Original subtitles

NARRATOR: Can a sphere the size of a pinhead be a murder weapon?

This weird tiny sphere was found embedded

in the body of a dead man.

NARRATOR: Does this Medieval machine predict the future?

It is said to have belonged to a man that allegedly

predicted 9/11 or the rise of Hitler centuries

before they happened.

NARRATOR: And did this high-tech bird cage

really save the lives of thousands?

It actually became illegal to not use these birds.

NARRATOR: These are the most remarkable

and mysterious objects on Earth,

hidden away in museums,

laboratories, and storage rooms.

Now, new research and technology can

get under their skin like never before.

We can rebuild them,

pull them apart,

and zoom in

to reveal the unbelievable,

the ancient,

and the truly bizarre.

These are the world's strangest things.

In London's Crime Museum is a minute metal sphere,

just 7/100ths of an inch across.

AUERBACH: This object is minuscule.

It's smaller than the head of a pin.

But it's capable of killing someone.

NARRATOR: It is the only hard evidence of a crime

that has confounded police for almost half a century.

Now, using the latest technology,

we're bringing this mysterious object to life.

This weird, tiny sphere was found embedded

in the body of a dead man.

The sphere, at first glance, looks really innocent,

but the devil is in the details.

NARRATOR: The sphere is made from two of

the rarest, most valuable metals in the world.

It's covered in tiny scratches,

but there are also these holes that run through it.

NARRATOR: The holes are just four times

the width of a human hair.

BENECKE: The two holes meet in the middle,

so they form a cross-shaped pattern.

What was inside?

NARRATOR: What are the microscopic holes for?

Who made this strange sphere?

And how does it become the center of one

of the most bizarre true crime stories of our time?

London, September 8th, 1978, 11 p.m.

49-year-old Bulgarian playwright,

Georgi Markov is rushed into St. James Hospital.

Markov is really in a terrible state.

He's been complaining of pain, nausea.

He's been vomiting, he's got a really high fever.

He's had dizziness, and he's in an awful lot of pain.

His white blood cell count is sky high,

and it's just not making any sense.

And on September 11th, Markov suffers a cardiac arrest.

At 10:40 a.m., he's pronounced dead.

MARKS: The doctors give the cause of death a septicemia,

which is blood poisoning caused by bacteria

getting into the blood.

AUERBACH: That's really just the doctor's best guess.

They are stumped.

They don't know what could cause what was, at the time,

a perfectly healthy man to

decline so rapidly and so dramatically.

NARRATOR: Before he dies, Markov tells doctors that

he thinks he's the victim of a hit.

Markov had defected from Bulgaria

a decade earlier and subsequently moved to England.

NARRATOR: In Bulgaria,

he'd been an acclaimed playwright and satirist.

But since moving to the U.K.,

he'd become one of the Soviet-backed regime's

most prominent critics.

The ruler of Bulgaria, Zhivkov, is a dictator.

This is not a man who's going to tolerate contradiction,

dissent, or criticism.

NARRATOR: A potential assassination gets

the British police's attention.

Scotland yard orders an autopsy of Markov's body,

because they know he's a Bulgarian defector,

and the circumstance of his death are suspicious.

When they complete their investigation,

they do find a tiny pinprick, as if he had been injected

with something.

NARRATOR: They excise the wound site and send it

to the U.K.'s top secret biochemical weapons

research center,

Porton Down.

MARKS: The team at Porton Down

slice through the flesh with a scalpel, and it hits a tiny

metal sphere, which is only 7/100ths of an inch across.

NARRATOR: This is that minute sphere,

magnified almost 1,000 times.

Could something so tiny really be connected to Markov's death?

SELLA: We know that there are all kinds of

poisonous metals out there,

whether it's mercury or thallium, you know,

there's a whole series of things in the periodic table

which are unquestionably bad for you.

NARRATOR: So, is Markov killed by toxic metal?

SELLA: The analysis of this little sphere showed

that it consisted 90 percent of platinum

and 10 percent of iridium,

and those two metals are in a group in the periodic table,

which are referred to as the noble metals.

These metals are incredibly

chemically and also biologically inert.

