Forget hoverboards, where the hell are our futuristic breast-washing machines?S

Pictured here: an ad for a metallic-looking, retro-futuristic "breast washer," circa 1930s, that could easily have been a prop on the set of Fritz Lang's Metropolis.

Our questions: did these actually exist? Do they still exist? If so, why do we never see them? How do they work? What are the benefits (real or imagined) of breast-washing with a breast-washer as opposed to self-washing one's own breasts? Inquiring minds want to know.

[Retronaut via boingboing]