The Wimshurst machine is an electrostatic evice for generating high voltages developed between 1880 and 1883 by British inventor James Wimshurst (1832 – 1903). It has a distinctive appearance with two large contra-rotating discs mounted in a vertical plane, two cross bars with metallic brushes, and a spark gap formed by two metal spheres. It is based on the triboelectric effect, where charge accumulates when two dissimilar materials rub against one another.