Ever wondered where the practice of pouring vegetable oil down the toilet to lubricate the pump originated? All the early manual toilets had leather seals, gaskets etc, which--because leather asbsorbs oil-- were kept lubricated by flushing a tablespoon or two of oil (typically linseed oil) when the toilet could sit for at least a few hours. It lasted for months. Today, the only thing that can last longer than a few flushes in a toilet pump full of rubber and neoprene is thick teflon or silicon grease, which also lasts for months. But even though oil just washes out in a few flushes, people still insist on pouring it down the toilet--vegetable oil mostly because it's readily available and cheap--when it would actually be easier and cheaper to learn how to squirt a little grease into the pump once or twice a year.
--Peggie
"If you can't explain it to a six year old, you don't completely understand it yourself." --Albert Einstein