devastated by this kind of earthquake.

Islands in the middle of the sea are less exposed to earthquakes than
those near land. First, the volume of the sea cools the evaporations
and overpowers them by its weight and so crushes them. Then, currents
and not shocks are produced in the sea by the action of the winds.
Again, it is so extensive that evaporations do not collect in it but
issue from it, and these draw the evaporations from the earth after
them. Islands near the continent really form part of it: the intervening
sea is not enough to make any difference; but those in the open sea
can only be shaken if the whole of the sea that surrounds them is
shaken too.

We have now explained earthquakes, their nature and cause, and the
most important of the circumstances attendant on their appearance.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:01:33 am
Part 9

Let us go on to explain lightning and thunder, and further whirlwind,
fire-wind, and thunderbolts: for the cause of them all is the same.

As we have said, there are two kinds of exhalation, moist and dry,
and the atmosphere contains them both potentially. It, as we have
said before, condenses into cloud, and the density of the clouds is
highest at their upper limit. (For they must be denser and colder
on the side where the heat escapes to the upper region and leaves
them. This explains why hurricanes and thunderbolts and all analogous
phenomena move downwards in spite of the fact that everything hot
has a natural tendency upwards. Just as the pips that we squeeze between
our fingers are heavy but often jump upwards: so these things are
necessarily squeezed out away from the densest part of the cloud.)
Now the heat that escapes disperses to the up region. But if any of
the dry exhalation is caught in the process as the air cools, it is
squeezed out as the clouds contract, and collides in its rapid course
with the neighbouring clouds, and the sound of this collision is what
we call thunder. This collision is analogous, to compare small with
great, to the sound we hear in a flame which men call the laughter
or the threat of Hephaestus or of Hestia. This occurs when the wood
dries and cracks and the exhalation rushes on the flame in a body.
So in the clouds, the exhalation is projected and its impact on dense
clouds causes thunder: the variety of the sound is due to the irregularity
of the clouds and the hollows that intervene where their density is
interrupted. This then, is thunder, and this its cause.

It usually happens that the exhalation that is ejected is inflamed
and burns with a thin and faint fire: this is what we call lightning,
where we see as it were the exhalation coloured in the act of its
ejection. It comes into existence after the collision and the thunder,
though we see it earlier because sight is quicker than hearing. The
rowing of triremes illustrates this: the oars are going back again
before the sound of their striking the water reaches us.

However, there are some who maintain that there is actually fire in
the clouds. Empedocles says that it consists of some of the sun's
rays which are intercepted: Anaxagoras that it is part of the upper
ether (which he calls fire) which has descended from above. Lightning,
then, is the gleam of this fire, and thunder the hissing noise of
its extinction in the cloud.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:01:49 am
But this involves the view that lightning actually is prior to thunder
and does not merely appear to be so. Again, this intercepting of the
fire is impossible on either theory, but especially it is said to
be drawn down from the upper ether. Some reason ought to be given
why that which naturally ascends should descend, and why it should
not always do so, but only when it is cloudy. When the sky is clear
there is no lightning: to say that there is, is altogether wanton.

The view that the heat of the sun's rays intercepted in the clouds
is the cause of these phenomena is equally unattractive: this, too,
is a most careless explanation. Thunder, lightning, and the rest must
have a separate and determinate cause assigned to them on which they
ensue. But this theory does nothing of the sort. It is like supposing
that water, snow, and hail existed all along and were produced when
the time came and not generated at all, as if the atmosphere brought
each to hand out of its stock from time to time. They are concretions
in the same way as thunder and lightning are discretions, so that
if it is true of either that they are not generated but pre-exist,
the same must be true of the other. Again, how can any distinction
be made about the intercepting between this case and that of interception
in denser substances such as water? Water, too, is heated by the sun
and by fire: yet when it contracts again and grows cold and freezes
no such ejection as they describe occurs, though it ought on their
the. to take place on a proportionate scale. Boiling is due to the
exhalation generated by fire: but it is impossible for it to exist
in the water beforehand; and besides they call the noise 'hissing',
not 'boiling'. But hissing is really boiling on a small scale: for
when that which is brought into contact with moisture and is in process
of being extinguished gets the better of it, then it boils and makes
the noise in question. Some-Cleidemus is one of them-say that lightning
is nothing objective but merely an appearance. They compare it to
what happens when you strike the sea with a rod by night and the water
is seen to shine. They say that the moisture in the cloud is beaten
about in the same way, and that lightning is the appearance of brightness
that ensues.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:02:08 am
This theory is due to ignorance of the theory of reflection, which
is the real cause of that phenomenon. The water appears to shine when
struck because our sight is reflected from it to some bright object:
hence the phenomenon occurs mainly by night: the appearance is not
seen by day because the daylight is too in, tense and obscures it.

These are the theories of others about thunder and lightning: some
maintaining that lightning is a reflection, the others that lightning
is fire shining through the cloud and thunder its extinction, the
fire not being generated in each case but existing beforehand. We
say that the same stuff is wind on the earth, and earthquake under
it, and in the clouds thunder. The essential constituent of all these
phenomena is the same: namely, the dry exhalation. If it flows in
one direction it is wind, in another it causes earthquakes; in the
clouds, when they are in a process of change and contract and condense
into water, it is ejected and causes thunder and lightning and the
other phenomena of the same nature.

So much for thunder and lightning.

----------------------------------------------------------------------


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:02:22 am
BOOK III

Part 1

Let us explain the remaining operations of this secretion in the
same way as we have treated the rest. When this exhalation is secreted
in small and scattered quantities and frequently, and is transitory,
and its constitution rare, it gives rise to thunder and lightning.
But if it is secreted in a body and is denser, that is, less rare,
we get a hurricane. The fact that it issues in body explains its violence:
it is due to the rapidity of the secretion. Now when this secretion
issues in a great and continuous current the result corresponds to
what we get when the opposite development takes place and rain and
a quantity of water are produced. As far as the matter from which
they are developed goes both sets of phenomena are the same. As soon
as a stimulus to the development of either potentiality appears, that
of which there is the greater quantity present in the cloud is at
once secreted from it, and there results either rain, or, if the other
exhalation prevails, a hurricane.

Sometimes the exhalation in the cloud, when it is being secreted,
collides with another under circumstances like those found when a
wind is forced from an open into a narrow space in a gateway or a
road. It often happens in such cases that the first part of the moving
body is deflected because of the resistance due either to the narrowness
or to a contrary current, and so the wind forms a circle and eddy.
It is prevented from advancing in a straight line: at the same time
it is pushed on from behind; so it is compelled to move sideways in
the direction of least resistance. The same thing happens to the next
part, and the next, and so on, till the series becomes one, that is,
till a circle is formed: for if a figure is described by a single
motion that figure must itself be one. This is how eddies are generated
on the earth, and the case is the same in the clouds as far as the
beginning of them goes. Only here (as in the case of the hurricane
which shakes off the cloud without cessation and becomes a continuous
wind) the cloud follows the exhalation unbroken, and the exhalation,
failing to break away from the cloud because of its density, first
moves in a circle for the reason given and then descends, because
clouds are always densest on the side where the heat escapes. This
phenomenon is called a whirlwind when it is colourless; and it is
a sort of undigested hurricane. There is never a whirlwind when the
weather is northerly, nor a hurricane when there is snow. The reason
is that all these phenomena are 'wind', and wind is a dry and warm
evaporation. Now frost and cold prevail over this principle and quench
it at its birth: that they do prevail is clear or there could be no
snow or northerly rain, since these occur when the cold does prevail.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:02:48 am
So the whirlwind originates in the failure of an incipient hurricane
to escape from its cloud: it is due to the resistance which generates
the eddy, and it consists in the spiral which descends to the earth
and drags with it the cloud which it cannot shake off. It moves things
by its wind in the direction in which it is blowing in a straight
line, and whirls round by its circular motion and forcibly snatches
up whatever it meets.

When the cloud burns as it is drawn downwards, that is, when the exhalation
becomes rarer, it is called a fire-wind, for its fire colours the
neighbouring air and inflames it.

When there is a great quantity of exhalation and it is rare and is
squeezed out in the cloud itself we get a thunderbolt. If the exhalation
is exceedingly rare this rareness prevents the thunderbolt from scorching
and the poets call it 'bright': if the rareness is less it does scorch
and they call it 'smoky'. The former moves rapidly because of its
rareness, and because of its rapidity passes through an object before
setting fire to it or dwelling on it so as to blacken it: the slower
one does blacken the object, but passes through it before it can actually
burn it. Further, resisting substances are affected, unresisting ones
are not. For instance, it has happened that the bronze of a shield
has been melted while the woodwork remained intact because its texture
was so loose that the exhalation filtered through without affecting
it. So it has passed through clothes, too, without burning them, and
has merely reduced them to shreds.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:03:02 am
Such evidence is enough by itself to show that the exhalation is at
work in all these cases, but we sometimes get direct evidence as well,
as in the case of the conflagration of the temple at Ephesus which
we lately witnessed. There independent sheets of flame left the main
fire and were carried bodily in many directions. Now that smoke is
exhalation and that smoke burns is certain, and has been stated in
another place before; but when the flame moves bodily, then we have
ocular proof that smoke is exhalation. On this occasion what is seen
in small fires appeared on a much larger scale because of the quantity
of matter that was burning. The beams which were the source of the
exhalation split, and a quantity of it rushed in a body from the place
from which it issued forth and went up in a blaze: so that the flame
was actually seen moving through the air away and falling on the houses.
For we must recognize that exhalation accompanies and precedes thunderbolts
though it is colourless and so invisible. Hence, where the thunderbolt
is going to strike, the object moves before it is struck, showing
that the exhalation leads the way and falls on the object first. Thunder,
too, splits things not by its noise but because the exhalation that
strikes the object and that which makes the noise are ejected simultaneously.
This exhalation splits the thing it strikes but does not scorch it
at all.

