Léon Foucault (1819-1868)
invented a pendulum that demonstrates the effect of the Earth's rotation. It's
first public exhibition was in Paris in 1851. There are many types of his pendulum on display all over the world today.
Eise Eisinga (1744-1828) Dutch amateur astronomer,
installed a Planetarium on the ceiling of his living room in his house in Franeker, Netherlands, finished in the year 1781. You can still visit his quaint house today to see the oldest working planetarium in the world.
