Makes you wonder if Magic Grandpa has tried to visit a submarine, all those Trots must have surely peaked his interestFirstly, a bit of background. On a boat when alongside, there is a sentry up top by the Main Access hatch (the hole by which one enters a submarine). He is armed and is known as the Upper Deck Trot. There is another chap in the Control Room, who keeps an eye on things inside, known as the Lower Deck Trot. Looks at dials and answers phones.
There are 2 telephone landlines, one to the Skipper's cabin and a general one in the Control Room.
As you all know, when answering a phone, if a squeaky voice asks for Chief X, the correct response is NOT 'Oh, is that his wife?' .........Unless you are a brand new out the box sprog.
When chaps on a boat are having 'marital problems' the standard response to an unwanted squeaky voice call is 'sorry love, he's under the casing / in the dockyard' thus denying availability of Chief X.
So it came to pass that during my divorce proceedings, having cunningly avoided contact with the ex, who knew all the dodges, her being a Wren, I'm in the Control Room when the phone rang.
'Hello, submarine XXX'
'Yes, love, he's standing right beside me'
Her 'Not under the casing then...
Top Lower Deck Trot!