Skills

Operating An Agitator Washing Machine And Clothes Ringer

FieldDomestic duties
Went Obsolete1980s perhaps
Made Obsolete ByInternal spin cycle
Knowledge Assumed 
When useful 

Using the old agitator washing machines required many skills. But the most important skill was in the feeding of wet clothes through the attached wringer. They had to be fed through the two rollers in a steady and careful fashion. Too many at once, and the wringer would pop its top. Casual care and your fingers might find themselves being drawn in (a nightmare thought for kids especially). And when the top popped, it made a very quick, horrendous and loud sound.

I'm surprised Stephen King didn't write a short story on the perils of operating these beasts.

I'd add "spelling" as an obsolete skill, as the title of this topic obviously reveals.