Original subtitles

- [Narrator] The world's greatest structures,

pushed the boundaries of engineering,

all fueled by a constant desire to innovate.

- Without engineering,

there would be no modern world.

- [Narrator] Gigantic buildings,

complex infrastructure, and ingenious inventions,

- Engineering is the key

that turns dreams into reality.

- [Narrator] Many of today's incredible achievements

rely on breakthrough technologies

first devised by ancient engineers.

- It's astounding how they achieved this.

- [Narrator] Early civilizations

built on an unimaginable scale

and with incredible precision.

- They raised a bar for engineering

in a way that no one thought possible.

- These are some of the finest engineers in history.

- [Narrator] Redefining the known laws of physics

and dreaming up the impossible,

they constructed engineering wonders

from colossal stadiums to mighty waterways

and complex machines,

all with the simplest of tools.

- You cannot imagine the skills

people would've needed to build like this.

- [Narrator] By unearthing the mysteries

left by these ancient engineers,

we can now decode their secrets.

- That so many of their creations still survive

is testament to their engineering prowess.

- [Narrator] And ultimately reveal how they're genius

laid the foundations for everything we build today.

(grand, triumphant music playing)

(army screaming into attack)

From the earliest times,

human history has been driven by the use

of a ranged weapons,

brilliant yet brutal engineering achievements

behind the rise and fall of some

of the world's greatest ancient civilizations.

- Human beings are

wonderful and inventive and curious,

but they're also a violent and nasty and greedy.

And there's a streak of human nature that wants to compete

and competing leads to conflict

and conflict leads to weaponry.

- We're humans and it's part of who we are.

It's embedded in our DNA. We're pretty violent creatures.

And we always find new ways of harming those

and taking the things that we love; terrible, but true.

- [Narrator] Times of war

have witnessed violence and suffering

on an unimaginable scale,

but also steered major advances

in science, technology, and engineering.

- Weapons also act as an in initiator for innovation.

They tend to advance what is possible

in terms of technology,

which can then seep into other areas of industry

and benefit mankind in plenty of other ways.

- [Narrator] While the very first ranged weapons

were used op close,

usually within a stone's throw,

the battle distance has continued to grow,

as ancient engineers

developed more efficient and destructive weaponry.

- Over the millennia,

humans have used engineering and material science

to improve precision, power,

and mobility of projectile weapons.

- It's an inescapable truth

that whoever has the best weapon,

the most advanced weapon, has a greater chance of winning.

- [Narrator] Today,

wars continue to be fought on huge battlefields.

Across the sea, and in the air,

and despite the inescapable death and destruction caused,

the need for new and improved weapons

shows no sign of stopping.

- We're always improving weapons

and whichever way you look at it, weapons is a big business.

There's a huge amount of money pumped into defense.

- [Narrator] In 2020, the global military expenditure

rose to almost $2 trillion,

with the USA recognized

as the world's largest military spender,

investing more than $775 billion

in that year alone.

But none of this military technology would've existed

without the very first tools,

more than two and a half million years ago.

Long before Neanderthals or modern humans roamed the earth,

an ancient species of human

began to pick up items around them.

- Life would've been astonishingly difficult

in the Stone Age, and humans learned very quickly

that they wouldn't survive with just their bare hands.

- [Narrator] By splitting pebbles,

they created primitive stone tools

marking the beginning of the Stone Age,

that covered the greatest portion of human history,

until around 3,300 BC.

- Tools are amazing inventions

because they give the population an evolutionary advantage.

So it means that they can outperform their rivals,

they can control more territory,

they can get access to more resources, et cetera.

So the invention of tools, when it happened,

was an absolutely seminal moment,

as seminal as the invention of fire.

- [Narrator] These early humans

gradually developed meat-rich diets as scavengers,

before embracing the hunter-gatherer lifestyle

2 million years ago,

relying on large branches and heavy rocks

to bring down prey.

