I had some comments from readers so I have made a couple of changes:
Firstly, pointed out to me by several readers, there was a sentence which described the contents of a picnic as it was done in 'Wind in the Willows' without spacing. It worked for Kenneth Graham, but it didn't work for me!
I have also corrected misinformation regarding the engines in PT boats. Not essential to the story, but it was wrong. Thanks to zzatz for that