My first boyfriend taught me this in Edinburgh in 1968. I thought he was wonderful, but he had to explain several of the verses. He always sang the chorus, and narrated the verses in a pseudo-American accent. He also taught me a thing about a man who had "large balls, twice as heavy as lead" who apparently, "with a singular twist of his muscular wrist, he threw them over his head " (tarara boom etc.) Does anyone know that one? I was only seventeen and completely innocent and naive. I smile now, I was horrified and fascinated in equal measure! He is now Professor of Epidemiology in Scotland, I don't suppose he sings this song any more!!