All language subtitles for How.We.Got.to.Now.S01E02.Time.720p.HDTV.x264-TERRA

Have you ever noticed how
completely dependent we are

on knowing the exact time?

I mean, we take time
for granted now,

but just 150 years ago,
it was all very different.

[ ♪♪♪ ]

Back then, America had
hundreds of towns,

each using its own different
local time.

And 50 railroad companies,
each with its own time.

It was a total nightmare

trying to take a train
around the country.

I mean, you'd have to be
a math major

to figure out
what time it is.

And you could forget about
ever owning a watch

unless you were
incredibly wealthy.

Back in the mid-1800s,
hand-crafted luxury watches

were the only kind
on the market.

So who fixed these problems?

Well, it was a railway clerk
and a cobbler's son.

These are classic examples
of the kind of people

who actually made
the modern world.

People you've probably
never heard of.

[ ♪♪♪ ]

These are hobbyists
and garage inventors.

Woo! Oh, boy.

Maverick characters doing
extraordinary things.

The thing about these pioneers

is that they didn't
just master time,

they also set in motion

an amazing chain reaction
of ideas...

Resulting in innovations
that would go on

to affect every aspect
of our lives.

From how we navigate...

to how we work...

enabling sophisticated
technology...

and time travel into the past.

I want to show how the link

between all these apparently
unconnected worlds

starts with the heroes
of time.

I'm Steven Johnson.

I write about ideas
and innovation.

And this is the untold story
of How We Got to Now.

[ ♪♪♪ ]

How We Got to Now
was made possible in part by

the Corporation for
Public Broadcasting

and by contributions
to your PBS station from...

[ ♪♪♪ ]

Sounding 7-5-8 ballast
to meet the keel.

If you want to completely mess
with your sense of time,

this is the place to come:

the nuclear submarine
USS Asheville.

Steven, third wake-up.
Time to get up.

Most of us, when we wake up
or go to sleep,

we're following the natural cues
of the sun rising or setting.

But on a submarine, when you're
out on the ocean,

underwater for months at a time,

you have none of those cues
available to you.

So people living on
a modern submarine

are as far removed from
the natural rhythms of time

as any human beings
on the planet.

[ ♪♪♪ ]

This submarine is about to
leave port for the next month.

- Up scope!
- Up scope.

The only view Lt. Commander
Jason Deichler will have

of the outside world
is through this periscope.

That's a really clear image,

but, gosh, it would be amazing
to go for like 30 days

and that's your only glimpse
at sunlight.

That's our only glimpse
of topside.

That's our only chance
to ever see the sunlight.

I feel like -- can I just
fulfill a lifelong fantasy here,

- if you don't mind?
- Absolutely.

Here we go,
I'm going to do it.

Dive! Dive!

[ horn blares ]
Oh!

[ ♪♪♪ ]

But the crew aren't just
deprived of the sun.

They've also got six hours
taken out of their day.

Because every day aboard
the USS Asheville

is sped up to the cycle
of an 18-hour clock.

The crew gets six hours
on watch,

six hours on light duties
and recreation,

six hours of sleep,

and then it begins
all over again.

By completely detaching
from sunlight,

the crew's sense of time
can be heavily manipulated.

I have a lot of questions
about this; it's fascinating.

But why you do it?

Well, for us, we have limited
amount of resources

and men onboard the ship,

and it's our way to get through
the day and maintain

the amount of sleep that
you need and rest you need

to stand watch.

And so not only are you guys
breaking from the 24-hour day,

but everybody's on
a different clock, right?

Somebody's nighttime
is somebody's daytime.

Absolutely, and that
shifts continuously

because of the way
the 18-hour clock rotates.

So when a man wakes up,
all he knows is,

"I need to get on watch."

He's not as concerned
if it's light or dark outside,

because we don't get the chance
to see the light or dark

as much as the people
on the surface do.

Those strange surface dwellers.

Yes, the surface dwellers.

We just disrupt everything
that has to do with the clock.

And we kind of become masters
of our own time underway.

[ gulls cawing ]

Most of us would have
a hard time

living on the 18-hour day
so far removed from the sun.

But the truth is,
almost all of us today

are living on artificial clocks
of one form or another.

How did we get so far
out of sync

with the natural rhythms
of the sun?

That's a story
that takes us back

more than five centuries.

[ ♪♪♪ ]

[ bell tolling ]

For millennia, we'd rise
with the sun

and go to bed at dusk.

