Spark gap n. (Elec.) The space filled with air or other dielectric between high potential terminals (as of an electrostatic machine, induction coil, or condenser), through which the discharge passes; the air gap of a jump spark.
... certain precautions are necessary. When he uses tin-foil electrodes on the outside of the bulb, he protects the tin-foil edges, and, what is more essential, uses extremely small Leyden jars and a short spark gap between the poles of the discharging rods. The philosophy of this is, that the smaller the jars, the greater their number of oscillations per second (easily fifteen million, according to Dr. Lodge's computations), the shorter the wave length, and, therefore, the greater ... — McClure's Magazine, Vol. 6, No. 5, April, 1896 • Various Read full book for free!