The discovery of phosphorus, 50 years after this statue was erected, involved a lot of urine. (Photo: Wikimedia Commons)
Hennig Brand was an alchemist on a mission: transmute urine into gold. In the 17th century, he gathered about a thousand gallons of pee and boiled it down to separate out a substance that he believed would give him gold.
Obviously, if he had succeeded, we all would know about it. But what he did find was white phosphorus, which self-ignites in the air. He called it cold fire. Today we use it in explosives, fireworks, and fertilizers — and that red strip on the side of matchboxes is just red phosphorus waiting to react to the sulfur on the match head.