There's no way that the sphere itself, on its own,

can explain the strange death of Georgi Markov.

NARRATOR: So what does kill Markov?

Two weeks after the attack on Markov,

The British police receive

a call from the French capital, Paris.

It turns out that on August 26th,

2 weeks before the Markov incident,

another Bulgarian defector,

a chap named Vladimir Kostov, reports that, as he was exiting

a Paris metro station, he felt

a stinging sensation in his back.

NARRATOR: Kostov falls ill with almost

exactly the same symptoms as Markov.

But unlike Markov, he survives.

AUERBACH: When doctors investigate further,

they find something very familiar --

a tiny pinprick in his back, and in that pinprick,

a minuscule metal sphere.

On Tuesday, a metal object was removed from the back of

Mr. Kostov, and our scientists have now examined this,

and we're quite satisfied it's identical in size

and composition.

NARRATOR: Police are now convinced

the metal sphere kills Markoff.

So, it can only be

something contained within the microscopic holes.

Whatever the substance was,

It was only a fifth of a thousandth of a gram,

and that was enough to kill a grown man.

BENECKE: Most of the chemical agents known, for example,

cyanide or arsenic, need much higher amounts of the chemical

compared to what was seen in Markov.

So synthetic toxins could be crossed off the list.

NARRATOR: There is just one class of toxin that might fit.

The toxic substances that are left are now biological

substances, for example,

those that you could extract out of spiders, snakes,

plants or any other biological living being.

NARRATOR: And one biotoxin in particular

stands out from the rest.

BENECKE: Inside of the holes

was a poison, which is very, very dangerous and quite lethal.

NARRATOR: And there is no antidote.

NARRATOR: British scientists have finally identified

the poison concealed inside the sphere

that kills Georgi Markov...

...ricin.

Ricin is really easy to get, because it comes out of

castor oil beans,

and the oil itself is not dangerous,

but the waste that remains in huge amounts

contains the highly toxic substance ricin.

NARRATOR: When ricin enters the bloodstream,

it blocks cells from producing essential proteins.

The reaction in the body is rapid and extremely dangerous.

Ricin causes vomiting, a very high white blood cell count,

fever, sweating, abdominal pain.

This is all very typical for poisoning, and since Markoff

had exactly those symptoms,

this is a clear sign that he was poisoned with ricin.

NARRATOR: So why doesn't Kostov die in Paris?

The French sphere turns out to be identical

to the Markov sphere in all respects except one.

The holes are not empty.

They contain tiny amounts of a substance --

not poison, but something quite innocuous...

wax.

NARRATOR: Investigators believe the wax acts as a plug.

So the sphere itself is simply

the delivery mechanism for this poison.

The poison is tucked away inside, capped with wax.

NARRATOR: Until the sphere enters the body.

SELLA: At that point, it warms up

and releases the goods.

NARRATOR: Scientists suspect

that Kostov's survival is dumb luck.

The sphere enters part of his back

where there are fewer large blood vessels.

So by the time the wax melts and the poison starts to

circulate, his body has begun to protect itself.

In Kostov's case, there was blood clotting taking place,

and this prevented poison from

getting out of the little sphere.

NARRATOR: Markov is killed by a speck

of ricin contained in this microscopic sphere.

But the truly bizarre story is how

it gets into Markov in the first place.

Before Markov dies, he tells hospital staff a strange tale

that sounds like something out of a John le Carre novel.

On the afternoon of September 7th,

Markoff was on his way to work at the BBC.

He crosses Waterloo Bridge, and as he's waiting

at a bus station,

he feels a sharp jab in his thigh.

He hears someone say, "I'm sorry,"

looks around, and sees a man he doesn't recognize

pick up an umbrella and step into a cab and speed off.

Only hours later, he starts to feel all

these terrible symptoms.

NARRATOR: Is the umbrella a weapon?

There's no way to know, because

the umbrella and the suspect have disappeared.

Within a year of Markov's death,

the police case has stalled.

It is 10 more years before they catch a break.

[indistinct shouting]

AUERBACH: On the 10th of November 1989,

one day after the fall of the Berlin Wall,

Zhivkov is ousted as the dictator of Bulgaria,

communism there falls, and the secrets start to tumble out.

