A few nice simple bathroom images I found:
Capitol Place Shower Instructions
Image by ATIS547
Hilton Garden Inn Capitol Place Hotel, in Austin Texas, has the world’s most difficult to operate shower controls — they appear deceptively simple, but require this warning because when guests try the obvious affordance of turning the knob, the handle breaks.
Here is the actual shower control: www.flickr.com/photos/albaum/422521532/
Photographed May 18, 2006.
"Shower Controls — Do Not Twist Knob! Push Left or Right for Temperature Control"