TOURBILLON
Tourbillon
In horology, a tourbillon is an addition to the mechanics of a watch escapement. Developed around 1795 by the French-Swiss watchmaker Abraham-Louis Breguet from an earlier idea by the English chronometer maker John Arnold, a tourbillon aims to counter the effects of gravity by mounting the escapement and balance wheel in a rotating cage, to negate the effect of gravity when the timepiece is stuck in a certain position.The above text is a snippet from Wikipedia: Tourbillon
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