So if this really works, how come it wasn't noticed before???
I can see it now in this old 1930's black and white movie....
A rusty tramp steamer is at sea in the Atlantic ..
The watch is smoking, takes a last draw, drops the butt, and grinds it out with his foot to make a black mark on the deck.
He notices that there are other blackened circular splotches on the rusty deck and they have NO RUST.......
When he gets to port, he immediately patents Butt Paint, the paint that stops rust dead.....