Armies have been attacking each other with gases
as far back as ancient Greece.
But the chemicals available way back then were
much less effective than, say, pouring boiling oil on someone.
All that changed, however, with the development
of deadly new gases during World War One.
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Before World War One, all the major
European powers signed a pact promising not to put
poison gas in projectiles and fire them at each other.
But as the supposedly short war dragged on, both
sides started experimenting with poisonous
gases - bromine was an early example.
Like other halogens, bromine has seven electrons
in its outer energy level, but it desperately wants eight.
So in theory bromine would shred cells in the eyes and nose to steal electrons, like
a super-powered tear gas.
It sounds like a powerful weapon, but most
of these bromine-gas attacks failed.
When the Germans attacked the Russians,
For instance, the freezing Russian winter
meant the gas couldn’t vaporize in the air.
And however irritating, bromine rarely incapacitated soldiers.
Overall, troops didn’t even realize they’d been “attacked” in most cases.
All that began to change when a bald,
mustachioed, German chemist named Fritz Haber entered the scene.
Haber is best remembered for figuring out
how to convert nitrogen in the air to
ammonia, a precursor for fertilizer.
Billions of people around the world today
depend on this chemical reaction for food,
and he won a Nobel prize for it.
But Haber was willing to pervert his chemical genius
to help Germany win the war, and he set out
to craft deadlier chemical weapons, leading
a group of scientists the German military
ghoulishly called the Disinfection Unit.
He decided to ditch bromine and focus on chlorine.
Chlorine sits above bromine on the periodic table
and is more aggressive about attacking cells for electrons.
If bromine is a soldier on horseback, chlorine
is an armored tank.
Chlorine was so powerful, in fact, that Haber believed
it would break the trench warfare stalemate across
Europe and win the war immediately.
Haber actually directed the first chlorine attack
in person, at Ypres in modern Belgium.
It began on April 22, 1915, as soon as the winds
shifted in Germany’s favor. Specially trained
troops crept forward in the trenches and turned
the valves on 5,730 canisters of chlorine gas.
A green cloud fifty feet high and four miles
long rolled toward the French lines.
When chlorine hits the mouth and throat, it
induces a reflex to hold your breath.
Eventually you gasp, and the chlorine reacts
with water inside cells to make acids.
These acids tear open the capillaries and air
sacs in the lungs, spilling out fluids that collect
in pools and prevent the lungs from inhaling oxygen.
Victims of chlorine attacks actually drown on dry land.
Although estimates vary, several thousand
men probably succumbed that day in Ypres.
And what did Germany gain from the first successful gas attack in history?
Nothing.
German generals didn’t think the attack
would work, so they didn’t have enough
troops ready to occupy the enemy’s trenches.
They gained very little ground.
Chemists on both sides invented several other
chlorine-based gases, including the truly
nasty phosgene, and mustard gas.
But strategically, gas attacks accomplished little.
Both sides began to manufacture gas masks
in huge numbers; in a pinch, soldiers could also
urinate on their handkerchiefs and hold
them over their noses for protection.
Millions of men did suffer lung damage, and
millions more lived in terror of gas—but all that
suffering still couldn’t break the trench stalemate.
Gas warfare also destroyed Fritz Haber’s personal life.
His wife Clara shot herself in part because of his work on gas.
And although Haber won the Nobel Prize in 1918
for his ammonia-fertilizer work, he was also
condemned as a war criminal by the larger scientific community.
Even worse, his beloved homeland betrayed him.
When the Nazis took over Germany in the 1930s,
they persecuted Jews like Haber.
He died in exile in 1934.
Gases continued to haunt Haber’s legacy.
Early in his career, some under Haber’s watch
were working with an insecticide called Zyklon.
Just before World War Two, a German company
tinkered with the formula to produce
a second generation of the gas.
This became known as Zyklon B, and concentration
camps used it to gas millions of Jewish
prisoners—including Haber’s relatives.
In the century since World War One, gas attacks
have lost none of their power to terrify us.
Why?
Because they creep in silently, on the wind.
Because they turn the very air we breathe into a weapon.
In fact, gas has always been a psychological weapon
Than a physical one. But gases have
killed far fewer people in history than bullets,
they retain a horror unmatched by almost any other weapon.
Thanks for watching everyone.
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coverage of the 100th anniversary of chemical weapons.
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