We have now explained thunder and lightning and hurricane, and further
firewinds, whirlwinds, and thunderbolts, and shown that they are all
of them forms of the same thing and wherein they all differ.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:03:16 am
Part 2

Let us now explain the nature and cause of halo, rainbow, mock suns,
and rods, since the same account applies to them all.

We must first describe the phenomena and the circumstances in which
each of them occurs. The halo often appears as a complete circle:
it is seen round the sun and the moon and bright stars, by night as
well as by day, and at midday or in the afternoon, more rarely about
sunrise or sunset.

The rainbow never forms a full circle, nor any segment greater than
a semicircle. At sunset and sunrise the circle is smallest and the
segment largest: as the sun rises higher the circle is larger and
the segment smaller. After the autumn equinox in the shorter days
it is seen at every hour of the day, in the summer not about midday.
There are never more than two rainbows at one time. Each of them is
three-coloured; the colours are the same in both and their number
is the same, but in the outer rainbow they are fainter and their position
is reversed. In the inner rainbow the first and largest band is red;
in the outer rainbow the band that is nearest to this one and smallest
is of the same colour: the other bands correspond on the same principle.
These are almost the only colours which painters cannot manufacture:
for there are colours which they create by mixing, but no mixing will
give red, green, or purple. These are the colours of the rainbow,
though between the red and the green an orange colour is often seen.

Mock suns and rods are always seen by the side of the sun, not above
or below it nor in the opposite quarter of the sky. They are not seen
at night but always in the neighbourhood of the sun, either as it
is rising or setting but more commonly towards sunset. They have scarcely
ever appeared when the sun was on the meridian, though this once happened
in Bosporus where two mock suns rose with the sun and followed it
all through the day till sunset.

These are the facts about each of these phenomena: the cause of them
all is the same, for they are all reflections. But they are different
varieties, and are distinguished by the surface from which and the
way in which the reflection to the sun or some other bright object
takes place.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:03:31 am
The rainbow is seen by day, and it was formerly thought that it never
appeared by night as a moon rainbow. This opinion was due to the rarity
of the occurrence: it was not observed, for though it does happen
it does so rarely. The reason is that the colours are not so easy
to see in the dark and that many other conditions must coincide, and
all that in a single day in the month. For if there is to be one it
must be at full moon, and then as the moon is either rising or setting.
So we have only met with two instances of a moon rainbow in more than
fifty years.

We must accept from the theory of optics the fact that sight is reflected
from air and any object with a smooth surface just as it is from water;
also that in some mirrors the forms of things are reflected, in others
only their colours. Of the latter kind are those mirrors which are
so small as to be indivisible for sense. It is impossible that the
figure of a thing should be reflected in them, for if it is the mirror
will be sensibly divisible since divisibility is involved in the notion
of figure. But since something must be reflected in them and figure
cannot be, it remains that colour alone should be reflected. The colour
of a bright object sometimes appears bright in the reflection, but
it sometimes, either owing to the admixture of the colour of the mirror
or to weakness of sight, gives rise to the appearance of another colour.

However, we must accept the account we have given of these things
in the theory of sensation, and take some things for granted while
we explain others.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:03:47 am
Part 3

Let us begin by explaining the shape of the halo; why it is a circle
and why it appears round the sun or the moon or one of the other stars:
the explanation being in all these cases the same.

Sight is reflected in this way when air and vapour are condensed into
a cloud and the condensed matter is uniform and consists of small
parts. Hence in itself it is a sign of rain, but if it fades away,
of fine weather, if it is broken up, of wind. For if it does not fade
away and is not broken up but is allowed to attain its normal state,
it is naturally a sign of rain since it shows that a process of condensation
is proceeding which must, when it is carried to an end, result in
rain. For the same reason these haloes are the darkest. It is a sign
of wind when it is broken up because its breaking up is due to a wind
which exists there but has not reached us. This view finds support
in the fact that the wind blows from the quarter in which the main
division appears in the halo. Its fading away is a sign of fine weather
because if the air is not yet in a state to get the better of the
heat it contains and proceed to condense into water, this shows that
the moist vapour has not yet separated from the dry and firelike exhalation:
and this is the cause of fine weather.

So much for the atmospheric conditions under which the reflection
takes place. The reflection is from the mist that forms round the
sun or the moon, and that is why the halo is not seen opposite the
sun like the rainbow.

Since the reflection takes place in the same way from every point
the result is necessarily a circle or a segment of a circle: for if
the lines start from the same point and end at the same point and
are equal, the points where they form an angle will always lie on
a circle.

Let AGB and AZB and ADB be lines each of which goes from the point
A to the point B and forms an angle. Let the lines AG, AZ, AD be equal
and those at B, GB, ZB, DB equal too. (See diagram.)

Draw the line AEB. Then the triangles are equal; for their base Aeb
is equal. Draw perpendiculars to AEB from the angles; GE from G, Ze
from Z, DE from D. Then these perpendiculars are equal, being in equal
triangles. And they are all in one plane, being all at right angles
to AEB and meeting at a single point E. So if you draw the line it
will be a circle and E its centre. Now B is the sun, A the eye, and
the circumference passing through the points GZD the cloud from which
the line of sight is reflected to the sun.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:04:03 am
The mirrors must be thought of as contiguous: each of them is too
small to be visible, but their contiguity makes the whole made up
of them all to seem one. The bright band is the sun, which is seen
as a circle, appearing successively in each of the mirrors as a point
indivisible to sense. The band of cloud next to it is black, its colour
being intensified by contrast with the brightness of the halo. The
halo is formed rather near the earth because that is calmer: for where
there is wind it is clear that no halo can maintain its position.

Haloes are commoner round the moon because the greater heat of the
sun dissolves the condensations of the air more rapidly.

Haloes are formed round stars for the same reasons, but they are not
prognostic in the same way because the condensation they imply is
so insignificant as to be barren.

Part 4

We have already stated that the rainbow is a reflection: we have now
to explain what sort of reflection it is, to describe its various
concomitants, and to assign their causes.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:04:24 am
Sight is reflected from all smooth surfaces, such as are air and water
among others. Air must be condensed if it is to act as a mirror, though
it often gives a reflection even uncondensed when the sight is weak.
Such was the case of a man whose sight was faint and indistinct. He
always saw an image in front of him and facing him as he walked. This
was because his sight was reflected back to him. Its morbid condition
made it so weak and delicate that the air close by acted as a mirror,
just as distant and condensed air normally does, and his sight could
not push it back. So promontories in the sea 'loom' when there is
a south-east wind, and everything seems bigger, and in a mist, too,
things seem bigger: so, too, the sun and the stars seem bigger when
rising and setting than on the meridian. But things are best reflected
from water, and even in process of formation it is a better mirror
than air, for each of the particles, the union of which constitutes
a raindrop, is necessarily a better mirror than mist. Now it is obvious
and has already been stated that a mirror of this kind renders the
colour of an object only, but not its shape. Hence it follows that
when it is on the point of raining and the air in the clouds is in
process of forming into raindrops but the rain is not yet actually
there, if the sun is opposite, or any other object bright enough to
make the cloud a mirror and cause the sight to be reflected to the
object then the reflection must render the colour of the object without
its shape. Since each of the mirrors is so small as to be invisible
and what we see is the continuous magnitude made up of them all, the
reflection necessarily gives us a continuous magnitude made up of
one colour; each of the mirrors contributing the same colour to the
whole. We may deduce that since these conditions are realizable there
will be an appearance due to reflection whenever the sun and the cloud
are related in the way described and we are between them. But these
are just the conditions under which the rainbow appears. So it is
clear that the rainbow is a reflection of sight to the sun.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:04:43 am
So the rainbow always appears opposite the sun whereas the halo is
round it. They are both reflections, but the rainbow is distinguished
by the variety of its colours. The reflection in the one case is from
water which is dark and from a distance; in the other from air which
is nearer and lighter in colour. White light through a dark medium
or on a dark surface (it makes no difference) looks red. We know how
red the flame of green wood is: this is because so much smoke is mixed
with the bright white firelight: so, too, the sun appears red through
smoke and mist. That is why in the rainbow reflection the outer circumference
is red (the reflection being from small particles of water), but not
in the case of the halo. The other colours shall be explained later.
Again, a condensation of this kind cannot persist in the neighbourhood
of the sun: it must either turn to rain or be dissolved, but opposite
to the sun there is an interval during which the water is formed.
If there were not this distinction haloes would be coloured like the
rainbow. Actually no complete or circular halo presents this colour,
only small and fragmentary appearances called 'rods'. But if a haze
due to water or any other dark substance formed there we should have
had, as we maintain, a complete rainbow like that which we do find
lamps. A rainbow appears round these in winter, generally with southerly
winds. Persons whose eyes are moist see it most clearly because their
sight is weak and easily reflected. It is due to the moistness of
the air and the soot which the flame gives off and which mixes with
the air and makes it a mirror, and to the blackness which that mirror
derives from the smoky nature of the soot. The light of the lamp appears
as a circle which is not white but purple. It shows the colours of
the rainbow; but because the sight that is reflected is too weak and
the mirror too dark, red is absent. The rainbow that is seen when
oars are raised out of the sea involves the same relative positions
as that in the sky, but its colour is more like that round the lamps,
being purple rather than red. The reflection is from very small particles
continuous with one another, and in this case the particles are fully
formed water. We get a rainbow, too, if a man sprinkles fine drops
in a room turned to the sun so that the sun is shining in part of
the room and throwing a shadow in the rest. Then if one man sprinkles
in the room, another, standing outside, sees a rainbow where the sun's
rays cease and make the shadow. Its nature and colour is like that
from the oars and its cause is the same, for the sprinkling hand corresponds
to the oar.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:04:53 am
That the colours of the rainbow are those we described and how the
other colours come to appear in it will be clear from the following
considerations. We must recognize, as we have said, and lay down:
first, that white colour on a black surface or seen through a black
medium gives red; second, that sight when strained to a distance becomes
weaker and less; third, that black is in a sort the negation of sight:
an object is black because sight fails; so everything at a distance
looks blacker, because sight does not reach it. The theory of these
matters belongs to the account of the senses, which are the proper
subjects of such an inquiry; we need only state about them what is
necessary for us. At all events, that is the reason why distant objects
and objects seen in a mirror look darker and smaller and smoother,
why the reflection of clouds in water is darker than the clouds themselves.
This latter is clearly the case: the reflection diminishes the sight
that reaches them. It makes no difference whether the change is in
the object seen or. in the sight, the result being in either case
the same. The following fact further is worth noticing. When there
is a cloud near the sun and we look at it does not look coloured at
all but white, but when we look at the same cloud in water it shows
a trace of rainbow colouring. Clearly, then, when sight is reflected
it is weakened and, as it makes dark look darker, so it makes white
look less white, changing it and bringing it nearer to black. When
the sight is relatively strong the change is to red; the next stage
is green, and a further degree of weakness gives violet. No further
change is visible, but three completes the series of colours (as we
find three does in most other things), and the change into the rest
is imperceptible to sense. Hence also the rainbow appears with three
colours; this is true of each of the two, but in a contrary way. The
outer band of the primary rainbow is red: for the largest band reflects
most sight to the sun, and the outer band is largest. The middle band
and the third go on the same principle. So if the principles we laid
down about the appearance of colours are true the rainbow necessarily
has three colours, and these three and no others. The appearance of
yellow is due to contrast, for the red is whitened by its juxtaposition
with green. We can see this from the fact that the rainbow is purest
when the cloud is blackest; and then the red shows most yellow. (Yellow
in the rainbow comes between red and green.) So the whole of the red
shows white by contrast with the blackness of the cloud around: for
it is white compared to the cloud and the green. Again, when the rainbow
is fading away and the red is dissolving, the white cloud is brought
into contact with the green and becomes yellow. But the moon rainbow
affords the best instance of this colour contrast. It looks quite
white: this is because it appears on the dark cloud and at night.
So, just as fire is intensified by added fire, black beside black
makes that which is in some degree white look quite white. Bright
dyes too show the effect of contrast. In woven and embroidered stuffs
the appearance of colours is profoundly affected by their juxtaposition
with one another (purple, for instance, appears different on white
and on black wool), and also by differences of illumination. Thus
embroiderers say that they often make mistakes in their colours when
they work by lamplight, and use the wrong ones.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:05:12 am
We have now shown why the rainbow has three colours and that these
are its only colours. The same cause explains the double rainbow and
the faintness of the colours in the outer one and their inverted order.
When sight is strained to a great distance the appearance of the distant
object is affected in a certain way: and the same thing holds good
here. So the reflection from the outer rainbow is weaker because it
takes place from a greater distance and less of it reaches the sun,
and so the colours seen are fainter. Their order is reversed because
more reflection reaches the sun from the smaller, inner band. For
that reflection is nearer to our sight which is reflected from the
band which is nearest to the primary rainbow. Now the smallest band
in the outer rainbow is that which is nearest, and so it will be red;
and the second and the third will follow the same principle. Let B
be the outer rainbow, A the inner one; let R stand for the red colour,
G for green, V for violet; yellow appears at the point Y. Three rainbows
or more are not found because even the second is fainter, so that
the third reflection can have no strength whatever and cannot reach
the sun at all. (See diagram.)