- From the moment at which we are hunter-gatherers,

we're using sticks and stones both to capture animals,

but also to gather crops.

- [Narrator] But humans eventually

turned their attention to larger and more dangerous animals

and that called for a new piece in their arsenal.

By sharpening a wooden pole at one end

with a rock or piece of bone,

they produced one of the earliest weapons

devised by humans, 500,000 years ago:

the spear.

- Well, an early spear is a straight stick,

full staff, a utilitarian tool,

which you can use for a variety of things

for a stick with a sharp end,

that can be a weapon for use for anything.

- [Narrator] Originally used as a thrusting weapon

to keep the hunters out of harm's way,

but it wasn't fool-proof.

- You tend to find on the bones and skeletons

of very early humans, huge physical injuries

because of the fact that they put themselves at risk

by being so close to their prey or their opponents,

'cause they would've used the spear

to stick into something; to stab something.

- [Narrator] Early humans then began to throw the spear

to hunt at a greater distance.

- The spear is really genius

in its simplicity of how it works.

So before ancient humans will have understood

anything around aerodynamics,

they built these incredible weapons

that were so sleek and slender

that they would travel through the air

with very little air resistance

and hit a target very precisely.

- [Narrator] An effective weapon for killing large animals,

such as mammoths and bison,

which were an essential part of their diet.

- For really big game, it's absolutely ideal

where multiple projectiles can hit the animal

and bring down something as big as a mammoth,

which we've actually seen in the archeological record.

- [Narrator] And with the help of fire,

charring was used to harden and sharpen the spear tip.

- Charring actually changes

the chemical composition of the wood at the point,

making it stronger, also more brittle,

but the strength of it is important

for being able to go into the target.

- [Narrator] The flames fuse the grains of the timber,

even tighter together, resulting in a stronger,

more durable, piece of wood.

And that wasn't the only way the spear was improved further.

Humans also realized that a pointed stone

could be attached to the end of a spear

increasing its sharpness,

and thus increasing the damage done

when it reached the target.

- There's a real lesson to learn here,

when we're talking about

all these various stages of the evolution of weaponry,

and that is that we should never, ever,

underestimate peoples of the past.

- [Narrator] A simple but successful hunting weapon:

light, lethal, and relatively easy to construct.

But the distance reached by a spear

was limited by the strength of the thrower.

- How to extend the range accurately

of the human beings using their wits and their ingenuity

to give themselves this advantage

over the other apex predators.

- [Narrator] Paleolithic humans found a way

to throw further and with more force than ever before

with an ingenious device known as an atlatl.

- An atlatl is one of the earliest ancient weapons

that is more than just human power.

It was a curved piece of wood.

And at one end you would be able to slot a spear into it

and you could essentially stretch your arm up

and fling the spear forward

with much greater force and acceleration

than just using your own arm.

- The atlatl a very clever invention.

It creates another hinge, almost like another elbow

and that extends the length of your throwing arm

and that means you can throw the spear much, much further.

- [Narrator] As the hunter swings the atlatl forward,

similar to an overhand tennis serve,

the force is concentrated

at the point where the hooks connects to the spear.

Reaching speeds of around 78 miles per hour,

spears can now be projected up to 330 feet

with enough force to kill a woolly mammoth.

- It took the human input and basically magnified it.

By designing weapons and using engineering,

you could start to minimize the human energy,

the human endeavor part of it.

- What we are seeing here, effectively,

is the very earliest evidence of engineering.

Somebody invented the lever.

- [Narrator] The proper use of the atlatl

made spear-assisted hunting

an efficient and deadly operation.

- There's far more to an atlatl

than some people may initially realize.

If it's too long, it's inefficient.

If it's too short, then you're not getting

all the power out of it that you should do.

It's a case of making something,

many times fine-tuning it,

seeing what works and trying to replicate that.

- [Narrator] One of humankind's first mechanical inventions,

but over the millennia,

the species continued to spread across the planet.