Investigators exploring the Communist Interior Ministry

make a startling discovery -- they stumble upon a stack of

these umbrellas modified to fire tiny metal pellets.

NARRATOR: Now, investigators know the umbrella gun is

real, and they understand exactly how it works.

MARKS: This device looked like any normal umbrella.

When you pushed the button to open the umbrella,

it acted as a firing trigger, and this released a gas stored

in the cylinder in the stem of the umbrella.

The gas propels the sphere with

enough force to pierce through the flesh.

NARRATOR: The police now know precisely how Markoff died.

The one thing they don't know is who pulled the trigger.

There's a lot of people who come under

suspicion as possibly being the man with the umbrella.

NARRATOR: Among them is a man thought to

be associated with the Bulgarian government,

Francesco Gullino.

He's known to have made several trips to London,

including one right around the time of

Markov's assassination.

And it's also known that he left for Rome the day after.

Evidence puts him at the right place and the right time.

And Gullino is questioned by the international police

in 1993.

NARRATOR: But the evidence is circumstantial at best.

Gullino dies in August 2021.

Nobody has ever charged with Markov's murder.

Even now, more than 40 years after Markov's death,

the only solid evidence we have of his assassination is

this strange metal sphere no bigger than the head of a pin.

Whoever was ultimately responsible for this attack,

one thing is certainly true --

sometimes, very, very bad things come in very,

very small packages.

NARRATOR: At Oxford University's History of

Science Museum is an extraordinary device.

This elegant, intricate contraption is

hundreds of years old,

and it straddles the borderlands between science

and superstition.

We are still trying to understand

how exactly they work.

NARRATOR: Now, using the latest technology,

we are going to open up this incredible instrument, layer by

layer, to uncover its hidden secrets.

It measures nearly 8 inches across.

Intricately etched plates and dials cover

both faces, and it changed the way we look at the universe.

It can predict everything that is going on in the heavens.

NARRATOR: But it was intended for more than astronomy.

This one in particular has a series of markings

and inscriptions that indicate

that it was also used in connection to medicine.

NARRATOR: But what makes this device truly

special is the identity of its owner,

[speaking German]

someone who is claimed to

have prophesied world-changing events.

It is said to have belonged to a man that allegedly

predicted 9/11 or the rise of Hitler centuries before

they happen.

And this man was Nostradamus.

NARRATOR: Experts believe this could be

the device Nostradamus used to

make his infamous predictions.

Essentially, it is a kind of

way of predicting what the future is going to bring.

NARRATOR: What is this extraordinary machine?

Is it really a medical device?

Who is Nostradamus?

And can he really use this to predict the future?

This beautiful device is an astrolabe.

BALL: The face of the astrolabe is a kind of

two-dimensional map of the night sky.

Overhead, there is this dome

of the night sky, and it's projected

onto this flat sort of two-dimensional system in

much the same way that the surface of the Earth is

projected onto a flat surface in an ordinary map.

ESCOLANO-POVEDA: The name comes from the Greek,

so astrolabe means the taker of the stars,

and it's a very nice image, because you are

able to encompass the whole of the universe with this tool

you can hold in your hands.

BALL: An astrolabe has various moving parts that allows one to

predict the altitude of

a particular star above the horizon at a particular time

and place of the year.

So it's really a device for making sense of the night sky.

NARRATOR: But it's so much more than that.

ESCOLANO-POVEDA: It could be used to measure distances,

to calculate the heights of buildings.

It could be used to forecast tides.

ESCOLANO-POVEDA: There were special astrolabes

that were used for navigation.

One 10th century philosopher suggested that there

were a thousand uses for the astrolabe.

NARRATOR: This is one of the most stunning in existence,

because it's not just an astrolabe.

BALL: It's really two devices in one.

NARRATOR: One face is the star predicting astrolabe,

while the device on the opposite face is for the planets.

BALL: This is called an equatorium.

The planets are harder to follow, because unlike

the stars, they're moving much more.

That's, in fact, what planet means.

It means wanderer.

These were -- seemed to be star-like objects

that wandered around the sky.

It extends both into the past and into the future.

