In science, perpetual motion refers to any number of machines or mechanisms, often built using various mixtures of levers, water wheels, screws, gears, balls running down ramps, etc., conceived to create continuous motion or mechanical work endlessly without an external power source. [1] The dipping bird is kind of like a perpetual motion machine, a contraption that runs for weeks on end, albeit one that runs on atmospheric heat gradients.

All early perpetual motion machines were concerned with efforts to replace the work of the miller who used either water (waterpower) or wind (windpower) to grind corn. [5] Various modern-age perpetual motion devices continue to be made every year up to the present by individuals with dreams of solving the energy crisis. [3]

These devices were built endlessly, beginning in about the 8th century and over the following millennium, up until the invention of the steam engine by French physicist Denis Papin in 1691, which soon thereafter worked alleviate the hard work of the miller.

In 1775, the Paris Academy of Sciences made the decision not to examine inventions concerning perpetual motion engines. [1]


A popular example of an interesting perpetual motion machine is English physician Robert Fludd’s 1630s grain grinding machine which supposedly operated via a water recirculation using a water wheel and an Archimedean screw. A late 17th century version of Fludd's perpetual motion grain grinding machine, as shown in Böckler's Theatre of New Machines, is depicted adjacent.

Thermodynamics
With the rise of thermodynamics in the 1850s, through the work of Rudolf Clausius, a general disproof of the possible existence of perpetual motion machines was established.

A disproof of perpetual motion using the first law of thermodynamics defines perpetual motion of the first kind and disproof using the second law refers to perpetual motion of the second kind. The 1961 lithograph by Dutch artist M.C. Escher, as pictured, depicting water paradoxically running from the base of the waterfall uphill to the top of the waterfall, is said to be representative of perpetual motion of the first kind. [2] The phrase “perpetual motion of the second kind”, supposedly, was introduced by German physical chemist Wilhelm Ostwald. [4]

Biological perpetual motion
In recent decades, beginning generally with Belgian chemist Ilya Prigogine’s 1977 book Self-Organization in Non-Equilibrium Systems, in many thermodynamic explanations of biological processes or evolution the term “self-”, as in self-organizing, self-reproducing, self-activating, etc., are being used, which are akin to biological perpetual motion. These descriptions are typically found in origin of life discussions. An example is American biochemist Stuart Kauffman's 1995 theory of self-catalyzing looped chemical reactions that comes alive, seeming going on its own; which he equates to the threshold of the start of life in the evolution timeline. [6]

References
1. Perrot, Perrie. (1998). A to Z of Thermodynamics (pgs. 234-35). Oxford University Press.
2. Waterfall (M. C. Escher) – Wikipedia.
3. History of perpetual motion machines – Wikipedia.
4. Hokikian, Jack. (2002). The Science of Disorder: Understanding the Complexity, Uncertainty, and Pollution in Our World (pg. 24). Los Feliz Publishing.
5. Ord-Hume, Arthur W.J.G. and Ord, Hume A. (2006). Perpetual Motion: The History of an Obsession. Adventures Unlimited Press; St. Martin’s Press, 1977.
6. Kauffman, Stuart. (1995). At Home in the Universe - the Search for the Laws of Self-Organization and Complexity (pg. 50). Oxford: Oxford University Press.

Further reading
● Angrist, Stanley W. “Perpetual Motion Machines.” Scientific American, 218 (January, 1968): 114-22.

External links
● Perpetual motion – Wikipedia.
● Simanek, Donald E. (date). “Perpetual Futility: A Short History of the Search for Perpetual Motion”, Lock Haven University.