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causes a very great sound, or when one extinguishes
hot coals. But the lightning that comes from the thunder
appears first and then you hear the sound, because human
sight is keener than hearing. So it is when
one sees across the water (see note) cloth being beaten or a hammer
striking, one first sees the blow landed by the one doing it,
and then one hears the sound of the blow. In the same way
I can tell you about thunder, that one sees it before
one has heard it. And since it is so far above us, so much
greater is the gap between the sound and the flash, and after
one has seen it, then one hears its force. But the sooner
one hears the sound after the flash, the closer the thunder is.
[rubric:] In order to know how winds come to be. [/rubric]
One can understand the winds by considering the seas.
For the [sea's waters] often flow all around the earth
and collide with each other in some places so fiercely
that they rise along the side of a mountain and
force themselves into the air above it, and the air that is
forced out from that place pushes other air
in such a way that it returns rearward, roaring and undulating
like flowing water. For wind is nothing other than