Jennings' "Pedestal Vase" won the Gold Medal Award at the Health Exhibition of 1884, being judged "as perfect a sanitary closet as can be made". In a test it completely cleared with a 2-gallon flush

10 apples averaging 1 1/4 inches diameter
1 flat sponge about 4 1/2 inches diameter
Plumbers "smudge" coated over the pan
4 pieces of paper adhering closely to the soiled surface.

A simpler test was that improvised by Mr Shanks who, when trying a new model, seized the cap from the head of an attendant apprentice, thrust it in, pulled the chain, saw it go, and cried out happily, "It works!"

That comes from a book called "Clean and Decent - the fascinating hostory of the Bathroom and the WC" by Lawrence Wright, published originally in 1960. (Ah, the swinging sixties...) No bog library is complete without this master work of social history.