"What's the purpose of the beads in body washes - a scrubbing agent, or is it for scratching when you don't want to scratch?"

They are for exfoliation, Joe. Human skin is continually flaking off and renewing itself. The theory is that if you can abrade away the skin which has already exfoliated or about to, then you reveal the newer, softer skin underneath. And, of course, the dirt comes off with the exfoliated cells.

There was a fascinating series of programmes, on British TV recently, about life in Tudor England. In those days people tended not to wash because water was scarce and and accumulating enough for normal household chores was very labour intensive. Many people just rubbed themselves down with a rough towel - hence, presumably, exfoliating and removing (most of) the dirt at the same time. There's an old joke about Elizabeth I of England, "bathing once a year, whether she needed to or not!" As the presenter of the programmes pointed out, Elizabethans wouldn't have got the joke!

Still, I'm glad that I don't live in Tudor England!