A man lying beneath a shower head (the thing I thought was a toilet plunger) with his feet over his head/ The words: Shower lower abdomen and thighs, pelvic region for a long time. Turn over and shower all of back from neck to heels thoughly, also sides, then raise legs and let shower strike over rectum, lower back, groins and inside the legs.
Yes, it says groins not groin.
It’s me, what’s the book?
Google seems to think it’s from The Fountain of Youth, or Curing by Water by Benedict Lust, published in 1923.