The very notion of timekeeping
was all pretty relaxed.

I mean, you wouldn't want
to set your watch

by this typical 14th-century
mechanical clock in Tuscany,

which could lose or gain
up to 30 minutes a day.

Back then, timekeeping was
a comically imprecise pursuit.

I mean, a clock like this one
would be corrected

with occasional readings
of a sundial

or sometimes just looking up
at the sky

and making a ballpark guess.

Which meant that every clock
in every town

was telling a different
and irregular time.

But the thing is, no one
really cared back then

because 500 years ago,
the whole idea

of split-second accuracy
in timing

would've been as useful
as a satellite dish.

[ ♪♪♪ ]

[ crows ]

Back then, meeting times
were set

by the movement of the sun,

and time was measured
by the daily tasks

required to work the land.

For example, if I wanted to
arrange a meeting with someone

in 15 minutes' time,
I might say something like,

"I'll see you in the milking
of a cow."

This was all rather vague,
and as a result,

daily schedules
were completely unregulated.

[ ♪♪♪ ]

But our relationship to time
was about to change,

thanks to this guy,
Galileo.

A born rebel, he became
a legend

for proving that the sun,
not the Earth,

was at the center of our
solar system.

But in 1583, he was just
an unknown student

who would discover something
that would forever change

the way we traveled, traded,
and worked.

You ready? Hold it up.
Use all your strength!

Perfect.

- Thank you!
- Sure, sure.

Thank you so much!

Of course, we had a bunch

of professionally trained
cameramen around,

but they asked me to do it.

Most people come to Pisa
for its leaning tower.

Yeah? Oh, my God!
It's really heavy.

But the origins of modern time
as we know it

can be found close by

in the city's magnificent
cathedral.

It's here that Galileo
has an insight

that will revolutionize
how we measure time.

The story goes that it's 1583,
Galileo is 19 years old,

and he attends prayers here
every day.

But one visit,
he gets distracted

by something that most of us
wouldn't even notice:

a swinging altar lamp.

[ ♪♪♪ ]

Highly musical and sensitive
to tempo,

he studies
the rhythmic movement.

Galileo then uses his pulse
as a metronome

to time the swing
of the altar lamp,

and he notices something
unusual.

No matter how far or how short
the lamp swings,

it takes an equal amount of
time to swing back and forth.

This is what I love
about Galileo.

I mean, he's a teenager,
and all the other kids

are dutifully reciting
the Lord's Prayer,

and he's nerding out
on the physics of the pendulum.

[ ♪♪♪ ]

This is what's so critical
to Galileo's contribution

in changing time,
his rebellious nature.

Back then, a good scholar

was supposed to simply quote
existing scientific knowledge,

not investigate it.

But Galileo's more keyed in
to the thrill of discovery

than convention, and he sets up
an experiment

which confirms
his observations.

Galileo writes to a friend,

"The marvelous property
of the pendulum

is that it makes all its
vibrations, large or small,

in equal times."

And it's that discovery,
the idea of equal time,

that will become one of
the foundations of modern life.

This gives Galileo the seed
of an idea,

a hunch that a pendulum's
an important tool

for measurement.

So what happens next?

Well, nothing.

[ ♪♪♪ ]

That's partly because
Galileo is busy

becoming a genius in physics
and mathematics and astronomy,

alienating his academic
colleagues,

and struggling with money.

But this seed won't actually
bear fruit

for almost 60 years,
because right now

no one actually needs
an accurate clock.

And this is the interesting
thing about great ideas:

just like plants,
they often need

the right set of conditions
to flourish.

So this insight is just parked
in a corner

of Galileo's brain.

That is, until a new set
of conditions come along

which, luckily for Galileo,
are backed up

by a whole heap of cash.

[ ♪♪♪ ]

In 1598, King Philip III
of Spain grabs the attention

of every scientist in Europe

by offering a life pension
in ducats

to anyone who can solve

the greatest scientific
challenge of the age:

a way to measure longitude.

Woo! Oh, boy.

Ships in Galileo's day
were sailing blind

over vast new distances

and frequently meeting
with disaster.

[ thunder rumbles ]

For the New World
to be conquered,

something had to be done.

JOHNSON: All right,
so what happens if I try

and actually take the wheel?

Yeah, I'm happy to
give you the wheel.

I have no training
whatsoever.

- No problem.
- Nothing can go wrong.

[ man chuckles ]

- Carry on.
- Thank you.

