Duration of Electric Spark

Wheatstone determined the duration of the spark given by a Leyden jar as 1/24000 second. Feddersen by interposing a tube of water 9 millimeters (.36 inch) long in its path found that it lasted 14/10000 second, and with one 180 millimeters (7.2 inches) long, 188/10000 second. Lucas and Cazin for a 5 millimeter (.2 inch) spark, with different numbers of Leyden jars, found the following:
  Number of jars.  Duration of Spark.
    2             .000026 second
    4             .000041 "
    6             .000045 "
    8             .000047 "

The duration increases with the striking distance, and is independent of the diameter of the balls between which it is produced.