We breathe mostly nitrogen. It makes up about 80% of the air. It doesn’t hurt us and it doesn’t help us — it’s like those free airplane mints.
Air’s second largest component is oxygen. Our atmosphere started out with essentially none of it, but it grew increasingly prevalent during the “Great Oxidation Event” 2.4 billion years ago. That was caused by our planet’s growing plant population, which helps explain why no other planet we’ve yet discovered has any free oxygen. You need life, we think, in order to have gaseous oxygen floating around. Oxygen comprises about a fifth of the atmosphere. Taken together with nitrogen, that leaves about one percent of the air unaccounted for.
So what is that one percent? What’s the third most common element that you inhale with each and every breath?
Take a guess! It’s one of the signs of how futile was our science educations that most of us cannot remember how many chambers our hearts contain, the latitude of the equator or the ingredients of air.
Most would guess carbon dioxide, which actually makes up less than one twentieth of one percent, greenhouse infamy notwithstanding. Anyway, to name that third-most-common gas we breathe, few would choose the element discovered barely over a century ago: Argon.
Argon is the gas inside the round, hot light bulbs that used to be everywhere, so we looked at it a lot even though we rarely thought about it. Argon doesn’t even help us think, unlike hydrogen and oxygen, the majority stuff Nature uses to construct our brains.
Argon was discovered by a Scot, William Ramsay, who eventually won the Nobel prize for his work with gases. He also discovered the universe’s second most common substance, helium, as well as neon, krypton and xenon. He even sent electricity through neon/argon mixtures to produce the brilliant orange tube lights that now blaze along the world’s commercial streets with single words such as “open.”
They’re called neon lights, but only the orange and red ones commonly contain neon. Almost every other color has argon gas, usually mixed with a little vaporized mercury, with the hue mainly created by the color of the glass. Having a commercial neon sign in your home is a decorative style that was once “in” but is presently controversial in fashion circles. You can find cool used signs in some antique shops or even on Amazon. But be sure you don’t get the modern, now-common LED signage, which doesn’t exude the same feeling, glaring though it may be.
Anyway, Ramsay found argon around the time my late grandmother was born, barely over a hundred years ago. Who’s heard of him today? You’d think someone who’d uncovered five of the universe’s 92 elements, more than anyone else, including the third commonest substance we breathe, would be remembered alongside his contemporaries like Thomas Edison.
The air exhaled by Ramsey on his last breath in 1912 has long mixed evenly with the atmosphere. By the time eight years had passed, his final breath had blended so thoroughly around the world that even today you take in at least one molecule of Ramsay’s breath with every inhalation.
Seems somehow unsanitary, but it does connect us all.
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