- Initially the weapons are just used for hunting,

but of course, if you're successful at hunting,

the population grows.

That will inevitably lead to conflict

as people are competing for resources.

- [Narrator] Numbers increased,

space became more limited, and tensions grew.

The groups of people began waging war against each other,

making use of the weapons

that had proven so successful in hunting.

But they discovered that a throwing spear

carried a decisive risk in battle.

- Spears are good 'cause they give you range.

You can throw them without closing on the enemy

so you are safe as you throw it.

But of course, if you miss,

they can pick it up and throw it back.

- [Narrator] Although other ranged weapons

were invented throughout ancient history,

the throwing spear remained an important armament

for the Egyptians, Greeks and other civilizations,

constantly improved and arguably perfected

by one of history's most legendary military forces.

The Romans: true masters of war and weaponry.

- I would argue that the Roman legionary

of any phase of their existence

was the elite warrior of the ancient world.

- Rome's prowess through its heavy infantry, its legion,

is their organized, disciplined, standing army.

It's the best army in the ancient world.

It is the foundation of the Roman empire

and it stood the source of their power and wealth.

- [Narrator] Hundreds of thousands of Roman soldiers,

each equipped with carefully engineered weapons of war,

including one piece that marked the beginning

of a new chapter in the history of spears.

- If you were to look at the classic Roman legionnaire,

the weapon which most people would physically recognize

is the pilum.

- The Roman pilum is a throwing spear.

Spear carrying infantry have a very,

very long history in the Roman world.

But what the Romans do is refine, both the equipment

and I think also crucially the tactics.

- [Narrator] It was the decisive weapon

for Imperial legions, used in battles for centuries.

- You have a wooden shaft and then you have a socket,

and in the socket goes an iron tang,

and on the end of the tang there's a barbed head.

Now the tank is quite thin. That's important.

And also the socket's got a lead weight.

- [Narrator] An unusual design

that was perfect against Rome's enemies,

the barbarian hoards,

armed to the teeth and carrying heavy shields.

And that's where the pilum comes in.

- The heavy pilum disrupts the opponents as they come in

because of this amazing engineering example

from the world of weaponry.

- [Narrator] Ancient records describe how the pilum

was able to punch through their adversaries shields.

The broad conical head was designed

to pierce through the wood

and with virtually no friction against a narrow foreshaft,

it pushed straight through.

- Once that conical spear tip punches through

it makes the shield useless and you have to put it down,

or you can try and pull the thing out,

but then the shaft bends.

It's designed to be a single use weapon

that can't be returned

and it's gonna impede the enemy's ability to defend himself

at best, and at worst,

it's gonna go straight through his armor and kill him.

- [Narrator] A merciless master stroke

by the Roman weapon designers

that helped their empire conquer the ancient world.

But keeping the entire Roman army equipped

with a single-use pilum,

would have been a daunting prospect.

- You take an ingot of tempered iron

and you heat it and beat it into shape,

it's quite a complicated piece of forging.

Each soldier has at least two of them.

There are 5,000 soldiers in a legion.

So you can imagine there would be blacksmith and armorers

traveling with the troops all the time,

making and repairing these things.

- If you imagine the Roman empire with all its legions

and all of them need equipping.

Now that's a vast amount of equipment:

swords, pilums, et cetera.

So it's no known example of a Roman army

ever going into battle underequiped.

- [Narrator] Regardless of the sophisticated manufacturing

of a single pilum,

and the sheer volume required to keep the legion supplied,

the industrial complex of the Roman arms industry

was up to the challenge.

Despite its ancient history, forging remains

one of the most effective ways to shape metals,

creating structural components for all variety

of tools, machinery, and weapons.

But modern engineers have increased the efficiency

beyond the imagination of a Roman blacksmith.

Today, giant mechanical forging hammers are employed,

which use non-muscular power as their source of energy.

- So essentially this huge hammer

that under either electrical or steam power,

is accelerated down, to crush whatever is underneath it,

under huge pressure.

