It’s some time ago now, but there was a fashion for drinking the rare black lichen. I say drinking because they used to dry it over open fires, grind it fine and mix it in almost pure spirit. It was strange stuff; it could give you strange dreams or even stranger nightmares.

Some artists of various sorts claimed it transported them to strange worlds beyond the imagination and the revelations they received inspired their finest work. For myself I merely comment that the time I drank three glasses of the stuff I couldn’t do any useful work for three days after it (and couldn’t see properly for two of them.) Others have told me that the main effect it had on them was to loosen the bowels rather than the chains of imagination.

But still the authorities banned it. Just why is something of a mystery. Personally I was quite…