sit, crank

Wood, steel, and electrical equipment

Two chairs are placed on opposite sides of a center mechanism. One chair faces a stolen red light bulb and normally leans in a forward position. The other chair faces a hand crank and normally leans back. A propeller shaft rests on a pressure switch in the center mechanism. When two viewers occupy the chairs and lean in the appropriate directions they partially complete a circuit. If the propeller is cranked fast enough it creates enough lift to release the pressure switch and momentarily shine the light on the passive sitters face. If either viewer gets up, or if the propeller stops, the light will fail to shine.

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