Part 5

The rainbow can never be a circle nor a segment of a circle greater
than a semicircle. The consideration of the diagram will prove this
and the other properties of the rainbow. (See diagram.)


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:05:24 am
Let A be a hemisphere resting on the circle of the horizon, let its
centre be K and let H be another point appearing on the horizon. Then,
if the lines that fall in a cone from K have HK as their axis, and,
K and M being joined, the lines KM are reflected from the hemisphere
to H over the greater angle, the lines from K will fall on the circumference
of a circle. If the reflection takes place when the luminous body
is rising or setting the segment of the circle above the earth which
is cut off by the horizon will be a semi-circle; if the luminous body
is above the horizon it will always be less than a semicircle, and
it will be smallest when the luminous body culminates. First let the
luminous body be appearing on the horizon at the point H, and let
KM be reflected to H, and let the plane in which A is, determined
by the triangle HKM, be produced. Then the section of the sphere will
be a great circle. Let it be A (for it makes no difference which of
the planes passing through the line HK and determined by the triangle
KMH is produced). Now the lines drawn from H and K to a point on the
semicircle A are in a certain ratio to one another, and no lines drawn
from the same points to another point on that semicircle can have
the same ratio. For since both the points H and K and the line KH
are given, the line MH will be given too; consequently the ratio of
the line MH to the line MK will be given too. So M will touch a given
circumference. Let this be NM. Then the intersection of the circumferences
is given, and the same ratio cannot hold between lines in the same
plane drawn from the same points to any other circumference but MN.

Draw a line DB outside of the figure and divide it so that D:B=MH:MK.
But MH is greater than MK since the reflection of the cone is over
the greater angle (for it subtends the greater angle of the triangle
KMH). Therefore D is greater than B. Then add to B a line Z such that
B+Z:D=D:B. Then make another line having the same ratio to B as KH
has to Z, and join MI.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:05:47 am
Then I is the pole of the circle on which the lines from K fall. For
the ratio of D to IM is the same as that of Z to KH and of B to KI.
If not, let D be in the same ratio to a line indifferently lesser
or greater than IM, and let this line be IP. Then HK and KI and IP
will have the same ratios to one another as Z, B, and D. But the ratios
between Z, B, and D were such that Z+B:D=D: B. Therefore Ih:IP=IP:IK.
Now, if the points K, H be joined with the point P by the lines HP,
KP, these lines will be to one another as IH is to IP, for the sides
of the triangles HIP, KPI about the angle I are homologous. Therefore,
HP too will be to KP as HI is to IP. But this is also the ratio of
MH to MK, for the ratio both of HI to IP and of Mh to MK is the same
as that of D to B. Therefore, from the points H, K there will have
been drawn lines with the same ratio to one another, not only to the
circumference MN but to another point as well, which is impossible.
Since then D cannot bear that ratio to any line either lesser or greater
than IM (the proof being in either case the same), it follows that
it must stand in that ratio to MI itself. Therefore as MI is to IK
so IH will be to MI and finally MH to Mk.

If, then, a circle be described with I as pole at the distance MI
it will touch all the angles which the lines from H and K make by
their reflection. If not, it can be shown, as before, that lines drawn
to different points in the semicircle will have the same ratio to
one another, which was impossible. If, then, the semicircle A be revolved
about the diameter HKI, the lines reflected from the points H, K at
the point M will have the same ratio, and will make the angle KMH
equal, in every plane. Further, the angle which HM and MI make with
HI will always be the same. So there are a number of triangles on
HI and KI equal to the triangles HMI and KMI. Their perpendiculars
will fall on HI at the same point and will be equal. Let O be the
point on which they fall. Then O is the centre of the circle, half
of which, MN, is cut off by the horizon. (See diagram.)


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:06:05 am
Next let the horizon be ABG but let H have risen above the horizon.
Let the axis now be HI. The proof will be the same for the rest as
before, but the pole I of the circle will be below the horizon Ag
since the point H has risen above the horizon. But the pole, and the
centre of the circle, and the centre of that circle (namely HI) which
now determines the position of the sun are on the same line. But since
KH lies above the diameter AG, the centre will be at O on the line
KI below the plane of the circle AG determined the position of the
sun before. So the segment YX which is above the horizon will be less
than a semicircle. For YXM was a semicircle and it has now been cut
off by the horizon AG. So part of it, YM, will be invisible when the
sun has risen above the horizon, and the segment visible will be smallest
when the sun is on the meridian; for the higher H is the lower the
pole and the centre of the circle will be.

In the shorter days after the autumn equinox there may be a rainbow
at any time of the day, but in the longer days from the spring to
the autumn equinox there cannot be a rainbow about midday. The reason
for this is that when the sun is north of the equator the visible
arcs of its course are all greater than a semicircle, and go on increasing,
while the invisible arc is small, but when the sun is south of the
equator the visible arc is small and the invisible arc great, and
the farther the sun moves south of the equator the greater is the
invisible arc. Consequently, in the days near the summer solstice,
the size of the visible arc is such that before the point H reaches
the middle of that arc, that is its point of culmination, the point
is well below the horizon; the reason for this being the great size
of the visible arc, and the consequent distance of the point of culmination
from the earth. But in the days near the winter solstice the visible
arcs are small, and the contrary is necessarily the case: for the
sun is on the meridian before the point H has risen far.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:06:20 am
Part 6

Mock suns, and rods too, are due to the causes we have described.
A mock sun is caused by the reflection of sight to the sun. Rods are
seen when sight reaches the sun under circumstances like those which
we described, when there are clouds near the sun and sight is reflected
from some liquid surface to the cloud. Here the clouds themselves
are colourless when you look at them directly, but in the water they
are full of rods. The only difference is that in this latter case
the colour of the cloud seems to reside in the water, but in the case
of rods on the cloud itself. Rods appear when the composition of the
cloud is uneven, dense in part and in part rare, and more and less
watery in different parts. Then the sight is reflected to the sun:
the mirrors are too small for the shape of the sun to appear, but,
the bright white light of the sun, to which the sight is reflected,
being seen on the uneven mirror, its colour appears partly red, partly
green or yellow. It makes no difference whether sight passes through
or is reflected from a medium of that kind; the colour is the same
in both cases; if it is red in the first case it must be the same
in the other.

