The invention of autonomous control, like most inventions, has
roots in ancient China. There, on a dusty windswept plain, a small
wooden statue of a man in robes teeters upon a short pole. The pole is
carried between a pair of turning wagon wheels, pulled by two red horses
outfitted in bronze finery.
The statue man, carved in the flowing dresses of 9th-century China,
points with outstretched hand towards a distant place. By the magic of
noisy gears connecting the two wooden wheels, as the cart races along
the steppes, the wooden man perched on the stick invariably, steadily,
without fail, points south. When the cart turns left or right, the
geared wheels calculate the change and swing the wooden man's (or is it
a god's?) arm a corresponding amount in the opposite direction, negating
the cart's shift and keeping the guide forever pointing to the south.
With an infallible will, and on his own accord, the wooden figure
automatically seeks south. The south-pointing chariot precedes a lordly
procession, preventing the party from losing its way in the desolate
countryside of old China.
How busy was the ingenious medieval mind of China! Peasant folk in the
backwaters of southwestern China, wishing to temper the amount of wine
downed in the course of a fireside toast, came upon a small device
which, by its own accord, would control the rowdy spirits of the wine.
Chou Ch'u-Fei, a traveler among the Ch'i Tung natives then, reported
that drinking bouts in this kingdom had been perfected by means of a
two-foot-long bamboo straw which automatically regulated wine
consumption, giving large-throated and small-mouthed drinkers equal
advantage. A "small fish made of silver" floated inside the straw. The
downward weight of the internal metal float restricted the flow of warm
plum wine if the drinker sucked too feebly (perhaps through
intoxication), thereby calling an end for his evening of merriment. If
he inhaled too boisterously, he also got nothing, as the same float
became wedged upwards by force of the suction. Only a temperate, steady
draw was profitable.
Upon inspection, neither the south-pointing carriage nor the wine straw
are truly automatic in a modern (self-steering) sense. Both devices
merely tell their human masters, in the most subtle and unconscious way,
of the adjustment needed to keep the action constant, and leave the
human to make the change in direction of travel or power of lung. In the
lingo of modern thinking, the human is part of the loop. To be truly
automatic, the south-pointing statue would have to turn the cart itself,
to make it a south-heading carriage. Or a carrot would have to be
dangled from the point of his finger so that the horses (now in the
loop) followed it. Likewise the drinking straw would have to regulate
its volume no matter how hard one sucked. Although not automatic, the
south-pointing cart is based on the differential gear, a
thousand-year-old predecessor to the automobile transmission, and an
early prototype of modern self-pointing guns on an armored tank which
aid the drivers inside where a magnetic compass is useless. Thus, these
clever devices are curious stillbirths in our genealogy of automation.
The very first truly automatic devices had actually been built long
before, a millennia earler.
Ktesibios was a barber who lived in Alexandria in the first half of the
third century B.C. He was obsessed with mechanical devices, for which he
had a natural genius. He eventually became a proper mechanician -- a
builder of artifactual creations -- under King Ptolemy II. He is credited
with having invented the pump, the water organ, several kinds of
catapults, and a legendary water clock. At the time, Ktesibios's fame as
an inventor rivaled that of the legendary engineer Archimedes. Today,
Ktesibios is credited with inventing the first honest-to-goodness
automatic device.
Ktesibios's clock kept extraordinarily good time (for then) by
self-regulating its water supply. The weakness of most water clocks
until that moment was that as the reservoir of water propelling the
drive mechanism emptied, the speed of emptying would gradually decrease
(because a shallow level of water provides less pressure than a high
level), slowing down the clock's movements. Ktesibios got around this
perennial problem by inventing a regulating valve (regula) comprised of
a float in the shape of a cone which fit its nose into a mating inverted
funnel. Within the regula, water flowed from the funnel stem, over the
cone, and into the bowl the cone swam in. The cone would then float up
into the concave funnel and constrict the water passage, thus throttling
its flow. As the water diminished, the float would sink, opening the
passage again and allowing more water in. The regula would immediately
seek a compromise position where it would let "just enough" water for a
constant flow through the metering valve vessel.
Ktesibios's regula was the first nonliving object to self-regulate,
self-govern, and self-control. Thus, it became the first self to be
born outside of biology. It was a true auto thing -- directed from within.
We now consider it to be the primordial automatic device because it held
the first breath of lifelikeness in a machine.
It truly was a self because of what it displaced. A constant
autoregulated flow of water translated into a constant autoregulated
clock and relieved a king of the need for servants to tend the water
clock's water vessels. In this way, "auto-self" shouldered out the human
self. From the very first instance, automation replaced human work.
Ktesibios's invention is first cousin to that all-American 20th-century
fixture, the flush toilet. Readers will recognize the Ktesibios floating
valve as the predecessor to the floating ball in the upper chamber of
the porcelain throne. After a flush, the floating ball sinks with the
declining water level, pulling open the water valve with its metal arm.
The incoming water fills the vessel again, raising the ball triumphantly
so that its arm closes the flow of water at the precise level of "full."
In a medieval sense, the toilet yearns to keep itself full by means of
this automatic plumbing. Thus, in the bowels of the flush toilet we see
the archetype for all autonomous mechanical creatures.
About a century later, Heron, working in the same city of Alexandria,
came up with a variety of different automatic float mechanisms, which
look to the modern eye like a series of wildly convoluted toilet
mechanisms. In actuality, these were elaborate party wine dispensers,
such as the "Inexhaustible Goblet" which refilled itself to a constant
level from a pipe fitted into its bottom. Heron wrote a huge
encyclopedia (the Pneumatica) crammed with his incredible (even by
today's standards) inventions. The book was widely translated and copied
in the ancient world and was influential beyond measure. In fact, for
2,000 years (that is, until the age of machines in the 18th century), no
feedback systems were invented that Heron had not already fathered.
