Today, let's talk about wind and the medieval mind.
The University of Houston's College of Engineering
presents this series about the machines that make
our civilization run, and the people whose
ingenuity created them.
What, in the mind of a
medieval millwright, drove his mill? What invisible
efficacy was taken from the wind to grind grain?
The wind, after all, captures our imaginations
strongly enough when we know about air, and kinetic
energy, and force balances.
A little word-game gives us a startling insight.
The ancient tongues all used the same word for
wind, for breath, and for soul. In Sanskrit that
word is atman, in Latin it's either
spiritus or anima, in
Hebrew it's rauch, and in Greek it's
pneuma. Rauch shows up
again as the German word for smoke, and you see
pneuma in air-related words like
pneumatic. The Russian word for spirit,
duh, has many wind-related cognates.
Duhovyia intrumenti, for example,
means wind instruments.
The connection is that both the wind and the soul
were the breath of God. Genesis, for example,
begins with God breathing a soul into Adam.
Medieval engineers saw nothing less blowing their
windmills. The power source was mystical. By the
way, some historians are pretty sure that the
windmill itself was derived from ancient Buddhist
prayer wheels -- spun by sail-like propellers.
We can describe the wind in technical terms today;
but it hasn't lost its metaphorical power. The
19th-century naturalist poet Shelley shouted at the
west wind,
. . . Be thou, Spirit fierce, My spirit! Be
thou me, impetuous one! Drive my dead thoughts
over the universe, Like wither'd leaves, to
quicken new birth.
His wind wasn't just
spiritus -- it was a renewing spirit --
a cleansing new broom -- the same imagery we use when
we tell each other, "It's an ill wind that blows no
good."
The world is girdled with a prevailing wind
pattern. The first time you fly to London you're
startled to find that New York is two hours farther
from London than London is from New York, because
Shelley's westerlies prevail in a band around the
45th parallel. Below the westerlies, northeasterly
trade winds blow down to an equatorial band that's
almost devoid of wind. These waters are called the
"horse latitudes" because sailors on ships becalmed
in them had to kill any horses on board to save
water. Of course, they're also called the doldrums,
which means disspirited.
The possible return to wind power is a new wind
that's blowing through our technology. I have a
friend who teaches energy engineering at UCLA. He's
bought a power-generating windmill on a
windmill-farm in California. He goes out to see it.
All he tells me is that it's pretty; but I'm
inclined to think that the attraction is more
fundamental than that.
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds
work.
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