For generating static electric charges and causing electric discharges. Relative to Van de Graaf it produces higher current with lower voltage. Consists of two high resistance plastic disks of diameter 25mm approx, with equally spaced metal sectors. The discs are supported in two rigid upright supports, rotating in opposite directions with a hand crank. Provided with a system of induced charge collecting brushes, adjustable ball-ended electrodes and cylindrical Leyden jar capacitors for obtaining higher potential. Produces substantial opposite charges which are deposited in the capacitors and on metal spheres. A rapid sequence of sparks can be generated by lowering the system’s capacitance. Mounted on insulated wooden base.