So you can predict really at any time in

the future where the planets are going to be.

You can also project back into

the past to predict where they were.

So really, this device gives you, in one package, a way of

understanding and predicting the movements of the entirety

of what you could see in the night sky.

NARRATOR: An astrolabe and an equatorium

in a single device is virtually unheard of.

ESCOLANO-POVEDA: That's really rare.

We only have three that have come down to us,

and we are still trying to understand

how exactly they work.

NARRATOR: But one thing is clear --

this is a high-precision instrument.

ESCOLANO-POVEDA This astrolabe is not only really beautiful

and really breathtaking to look at, but it's also very precise.

Very complex calculations go into making all these scales,

all these different parts.

NARRATOR: But did this rare and specialized piece

of equipment really belong to the infamous Nostradamus?

We have very strong clues to

the identity of the astrolabe's owner.

Records show the astrolabe belonged to

a rich French family called the d'Hautevilles,

and they had a very famous neighbor.

ESCOLANO-POVEDA: Nostradamus,

or Michel de Nostredame, lived very close

to the d'Hauteville family for the last 19 years of his life.

NARRATOR: Living in the same small French town,

it's inevitable these prominent citizens

would have known each other well,

and when Nostradamus died, it's thought the d'Hauteville

family may have acquired his astrolabe.

They were certainly one of the few families in the region

wealthy enough to have bought it.

Another clue is inscribed on the astrolabe itself.

ESCOLANO-POVEDA: We have this inscription, iniciv morbi,

which means the onset of sickness,

which would be used to calculate the beginning

of fevers.

Fevers normally happen at particular points

throughout the year,

and this would need to be calculated.

NARRATOR: This rare inscription regarding illness is

significant, because Nostradamus is a doctor.

Nostradamus was a physician, and he also had the economic

power at the end of his life to acquire such a complex

and expensive instrument.

So if we put all the pieces together,

there are many chances that these astrolabe could have

actually belonged to Nostradamus.

NARRATOR: But why does a famous doctor need

a device that reads the stars and planets?

In the Middle Ages,

astronomy and astrology are an integral part of medicine.

There was a belief at that time that there was

a correspondence between what

was happening in the heavens and what was happening on Earth

and in the body.

Each one of the Zodiacal constellations had particular

characteristics that would transfer

those characteristics to that part of the body.

So Aries got the head, Gemini got the shoulders, and poor

Scorpio ended up with the genitals.

NARRATOR: The Zodiac constellations also

take the blame for specific illnesses.

Pisces, Cancer, and Capricorn

cause diseases involving sores, scales, and fistulas.

While Sagittarius and Gemini are responsible

for falling fits or epileptic seizures.

NARRATOR: And planets have their own unique role in

medieval medicine.

STEELE: Planets were in charge of really rather

random collections of parts of the human body.

For example, Saturn controls the right ear and the spleen,

while Jupiter controls

the lungs and arteries, and poor Mercury gets speech,

thought, and the buttocks.

NARRATOR: So the astrolabe is a vital

diagnostic tool for a doctor like Nostradamus.

ESCOLANO-POVEDA: Nostradamus would use the astrolabe in order

to calculate the horoscope of this person

and see where the sun, the moon,

the planets, and the stars were at the birth of

this particular person.

Secondly, the time they got ill, as its

Zodiac characteristics had to be assessed.

And thirdly, a decision would need to be made about the best

day to try bleeding, bathing,

sweating, and so on based on the locations and phases of

the moon in the Zodiac --

another job for the equatorium.

NARRATOR: Nostradamus then looks to the astrological sign

that rules over the diagnosed disease.

STEELE: So Nostradamus would have known that if

the problem was with the spine, then the orbit

of the sun would have been important, while if it was

the liver, then Jupiter needed to be tracked,

all of which could be done with his equatorium.

NARRATOR: All this seems a long way from supposedly predicting

the rise of Hitler and the assassination of JFK.

So what transforms Nostradamus from a medic into a prophet?

And what does this strange device have to do with it?

NARRATOR: In the 16th century, Nostradamus works as

a physician, using the astrolabe to treat patients.

But it's a bad time to be a doctor.

