German, C.1900, unsigned, turned wooden base with terminals for low voltage to motor and high voltage to Geissler tube, brass column supports soft iron ring, bobbin wound coils to the rotor, breaker to the rear, height 33cm

Reference: For a similar instrument see: http://physics.kenyon.edu/EarlyApparatus/Electric_Motors/Wheatstones_motor/Wheatstones_Motor.html