- [Narrator] Hitting hard and hitting accurately.

- It is heavy engineering at its most powerful.

You really do feel, the might coming from these machines.

- [Narrator] Even a small personal power hammer

can carry out the work

of two stout adults with sledgehammers,

while the largest hits with the force equivalent

to the weight of a blue whale,

compressing hot metal with ease.

(armies marching)

The Romans had engineered the spear

into a formidable piece of equipment,

but these weapons were thrown

a relatively short distance of only a few dozen feet.

To extend the range and impact of a projectile,

early humans had to devise a way

of increasing the force with which it was propelled

while also being more accurate than the atlatl

and constructed a weapon more than 60,000 years ago,

that would change the landscape of warfare for millennia:

the bow and arrow.

- Initially the bow and arrow

would've been used as a hunting weapon

to give humans the food that they needed to survive.

The materials are apparently simple,

but actually the technology behind it is quite complicated.

- [Narrator] Consisting of a wooden stave,

flexible enough to bend and curve with pressure

and held in tension by a string.

When an arrow is then drawn back,

enough tension is produced in the bow

to propel it forward when released.

- When you stretch the bow itself,

it puts an enormous amount of tension into the materials

and that stores potential energy.

And then when you let that go,

the tension is released,

that potential energy turns into kinetic energy,

movement energy,

which fires the bow at enormous speeds

and acceleration towards the target.

- It's the first time

that we can actually store kinetic energy

and it's waiting to be released

at a speed far, far faster

than we could actually achieve with our own muscles.

- [Narrator] The bow and arrow was the perfect hunting tool,

as the archer could aim with slow and steady movements,

keeping them hidden from prey.

The invention of this new stealth weapon

was a massive advance

in projecting a missile towards the enemy

and eventually began replacing the atlatl

over the millennia.

But this was only the initial design.

- The ranged weapon gives you an advantage,

not only in conflict with other human beings,

but also in hunting.

But human ingenuity, being what it is,

over time improvements were made to the bows.

- [Narrator] By 1200 AD,

a much more efficient form of bow made its appearance

known from its method of construction,

as the composite bow,

a smaller and lighter weapon

that provided much greater power.

- So here we have another small step

in the evolution of weaponry.

The ranges are getting better.

The penetrating power is getting better.

It gives a competitive advantage

in terms of warfare to whoever's got this composite bow.

- [Narrator] The secret behind its success,

a combination of specially chosen materials

that form the bow itself.

- The amazing thing here with the composite bow,

is it gives us a real snapshot

into the engineering ingenuity

of the human beings who invented it.

So this is an incredible engineering solution

showing real skill on the part of the designer.

- Now the middle of the bow is the neutral plane.

It's not in compression, like the belly,

and it's not in tension, like the back.

So it's just subject to sheer forces,

so you need something that's gonna withstand that.

- [Narrator] Craftsman began with a piece of wood

that other materials would be bound to.

Thin strips of buffalo or cow horn

were added to the inside of the bow

as it can store more energy than wood in compression.

This was the engine of the bow, which kept its shape

and acted as a powerful spring while firing.

Animal sinew was then placed on the back of the bow,

which stretches farther than wood

and therefore stores more power.

- The sinews must be pulverized down

to make thin fibers, that's laid on with a glue,

usually an animal glue.

And the finest glue that you can use is isinglass,

which is made of the swim bladders of sturgeons.

It's quite waterproof.

So you can think of that

as a very early version of fiberglass.

- Buffalo horn stores far more energy

than timber when it's compressed,

and animal sinew stores far more energy

than timber when it's stretched.

So the combination of the two

made that bow so much more powerful.

- [Narrator] Making a composite bow

was a highly developed technology,

but also an incredibly expensive and time-consuming process.

The new smaller bows could fire lighter arrows

up to 600 feet, with the advantage of

reaching only from the head of the archer down to his waist,

a ranged weapon with a potential to become

even more lethal on the battlefield.

