Who Discovered Potassium?
Potassium was discovered in 1807 by Humphry Davy, a young British man working as an apprentice to a surgeon-apothecary. He became interested in the science of passing electrical current through various substances to break them apart, a pratice that would later become known as electrolysis.
Davy was in fact made a public lecturer at the Royal Institution in London long before his potassium discoveries, in 1801. Six years later, he began his electrolysis odyssey with two simple but successful experiments: the separation of potassium from molten potash, and the extraction of sodium from common salt.
Later on, he used the properties of potassium for other experiments. He relied on the metal's reduction power to create boron and also perfected a way to separate it from sodium. Davy's London lectures became increasingly popular, and as the scientist wrote about his discoveries and published an agricultural-themed book, his fame grew. He even at one point received a commendation from the French emperor Napoleon.
An Assist from Volta
Another area where Davy was a pioneer was the realm of nitrous oxide, or laughing gas. In 1799, he made the bold suggestion that it could be used as a local anesthetic, but his recommendations were ignored. Part of the problem was that at the time, laughing gas was commonly used as a social drug.
Davy's meteoric rise in the field of electrochemistry would not have been possible without the invention in 1800 of the electric pile by Italian physicist Alessandro Volta. Without him, and the advances of many others, all the compounds and elements isolated by Davy in later years would have been much harder if not impossible to deduce.
Today, one of the prevalent uses of potassium is in agriculture fertilizers. Even there, Davy was a true pioneer, writing the first text on the application of the "K" element metal to agriculture. He was knighted in 1812 and served as President of the Royal Society from 1820 until 1827.