Herbert Henry Dow

Dow was a chemist who knew that the brine under Midland, Michigan was rich in bromine, which photographers and drug makers needed, and he developed an electrolytic way to extract it. Early backers lost patience and his first companies failed, but Dow Chemical, founded in 1897, made the process pay. When a German cartel dumped cheap bromine in the US to crush him, he quietly bought it up and resold it in Europe, which is about as practical a use of specialist knowledge as business offers.