- The amount that you can strain sinew and cow horn

is far in excess of what you can strain wood.

So you can shrink the design right down

to enable you to be able to use in a lot more circumstances.

- A crucial aspect of the design of the composite bow

was that it was quite short in comparison to previous bows.

And that meant that you could use it on horseback.

- [Narrator] It's been claimed that horses

were first used to pull wagons or chariots in battle

as far back as 2,500 BC.

Centuries later, warriors themselves

then began to fight on horseback,

armed with any number of melee weapons,

but the invention of the composite bow allowed for an

entirely new breed of warrior:

mounted archers.

- It's a different way of fighting

combining cavalry and missile troops

so they're attacking you when they're coming forward,

they're attacking you when you are retreating.

Infantry would really struggle against that.

They're not even gonna get close to them.

- [Narrator] Its greatest efficiency was seen in Mongolia.

- The mounted archer was the key to Genghis Kahn's success.

He seized one of the greatest empires in all of history

by using armies of mounted archers.

And those archers

could move with great speed across the plains.

- Genghis Khan, the greatest warrior of the Mongols,

you can really envisage him, riding across the Asian step.

Riding across Europe, fighting his opponents,

using his bow and arrow from his saddle

as though it was his second nature.

- [Narrator] A masterful piece of military engineering,

more compact and more powerful than previous bows

that helped establish

one of the largest empires in the world.

While Genghis Kahn was conquering,

the bow and arrow was being engineered further in Europe

into one of its most recognized

and arguably most deadly forms:

the longbow.

- The longbow is a very long, body-sized, self bow.

And because it's so large,

it had incredible penetrative power in terms of the arrows

and also range.

- [Narrator] And the material used to construct the longbow

was just as important as its size.

- The beauty of the longbow is its simplicity.

It's made from a single piece of wood

so its incredibly robust

and actually quite quick to produce.

- The really clever engineering feat

with the longbow,

is how the wood was actually removed

from the yew tree it came from,

because you have the heartwood on the one side,

but also the sapwood as well,

so the harder wood and the softer wood.

So effectively, this is a natural composite bow.

- [Narrator] The different qualities

of the two types of wood compliment each other,

combining tension and compression.

- The combination of those

two types of wood meant that it was far more powerful

than any bow than had ever been invented before.

- [Narrator] With a maximum effective range

of over 1000 feet,

a fully trained longbowman could be devastating,

firing an arrow every five seconds.

But there was a downside.

- The problem with the longbow

is that they could only be made

out of one particular type of wood.

And because of that, it almost wiped out

the entire population of yew trees in Europe.

- [Narrator] Armed with nothing more than axes and saws,

the medieval lumberjacks almost eliminated

one of the world's longest living tree species.

Today, crude hand tools

have been replaced by powerful machinery

as engineers continue to develop new ways

to gather materials

in an effort to meet the growing global demand.

And the timber industry is no exception.

- In the days when people needed to use wood

for things like weapons,

they would've had to have taken almost a day probably,

to chop down one of these enormous trees,

to fell it, to de-limb it,

and to chop it to the size they needed.

- [Narrator] What used to require

a small army of lumberjacks with saws and axes

is now achieved with a single machine and operator:

timber harvesters.

Self-propelled cutting machines

each with an extendable arm and cutting head

that allow them to fell, strip,

and chop trees to exact lengths as if they were twigs.

- The speeds at which these machines can work

is out of this world.

They can chop down 600 trees a day.

That's over 200,000 trees a year.

- [Narrator] Incredibly efficient machinery

fueled by the needs of the modern world.

Thanks to the natural resources

the ancients had at their disposal,

the bow and arrow was engineered

into the dominant ranged weapon

for hundreds of years of human history.

But there was a downside.

- Like any weapon, a highly physical activity

will actually sap the soldier over time.

This is gonna be really draining

over the course of a battle.

