The origin of the word gas: the alchemist and chaos

Almost every word in a language was invented by no one: they took shape on their own, mouth to mouth, over centuries. The word gas is a very rare exception. We know exactly who created it, when, and where it came from: a Flemish physician and alchemist of the seventeenth century who, looking for a name for an invisible substance that kept escaping from his experiments, reached for an old Greek word for chaos. Few everyday words have such a precise birth certificate.

The man who needed a new word

The inventor was Jan Baptist van Helmont (Brussels, 1579–1644), a physician, chemist and alchemist of the kind who still lived with one foot in magic and the other in modern science. Studying what happened when he burned charcoal or fermented the must of wine, he realized something no one had stated clearly before: that those «airs» given off were not all the same air. There were vapors different from one another and different from the air we breathe.

The problem was that no word existed to name them. In his day people spoke of «spirits», «vapors» or «exhalations», vague terms inherited from alchemy. Van Helmont, regarded today as the founder of the chemistry of gases (so-called pneumatic chemistry), understood that a new term was needed for a new category of matter. And he decided to make one himself.

A word drawn from chaos

The matter he studied had no shape of its own: it expanded to fill any container, with no order or outline. That reminded Van Helmont of a very ancient idea, the Greek chaos (χάος), which in mythology did not mean «disorder» as it does today, but the formless, primordial void that existed before the world had shape. That boundless emptiness was the perfect image for something that was neither solid nor liquid and that occupied all available space.

Here comes a delightful linguistic detail. In Dutch, Van Helmont's language, the letter «g» does not sound as it does in English, but like a harsh, throaty sound very close to the ch (the letter chi, χ) of Greek. So when Van Helmont wrote gas, he was in fact transcribing almost letter for letter how chaos sounded in his mouth. «Gas» is nothing but «chaos» pronounced the Flemish way. He said as much himself: «this vapor I call gas, not far from the chaos of the ancients».

The shadow of Paracelsus

Van Helmont did not pull the idea from nowhere. A century earlier, the Swiss physician and alchemist Paracelsus had already used the word «chaos» to refer to air and to the invisible media from which living beings draw their nourishment. Van Helmont, a keen reader of his, took up that intuition and turned it into a precise technical term. It is the same Paracelsus who appears in the story of the word «alcohol», when the alchemists began to use that name for the purest essence distilled from wine: two chemical words that came out of the same Renaissance workshop.

The first gas Van Helmont identified and named was the one he called gas sylvestre («gas of the woods» or «wild gas»): the vapor that comes off charcoal as it burns, off wine as it ferments, and from the bottom of certain caves where the air becomes unbreathable. Today we know that this gas sylvestre was carbon dioxide, the same CO₂ of the bubbles in a soda and of our own breathing.

The twin word no one remembers

Van Helmont, thrilled with inventing vocabulary, created another word, sister to «gas»: blas, with which he meant to name a kind of vital force or motion that governed matter and the stars. But blas did not have behind it a reality as concrete and useful as the vapors, and it never caught on: today no one uses it or remembers it. The fate of the two words could not have been more different. «Gas» triumphed because it named something science urgently needed to name; «blas» faded like a passing fashion.

The word «gas» did take its time to prevail. Van Helmont used it in his writings, published mostly posthumously in his Ortus medicinae (1648), but more than a century passed before eighteenth-century chemistry —that of Lavoisier and the great discoverers of the airs— adopted it for good. Once it did, «gas» never let go of language: it passed from Dutch to French, to English and to Spanish almost without changing a letter.

The chaos we breathe

Today «gas» is one of the most neutral and technical words there are: the gas of the stove, the gas in a balloon, greenhouse gases. It is hard to imagine that it was born from an image as poetic as the primordial void of Greek myth. But every time we turn on the stove or inflate a tire we are, without knowing it, invoking the chaos of the ancients, that formless nothingness which an alchemist from Brussels decided, four centuries ago, to shut inside three letters. It is, alongside «cipher» and «zero» or the history of lithium, another example of how science leaves its mark on the words we use without thinking.

References

1. «Gas — Etymology, Origin & Meaning», Etymonline. etymonline.com
2. «Jan Baptist van Helmont», Wikipedia. en.wikipedia.org
3. «gas, n.¹ & adj. — etymology», Oxford English Dictionary. oed.com
4. «Joan Baptista van Helmont», Linda Hall Library — Scientist of the Day. lindahall.org

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