Some discussion by Aussie academic Brett Holman on Waiting for Hitler: Voices from Britain on the Brink of Invasion by Midge Gillies

http://airminded.org/2008/01/26/the-day-of-the-parashot/

One of the aspects of Waiting for Hitler I appreciated was Gillies’ attention to rumours and panics as an index of the insecurity of the British people as they prepared for a possible German invasion. These are fascinating. For example, the slit trenches being dug in Hyde Park were said to be for mass burials in the aftermath of air raids, not protection from bombs. Troops practicing machine-gunning a buoy in a Cornish harbour turned into the accidental death of a boy by machine-gun fire the next day, and then the massacre of dozens of children on the beach the next, strafed by German aeroplanes.