STEELE: The continent was ravaged by plague,

which was an incredibly deadly disease.

And nobody knew what caused it.

It seemed to strike without apparent rhyme or reason.

NARRATOR: When Nostradamus's wife and children are killed by

the plague, he begins to move from medicine towards

the occult and his infamous prophecies.

Nostradamus tried to find a way of predicting what was

going to happen so that he could

be ready for another plague or another disaster.

NARRATOR: He spends hours meditating.

He has hallucinations or visions.

These inspire his prophecies, which he then

refines with the predictions of the astrolabe.

This ability to be able to say at such and such a time

on such and such a day,

this planet will be here and this star will be here,

this would have looked like an astonishing,

almost a magical capability.

NARRATOR: The result is his 10-volume

compendium of prophecies called the Centuries.

But to avoid problems with the powerful Catholic church,

Nostradamus deliberately obscures his prophetic writing.

What he did was use

metaphorical language and also words in different languages --

Latin, Greek -- in order to predict the future,

but also to do it in, like, a veiled way.

One example says, "The great man

will be struck by a thunderbolt,"

and this has been associated

with the murder of JFK.

But of course, this is a very broad statement.

A great man could be any kind of ruler, and a thunderbolt

could be a gunshot, but it could also be a real

thunderbolt or any other kind of violent event.

NARRATOR: Nostradamus is also supposed to

have predicted the rise of Hitler.

ESCOLANO-POVEDA: One of these lines

says that in the west of Europe,

a child born of poor parents will rise,

but many people were born from poor families

and then have obtained powers.

So the problem of using this veiled language to present these

predictions is that you can basically make them work

for everything.

NARRATOR: But there is one prediction

Nostradamus doesn't obscure.

ESCOLANO-POVEDA: In the evening prior to his death

in July 1st, 1566,

he said to his secretary that he wouldn't be found alive in

the next morning, and then he died the next day.

But of course, if you're going to die during the night,

you probably don't feel very well

in the evening of that day.

NARRATOR: Debate over the accuracy of

Nostradamus's predictions will run and run.

One thing we do know --

Nostradamus claims all his prophecies are based

on astrological calculations

that he may have made with this

astonishing astrolabe.

In a cabinet at the Science Museum

in London sits a very odd device.

It's such a strange-looking contraption.

Does it do good or does it do bad?

NARRATOR: It helped save thousands of lives

all over the world.

This strange thing was found in some

of the deepest, darkest holes in the world.

And it proved to be an incredibly

simple solution to an industrial-sized problem.

NARRATOR: Now, using the latest technology,

we are bringing this amazing machine out of the darkness

and into the light.

Measuring around 10 inches tall and 4 inches wide, this...

is the canary resuscitator.

This simple metal-framed glass box changes the world.

It actually became illegal to not use these birds.

NARRATOR: So what is this strange device?

What inspires its creation?

How does it save people's lives,

and why is there a tiny bird inside?

In fact, that tiny bird is crucial

to how this machine works.

MARKS: Essentially, what you've got here is

the world's most high-tech bird cage.

It's not so bad for the bird -- from inside it can see out,

it's got windows.

But the key thing about it is that it's supposed to keep

the bird alive in a place where the atmosphere

should kill it.

NARRATOR: 110 years ago, the construction of this bird

cage is cutting edge technology.

SOMARA: It's a very engineering-focused device.

There are screws, there are panes of glass,

and once the bird is in the device,

it can't get out -- there's a perforated metal grill.

NARRATOR: The perforated grill inside the hinged

porthole is key to its purpose.

SOMARA: So once the porthole door is opened,

the surrounding air rushes into that device.

The bird breathes in that air -- if there's something dangerous

in the air, the bird will pass out,

and that's when you know there's something wrong.

NARRATOR: The bird can be saved by shutting

the airtight porthole,

isolating it from the dangerous atmosphere.

And that's where the tank on top comes in.

There's a thin metal pipe that feeds oxygen into the space.

It's airtight, and it's responsible

for resuscitating the bird.

It's almost like a tiny space capsule

keeping that bird alive.

NARRATOR: It seems like an awful lot of

trouble to go to for a small bird.

