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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。
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。
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 a