The one exception was dreamed up in the 17th century by a Dutch
alchemist, lens grinder, pyromaniac, and hobby submariner by the name of
Cornelis Drebbel. (Drebbel made more than one successful submarine dive
around 1600!) While tinkering in his search for gold, Drebbel invented
the thermostat, the other universal example of a feedback system. As an
alchemist, Drebbel suspected that the transmutation of lead into gold in
a laboratory was inhibited by great temperature fluctuations of the heat
sources cooking the elements. In the 1620s he jerry-rigged a minifurnace
which could bake the initial alchemic mixture over moderate heat for a
very long time, much as might happen to gold-bearing rock bordering the
depths of Hades. On one side of his ministove, Drebbel attached a glass
tube the size of a pen filled with alcohol. The liquid would expand when
heated, pushing mercury in a connecting second tube, which in turn would
push a rod that would close an air draft on the stove. The hotter the
furnace, the futher the draft would close, decreasing the fire. The
cooling tube retracted the rod, thus opening the draft and increasing
the fire. An ordinary suburban tract home thermostat is conceptually
identical -- both seek a constant temperature. Unfortunately, Drebbel's
automatic stove didn't make gold, nor did Drebbel ever publish its
design, so his automatic invention perished without influence, and its
design had to be rediscovered a hundred years later by a French
gentleman farmer, who built one to incubate his chicken eggs.
James Watt, who is credited with inventing the steam engine, did not.
Working steam engines had been on the job for decades before Watt ever
saw one. As a young engineer, Watt was once asked to repair a
small-scale model of an early working, though inefficient, Newcomen
steam engine. Frustrated by its awkwardness, Watt set out to improve it.
At about the time of the American Revolution, he added two things to the
existing engines; one of them evolutionary, the other revolutionary. His
key evolutionary innovation was separating the heating chamber from the
cooling chamber; this made his engine extremely powerful. So powerful
that he needed to add a speed regulator to moderate this newly unleashed
machine power. As usual Watt turned to what already existed. Thomas
Mead, a mechanic and miller, had invented a clumsy centrifugal regulator
for a windmill that would lower the millstone onto the grain only when
stone's speed was sufficient. It regulated the output but not the power
of a millstone.
Watt contrived a radical improvement. He borrowed Mead's regulator from
the mill and revisioned it into a pure control circuit. By means of his
new regulator the steam machine gripped the throat of its own power. His
completely modern regula automatically stabilized his now ferocious
motor at a constant speed of the operator's choice. By adjusting the
governor, Watt could vary the steam engine to run at any rate. This was
revolutionary.
Like Heron's float and Drebbel's thermostat, Watt's centrifugal governor
is transparent in its feedback. Two leaden balls, each at the end of a
stiff pendulum, swing from a pole. As the pole rotates the balls spin
out levitating higher the faster the system spins. Linkages scissored
from the twirling pendulums slide up a sleeve on the pole, levering a
valve which controls the speed of rotation by adjusting the steam. The
higher the balls spin, the more the linkages close the valve, reducing
the speed, until an equilibrium point of constant rpms (and height of
spinning balls) is reached. The control is thus as dependable as
physics.
Rotation is an alien power in nature. But among machines, it is blood.
The only known bearing in biology is at the joint of a sperm's spinning
hair propeller. Outside of this micromotor, the axle and wheel are
unknown to those with genes. To the ungened machine, whirling wheels and
spinning shafts are reasons to live. Watt gave machines the secret to
controlling their own revolutions, which was his revolution. His
innovation spread widely and quickly. The mills of the industrial age
were fueled by steam, and the engines earnestly regulated themselves
with the universal badge of self-control: Watt's flyball governor.
Self-powered steam begat machine mills which begat new kinds of engines
which begat new machine tools. In all of them, self-regulators dwelt,
fueling the principle of snowballing advantages. For every one person
visibly working in a factory, thousands of governors and self-regulators
toiled invisibly. Today, hundreds of thousands of regulators, unseen,
may work in a modern plant at once. A single human may be their
coworker.
Watt took the volcanic fury of expanding steam and tamed it with
information. His flyball governor is undiluted informational control,
one of the first non-biological circuits. The difference between a car
and an exploding can of gasoline is that the car's information -- its
design -- tames the brute energy of the gas. The same amount of energy and
matter are brought together in a car burning in a riot and one speeding
laps in the Indy 500. In the latter case, a critical amount of
information rules over the system, civilizing the dragon of fire. The
full heat of fire is housetrained by small amounts of self-perception.
Furious energy is educated, brought in from the wilds to work in the
yard, in the basement, in the kitchen, and eventually in living rooms.
The steam engine is an unthinkable contraption without the domesticating
loop of the revolving governor. It would explode in the face of its
inventors without that tiny heart of a self. The immense surrogate slave
power released by the steam engine ushered in the Industrial Revolution.
But a second, more important revolution piggybacked on it unnoticed.
There could not have been an industrial revolution without a parallel
(though hidden) information revolution at the same time, launched by the
rapid spread of the automatic feedback system. If a fire-eating machine,
such as Watt's engine, lacked self-control, it would have taken every
working hand the machine displaced to babysit its energy. So
information, and not coal itself, turned the power of machines useful
and therefore desirable.
The industrial revolution, then, was not a preliminary primitive stage
required for the hatching of the more sophisticated information
revolution. Rather, automatic horsepower was, itself, the first phase of
the knowledge revolution. Gritty steam engines, not teeny chips, hauled
the world into the information age.
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