My daughter has been explaining musical composition, which she knows much more about than I do, to me. At one point in the conversation, trying to make sense of the idea of a line of music, I suggested that her harp could only play one; she pointed out that it could manage two. Which put into my mind a cartoon—something I am entirely incapable of producing, given a complete lack of artistic talent.
The caption is "What do you mean you can't play eight lines on a harp?" The picture shows a harp--being played by an octopus.