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1908 J. H. Adams in Onker & Baker Harper's How to understand Electr. Work 340/2 Jump-spark, a disruptive spark excited between two conducting surfaces in distinction from a spark excited by a rubbing contact.

1911 Daily Colonist (Victoria, Brit. Columbia) 20 Apr. 8/1 A regal Marine Engine... Jump spark or make-and-break ignition.

1922 A. F. Collins Bk. Wireless Telegr. & Telephone i. 6 The spark-coil, or induction coil,..is used to change the battery current into a current of high pressure to make jump sparks.

1938 A. W. Judge Automobile Electr. Maintenance ii. 27 A brass plate at the end of the arm..passes very close to the brass contacts..as it rotates, so that a spark leaps across the small air gap. This is known as the jump spark method.

1963 A. Bird & F. Hutton-Stott Veteran Motor Car Pocketbk. 8 ‘Jump-spark’ ignition in American usage generally, though not always, referred to high tension coil and battery apparatus with a mechanical contact-breaker and non-trembling coil, but in English usage, at one time, ‘jump-spark ignition’ meant any form of H.T. ignition with spark-gaps or ‘intensifiers’ included in the circuit.