Editing Perpetual motion (section)

==History==
{{Main|History of perpetual motion machines}}
The history of perpetual motion machines dates back to the Middle Ages.<ref name="Lynn Townsend White 1960 p. 522-526">[[Lynn Townsend White, Jr.]] (April 1960). "Tibet, India, and Malaya as Sources of Western Medieval Technology", ''The American Historical Review'' '''65''' (3), p. 522-526.</ref> For millennia, it was not clear whether perpetual motion devices were possible or not, until the development of modern theories of thermodynamics showed that they were impossible. Despite this, many attempts have been made to create such machines, continuing into modern times.<ref>Graham Jenkin, ''Conquest of the Ngarrindjeri'' (1979), pp. 234-236, {{ISBN|0-7270-1112-X}}</ref> Modern designers and proponents often use other terms, such as "over unity",<ref>https://www.inventorsdigest.com/articles/spinning-their-wheels/, quoting Former US Patent Office Chief of Staff Don Kelly in relation to [[Newman's energy machine]]</ref> to describe their inventions.