260
PHVSICS OF THE IMPOSSIBLE
the very limit. The energy available to a single individual is now measured in thousands of horsepower. We take for granted that a single car
can generate hundreds of horsepower. Not surprisingly, this demand
for more and more energy has sparked an interest in greater sources
of energy, including perpetual motion machines.
PERPETUAL MOTION MACHINES THROUGH
HISTORY
The search for a perpetual motion machine is an ancient one. The first
recorded attempt to build a perpetual motion machine dates back to
the eighth century in Bavaria. It was a prototype for hundreds of variations to come for the next thousand years; it was based on a series of
small magnets attached to a wheel, like a Ferris wheel. The wheel was
placed on top of a much larger magnet on the floor. As each magnet on
the wheel passed over the stationary magnet, it was supposed to be attracted then repelled by the larger magnet, thereby pushing the wheel
and creating perpetual motion.
Another ingenious design was devised in 1150 by the Indian
philosopher Bhaskara, who proposed a wheel that would run forever
by adding a weight to the rim, causing the wheel to spin because it was
unbalanced. Work would be done by the weight as it made a revolution, and then it would return to its original position. By iterating this
over and over again, Bhaskara claimed that one could extract unlimited work for free.
The Bavarian and the Bhaskara designs for perpetual motion machines and their many descendants all share the same ingredients: a
wheel of some sort that can make a single revolution without the addition of any energy, producing usable work in the process. (Careful
examination of these ingenious machines usually shows that energy is
actually lost in each cycle, or that no usable work can be extracted.)
The coming of the Renaissance accelerated proposals for a perpetual motion machine. In 1635 the first patent was granted for a perpetual motion machine. By 1712 Johann Bessler had analyzed some three
hundred different models and proposed a design of his own. (Accord-
PHVSICS OF THE IMPOSSIBLE
the very limit. The energy available to a single individual is now measured in thousands of horsepower. We take for granted that a single car
can generate hundreds of horsepower. Not surprisingly, this demand
for more and more energy has sparked an interest in greater sources
of energy, including perpetual motion machines.
PERPETUAL MOTION MACHINES THROUGH
HISTORY
The search for a perpetual motion machine is an ancient one. The first
recorded attempt to build a perpetual motion machine dates back to
the eighth century in Bavaria. It was a prototype for hundreds of variations to come for the next thousand years; it was based on a series of
small magnets attached to a wheel, like a Ferris wheel. The wheel was
placed on top of a much larger magnet on the floor. As each magnet on
the wheel passed over the stationary magnet, it was supposed to be attracted then repelled by the larger magnet, thereby pushing the wheel
and creating perpetual motion.
Another ingenious design was devised in 1150 by the Indian
philosopher Bhaskara, who proposed a wheel that would run forever
by adding a weight to the rim, causing the wheel to spin because it was
unbalanced. Work would be done by the weight as it made a revolution, and then it would return to its original position. By iterating this
over and over again, Bhaskara claimed that one could extract unlimited work for free.
The Bavarian and the Bhaskara designs for perpetual motion machines and their many descendants all share the same ingredients: a
wheel of some sort that can make a single revolution without the addition of any energy, producing usable work in the process. (Careful
examination of these ingenious machines usually shows that energy is
actually lost in each cycle, or that no usable work can be extracted.)
The coming of the Renaissance accelerated proposals for a perpetual motion machine. In 1635 the first patent was granted for a perpetual motion machine. By 1712 Johann Bessler had analyzed some three
hundred different models and proposed a design of his own. (Accord-