Davy, Humphry (1778–1829)

A portrait of the English chemist Humphry Davy, c. 1810. Best known for his pioneering experiments in electrochemistry and for his invention of the miner's safety lamp, called the Davy lamp, he also discovered the anaesthetic properties of laughing gas.

English chemist. He discovered, by electrolysis, the metallic elements sodium and potassium in 1807, and calcium, boron, magnesium, strontium, and barium in 1808. In addition, he established that chlorine is an element and proposed that hydrogen is present in all acids. He invented the safety lamp for use in mines where methane was present, enabling miners to work in previously unsafe conditions. He was knighted for his work in 1812 and made baronet in 1818.

Davy's experiments on electrolysis of aqueous (water-based) solutions from 1800 led him to suggest its large-scale use in the alkali industry. He proposed the theory that the mechanism of electrolysis could be explained in terms of substances that have opposite electric charges, which could be arranged on a scale of relative affinities – the foundation of the modern electrochemical series. His study of the alkali metals provided proof of French chemist Antoine Lavoisier's idea that all alkalis contain oxygen.

Davy was born in Penzance, Cornwall. He was apprenticed to an apothecary, where he learned how to prepare medical treatments based on the combining of chemicals and plants. As a laboratory assistant in Bristol in 1799, he discovered the respiratory effects of laughing gas (nitrous oxide). He moved to the Royal Institution, London 1801. In 1813 he took on Michael Faraday as a laboratory assistant.

Davy introduced a chemical approach to agriculture, the tanning industry, and mineralogy; he designed an arc lamp for illumination and an electrolytic process for the desalination of sea water to make it drinkable. He was elected president of the Royal Society in 1820.