So I'm piloting or skippering
or something --

I don't even know what I'm doing
with this sailboat,

but I've been given
the instructions here

to follow 060 on the compass,

which I'm kind of managing
to do,

although it's pretty hard.

But the bigger problem is
I have no idea where I am.

So what does any of this
have to do with time?

It was maritime navigation

that would drive the advancement
in our measurement of time.

On land, there's no need
for clocks

that are accurate to the second.

But at sea, in this
Age of Discovery,

sailors are starting
to realize

that accurate measurement of
time is crucial to navigation.

Which means that the need
for accurate clocks

won't come from the calendar,
it will come from the map.

[ ♪♪♪ ]

Navigators can figure out
their latitude --

how far north or south
they are --

by reading the sun.

But to figure out longitude --

how far east or west
they're going --

they need two things:
the local time on the ship

and the exact time
where they left port.

Using the difference between
these two times,

they can calculate their
exact position.

But with no accurate clock
onboard,

they soon end up
completely lost.

[ gull caws ]

I have to get us
back on course here.

[ chuckles ]

[ ♪♪♪ ]

So this challenge, accompanied
by a fat reward,

is looking good to Galileo,

who's now a father of three
illegitimate children.

The memory of the pendulum
is yet to surface,

because by now, Galileo's
completely obsessed

by astronomy and the new
invention of the telescope.

In 1610, he discovers

that Jupiter has its own
orbiting moons

which eclipse in a regular
and predictable way.

He proposes that sailors
use these movements

as a celestial timekeeper
in the sky.

Theoretically,
it's a brilliant idea,

but in practice, bobbing around
in the middle of the ocean,

it's almost impossible to make
precise astronomical readings.

I mean, I'm having a hard enough
time just seeing

that seagull over there,
much less figuring out

what's happening on the moons
of Jupiter.

Okay, so that doesn't work.

But it's this dead end
which finally brings Galileo

back to his original insight

into the equal time
of the pendulum.

Staring at the heavens
reminds him

of gazing up inside
the cathedral,

those swinging altar lamps,

the pendulum experiment
of equal time,

the desperate need
for an accurate timekeeper,

and, bingo, Galileo
finally realizes

that a pendulum could be used
to regulate clocks.

So this is what
he comes up with,

a design for a perfect
swinging pendulum.

Its beats are equal,
and it can be used

to control the hands
of the clock.

It's a revolutionary idea,

but Galileo is now
near the end of his life

and doesn't get the chance
to test it at sea.

This is a classic case

of someone failing to solve
a problem,

but in failing, they hit upon
an even more important idea.

Galileo never wins
any of the longitude prizes,

but he does design

one of the most important
inventions of the age,

the pendulum clock.

[ ♪♪♪ ]

This idea that's taken
decades to come into focus

is now going to have
massive repercussions

for the modern world.

Within 15 years, Dutch
astronomer Christiaan Huygens

produces the first true
pendulum clock.

This technology is now
100 times more precise

than previous clocks,
with the loss or gain cut down

to just one minute a week.

More accurate clocks
also mean better health care.

Now able to record
the passing of seconds,

doctors start using clocks
for the first time

to measure our pulses.

The craft of building
accurate clocks

has another payoff.

Some 100 years later,
Englishman John Harrison

finally solves
the longitude problem

by inventing the marine
chronometer

thanks to ever-evolving
clockmaking expertise.

With better command
of the seas,

maritime trade and exploration
now flourish.

In 1831, a ship sails
to the Galapagos Islands

to fix the longitudes
of foreign lands

with the help
of 22 chronometers.

Onboard is the young
Charles Darwin,

whose findings there
form the basis

of the theory of evolution.

All this evolved thanks
to the pendulum clock,

first imagined by Galileo,

which will continue to be
our best way of measuring time

until the early 20th century.

The pendulum clock
sets a new standard

in the accurate measurement
of time.

But back then, unless you
were a sailor,

you didn't really have
that much need

for minute-by-minute accuracy
in your clocks.

I mean, most people were living
pastoral lives.

They didn't have office
buildings with meetings

or trains and ferries
to catch

and appointments
all through the day.

But then, in the middle
of the 18th century,

something very interesting
begins to happen.

[ ♪♪♪ ]

By the 1760s,
British clockmaking

is among the mt technically
advanced trades in the world.

Craftsmen have devised tools

to make tiny precision-made
parts of gears and screws.

