Together with the Magdeburg hemispheres a fountain of Hero and an inclined plane for mechanical experiments, this is probably one of the instruments that Father Giovanni Antonio Cossu, of the Servants of Mary, received from Charles Emmanuel III for use in the Physics Laboratory of the Royal University of Cagliari. In the note accompanying the machines that Father Cossu received it is indicated as: Inclined plane with two wooden cones joined at the bases which roll along the plane.