Rods then are occasioned by the unevenness of the mirror-as regards
colour, not form. The mock sun, on the contrary, appears when the
air is very uniform, and of the same density throughout. This is why
it is white: the uniform character of the mirror gives the reflection
in it a single colour, while the fact that the sight is reflected
in a body and is thrown on the sun all together by the mist, which
is dense and watery though not yet quite water, causes the sun's true
colour to appear just as it does when the reflection is from the dense,
smooth surface of copper. So the sun's colour being white, the mock
sun is white too. This, too, is the reason why the mock sun is a surer
sign of rain than the rods; it indicates, more than they do, that
the air is ripe for the production of water. Further a mock sun to
the south is a surer sign of rain than one to the north, for the air
in the south is readier to turn into water than that in the north.

Mock suns and rods are found, as we stated, about sunset and sunrise,
not above the sun nor below it, but beside it. They are not found
very close to the sun, nor very far from it, for the sun dissolves
the cloud if it is near, but if it is far off the reflection cannot
take place, since sight weakens when it is reflected from a small
mirror to a very distant object. (This is why a halo is never found
opposite to the sun.) If the cloud is above the sun and close to it
the sun will dissolve it; if it is above the sun but at a distance
the sight is too weak for the reflection to take place, and so it
will not reach the sun. But at the side of the sun, it is possible
for the mirror to be at such an interval that the sun does not dissolve
the cloud, and yet sight reaches it undiminished because it moves
close to the earth and is not dissipated in the immensity of space.
It cannot subsist below the sun because close to the earth the sun's
rays would dissolve it, but if it were high up and the sun in the
middle of the heavens, sight would be dissipated. Indeed, even by
the side of the sun, it is not found when the sun is in the middle
of the sky, for then the line of vision is not close to the earth,
and so but little sight reaches the mirror and the reflection from
it is altogether feeble.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:06:38 am
Some account has now been given of the effects of the secretion above
the surface of the earth; we must go on to describe its operations
below, when it is shut up in the parts of the earth.

Just as its twofold nature gives rise to various effects in the upper
region, so here it causes two varieties of bodies. We maintain that
there are two exhalations, one vaporous the other smoky, and there
correspond two kinds of bodies that originate in the earth, 'fossiles'
and metals. The heat of the dry exhalation is the cause of all 'fossiles'.
Such are the kinds of stones that cannot be melted, and realgar, and
ochre, and ruddle, and sulphur, and the other things of that kind,
most 'fossiles' being either coloured lye or, like cinnabar, a stone
compounded of it. The vaporous exhalation is the cause of all metals,
those bodies which are either fusible or malleable such as iron, copper,
gold. All these originate from the imprisonment of the vaporous exhalation
in the earth, and especially in stones. Their dryness compresses it,
and it congeals just as dew or hoar-frost does when it has been separated
off, though in the present case the metals are generated before that
segregation occurs. Hence, they are water in a sense, and in a sense
not. Their matter was that which might have become water, but it can
no longer do so: nor are they, like savours, due to a qualitative
change in actual water. Copper and gold are not formed like that,
but in every case the evaporation congealed before water was formed.
Hence, they all (except gold) are affected by fire, and they possess
an admixture of earth; for they still contain the dry exhalation.

This is the general theory of all these bodies, but we must take up
each kind of them and discuss it separately.

----------------------------------------------------------------------


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:06:48 am
BOOK IV

Part 1

We have explained that the qualities that constitute the elements
are four, and that their combinations determine the number of the
elements to be four.

Two of the qualities, the hot and the cold, are active; two, the dry
and the moist, passive. We can satisfy ourselves of this by looking
at instances. In every case heat and cold determine, conjoin, and
change things of the same kind and things of different kinds, moistening,
drying, hardening, and softening them. Things dry and moist, on the
other hand, both in isolation and when present together in the same
body are the subjects of that determination and of the other affections
enumerated. The account we give of the qualities when we define their
character shows this too. Hot and cold we describe as active, for
'congregating' is essentially a species of 'being active': moist and
dry are passive, for it is in virtue of its being acted upon in a
certain way that a thing is said to be 'easy to determine' or 'difficult
to determine'. So it is clear that some of the qualities are active
and some passive.

Next we must describe the operations of the active qualities and the
forms taken by the passive. First of all, true becoming, that is,
natural change, is always the work of these powers and so is the corresponding
natural destruction; and this becoming and this destruction are found
in plants and animals and their parts. True natural becoming is a
change introduced by these powers into the matter underlying a given
thing when they are in a certain ratio to that matter, which is the
passive qualities we have mentioned. When the hot and the cold are
masters of the matter they generate a thing: if they are not, and
the failure is partial, the object is imperfectly boiled or otherwise
unconcocted. But the strictest general opposite of true becoming is
putrefaction. All natural destruction is on the way to it, as are,
for instance, growing old or growing dry. Putrescence is the end of
all these things, that is of all natural objects, except such as are
destroyed by violence: you can burn, for instance, flesh, bone, or
anything else, but the natural course of their destruction ends in
putrefaction. Hence things that putrefy begin by being moist and end
by being dry. For the moist and the dry were their matter, and the
operation of the active qualities caused the dry to be determined
by the moist.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:07:03 am
Destruction supervenes when the determined gets the better of the
determining by the help of the environment (though in a special sense
the word putrefaction is applied to partial destruction, when a thing's
nature is perverted). Hence everything, except fire, is liable to
putrefy; for earth, water, and air putrefy, being all of them matter
relatively to fire. The definition of putrefaction is: the destruction
of the peculiar and natural heat in any moist subject by external
heat, that is, by the heat of the environment. So since lack of heat
is the ground of this affection and everything in as far as it lacks
heat is cold, both heat and cold will be the causes of putrefaction,
which will be due indifferently to cold in the putrefying subject
or to heat in the environment.

This explains why everything that putrefies grows drier and ends by
becoming earth or dung. The subject's own heat departs and causes
the natural moisture to evaporate with it, and then there is nothing
left to draw in moisture, for it is a thing's peculiar heat that attracts
moisture and draws it in. Again, putrefaction takes place less in
cold that in hot seasons, for in winter the surrounding air and water
contain but little heat and it has no power, but in summer there is
more. Again, what is frozen does not putrefy, for its cold is greater
that the heat of the air and so is not mastered, whereas what affects
a thing does master it. Nor does that which is boiling or hot putrefy,
for the heat in the air being less than that in the object does not
prevail over it or set up any change. So too anything that is flowing
or in motion is less apt to putrefy than a thing at rest, for the
motion set up by the heat in the air is weaker than that pre-existing
in the object, and so it causes no change. For the same reason a great
quantity of a thing putrefies less readily than a little, for the
greater quantity contains too much proper fire and cold for the corresponding
qualities in the environment to get the better of. Hence, the sea
putrefies quickly when broken up into parts, but not as a whole; and
all other waters likewise. Animals too are generated in putrefying
bodies, because the heat that has been secreted, being natural, organizes
the particles secreted with it.

So much for the nature of becoming and of destruction.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:07:19 am
Part 2

We must now describe the next kinds of processes which the qualities
already mentioned set up in actually existing natural objects as matter.

Of these concoction is due to heat; its species are ripening, boiling,
broiling. Inconcoction is due to cold and its species are rawness,
imperfect boiling, imperfect broiling. (We must recognize that the
things are not properly denoted by these words: the various classes
of similar objects have no names universally applicable to them; consequently
we must think of the species enumerated as being not what those words
denote but something like it.) Let us say what each of them is. Concoction
is a process in which the natural and proper heat of an object perfects
the corresponding passive qualities, which are the proper matter of
any given object. For when concoction has taken place we say that
a thing has been perfected and has come to be itself. It is the proper
heat of a thing that sets up this perfecting, though external influences
may contribute in some degrees to its fulfilment. Baths, for instance,
and other things of the kind contribute to the digestion of food,
but the primary cause is the proper heat of the body. In some cases
of concoction the end of the process is the nature of the thing-nature,
that is, in the sense of the formal cause and essence. In other cases
it leads to some presupposed state which is attained when the moisture
has acquired certain properties or a certain magnitude in the process
of being broiled or boiled or of putrefying, or however else it is
being heated. This state is the end, for when it has been reached
the thing has some use and we say that concoction has taken place.
Must is an instance of this, and the matter in boils when it becomes
purulent, and tears when they become rheum, and so with the rest.

Concoction ensues whenever the matter, the moisture, is mastered.
For the matter is what is determined by the heat connatural to the
object, and as long as the ratio between them exists in it a thing
maintains its nature. Hence things like the liquid and solid excreta
and ejecta in general are signs of health, and concoction is said
to have taken place in them, for they show that the proper heat has
got the better of the indeterminate matter.

Things that undergo a process of concoction necessarily become thicker
and hotter, for the action of heat is to make things more compact,
thicker, and drier.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:07:35 am
This then is the nature of concoction: but inconcoction is an imperfect
state due to lack of proper heat, that is, to cold. That of which
the imperfect state is, is the corresponding passive qualities which
are the natural matter of anything.

So much for the definition of concoction and inconcoction.

Part 3

Ripening is a sort of concoction; for we call it ripening when there
is a concoction of the nutriment in fruit. And since concoction is
a sort of perfecting, the process of ripening is perfect when the
seeds in fruit are able to reproduce the fruit in which they are found;
for in all other cases as well this is what we mean by 'perfect'.
This is what 'ripening' means when the word is applied to fruit. However,
many other things that have undergone concoction are said to be 'ripe',
the general character of the process being the same, though the word
is applied by an extension of meaning. The reason for this extension
is, as we explained before, that the various modes in which natural
heat and cold perfect the matter they determine have not special names
appropriated to them. In the case of boils and phlegm, and the like,
the process of ripening is the concoction of the moisture in them
by their natural heat, for only that which gets the better of matter
can determine it. So everything that ripens is condensed from a spirituous
into a watery state, and from a watery into an earthy state, and in
general from being rare becomes dense. In this process the nature
of the thing that is ripening incorporates some of the matter in itself,
and some it rejects. So much for the definition of ripening.

