Unless I'm very much mistaken, it was John Rowland
), in message
who said:
"Ben Nunn" wrote in message
...

If the map has White City on the Central Line (as opposed
to Wood Lane) then it's post-1947. If Tooting Bec is no
longer called Trinity Road, then it's post-1950.

Since there are maps currently sold which show Aldwych station and
Southwark station as both open, you would have to correlate a lot of
different bits of evidence before you could be reasonably certain of
the date of a historic map.


Indeed.

I suppose that realistically one cannot tell how old a map is, only how new
it is - e.g. it's newer than the most recent addition reflected on the map.

Thus a map sold now can show Aldwych as being open, but a map from when
Aldwych was open will never show Southwark - e.g. Southwark on a map means
it's newer than 1999, but Aldwych on a map doesn't necessarily mean it's old
than 1994.

In this case we can look for positive changes - White City, Trinity Road
etc. to determine that the map is newer than NNNN date, but cannot rely on
the negative changes - the presence of South Action.

BTN