In reply to:

Obviously, this was in the days when milkmen in horse-drawn milk trucks delivered bottled milk to doorsteps in every residential neighbourhood. That dates the research back at least 50 years, I fathom.

Has there been a major social upheaval while I've been away? As far as I know milk in the UK is still delivered door-to-door using electric carts.

See the vehicle on the left on this page:
http://www.milkbottlenews.org.uk/photos/dairyvehicles.html

Some interesting examples of notes to the milkman:
http://www.milkbottlenews.org.uk/features/notes/index.html

Bingley


Bingley