The deadly irony of gunpowder - Eric Rosado

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In the mid-ninth century, Chinese chemists, hard at work on an immortality potion, instead invented gunpowder. They soon found that this highly inflammable powder was far from an elixir of life -- they put it to use in bombs against Mongol invaders, and the rest was history. Eric Rosado details how gunpowder has caused devastation around the world, despite the incandescent beauty of fireworks.

Lesson by Eric Rosado, animation by Zedem Media.

Everybody loves fireworks --

the lights, the colors,

and, of course, the big boom.

But the history of fireworks

isn't all hugs and celebrations.

Long before epic fireworks displays,

chemists in China invented the key ingredient

that propels those bright lights into the sky.

That invention was what we now call gunpowder.

Our story begins back in ancient China

in the mid-ninth century

where early Chinese alchemists

were trying to create a potion for immortality.

Instead, what they created was a flammable powder

that burned down many of their homes.

They quickly realized that this black powder,

which they called fire medicine,

was precisely the opposite of something

that would make you live forever.

In these early days,

the Chinese hadn't yet figured out

how to make the powder explode;

it was simply very flammable,

and their armies used it

to make flaming arrows

and even a flamethrower.

But once they figured out the right proportions

of ingredients to create a blast,

they began using the powder even more,

creating fireworks to keep evil spirits away

and bombs to defend themselves

against Mongol invaders.

It was these Mongols, most likely,

who spread the invention of gunpowder

across the world.

After fielding Chinese attacks,

they learned how to produce the powder themselves

and brought it with them

on their conquests in Persia and India.

William of Rubruck,

a European ambassador to the Mongols,

was likely responsible for bringing gunpowder

back to Europe around 1254.

From there, engineers and military inventors

created all kinds of destructive weapons.

From bombs to guns to cannons,

gunpowder left its mark on the world

in some pretty terrible ways,

in contrast to the beautiful marks

it can leave in the air.

So, how does black powder propel

fireworks into the sky?

You might have seen old Westerns or cartoons

where a trail of gunpowder is lit

and it leads to a large and obviously explosive barrel.

Once the fire gets to the barrel,

a large boom occurs.

But why doesn't the trail itself explode?

The reason is that burning the powder

releases energy and gases.

While the trail is burning,

these are easily released into the surrounding air.

But when the gunpowder

is contained within the barrel,

the energy and gases cannot easily escape

and build up until

BOOM!

Firework canisters provide

a single, upward-facing outlet

to channel this explosive energy.

The wick ignites the gunpowder

and the energy takes

the easiest exit from the canister,

launching the firework high into the sky.

The flame then makes its way

through the firework's encasing

and the same reaction occurs

high above our heads.

So, while the Chinese alchemists

never found the compound for eternal life,

they did find something

that would go on to shape all of civilization,

something that has caused

many tragic moments in human history,

and yet still gives us hope

when we look up in celebration

at the colorful night sky.