In reality, this strange contraption is a game changer.

But what is a canary doing inside it in the first place?

NARRATOR: This bizarre life-saving bird box plays

a vital role in the rise of the modern world.

At the end of the 19th century,

heavy industries are sweeping all before them.

MARKS: The world is powered by steam,

and steam, in turn, is powered by coal.

So coal is really fundamental to this new way of life.

NARRATOR: But the more coal the world demands,

the more hazardous coal mines become.

MARKS: It was a really dangerous place to work.

You were at the mercy of cave-ins.

There was big machinery, they were using dynamite,

there were potentially floods.

NARRATOR: But the most feared ways of dying are invisible.

The gases.

All of the toxic gases are called damps,

based after the German word dampf, meaning vapor.

There was almost a superstitious fear with

the damps, because different damps

killed people in different and sinister ways.

NARRATOR: Fire damp, the term used for

trapped flammable gasses, is the most violent

SOMARA: Fire damp is methane,

and you can imagine, these coal miners

were walking around with candle lamps.

Any naked flame would just ignite that methane.

NARRATOR: White damp is a more subtle

but equally deadly killer.

White damp is mostly made up of carbon monoxide.

It's odorless, colorless, tasteless,

and lethal.

STEELE: Every time you're exposed to it,

a bit more of that carbon monoxide

binds to your hemoglobin,

slowly occupying more and more of the slots that are necessary

to carry oxygen around your body.

And if enough of those slots get filled,

you can die within minutes.

It's one of the most dangerous gases in mining,

and one of the most difficult to detect.

NARRATOR: In 1896, 57 men and 80 pit ponies

die in a single incident in Wales.

Oxford physiologist John Haldane is brought in

to investigate.

The bodies show no signs of fatal injuries,

but they do have a familiar pink tinge.

This pink tinge to the skin is one

of the telltale signs of carbon monoxide poisoning.

This demonstrated that it was the white damp,

this silent killer that had killed these men.

NARRATOR: Haldane sets out to find a way

to detect carbon monoxide,

which is where the canaries come in.

But why canaries?

In the late 19th century,

there's no machine capable of detecting carbon monoxide.

But what about an animal?

Physiologist John Haldane locks himself away in his lab,

searching for answers.

He studies mice and quickly discovers they are up

to 20 times more sensitive to carbon monoxide than humans.

Unfortunately, there's a problem with mice.

And that problem is they sleep a lot.

And that means if you see a mouse that's not moving

in its little cage, how do you know

whether it's suffering from carbon monoxide poisoning

or just taking a nap?

NARRATOR: Birds turn out to be much more promising.

They sit on their perch, and if a bird falls off of its perch,

you know it's not sleeping, but it's been overcome.

NARRATOR: And Haldane discovers birds are even

more sensitive to carbon monoxide than mice.

They've got a very advanced respiratory system,

because birds have an incredibly fast metabolism

for one simple reason -- they fly.

And flying expends an absolutely huge amount of energy

per unit weight,

which means they have to inhale huge amounts of oxygen

to power all those chemical reactions

that allow them to stay in the air.

That means they breathe a huge amount more air per unit volume

than a human does,

and are therefore much more susceptible to tiny

concentrations of airborne toxins.

NARRATOR: There are literally thousands of bird species.

So what is so special

about canaries?

Canaries sing, particularly the male birds

are singing almost constantly.

And let's face it, when you're a miner,

you don't have a lot of time to be watching over your bird.

You're too busy mining.

So that means that they might

just notice the canary stops singing.

NARRATOR: Haldane's canaries rapidly transform

the dangerous world of mining.

On February the 15th, 1901, there's a devastating

mining accident in Fife,

and the mine becomes flooded with carbon monoxide.

One of the survivors, Archibald Ramsay,

went back in to rescue other miners,

taking two canaries with him, and afterwards, he said

definitively that it was the canaries who kept him alive.

NARRATOR: This leads to the slightly bizarre

situation of an actual canary law.

MARKS: Haldane's findings about canaries are considered

so important that, by 1911,

they actually pass a law in parliament to say

you must take canaries into the mines, and this isn't

confined to Britain.