And this expertise is upscaled

to make much bigger,
more sophisticated machines

like steam engines
and mechanical looms.

All of which kick-starts

what is perhaps the biggest
social upheaval ever,

the Industrial Revolution.

Suddenly, our experience
of time changes forever.

People leave the fields
to work in new factories.

They're no longer working
by sunlight

or paid by the task.

Workers must clock in
for the first time en masse

for 14-hour shifts.

They rebel by showing up
late for work.

Factories hire wakers
to rouse them from their sleep

on dark mornings.

[ knock on door ]

The disruption to
our body clocks

gives birth to a major
new trade

in the drugs of tea and coffee
to help us stay awake.

We're now working
on artificial time,

breaking away from a life
that followed the sun.

Time, in the early 1800s,

is still in the hands of those
who can afford it,

giving even more power
to the powerful,

to nation builders
and mill owners

and aristocrats.

And watches were exclusive
status symbols

for the privileged few.

Common people had no hope
of ever owning a watch,

which made it so much harder
for them to gain control

over their own time.

[ ♪♪♪ ]

[♪ ♪ ♪]

The story of how we all
got to wear watches

would have far-reaching and
unexpected consequences,

and change everything
from our moral values

to the way we wage war.

So what are we looking at here?

So this is a very rare piece
called a minute repeater.

I've come to meet
Lawrence Petinelli

at the traditional watchmaker
Patek Philippe

to shop for a watch
19th-century style.

Not to be too indelicate
about this,

but what does one of these
go for?

Well, this particular piece
in rose gold

is $739,000 Swiss francs.

Okay, in dollars?

In dollars, approximately
$750,000

at the current exchange rate.

$750,000, that's worth
more than my arm.

Just as in a 19th-centy
workshop,

these watches are handmade
with exquisite precision,

and they're still
status symbols today.

Look at all these tiny little
intricate pieces

you can see down there.

It's almost like
a little city.

Some of these components
are as small

as the breadth of a human hai.

So they're actually screwing
these things in by hand?

They're screwing them in
by hand.

It doesn't seem phys--
I mean, it feels like

you would have to train fleas
to actually put those screws in.

That's extraordinary.

We're used to it now
in the electronics age

that our world is populated
by all these objects

that have this meticulous,
tiny little mechanical universe

to them that you can only see
through a microscope,

but in the middle
of the 19th century,

a watch like this
would've been

really the only object
in our lives

that would have that level
of precision engineering to it.

It would've been a real object
of wonder.

I've also carved my initials
into this one.

No one will ever know.

Today you don't have
to spend a fortune

to buy a watch.

You can pick one up on the
street for a couple of bucks.

But back in the mid-1800s,
handcrafted luxury watches

were the only kind
on the market.

[ ♪♪♪ ]

The next leap forward in time
and who could own it

would come to us
thanks to this guy,

Aaron Dennison, a man
so obsessed with his vision

that he defied public opinion,
earning himself

a local reputation as a madma.

But Dennison's no killer,
nor is he insane.

He's an ideas man.

[ woman screams ]

In 1826, the 14-year-old
Dennison was working

in his father's cobbler shop.

And he sees his dad
painstakingly custom-making

leather soles
for each individual.

And so one day he says
to his father,

"Why don't we make a batch
of leather soles all at once

for popular sizes?"

And this ends up saving
his father a lot of time,

but the usefulness
of Dennison's idea

won't end there.

[ ♪♪♪ ]

Dennison can't help but hatch
new business ideas.

Age 27, he's got his own
watch shop.

He gets firsthand insight

into this laborious
boutique industry

where many different people
hand-produce

many different parts
to make a single watch.

People are convinced
this is the only way to do it.

In 1840, he causes a storm
of controversy

by predicting that
in 10 years' time,

watches will be made
by machinery.

The public pours scorn
on the idea.

One magazine goes so far
as to call him

"the lunatic of Boston."

[ ♪♪♪ ]

But as with Galileo,
Dennison can't drive progress

by simply accepting
conventional wisdom.

In the face of ridicule,
he sticks to his vision.

Visiting a nearby armory
in Springfield, Massachusetts,

Dennison sees that
the weapons industry

is making guns faster
and cheaper

by producing interchangeable
parts --

that is, identical parts made
in batches by machines.

Now a hunch from
his father's shoe shop

and the experience
of clockmakers

and his observations
of the rifle industry

all start to morph together
into the beginnings

of a commercial plan.