Rawness is its opposite and is therefore an imperfect concoction of
the nutriment in the fruit, namely, of the undetermined moisture.
Consequently a raw thing is either spirituous or watery or contains
both spirit and water. Ripening being a kind of perfecting, rawness
will be an imperfect state, and this state is due to a lack of natural
heat and its disproportion to the moisture that is undergoing the
process of ripening. (Nothing moist ripens without the admixture of
some dry matter: water alone of liquids does not thicken.) This disproportion
may be due either to defect of heat or to excess of the matter to
be determined: hence the juice of raw things is thin, cold rather
than hot, and unfit for food or drink. Rawness, like ripening, is
used to denote a variety of states. Thus the liquid and solid excreta
and catarrhs are called raw for the same reason, for in every case
the word is applied to things because their heat has not got the mastery
in them and compacted them. If we go further, brick is called raw
and so is milk and many other things too when they are such as to
admit of being changed and compacted by heat but have remained unaffected.
Hence, while we speak of 'boiled' water, we cannot speak of raw water,
since it does not thicken. We have now defined ripening and rawness
and assigned their causes.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:07:53 am
Boiling is, in general, a concoction by moist heat of the indeterminate
matter contained in the moisture of the thing boiled, and the word
is strictly applicable only to things boiled in the way of cooking.
The indeterminate matter, as we said, will be either spirituous or
watery. The cause of the concoction is the fire contained in the moisture;
for what is cooked in a frying-pan is broiled: it is the heat outside
that affects it and, as for the moisture in which it is contained,
it dries this up and draws it into itself. But a thing that is being
boiled behaves in the opposite way: the moisture contained in it is
drawn out of it by the heat in the liquid outside. Hence boiled meats
are drier than broiled; for, in boiling, things do not draw the moisture
into themselves, since the external heat gets the better of the internal:
if the internal heat had got the better it would have drawn the moisture
to itself. Not every body admits of the process of boiling: if there
is no moisture in it, it does not (for instance, stones), nor does
it if there is moisture in it but the density of the body is too great
for it-to-be mastered, as in the case of wood. But only those bodies
can be boiled that contain moisture which can be acted on by the heat
contained in the liquid outside. It is true that gold and wood and
many other things are said to be 'boiled': but this is a stretch of
the meaning of the word, though the kind of thing intended is the
same, the reason for the usage being that the various cases have no
names appropriated to them. Liquids too, like milk and must, are said
to undergo a process of 'boiling' when the external fire that surrounds
and heats them changes the savour in the liquid into a given form,
the process being thus in a way like what we have called boiling.

The end of the things that undergo boiling, or indeed any form of
concoction, is not always the same: some are meant to be eaten, some
drunk, and some are intended for other uses; for instance dyes, too,
are said to be 'boiled'.

All those things then admit of 'boiling' which can grow denser, smaller,
or heavier; also those which do that with a part of themselves and
with a part do the opposite, dividing in such a way that one portion
thickens while the other grows thinner, like milk when it divides
into whey and curd. Oil by itself is affected in none of these ways,
and therefore cannot be said to admit of 'boiling'. Such then is the
pfcies of concoction known as 'boiling', and the process is the same
in an artificial and in a natural instrument, for the cause will be
the same in every case.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:08:08 am
Imperfect boiling is the form of inconcoction opposed to boiling.
Now the opposite of boiling properly so called is an inconcoction
of the undetermined matter in a body due to lack of heat in the surrounding
liquid. (Lack of heat implies, as we have pointed out, the presence
of cold.) The motion which causes imperfect boiling is different from
that which causes boiling, for the heat which operates the concoction
is driven out. The lack of heat is due either to the amount of cold
in the liquid or to the quantity of moisture in the object undergoing
the process of boiling. Where either of these conditions is realized
the heat in the surrounding liquid is too great to have no effect
at all, but too small to carry out the process of concocting uniformly
and thoroughly. Hence things are harder when they are imperfectly
boiled than when they are boiled, and the moisture in them more distinct
from the solid parts. So much for the definition and causes of boiling
and imperfect boiling.

Broiling is concoction by dry foreign heat. Hence if a man were to
boil a thing but the change and concoction in it were due, not to
the heat of the liquid but to that of the fire, the thing will have
been broiled and not boiled when the process has been carried to completion:
if the process has gone too far we use the word 'scorched' to describe
it. If the process leaves the thing drier at the end the agent has
been dry heat. Hence the outside is drier than the inside, the opposite
being true of things boiled. Where the process is artificial, broiling
is more difficult than boiling, for it is difficult to heat the inside
and the outside uniformly, since the parts nearer to the fire are
the first to get dry and consequently get more intensely dry. In this
way the outer pores contract and the moisture in the thing cannot
be secreted but is shut in by the closing of the pores. Now broiling
and boiling are artificial processes, but the same general kind of
thing, as we said, is found in nature too. The affections produced
are similar though they lack a name; for art imitates nature. For
instance, the concoction of food in the body is like boiling, for
it takes place in a hot and moist medium and the agent is the heat
of the body. So, too, certain forms of indigestion are like imperfect
boiling. And it is not true that animals are generated in the concoction
of food, as some say. Really they are generated in the excretion which
putrefies in the lower belly, and they ascend afterwards. For concoction
goes on in the upper belly but the excretion putrefies in the lower:
the reason for this has been explained elsewhere.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:08:23 am
We have seen that the opposite of boiling is imperfect boiling: now
there is something correspondingly opposed to the species of concoction
called broiling, but it is more difficult to find a name for it. It
would be the kind of thing that would happen if there were imperfect
broiling instead of broiling proper through lack of heat due to deficiency
in the external fire or to the quantity of water in the thing undergoing
the process. For then we should get too much heat for no effect to
be produced, but too little for concoction to take place.

We have now explained concoction and inconcoction, ripening and rawness,
boiling and broiling, and their opposites.

Part 4

We must now describe the forms taken by the passive qualities the
moist and the dry. The elements of bodies, that is, the passive ones,
are the moist and the dry; the bodies themselves are compounded of
them and whichever predominates determines the nature of the body;
thus some bodies partake more of the dry, others of the moist. All
the forms to be described will exist either actually, or potentially
and in their opposite: for instance, there is actual melting and on
the other hand that which admits of being melted.

Since the moist is easily determined and the dry determined with difficulty,
their relation to one another is like that of a dish and its condiments.
The moist is what makes the dry determinable, and each serves as a
sort of glue to the other-as Empedocles said in his poem on Nature,
'glueing meal together by means of water.' Thus the determined body
involves them both. Of the elements earth is especially representative
of the dry, water of the moist, and therefore all determinate bodies
in our world involve earth and water. Every body shows the quality
of that element which predominates in it. It is because earth and
water are the material elements of all bodies that animals live in
them alone and not in air or fire.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:08:38 am
Of the qualities of bodies hardness and softness are those which must
primarily belong to a determined thing, for anything made up of the
dry and the moist is necessarily either hard or soft. Hard is that
the surface of which does not yield into itself; soft that which does
yield but not by interchange of place: water, for instance, is not
soft, for its surface does not yield to pressure or sink in but there
is an interchange of place. Those things are absolutely hard and soft
which satisfy the definition absolutely, and those things relatively
so which do so compared with another thing. Now relatively to one
another hard and soft are indefinable, because it is a matter of degree,
but since all the objects of sense are determined by reference to
the faculty of sense it is clearly the relation to touch which determines
that which is hard and soft absolutely, and touch is that which we
use as a standard or mean. So we call that which exceeds it hard and
that which falls short of it soft.

Part 5

A body determined by its own boundary must be either hard or soft;
for it either yields or does not.

It must also be concrete: or it could not be so determined. So since
everything that is determined and solid is either hard or soft and
these qualities are due to concretion, all composite and determined
bodies must involve concretion. Concretion therefore must be discussed.

Now there are two causes besides matter, the agent and the quality
brought about, the agent being the efficient cause, the quality the
formal cause. Hence concretion and disaggregation, drying and moistening,
must have these two causes.

But since concretion is a form of drying let us speak of the latter
first.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:09:25 am
As we have explained, the agent operates by means of two qualities
and the patient is acted on in virtue of two qualities: action takes
place by means of heat or cold, and the quality is produced either
by the presence or by the absence of heat or cold; but that which
is acted upon is moist or dry or a compound of both. Water is the
element characterized by the moist, earth that characterized by the
dry, for these among the elements that admit the qualities moist and
dry are passive. Therefore cold, too, being found in water and earth
(both of which we recognize to be cold), must be reckoned rather as
a passive quality. It is active only as contributing to destruction
or incidentally in the manner described before; for cold is sometimes
actually said to burn and to warm, but not in the same way as heat
does, but by collecting and concentrating heat.

The subjects of drying are water and the various watery fluids and
those bodies which contain water either foreign or connatural. By
foreign I mean like the water in wool, by connatural, like that in
milk. The watery fluids are wine, urine, whey, and in general those
fluids which have no sediment or only a little, except where this
absence of sediment is due to viscosity. For in some cases, in oil
and pitch for instance, it is the viscosity which prevents any sediment
from appearing.

It is always a process of heating or cooling that dries things, but
the agent in both cases is heat, either internal or external. For
even when things are dried by cooling, like a garment, where the moisture
exists separately it is the internal heat that dries them. It carries
off the moisture in the shape of vapour (if there is not too much
of it), being itself driven out by the surrounding cold. So everything
is dried, as we have said, by a process either of heating or cooling,
but the agent is always heat, either internal or external, carrying
off the moisture in vapour. By external heat I mean as where things
are boiled: by internal where the heat breathes out and takes away
and uses up its moisture. So much for drying.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:09:46 am
Part 6

Liquefaction is, first, condensation into water; second, the melting
of a solidified body. The first, condensation, is due to the cooling
of vapour: what melting is will appear from the account of solidification.

