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Salt Water Dimmers
water dimmers Salt water dimmers, which are an example of liquid rheostats, were used in theatres after the introduction of electric lighting to control the brightness of the lights on stage. Electric Lighting[edit] Electric lighting replaced gas in theatres from the 1880s.
Original salt water dimmers mounted on the wall in the wings of Alexandra Palace Theatre. A dimmer consisted of a glass jar filled with salt water with a metal electrode at each end. The salt water need to be refilled regularly, the metal electrodes corroded, and the dimmers emitted a strong smell.
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