[Arts et Metiers] Gyroscope of Foucault 1892. By inventing the gyroscope, Leon Foucault intended to make a device that would, literally, show the earth "turning around". The axis of the bronze torus, launched at high speed, aims ar a fixed direction in space, and thanks to the microscope mounted on the instrument, the user can observe the rotation of the earth directly.
aperture=f2.8 focal length: 60.0 mm exposure 0.3 sec ISO: 800