 Southall later published a version of this story for younger readers under the title "Seventeen Seconds" — the time available to run in case the fuse of the mine was accidentally triggered while trying to disarm it.From 1950 to 1962, Southall also wrote, for younger readers, adventure stories about a fictional brave pilot, 'Simon Black' — an Australian counterpart to W.E.Johns' hero 'Biggles'.