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The magic dance of Heron (1st c. A.D.)

It consisted of an altar with a transparent pedestal inside which was a circular disc with dancers. The
disc rotation axle was placed at the base of the pedestal, penetrating the altar and at its top had an inverted funnel-like cover with horizontal bent pipes adapted in radial disposition. The exhaust fumes of the altar moved ascendantly, entered the funnel and came out from the bent pipes causing, because of the reaction, reverse rotation of the disc and consequently the dancing of the figures.