- Even with the best training in the world,

you can only use a bow for so long

before you become physically tired

and your ability to use it effectively diminishes.

- [Narrator] However,

several hundred years earlier in the sixth century BC,

an engineering innovation was made

in one of the world's oldest civilizations.

The Chinese had devised a new and improved ranged weapon.

One that would put far less strain on the archer:

the crossbow.

- The crossbow was an absolute game changer

in this period of ranged weapons designed.

You could fire a bolt with immense speed

and huge destructive power with very little training indeed.

- A crossbow gives you many advantages

over a traditional hand bow.

Once you've cocked the weapon,

it's actually preloaded

and then you can shoot when that's convenient to you.

You're aiming it more in the way that you would aim a rifle.

- [Narrator] The bow was fixed

crosswise on a wooden frame

with grooves to guide the projectile.

The string was pulled back and held in position

by a latch attached to a trigger mechanism.

- Now the crossbow is a huge jump

in weapon design and engineering.

So suddenly, with the bolt in place,

we can aim it and take our time

because we are not

physically holding the string with our own muscles,

it's on the catch.

And when we're ready,

we can then release it through the trigger.

- [Narrator] This trigger mechanism

could be conceived as

the ancestor of the trigger from a modern rifle.

- The trigger mechanism of a crossbow

was very difficult to manufacture

and it involved incredibly detailed

and very accurate casting.

There were several moving parts and very intricate pieces.

They all had to be put together perfectly

or that simply wouldn't work.

- [Narrator] Crossbows could be held ready armed

for long periods without tiring the archer

and so taking aim became easier.

- You can create that tension

to hold the potential energy there

while you're finding your target.

Essentially just use a trigger to release

when you are ready and you've got the target in the sight.

It's much easier for humans to use.

- [Narrator] When released, the crossbow bolt

could fly over 800 feet towards the enemy,

tearing through armor, flesh, and bone.

- I have held a loaded crossbow

and you can feel the power of the weapon in your hands.

Believe me, you would not want to be in the line of fire

of one of these things.

- This weapon created a more detached way of killing.

You no longer had to look your enemy in the eye.

- [Narrator] Huge destructive power,

unleashed by simply squeezing a trigger.

There are obvious heirs

of the propulsion mechanism of the crossbow,

including the modern rifle or revolver,

but also a surprising one, on a much grander scale.

Aircraft carriers are one of the largest examples

of naval force in the world.

- These aircraft carriers are huge;

think huge floating cities,

and they have the potential for plane to land

and to take off on them.

Absolutely extraordinary.

- Despite the enormous size of these aircraft carriers,

it's still only

a fraction of the length of a runway on land.

When you've got these aircraft

that need to reach their takeoff speed,

they've got to do that over a much shorter length.

- [Narrator] Runways of around 300 feet

in the middle of the ocean,

less than 3% of the total distance seen

at London Heathrow airport's Northern runway.

- To get these aircraft to the takeoff speeds

they need over such a short space

means they need an additional device to help them.

And this is the catapult

that's on board the aircraft carriers.

- [Narrator] A small shuttle on the flight deck

that connects to the aircraft,

capable of accelerating from zero to over 170 miles per hour

in less than two and a half seconds.

- This catapult system doesn't look like much above deck,

but underneath you've got the engineering magic

that lets this aircraft take off at such high speeds.

- [Narrator] A catapult consists of two pistons

that each sit inside a long cylinder underneath the deck.

The pistons, attached to the small shuttle,

which will pull the aircraft at launch.

High pressure steam is collected in large tanks

until the desired pressure is reached

and the catapult is then ready to fire.

When the steam is released,

the pistons act like bullets,

as the pressure rockets the shuttle and plane forward.

- That pressure forces the plane to take off

with this kind of catapult effect

without actually having the excessive length of runway

that we use more traditionally.

- [Narrator] The aircraft catapult

provides the necessary force

to sling a 45,000 pound plane forward

to generate the necessary lift for takeoff.

