What are we looking at?

I took a pause to notice this picture again after I got tired of listening to the few contemporary artists I put up with nowadays and decided to go back to never fail great music. Fleetwood Mac is one of my all-time favorite bands, but I had not really examined this album cover from 1977. What really stuck out to me, now, and what I perhaps didn’t notice before, was the pair of balls just hanging there between Mick Fleetwood's legs; his stance – hand akimbo, with that look on his face as he holds out, a crystal ball, with a distorted image, to the delicate looking Stevie Nicks, who gazes at it, while perching one leg over his balleted, stooled foot. Huh? After doing a little research I discovered that this picture is representational of some sort of old-fashioned courtship. However, I could not get past the balls. I mean, really. What is that supposed to mean? Is it symbolic is his manhood, or his power over her? Once I took notice of those balls, noting else in this picture mattered. Am I perhaps looking at the end of my love affair with Fleetwood Mac? Now, I have to go back and really listen to every song on this album, that I have been singing along to and making memories with for over a decade.