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and which causes the earth to open, that same thing causes the clouds to flash,
as one sees when there is thunder. For thunder and lightning
are nothing but the confrontation among winds that meet with
each other above the clouds so fiercely that their arrival often
causes fire to flare in the air. And lightning falls
in many places, constrained by the wind, so terribly that
the clouds crack and fall apart and cause thundering
and flashing, falling downward with such force that
it confounds anything it encounters, so that nothing can
hold out against it. And it is so heavy by nature that sometimes
it pierces the earth unto the core, but sometimes it extinguishes
itself before it hits the ground, when it is not
as strong. For when the cloud is very dark and thick and
there is a great deal of water in it, then as soon as the
fire passes through the cloud it is extinguished due to
the great quantity of water therein, so that even if it can
pierce the cloud it cannot reach the earth. But at the moment
it extinguishes, there arises in the cloud a sound so loud
that it is marvelous to hear. This, I tell you, is the thunder
that is much to be feared, just as when a hot and
burning iron, placed in a tub full of water