Chinese military innovators

were centuries ahead of the rest of the world,

bringing inventions into existence

that redefined engineering.

- Ancient Chinese military heritage

is often at the root

of many innovations that we use in the West.

- It's very easy to forget

that what was going on in China a thousand years ago

was phenomenal.

Some of the innovations we see coming out of China,

are really quite remarkable.

- [Narrator] By the ninth century AD,

China's engineers and blacksmiths

were becoming experts at creating deadly weapons,

and we're on the verge of a truly volatile invention.

- The Chinese were actually after the secret of eternal life

and they were messing around with potions and ingredients.

Ironically, it led to the invention of something

which has taken more lives

than perhaps anything else in the history of the world.

- [Narrator] Gunpowder: a violent explosive

produced by mixing saltpeter, sulfur, and charcoal.

- These three items by themselves, innocuous,

not particularly harmful,

but combined together create a compound

that is explosive in its nature.

- They've got lots of gas released

in a very short space of time,

which creates a lot of explosive power.

- [Narrator] Originally used

to produce fireworks and rockets,

it didn't take long before

its enormous potential was recognized by the military.

- Gunpowder is a huge leap in technology

because you're not storing kinetic energy anymore

in the way that you were with a crossbow

or even the earliest Stone Age bow,

you've now got chemical energy,

and the sky's the limit with something like that.

- [Narrator] Gunpowder would eventually become

the most effective ingredient for weapons of war.

Used to create explosives, such as bombs and grenades,

eventually leading to the most deadly weapon of all

in the 20th century:

the nuclear bomb.

Yet almost a thousand years earlier,

the Chinese engineers were only just beginning

to realize gunpowder's potential on the battlefield.

If inserted inside a narrow tube or cylinder,

gunpowder created enough explosive force

to shoot a projectile out at great speed.

- Suddenly you could project something

towards an enemy much further, and with far more power

than ever before.

It was terrifying.

No one had ever seen anything like this ever before.

- [Narrator] While these early firearms

were a frightening new weapon on the battlefield,

they were difficult to operate

and nowhere near effective enough

to replace the already established ranged weapons

used by their enemies.

To truly harness gunpowder's extreme power,

China's engineers had to think bigger.

Over the next centuries,

the Chinese somehow managed

to continue to monopolize gunpowder, until the 13th century.

In that time, the same principle used in the early guns

was applied to a new form of weaponry

cast metal weapons,

large enough to batter down buildings

as well as people:

cannons.

- The Chinese were always very ambitious

with their inventions,

and they were obsessed with scale,

and they applied this to gunpowder

and that's how they invented the cannon.

It was simply enlarged versions of the small hand cannons.

- What we see being engineered are huge metal cannons.

These things are pretty much indestructible

and they can be used to do much more damage.

- [Narrator] By lighting a fuse,

the flame would be carried into the breach of the cannon.

Inside, the packed gunpowder burned rapidly,

producing expanding hot gases

that applied huge amounts of pressure on the projectile.

Instead of arrows,

enemies now had to dodge

gigantic cannon balls hurdling towards them.

Eventually, the Chinese could no longer

keep the science of gunpowder a secret

as it was passed along the ancient silk trade route

to Europe and the Islamic world

where it would rain havoc

on many battlefields of the middle ages.

- When the Europeans heard about gunpowder,

they decided to apply their own scientific genius to it.

They wanted to improve it.

- [Narrator] Europeans refined the mix of gun powder,

maximizing its explosive potential.

- We see quite advanced milling technology

being used to grind down all of those constituent parts,

the saltpeter, the sulfur, and the charcoal,

into a really fine powder.

You introduce water into that mix

and what you get is a really fine paste

and you can take particles, almost microscopic scale,

and then mix them together.

And it's that refinement in the mix

makes a powder that is that much more potent.

- What matters most with gunpowder

is the uniformity of the powder that you produced.

And that's what the Europeans changed.

