On 2015\10\14 17:22, Robin wrote:
Jarle Hammen Knudsen wrote:
From the particularly good blog World War II Today,
the entry for 14 October 1940:

I lived bear Balham for a few years in the late 1970s and a good few
locals had vivid stories of that night. And it wasn't just the tube
that suffered. Apart from the tramway, in the blackout a bus didn't
manage to mind the gap

http://www.dailymail.co.uk/news/arti...ld-War-II.html
(scroll down to 3rd and 4th photos)

Holes in the ground are often measured in DDBs (double decker buses)...
they don't usually use an actual bus to measure it though.