Whatever solidifies is either water or a mixture of earth and water,
and the agent is either dry heat or cold. Hence those of the bodies
solidified by heat or cold which are soluble at all are dissolved
by their opposites. Bodies solidified by the dry-hot are dissolved
by water, which is the moist-cold, while bodies solidified by cold
are dissolved by fire, which is hot. Some things seem to be solidified
by water, e.g. boiled honey, but really it is not the water but the
cold in the water which effects the solidification. Aqueous bodies
are not solidified by fire: for it is fire that dissolves them, and
the same cause in the same relation cannot have opposite effects upon
the same thing. Again, water solidifies owing to the departure of
heat; so it will clearly be dissolved by the entry into it of heat:
cold, therefore, must be the agent in solidifying it.

Hence aqueous bodies do not thicken when they solidify; for thickening
occurs when the moisture goes off and the dry matter comes together,
but water is the only liquid that does not thicken. Those bodies that
are made up of both earth and water are solidified both by fire and
by cold and in either case are thickened. The operation of the two
is in a way the same and in a way different. Heat acts by drawing
off the moisture, and as the moisture goes off in vapour the dry matter
thickens and collects. Cold acts by driving out the heat, which is
accompanied by the moisture as this goes off in vapour with it. Bodies
that are soft but not liquid do not thicken but solidify when the
moisture leaves them, e.g. potter's clay in process of baking: but
those mixed bodies that are liquid thicken besides solidifying, like
milk. Those bodies which have first been thickened or hardened by
cold often begin by becoming moist: thus potter's clay at first in
the process of baking steams and grows softer, and is liable to distortion
in the ovens for that reason.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:09:59 am
Now of the bodies solidified by cold which are made up both of earth
and water but in which the earth preponderates, those which solidify
by the departure of heat melt by heat when it enters into them again;
this is the case with frozen mud. But those which solidify by refrigeration,
where all the moisture has gone off in vapour with the heat, like
iron and horn, cannot be dissolved except by excessive heat, but they
can be softened-though manufactured iron does melt, to the point of
becoming fluid and then solidifying again. This is how steel is made.
The dross sinks to the bottom and is purged away: when this has been
done often and the metal is pure we have steel. The process is not
repeated often because the purification of the metal involves great
waste and loss of weight. But the iron that has less dross is the
better iron. The stone pyrimachus, too, melts and forms into drops
and becomes fluid; after having been in a fluid state it solidifies
and becomes hard again. Millstones, too, melt and become fluid: when
the fluid mass begins to solidify it is black but its consistency
comes to be like that of lime. and earth, too

Of the bodies which are solidified by dry heat some are insoluble,
others are dissolved by liquid. Pottery and some kinds of stone that
are formed out of earth burnt up by fire, such as millstones, cannot
be dissolved. Natron and salt are soluble by liquid, but not all liquid
but only such as is cold. Hence water and any of its varieties melt
them, but oil does not. For the opposite of the dry-hot is the cold-moist
and what the one solidified the other will dissolve, and so opposites
will have opposite effects.

Part 7

If a body contains more water than earth fire only thickens it: if
it contains more earth fire solidifies it. Hence natron and salt and
stone and potter's clay must contain more earth.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:10:13 am
The nature of oil presents the greatest problem. If water preponderated
in it, cold ought to solidify it; if earth preponderated, then fire
ought to do so. Actually neither solidifies, but both thicken it.
The reason is that it is full of air (hence it floats on the top of
water, since air tends to rise). Cold thickens it by turning the air
in it into water, for any mixture of oil and water is thicker than
either. Fire and the lapse of time thicken and whiten it. The whitening
follows on the evaporation of any water that may have been in it;
the is due to the change of the air into water as the heat in the
oil is dissipated. The effect in both cases is the same and the cause
is the same, but the manner of its operation is different. Both heat
and cold thicken it, but neither dries it (neither the sun nor cold
dries oil), not only because it is glutinous but because it contains
air. Its glutinous nature prevents it from giving off vapour and so
fire does not dry it or boil it off.

Those bodies which are made up of earth and water may be classified
according to the preponderance of either. There is a kind of wine,
for instance, which both solidifies and thickens by boiling-I mean,
must. All bodies of this kind lose their water as they That it is
their water may be seen from the fact that the vapour from them condenses
into water when collected. So wherever some sediment is left this
is of the nature of earth. Some of these bodies, as we have said,
are also thickened and dried by cold. For cold not only solidifies
but also dries water, and thickens things by turning air into water.
(Solidifying, as we have said, is a form of drying.) Now those things
that are not thickened by cold, but solidified, belong rather to water,
e.g.. wine, urine, vinegar, lye, whey. But those things that are thickened
(not by evaporation due to fire) are made up either of earth or of
water and air: honey of earth, while oil contains air. Milk and blood,
too, are made up of both water and earth, though earth generally predominates
in them. So, too, are the liquids out of which natron and salt are
formed; and stones are also formed from some mixtures of this kind.
Hence, if the whey has not been separated, it burns away if you boil
it over a fire. But the earthy element in milk can also be coagulated
by the help of fig-juice, if you boil it in a certain way as doctors
do when they treat it with fig-juice, and this is how the whey and
the cheese are commonly separated. Whey, once separated, does not
thicken, as the milk did, but boils away like water. Sometimes, however,
there is little or no cheese in milk, and such milk is not nutritive
and is more like water. The case of blood is similar: cold dries and
so solidifies it. Those kinds of blood that do not solidify, like
that of the stag, belong rather to water and are very cold. Hence
they contain no fibres: for the fibres are of earth and solid, and
blood from which they have been removed does not solidify. This is
because it cannot dry; for what remains is water, just as what remains
of milk when cheese has been removed is water. The fact that diseased
blood will not solidify is evidence of the same thing, for such blood
is of the nature of serum and that is phlegm and water, the nature
of the animal having failed to get the better of it and digest it.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:10:27 am
Some of these bodies are soluble, e.g. natron, some insoluble, e.g.
pottery: of the latter, some, like horn, can be softened by heat,
others, like pottery and stone, cannot. The reason is that opposite
causes have opposite effects: consequently, if solidification is due
to two causes, the cold and the dry, solution must be due to the hot
and the moist, that is, to fire and to water (these being opposites):
water dissolving what was solidified by fire alone, fire what was
solidified by cold alone. Consequently, if any things happen to be
solidified by the action of both, these are least apt to be soluble.
Such a case we find where things have been heated and are then solidified
by cold. When the heat in leaving them has caused most of the moisture
to evaporate, the cold so compacts these bodies together again as
to leave no entrance even for moisture. Therefore heat does not dissolve
them (for it only dissolves those bodies that are solidified by cold
alone), nor does water (for it does not dissolve what cold solidifies,
but only what is solidified by dry heat). But iron is melted by heat
and solidified by cold. Wood consists of earth and air and is therefore
combustible but cannot be melted or softened by heat. (For the same
reason it floats in water-all except ebony. This does not, for other
kinds of wood contain a preponderance of air, but in black ebony the
air has escaped and so earth preponderates in it.) Pottery consists
of earth alone because it solidified gradually in the process of drying.
Water cannot get into it, for the pores were only large enough to
admit of vapour escaping: and seeing that fire solidified it, that
cannot dissolve it either.

So solidification and melting, their causes, and the kinds of subjects
in which they occur have been described.

Part 8


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:10:46 am
All this makes it clear that bodies are formed by heat and cold and
that these agents operate by thickening and solidifying. It is because
these qualities fashion bodies that we find heat in all of them, and
in some cold in so far as heat is absent. These qualities, then, are
present as active, and the moist and the dry as passive, and consequently
all four are found in mixed bodies. So water and earth are the constituents
of homogeneous bodies both in plants and in animals and of metals
such as gold, silver, and the rest-water and earth and their respective
exhalations shut up in the compound bodies, as we have explained elsewhere.

All these mixed bodies are distinguished from one another, firstly
by the qualities special to the various senses, that is, by their
capacities of action. (For a thing is white, fragrant, sonant, sweet,
hot, cold in virtue of a power of acting on sense). Secondly by other
more characteristic affections which express their aptitude to be
affected: I mean, for instance, the aptitude to melt or solidify or
bend and so forth, all these qualities, like moist and dry, being
passive. These are the qualities that differentiate bone, flesh, sinew,
wood, bark, stone and all other homogeneous natural bodies. Let us
begin by enumerating these qualities expressing the aptitude or inaptitude
of a thing to be affected in a certain way. They are as follows: to
be apt or inapt to solidify, melt, be softened by heat, be softened
by water, bend, break, be comminuted, impressed, moulded, squeezed;
to be tractile or non-tractile, malleable or non-malleable, to be
fissile or non-fissile, apt or inapt to be cut; to be viscous or friable,
compressible or incompressible, combustible or incombustible; to be
apt or inapt to give off fumes. These affections differentiate most
bodies from one another. Let us go on to explain the nature of each
of them. We have already given a general account of that which is
apt or inapt to solidify or to melt, but let us return to them again
now. Of all the bodies that admit of solidification and hardening,
some are brought into this state by heat, others by cold. Heat does
this by drying up their moisture, cold by driving out their heat.
Consequently some bodies are affected in this way by defect of moisture,
some by defect of heat: watery bodies by defect of heat, earthy bodies
of moisture. Now those bodies that are so affected by defect of moisture
are dissolved by water, unless like pottery they have so contracted
that their pores are too small for the particles of water to enter.
All those bodies in which this is not the case are dissolved by water,
e.g. natron, salt, dry mud. Those bodies that solidified through defect
of heat are melted by heat, e.g. ice, lead, copper. So much for the
bodies that admit of solidification and of melting, and those that
do not admit of melting.

The bodies which do not admit of solidification are those which contain
no aqueous moisture and are not watery, but in which heat and earth
preponderate, like honey and must (for these are in a sort of state
of effervescence), and those which do possess some water but have
a preponderance of air, like oil and quicksilver, and all viscous
substances such as pitch and birdlime.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:11:09 am
Part 9

Those bodies admit of softening which are not (like ice) made up of
water, but in which earth predominates. All their moisture must not
have left them (as in the case of natron and salt), nor must the relation
of dry to moist in them be incongruous (as in the case of pottery).
They must be tractile (without admitting water) or malleable (without
consisting of water), and the agent in softening them is fire. Such
are iron and horn.

