science · 30 April 1939 · 85 years ago
In 1939, cosmic rays entering a Geiger-Mueller counter produced electrical impulses used to control electrical power. This first ever such event, was used for the illumination ceremony of the 1939 New York World's Fair. The counter, at the Hayden Planetarium, New York City, switched on an electrical circuit wired to a display at the Lagoon of Nations where relays activated local battery circuits ringing bells and flashing lights to signal each capture of a cosmic ray. Albert Einstein as guest speaker explained cosmic rays. Sadly his accent and faulty amplification made his words incomprehensible to the crowd. Upon the tenth ray's signal, a huge light was to be turned on to illuminate the 600-ft Trylon triangular spire, but the power source failed.
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