X-ray apparatus consisting induction coil by Alfred Apps, London, X-ray tube stand and cold cathode X-ray tube, British, 1896-1910

Before mains electricity was reliably available, electric power in the form of a spark was generated using an induction coil. The coil was patented by scientific instrument maker Alfred Apps in 1867 and this example dates from the 1890s or 1900s. It was used with an X-ray tube. This coil also has a hammer-break interrupter. This device periodically and automatically opens and closes an electric circuit to produce pulses of power.