Both of bodies that can melt and of bodies that cannot, some do and
some do not admit of softening in water. Copper, for instance, which
can be melted, cannot be softened in water, whereas wool and earth
can be softened in water, for they can be soaked. (It is true that
though copper can be melted the agent in its case is not water, but
some of the bodies that can be melted by water too such as natron
and salt cannot be softened in water: for nothing is said to be so
affected unless the water soaks into it and makes it softer.) Some
things, on the other hand, such as wool and grain, can be softened
by water though they cannot be melted. Any body that is to be softened
by water must be of earth and must have its pores larger than the
particles of water, and the pores themselves must be able to resist
the action of water, whereas bodies that can be 'melted' by water
must have pores throughout.

(Why is it that earth is both 'melted' and softened by moisture, while
natron is 'melted' but not softened? Because natron is pervaded throughout
by pores so that the parts are immediately divided by the water, but
earth has also pores which do not connect and is therefore differently
affected according as the water enters by one or the other set of
pores.)


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:11:24 am
Some bodies can be bent or straightened, like the reed or the withy,
some cannot, like pottery and stone. Those bodies are apt to be bent
and straightened which can change from being curved to being straight
and from being straight to being curved, and bending and straightening
consist in the change or motion to the straight or to a curve, for
a thing is said to be in process of being bent whether it is being
made to assume a convex or a concave shape. So bending is defined
as motion to the convex or the concave without a change of length.
For if we added 'or to the straight', we should have a thing bent
and straight at once, and it is impossible for that which is straight
to be bent. And if all bending is a bending back or a bending down,
the former being a change to the convex, the latter to the concave,
a motion that leads to the straight cannot be called bending, but
bending and straightening are two different things. These, then, are
the things that can, and those that cannot be bent, and be straightened.

Some things can be both broken and comminuted, others admit only one
or the other. Wood, for instance, can be broken but not comminuted,
ice and stone can be comminuted but not broken, while pottery may
either be comminuted or broken. The distinction is this: breaking
is a division and separation into large parts, comminution into parts
of any size, but there must be more of them than two. Now those solids
that have many pores not communicating with one another are comminuible
(for the limit to their subdivision is set by the pores), but those
whose pores stretch continuously for a long way are breakable, while
those which have pores of both kinds are both comminuible and breakable.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:11:42 am
Some things, e.g. copper and wax, are impressible, others, e.g. pottery
and water, are not. The process of being impressed is the sinking
of a part of the surface of a thing in response to pressure or a blow,
in general to contact. Such bodies are either soft, like wax, where
part of the surface is depressed while the rest remains, or hard,
like copper. Non-impressible bodies are either hard, like pottery
(its surface does not give way and sink in), or liquid, like water
(for though water does give way it is not in a part of it, for there
is a reciprocal change of place of all its parts). Those impressibles
that retain the shape impressed on them and are easily moulded by
the hand are called 'plastic'; those that are not easily moulded,
such as stone or wood, or are easily moulded but do not retain the
shape impressed, like wool or a sponge, are not plastic. The last
group are said to be 'squeezable'. Things are 'squeezable' when they
can contract into themselves under pressure, their surface sinking
in without being broken and without the parts interchanging position
as happens in the case of water. (We speak of pressure when there
is movement and the motor remains in contact with the thing moved,
of impact when the movement is due to the local movement of the motor.)
Those bodies are subject to squeezing which have empty pores-empty,
that is, of the stuff of which the body itself consists-and that can
sink upon the void spaces within them, or rather upon their pores.
For sometimes the pores upon which a body sinks in are not empty (a
wet sponge, for instance, has its pores full). But the pores, if full,
must be full of something softer than the body itself which is to
contract. Examples of things squeezable are the sponge, wax, flesh.
Those things are not squeezable which cannot be made to contract upon
their own pores by pressure, either because they have no pores or
because their pores are full of something too hard. Thus iron, stone,
water and all liquids are incapable of being squeezed.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:11:58 am
Things are tractile when their surface can be made to elongate, for
being drawn out is a movement of the surface, remaining unbroken,
in the direction of the mover. Some things are tractile, e.g. hair,
thongs, sinew, dough, birdlime, and some are not, e.g. water, stone.
Some things are both tractile and squeezable, e.g. wool; in other
cases the two qualities do not coincide; phlegm, for instance, is
tractile but not squeezable, and a sponge squeezable but not tractile.

Some things are malleable, like copper. Some are not, like stone and
wood. Things are malleable when their surface can be made to move
(but only in part) both downwards and sideways with one and the same
blow: when this is not possible a body is not malleable. All malleable
bodies are impressible, but not all impressible bodies are malleable,
e.g. wood, though on the whole the two go together. Of squeezable
things some are malleable and some not: wax and mud are malleable,
wool is not. Some things are fissile, e.g. wood, some are not, e.g.
potter's clay. A thing is fissile when it is apt to divide in advance
of the instrument dividing it, for a body is said to split when it
divides to a further point than that to which the dividing instrument
divides it and the act of division advances: which is not the case
with cutting. Those bodies which cannot behave like this are non-fissile.
Nothing soft is fissile (by soft I mean absolutely soft and not relatively:
for iron itself may be relatively soft); nor are all hard things fissile,
but only such as are neither liquid nor impressible nor comminuible.
Such are the bodies that have the pores along which they cohere lengthwise
and not crosswise.

Those hard or soft solids are apt to be cut which do not necessarily
either split in advance of the instrument or break into minute fragments
when they are being divided. Those that necessarily do so and liquids
cannot be cut. Some things can be both split and cut, like wood, though
generally it is lengthwise that a thing can be split and crosswise
that it can be cut. For, a body being divided into many parts fin
so far as its unity is made up of many lengths it is apt to be split,
in so far as it is made up of many breadths it is apt to be cut.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:12:10 am
A thing is viscous when, being moist or soft, it is tractile. Bodies
owe this property to the interlocking of their parts when they are
composed like chains, for then they can be drawn out to a great length
and contracted again. Bodies that are not like this are friable. Bodies
are compressible when they are squeezable and retain the shape they
have been squeezed into; incompressible when they are either inapt
to be squeezed at all or do not retain the shape they have been squeezed
into.

Some bodies are combustible and some are not. Wood, wool, bone are
combustible; stone, ice are not. Bodies are combustible when their
pores are such as to admit fire and their longitudinal pores contain
moisture weaker than fire. If they have no moisture, or if, as in
ice or very green wood, the moisture is stronger than fire, they are
not combustible.

Those bodies give off fumes which contain moisture, but in such a
form that it does not go off separately in vapour when they are exposed
to fire. For vapour is a moist secretion tending to the nature of
air produced from a liquid by the agency of burning heat. Bodies that
give off fumes give off secretions of the nature of air by the lapse
of time: as they perish away they dry up or become earth. But the
kind of secretion we are concerned with now differs from others in
that it is not moist nor does it become wind (which is a continuous
flow of air in a given direction). Fumes are common secretion of dry
and moist together caused by the agency of burning heat. Hence they
do not moisten things but rather colour them.

The fumes of a woody body are called smoke. (I mean to include bones
and hair and everything of this kind in the same class. For there
is no name common to all the objects that I mean, but, for all that,
these things are all in the same class by analogy. Compare what Empedocles
says: They are one and the same, hair and leaves and the thick wings
of birds and scales that grow on stout limbs.) The fumes of fat are
a sooty smoke and those of oily substances a greasy steam. Oil does
not boil away or thicken by evaporation because it does not give off
vapour but fumes. Water on the other hand does not give off fumes,
but vapour. Sweet wine does give off fumes, for it contains fat and
behaves like oil. It does not solidify under the influence of cold
and it is apt to burn. Really it is not wine at all in spite of its
name: for it does not taste like wine and consequently does not inebriate
as ordinary wine does. It contains but little fumigable stuff and
consequently is inflammable.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:12:27 am
All bodies are combustible that dissolve into ashes, and all bodies
do this that solidify under the influence either of heat or of both
heat and cold; for we find that all these bodies are mastered by fire.
Of stones the precious stone called carbuncle is least amenable to
fire.

Of combustible bodies some are inflammable and some are not, and some
of the former are reduced to coals. Those are called 'inflammable'
which produce flame and those which do not are called 'non-inflammable'.
Those fumigable bodies that are not liquid are inflammable, but pitch,
oil, wax are inflammable in conjunction with other bodies rather than
by themselves. Most inflammable are those bodies that give off smoke.
Of bodies of this kind those that contain more earth than smoke are
apt to be reduced to coals. Some bodies that can be melted are not
inflammable, e.g. copper; and some bodies that cannot be melted are
inflammable, e.g. wood; and some bodies can be melted and are also
inflammable, e.g. frankincense. The reason is that wood has its moisture
all together and this is continuous throughout and so it burns up:
whereas copper has it in each part but not continuous, and insufficient
in quantity to give rise to flame. In frankincense it is disposed
in both of these ways. Fumigable bodies are inflammable when earth
predominates in them and they are consequently such as to be unable
to melt. These are inflammable because they are dry like fire. When
this dry comes to be hot there is fire. This is why flame is burning
smoke or dry exhalation. The fumes of wood are smoke, those of wax
and frankincense and such-like, and pitch and whatever contains pitch
or such-like are sooty smoke, while the fumes of oil and oily substances
are a greasy steam; so are those of all substances which are not at
all combustible by themselves because there is too little of the dry
in them (the dry being the means by which the transition to fire is
effected), but burn very readily in conjunction with something else.
(For the fat is just the conjunction of the oily with the dry.) So
those bodies that give off fumes, like oil and pitch, belong rather
to the moist, but those that burn to the dry.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:12:42 am
Part 10

Homogeneous bodies differ to touch-by these affections and differences,
as we have said. They also differ in respect of their smell, taste,
and colour.

