Science, experimentation and measurement

  • Ramsden static electricity machine

    Record number:  3137 
    Dimensions: 143 x 127 x 58 cm

    Static electricity machine with a glass disc, known as a Ramsden machine, on a wooden table. It comprises a fixed glass disc with a metal axle in the centre, rotated by means of a handle. As the glass passes through two wooden struts or parts supporting the axle, the surface rubs against the two bearings on the struts. The rotating movement serves to electrify the glass disc, which receives a positive electrical charge on both sides. A long transversal brass cylinder is the isolating conductor, on two glass feet. The far ends of the cylinder have two gilded arms, which end in points which almost touch the disc, discharging the electricity without rubbing.