Being of an age well past my biblically allotted three-score years and ten, I tend to reminisce as I drift off in my obligatory afternoon siesta. In this twilight zone, I remember days of youth, living in post-war London in the 1950s.

It was a cold, black-and-white time; the world was going through a 30-year period of global cooling and winters were harsh, with regular falls of snow interrupting everyday life and adding to the monochrome existence.