I came across a book years ago that sought to prove subliminal messages in advertising, music, and art. There was a section dedicated to "demonism" in rock. The author took aim at the black object seen on PRESENCE's album cover. According to this author, the black image represented the black prince and was featured in the background of other Zeppelin albums. I'm sure Jimmy and the boys smiled at the royalty checks when they found out more albums were sold because of this very important uncovered "truth".
Yeah, the black object represents the black prince. And here I thought the family just discovered an unmentionable source of amusement for one of the family members.
And, to play these bad albums, we can't forget...