Clausius Tower

Foucault Pendulum

Paul Babtiste Foucault was a French scientist who lived from 1819 – 1868. He was one of the first who measured the speed of light in air and water, built a polarization prism, photometer and gyroscope. He is mostly famous for his experiments with a pendulum, which proved that the Earth rotates on its axis.

In his cellar he had suspended a shot weighing 5kilograms on a wire 2metres long and noticed that the surface of the pendulum motion was rotating systematically.

In 1851 Foucault conducted this experiment again in the Pantheon in Paris. he then used a pendulum in the shape of shot weighting 28kilograms and a cord 67metres long. The pendulum was set in motion and after some time Foucault noticed that movements of the shot were marking rosete. This is proof that the Earth rotates on its axis.

Currently there are several hundred Foucault pendulums in the world. Due to their spectacular dimension and impressive appearance they are located in places important to science, culture and policy, such as universities, museums and congress centers. Most of Foucault pendulums are built in the USA for example in Congress Centre in Portland, in the Museum of Science and Industry in Chicago, in the National Museum of American History in Washington. In Europe pendulums can be found in the Basilica of St Peter's in Rome, in the mentioned Pantheon in Paris and in the Science Museum in Wien. In Poland pendulums are built at The Faculty of Physics at the Adam Mickiewicz University, in St. Paul and Peter’s Church in Cracow, in the Tower of Radziejowski in Frombork and in The Pomeranian Dukes' Castle in Szczecin. Soon to be placed on the list of Polish Foucault Pendulums will the newest one, which will be built at The Technical University in Koszalin.