Once people realize how vital canaries are,

they become used all over the world as a standard in

coal mining.

NARRATOR: By 1914, canaries are saving the lives

of 800 men a year in Britain alone.

But where does the idea of building

a resuscitator for them come from?

NARRATOR: For the beginning of the 20th century,

the canary resuscitator is a sophisticated piece

of technology.

It is the work of the British engineering company,

Siebe Gorman.

STEELE: Siebe Gorman were a company who specialized in

building diving helmets since the 1830s, and that meant

they knew a lot about the critical technologies to

building the resuscitator --

providing oxygen and air-tight seals.

NARRATOR: And by the time they build this canary resuscitator,

Siebe Gorman have already

developed expertise in this kind of technology.

In 1902,

they actually built a man-sized respirator

for mine rescue, which bought the miner

about two hours working in this toxic environment.

This same technology, now called the Proto,

was also used in World War I for any regions that suffered from

chemical weapons.

NARRATOR: The company's expertise in respiration

and diving is obvious in the construction of the device.

SOMARA: If you look carefully, there are rubber seals on

the panes of glass and the screws

that hold it all together,

but also on the porthole door.

And that's exactly the same kind of technology that's used

in diving equipment.

NARRATOR: This diving technology makes

the resuscitator airtight.

As soon as the miner detected that the bird was in some kind

of distress, the miner would shut the porthole door,

sealing the air inside it.

They then open the valve to the tank,

and all the toxic air would be flushed out,

hopefully saving the bird.

NARRATOR: The black and white paint on the tank indicates

that the contents are pure oxygen rather than simply air,

and that is vital to saving the tiny bird.

STEELE: The higher the concentration of the oxygen,

the easier it is for your lungs,

even if they are in some kind of trouble, to absorb enough to

keep the rest of your body alive.

If you're a canary who's just breathed in a bunch

of toxic gas, then it's far safer

to be in a high oxygen atmosphere,

and that gives you a fighting chance of recovery.

NARRATOR: And on top of the device is a final sign

of Siebe Gorman's expertise.

SOMARA: The oxygen in the tank is highly pressurized,

and you can't let that level of pressure into the device.

It would kill the bird.

So there's a small safety valve that just bleeds

the pressure, making sure that the bird is safe.

NARRATOR: But why go to all this engineering cost

and effort just to save a tiny bird?

[bird chirping]

Some suspect the answer lies in

the relationship between the miners and their canaries.

WEST: I think we should be careful not to underestimate

the need that human beings have,

that lots of animals have, to form relationships

with other things.

We crave connection, we crave interaction.

So if we interact with anything long enough, we have

the potential to form some kind of connection to it.

And if you have a canary in a cage, and it's your canary,

and you're taking care of it every day,

then on some level, your brain becomes attached to

that canary, and you think, well, I love this canary.

This is a very special canary. This is a great canary.

This is my canary.

Perhaps this is the origin of the resuscitator.

It's entirely possible that canary resuscitators

were really a result of the pressure from miners

to protect their friends.

NARRATOR: Canaries become an instant fixture at

the side of coal miners across the world.

But even these much-loved birds

can't survive the march of technology.

By the end of the 1980s,

coal mines everywhere are retiring their canaries.

SOMARA: These birds were used for 100 years down in

the mines, and then they were replaced by little

electronic devices.

NARRATOR: It's the end of the line

for the canary resuscitator.

MARKS: So after a century of saving thousands of lives,

the canary resuscitator ended up being a scuffed object in

a museum, just a historical curiosity.

NARRATOR: The resuscitator may have gone,

but the canaries it protected have left their mark.

MARKS: The memory of the canary in

the coal mine has a long-lasting effect.

After 9/11, canary breeders in New York were not able to

keep up with demand, because people really wanted

that safety of having the canary there

to warn about a potential chemical attack.

And in 2003 in Baghdad, canaries were in

really high demand for the very same reason.

NARRATOR: And they've left their mark on our language, too.

MARKS: Everyone knows what the phrase

canary in the coal mine means.

It's become a shorthand for warning of trouble ahead.

SOMARA: It's incredible to think that that term

that we use so frequently

came from this idea of canaries being so effective

in saving lives.