Serendipity is the accidental discovery of something useful whilst looking for something else. And this is exactly what happened to a 17th century German while experimenting with urine.

Hennig Brandt was an unsuccessful businessman and former soldier from Hamburg who was determined to discover the Philosopher's Stone.

The Philosopher's Stone was based on the studies of the 8th century Iranian alchemist Abu Musa Jabir ibn Hayyan (known in short as Geber). Geber who also studied philosophy, astronomy and physics thought it might be possible to rearrange the properties of one common metal to form gold.

Geber believed all that was required was a  potion or material  which contained the al-iksir ( elixir) which would transform ordinary stones into gold. He used the idea that elements  were made of four qualities: heat, coldness, dryness and moisture.

Geber's ideas had popular appeal and seemed to be based on reasonable science. Thus alchemy was born and with it the quest to find the mythical ingredient which would make a person rich.

It was certainly an idea which was attractive to the bankrupt Hennig Brandt in Hamburg.

Brandt had heard rumours that it might be possible to use urine to turn silver or lead into gold.

So in 1669 Brandt decided to fully investigate the idea using a very large amount of urine. He collected buckets and buckets of urine. Some reports say he used 40 buckets, others say he collected 50 buckets. What ever, it was a lot. He was utterly determined to find the Philosopher's Stone.

The poor Hamburg alchemist let the buckets of urine putrify then gather maggots. Eventually the urine turned into a pasty glue and white marks appeared on the laboratory walls.

Then one evening Brandt noticed his workroom was glowing. He went and investigated and found the walls and the paste in the buckets were shining with a strange white green light.

Brandt named his discovery phosphorous, which meant light bringing.

Phosphorous was further developed by other chemists. It is now used in explosives, lamps, china crockery, cleaning powders, detergents,  pesticides and a host of other products.

Unfortunately it did not make Brandt wealthy....