UXB

Part of the Museum was devoted to WW2, and the entrance was mocked up with sandbags and a sign announcing: 'Keep Clear: Unexploded Bomb!'

It took me a few minutes, and the help of one of the Museum Guides, to convince Wilson that this was just pretend — there wasn't really an unexploded bomb. 

Once he was convinced of this, he donned a Tin Helmet and entered into the spirit of things, examining all the exhibits with interest.

I'm pretty sure, though, that WW2 is confused in his mind with the Great Ant Wars of 1921 in which his ancestor 'The Blue Baron' was a distinguished fighter pilot…