By homogeneous bodies I mean, for instance, 'metals', gold, copper,
silver, tin, iron, stone, and everything else of this kind and the
bodies that are extracted from them; also the substances found in
animals and plants, for instance, flesh, bones, sinew, skin, viscera,
hair, fibres, veins (these are the elements of which the non-homogeneous
bodies like the face, a hand, a foot, and everything of that kind
are made up), and in plants, wood, bark, leaves, roots, and the rest
like them.

The homogeneous bodies, it is true, are constituted by a different
cause, but the matter of which they are composed is the dry and the
moist, that is, water and earth (for these bodies exhibit those qualities
most clearly). The agents are the hot and the cold, for they constitute
and make concrete the homogeneous bodies out of earth and water as
matter. Let us consider, then, which of the homogeneous bodies are
made of earth and which of water, and which of both.

Of organized bodies some are liquid, some soft, some hard. The soft
and the hard are constituted by a process of solidification, as we
have already explained.

Those liquids that go off in vapour are made of water, those that
do not are either of the nature of earth, or a mixture either of earth
and water, like milk, or of earth and air, like wood, or of water
and air, like oil. Those liquids which are thickened by heat are a
mixture. (Wine is a liquid which raises a difficulty: for it is both
liable to evaporation and it also thickens; for instance new wine
does. The reason is that the word 'wine' is ambiguous and different
'wines' behave in different ways. New wine is more earthy than old,
and for this reason it is more apt to be thickened by heat and less
apt to be congealed by cold. For it contains much heat and a great
proportion of earth, as in Arcadia, where it is so dried up in its
skins by the smoke that you scrape it to drink. If all wine has some
sediment in it then it will belong to earth or to water according
to the quantity of the sediment it possesses.) The liquids that are
thickened by cold are of the nature of earth; those that are thickened
either by heat or by cold consist of more than one element, like oil
and honey, and 'sweet wine'.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:13:02 am
Of solid bodies those that have been solidified by cold are of water,
e.g. ice, snow, hail, hoar-frost. Those solidified by heat are of
earth, e.g. pottery, cheese, natron, salt. Some bodies are solidified
by both heat and cold. Of this kind are those solidified by refrigeration,
that is by the privation both of heat and of the moisture which departs
with the heat. For salt and the bodies that are purely of earth solidify
by the privation of moisture only, ice by that of heat only, these
bodies by that of both. So both the active qualities and both kinds
of matter were involved in the process. Of these bodies those from
which all the moisture has gone are all of them of earth, like pottery
or amber. (For amber, also, and the bodies called 'tears' are formed
by refrigeration, like myrrh, frankincense, gum. Amber, too, appears
to belong to this class of things: the animals enclosed in it show
that it is formed by solidification. The heat is driven out of it
by the cold of the river and causes the moisture to evaporate with
it, as in the case of honey when it has been heated and is immersed
in water.) Some of these bodies cannot be melted or softened; for
instance, amber and certain stones, e.g. the stalactites in caves.
(For these stalactites, too, are formed in the same way: the agent
is not fire, but cold which drives out the heat, which, as it leaves
the body, draws out the moisture with it: in the other class of bodies
the agent is external fire.) In those from which the moisture has
not wholly gone earth still preponderates, but they admit of softening
by heat, e.g. iron and horn.

Now since we must include among 'meltables' those bodies which are
melted by fire, these contain some water: indeed some of them, like
wax, are common to earth and water alike. But those that are melted
by water are of earth. Those that are not melted either by fire or
water are of earth, or of earth and water.

Since, then, all bodies are either liquid or solid, and since the
things that display the affections we have enumerated belong to these
two classes and there is nothing intermediate, it follows that we
have given a complete account of the criteria for distinguishing whether
a body consists of earth or of water or of more elements than one,
and whether fire was the agent in its formation, or cold, or both.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:13:17 am
Gold, then, and silver and copper and tin and lead and glass and many
nameless stone are of water: for they are all melted by heat. Of water,
too, are some wines and urine and vinegar and lye and whey and serum:
for they are all congealed by cold. In iron, horn, nails, bones, sinews,
wood, hair, leaves, bark, earth preponderates. So, too, in amber,
myrrh, frankincense, and all the substances called 'tears', and stalactites,
and fruits, such as leguminous plants and corn. For things of this
kind are, to a greater or less degree, of earth. For of all these
bodies some admit of softening by heat, the rest give off fumes and
are formed by refrigeration. So again in natron, salt, and those kinds
of stones that are not formed by refrigeration and cannot be melted.
Blood, on the other hand, and semen, are made up of earth and water
and air. If the blood contains fibres, earth preponderates in it:
consequently its solidifies by refrigeration and is melted by liquids;
if not, it is of water and therefore does not solidify. Semen solidifies
by refrigeration, its moisture leaving it together with its heat.

Part 11

We must investigate in the light of the results we have arrived at
what solid or liquid bodies are hot and what cold.

Bodies consisting of water are commonly cold, unless (like lye, urine,
wine) they contain foreign heat. Bodies consisting of earth, on the
other hand, are commonly hot because heat was active in forming them:
for instance lime and ashes.

We must recognize that cold is in a sense the matter of bodies. For
the dry and the moist are matter (being passive) and earth and water
are the elements that primarily embody them, and they are characterized
by cold. Consequently cold must predominate in every body that consists
of one or other of the elements simply, unless such a body contains
foreign heat as water does when it boils or when it has been strained
through ashes. This latter, too, has acquired heat from the ashes,
for everything that has been burnt contains more or less heat. This
explains the generation of animals in putrefying bodies: the putrefying
body contains the heat which destroyed its proper heat.

Bodies made up of earth and water are hot, for most of them derive
their existence from concoction and heat, though some, like the waste
products of the body, are products of putrefaction. Thus blood, semen,
marrow, figjuice, and all things of the kinds are hot as long as they
are in their natural state, but when they perish and fall away from
that state they are so no longer. For what is left of them is their
matter and that is earth and water. Hence both views are held about
them, some people maintaining them to be cold and others to be warm;
for they are observed to be hot when they are in their natural state,
but to solidify when they have fallen away from it. That, then, is
the case of mixed bodies. However, the distinction we laid down holds
good: if its matter is predominantly water a body is cold (water being
the complete opposite of fire), but if earth or air it tends to be
warm.

It sometimes happens that the coldest bodies can be raised to the
highest temperature by foreign heat; for the most solid and the hardest
bodies are coldest when deprived of heat and most burning after exposure
to fire: thus water is more burning than smoke and stone than water.

Part 12

Having explained all this we must describe the nature of flesh, bone,
and the other homogeneous bodies severally.


Title: Re: Meteorology By Aristotle
Post by: Bathos on August 31, 2009, 12:13:53 am
Our account of the formation of the homogeneous bodies has given us
the elements out of which they are compounded and the classes into
which they fall, and has made it clear to which class each of those
bodies belongs. The homogeneous bodies are made up of the elements,
and all the works of nature in turn of the homogeneous bodies as matter.
All the homogeneous bodies consist of the elements described, as matter,
but their essential nature is determined by their definition. This
fact is always clearer in the case of the later products of those,
in fact, that are instruments, as it were, and have an end: it is
clearer, for instance, that a dead man is a man only in name. And
so the hand of a dead man, too, will in the same way be a hand in
name only, just as stone flutes might still be called flutes: for
these members, too, are instruments of a kind. But in the case of
flesh and bone the fact is not so clear to see, and in that of fire
and water even less. For the end is least obvious there where matter
predominates most. If you take the extremes, matter is pure matter
and the essence is pure definition; but the bodies intermediate between
the two are matter or definition in proportion as they are near to
either. For each of those elements has an end and is not water or
fire in any and every condition of itself, just as flesh is not flesh
nor viscera viscera, and the same is true in a higher degree with
face and hand. What a thing is always determined by its function:
a thing really is itself when it can perform its function; an eye,
for instance, when it can see. When a thing cannot do so it is that
thing only in name, like a dead eye or one made of stone, just as
a wooden saw is no more a saw than one in a picture. The same, then,
is true of flesh, except that its function is less clear than that
of the tongue. So, too, with fire; but its function is perhaps even
harder to specify by physical inquiry than that of flesh. The parts
of plants, and inanimate bodies like copper and silver, are in the
same case. They all are what they are in virtue of a certain power
of action or passion-just like flesh and sinew. But we cannot state
their form accurately, and so it is not easy to tell when they are
really there and when they are not unless the body is thoroughly corrupted
and its shape only remains. So ancient corpses suddenly become ashes
in the grave and very old fruit preserves its shape only but not its
taste: so, too, with the solids that form from milk.

Now heat and cold and the motions they set up as the bodies are solidified
by the hot and the cold are sufficient to form all such parts as are
the homogeneous bodies, flesh, bone, hair, sinew, and the rest. For
they are all of them differentiated by the various qualities enumerated
above, tension, tractility, comminuibility, hardness, softness, and
the rest of them: all of which are derived from the hot and the cold
and the mixture of their motions. But no one would go as far as to
consider them sufficient in the case of the non-homogeneous parts
(like the head, the hand, or the foot) which these homogeneous parts
go to make up. Cold and heat and their motion would be admitted to
account for the formation of copper or silver, but not for that of
a saw, a bowl, or a box. So here, save that in the examples given
the cause is art, but in the nonhomogeneous bodies nature or some
other cause.

Since, then, we know to what element each of the homogeneous bodies
belongs, we must now find the definition of each of them, the answer,
that is, to the question, 'what is' flesh, semen, and the rest? For
we know the cause of a thing and its definition when we know the material
or the formal or, better, both the material and the formal conditions
of its generation and destruction, and the efficient cause of it.

After the homogeneous bodies have been explained we must consider
the non-homogeneous too, and lastly the bodies made up of these, such
as man, plants, and the rest.

THE END

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