As a result, they developed a version of gunpowder,

which was a far more powerful mix.

- [Narrator] But a more volatile gun powder

called for better engineered cannons.

Many designs involved long rods of wrought iron

that were heated,

aligned around a wooden core, and beaten into shape

Before a white hot iron hoop slotted over the form.

These would hold the rods firmly in place

as they cooled and shrank creating the barrel of the cannon.

- That's what creates your early medieval cannons, okay?

But these things are pretty dangerous.

And I can't imagine that particularly accurate.

- [Narrator] The fierce heat and force

generated by each explosion

meant that the cannons were extremely temperamental.

(Canon firing)

They needed a new design.

The Europeans were years behind the Chinese at this time,

but they were highly accomplished in one technology:

bell casting.

- Europeans had quite a lot of experience

working with bronze

and there's actually huge deposits of tin and copper

here on British Isles.

So the logical conclusion was to take that method of casting

and to use it to cast large cannon.

- [Narrator] While early Chinese hand cannons and bombards

were also made from bronze,

these were a far larger and destructive form of cannon

and the assembled breach-loading designs

made of a wrought iron, were seen as inferior

to the new muzzle-loading cannons cast of bronze,

an expensive alternative

but far more powerful and safer to use.

Since it's creation around 850 AD

gunpowder formed the basis

for almost every weapon used in war

from that point on,

as bows and catapults were replaced,

with rifles and cannons

responsible for the deaths of tens of millions

over the centuries.

Gunpowder helped bring an end to the medieval ages in Europe

and played one of its most significant and destructive roles

during the age of exploration and colonial expansion.

- Cannons were used in siege warfare

against towns and against castles,

but perhaps most importantly,

they were mounted onboard huge sailing ships,

which could sail right across the world.

- [Narrator] Bold technology

had been used in warfare since antiquity,

but by combining sailing ships with cannons,

the Europeans had engineered a super weapon

that other cultures had no defense against.

- It's one thing sailing around the world with ships

trading and exchanging,

but the moment you arm those boats with cannons

is the moment at which you can use force

to get what you want from the four corners of the planet.

And that's exactly what happens.

- [Narrator] With rows of cannons on their ships,

the Europeans swept across the world's oceans,

expanding their trade networks and empires

while exploiting the natural resources

and indigenous peoples that they encountered.

By 1900, the vast majority of countries

were either Western themselves or under European control

with gunpowder acting as a key driving force.

Cannons were the pioneers

of a new class of heavy ranged weapons

built to launch munitions

far beyond the range and power of infantry firearms:

(artillery firing)

artillery.

- Artillery is one of the earliest remote forms of weaponry.

Instead of being within throwing range

or striking range of the opposition,

you're using engineered solutions to throw

projectiles and all sorts of things at your opposition.

- [Narrator] Since the introduction of cannons

centuries ago, artillery has played a decisive role

in numerous major battles,

responsible for 60% of the battlefield casualties

in World War I alone.

- From the World Wars, artillery has always been critical.

It's always been a way to show our power,

show our might on the battlefield.

- [Narrator] Military engineers continue to design

ultra long range artillery systems with lethal capabilities,

well beyond the limits of anything previously achieved in

the history of warfare.

The US Army's standard 155 millimeter Howitzer

has a range of up to 14 miles,

with technological advances being made to the projectile

expected to quadruple that distance.

- There's huge amounts of might

behind this engineering that really takes you a step forward

in the destruction that you can cause.

- It's always been about

increased precision and increased power.

It's the ability for a conflict to be over

as quickly and as efficiently as possible.

- [Narrator] A world of weapons and warfare

capable of creating a level of destruction

unimaginable to our ancestors.

The evolution of a ranged weapon

enabled the ancients to expand, explore, and conquer.

Engineering innovations that drove human history

while leaving harm and suffering in their wake.

Whether for good or for bad,

these inventions are part of the human journey

traced back to the earliest ancient engineers.

(triumphant music playing)