In the night of April 11-12, 1931 the first demostration of Foucault's pendulum took place
The exeriment was performed in St. Isaac's Cathedral (where an antireligious museum was located at the time). About seven thousand people gathered for the demostration. Afterwards the Foucault's pendulum had long been a part of the exposition. It was removed in 1986 and now is stored in the cellars of the cathedral.
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