Flanders and Swann, the At the Drop of a Hat song-writing duo, were close to Sydney Carter and their live shows often included a Carter song. Thus it is that "Hat-Trick," the package with four compact discs, has a live performance of Donald Swann singing the song on this thread, changing the phone-box location to his own neighborhood, spitting out "a filthy old phone box in Battersea Park."

Leon Berger, the keeper of the flame of all things F & S (and reportedly writing a biography of Michael Flanders) gives detailed notes on the "Hat Trick" compilation. The following quote is Leon Berger's, from the booklet of notes.

"A brief lesson in the low-tech phoneboxes then owned by the General Post Office (GPO). To make a call, you inserted your coins, dialled, and on hearing a reply, you had a few seconds in which to press Button A to be connected and your money was swallowed. If the recipient failed to identify themselves speedily, you risked losing your cash. Hence, printed in the front of every Telephone Directory was the instruction:
'Say who you are. Do not just say "Hullo" .'

--page xv, Hat-Tracks (guide to the songs)
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