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FRANCE - APRIL 11: This ornate planetary model was made by the Parisian clock makers, Raingo Frères. Called an orrery, or more correctly a tellurium, it is a demonstration device to show the motions of the Earth and Moon around the Sun. It consists of a wooden drum base containing a music box, surmounted by a four-legged stand supporting the orrery and a timepiece. The spring driven pendulum clock drives the planetary model at the same rate as the heavens. A glass dome originally covered the whole mechanism. Such apparatus became popular during the 17th century, especially after Sir Isaac Newton (1642-1727) published his universal theory of gravity in 1687. Only about a dozen of these particular clocks were made, most of them for Royalty or Ministers of State. (Photo by SSPL/Getty Images)