Nitrogen

Nitrogen was isolated in 1772 by the Scottish physician Daniel Rutherford, who called it noxious or mephitic air because it neither supported life nor combustion; Carl Wilhelm Scheele and Henry Cavendish reached it independently. The modern name was coined by Jean-Antoine Chaptal in 1790 as nitrogene, meaning niter-former, from niter, the old name for saltpetre (potassium nitrate).

Antoine Lavoisier preferred azote, from the Greek for lifeless, a name that survives in French and in words like azide. Nitrogen makes up about seventy-eight per cent of the atmosphere yet is chemically aloof. Cooled to a liquid it makes a cheap and widely used refrigerant, while its compounds, from ammonia and nitrate fertilisers to explosives, rank among the most important of industrial chemicals; nitrogen is also a building block of every protein and strand of DNA. The industrial capture of atmospheric nitrogen transformed human history: the Haber-Bosch process, developed by Fritz Haber and Carl Bosch between 1909 and 1913, fixes nitrogen from the air into ammonia for fertiliser, a feat sometimes called making bread from air, and it is credited with sustaining a large share of the world's population growth since. The same chemistry that feeds billions also underlies high explosives, since nitrate compounds are the active ingredient of gunpowder, dynamite and TNT alike, so nitrogen's industrial harnessing carries both a Nobel Prize for Haber and a lasting association with the machinery of war.

Nitrogen's near-namesake in the esoteric literature is azoth, a central term of alchemy denoting the universal solvent, the animating mercurial principle, or the first matter of the Work. The resemblance to azote is a coincidence of sound: azoth descends from the Arabic al-zauq, quicksilver, and was reinforced by a play on the first and last letters of several alphabets, whereas azote was deliberately built from Greek roots to mean lifeless. The two should not be run together, though later writers sometimes did. Nitrogen's genuine pre-modern presence lies in saltpetre, the essential oxidiser of gunpowder, whose manufacture and near-magical potency shaped warfare and, indirectly, the chemistry that would later name the element.

In Paracelsian alchemy azoth became almost a proper name: Paracelsus used it both for the alchemical prima materia and, more idiosyncratically, for a supposed universal remedy he claimed to carry always at his side, sometimes said to be sealed in the pommel of his sword. The word's supposed derivation from the first and last letters of the Latin, Greek and Hebrew alphabets (A and Z, alpha and omega, aleph and tau) reflects the alchemical habit of building words that gestured at cosmic totality, everything from beginning to end. Nitrogen the gas, discovered and named on purely rational chemical grounds nearly two centuries later, shares nothing with this tradition beyond an accidental echo of sound.