Dennison is going to make
machines

that can produce
interchangeable parts

so that he can mass-produce
watches all under one roof.

Dennison's
revolutionary idea

is to help millions of people
afford something

they could only dream of.

After finding investors,
Dennison builds

this huge factory
in Waltham, Massachusetts.

It's a tremendous operation.

It's filled with nearly
100 employees

operating complex machinery.

It's the first production line
for manufacturing watches.

Mass-producing the relatively
large parts for guns

is one thing, but it's
completely new territory

to mass-produce components
the size of a flea for watches.

New machines need to be
invented to pull it off,

and this doesn't come cheap.

Despite glimmers of hope,
Dennison and his team

are constantly going back
to the drawing board.

But Dennison's like a dog
with a bone.

He's so obsessed
with this idea

that he runs out of money,
has to sell his factory

and suffer the indignity
of returning as an employee.

But ironically, Dennison's
about to be rescued

from his personal crisis
by a crisis unfolding

on the national level.

[ ♪♪♪ ]

The outbreak of the Civil War
brings Dennison

a new business idea.

Despite being ordered
by his new boss

not to pursue any new projects,
what does this crazy guy do?

He waits until the boss
is away on a honeymoon

and orders work
on another watch,

a cheap model
with a patriotic name

that could be marketed
to a captive audience

with time on their hands.

And this is what they produce,

a simple, inexpensive watch
targeted at soldiers

and named after
one of the signers

of the Declaration of
Independence, William Ellery.

It's a steal at $13,

and a fraction of previous
watch prices.

The so-called "soldier's watc"

accounts for 45%
of Dennison's sales.

The Ellery watch is
a breakout hit.

Over 160,000 of them are sold,
an unprecedented amount.

Even Abraham Lincoln has one.

Dennison has democratized time.

In just two decades, watches
become 10 times cheaper,

making them affordable
to a mass market.

The watch becomes the first
must-have high-tech gadget.

[ ♪♪♪ ]

Thanks to a crazy idea,
a transformation

in how we experience time
now takes place.

With more and more people
carrying watches,

we start to synchronize
our actions.

Before wide access
to timekeepers,

battles were started by the
unreliable boom of a cannon.

The Civil War Battle
of Vicksburg in 1863

is the first ever initiated by
the synchronization of watches.

This forever changes
the way we fight.

Watch ownership spurs
an obsession with punctuality.

It becomes a social virtue
to keep good time,

and people buy watches
for their children

to enhance their chances
in life.

Cookbooks evolve from
never using time references

to now offering recipes
with timed instructions.

Team sports start to form
national leagues,

which run on much stricter
schedules,

allowing masses of people
to attend at a fixed hour.

[ cheering
and referee whistles ]

Time gives us the power
to organize

and improve the effiency
of our lives,

but there's a deep irony here,

because the more we start to own
our own time,

the more time starts to own us.

We can finely tune
our schedules,

but we're constantly worrying
about them

and getting anxious about
being late.

So not only do watches
liberate us,

but they also start
to enslave us.

But 130 years ago,
there were other consequences

of us all owning watches.

As more and more people
in the 19th century

can own a watch and synchronize
their activities,

it slowly dawns on society that
it's not just groups of people

but whole nations that need
to get on the same clock.

[ engine roars ]

Spirit 856, contact London
on 118.825.

Hold short 2-7 left,
contact tower channel 11.

This is Heathrow Airport,

which transports more
international passengers

than any other airport
in the world.

Turn right at taxiway alpha,
holding point at saturn.

The people in the air traffic
control center

coordinate over 1,300 flights
a day

with planes landing and taking
off every 45 seconds.

[ engines roaring ]

It's a miracle of scheduling,

and now I'm going to have
a go at it.

Not for real,
but in their simulator

with trainer David Marshall.

Just like in the real tower,

the most important piece
of equipment in the whole room

is the simple, everyday clock.

Every second counts
as a departure controller.

If you can save two seconds
per airplane per hour,

it would mean an extra two
or three departures an hour.

That can be as many
as 1,000 people.

So I probably shouldn't
check Facebook

while I'm in the middle of this
on the screen here.

I should just really
stay focused on the job.

Okay. All right.

He's already on the roll,

he's already moving around
the corner,

so we can say -- and you're
going to say it, Steven --

"Turkey Five Hotel Mike,
line up 091."

[ exhales sharply
and laughs ]

Okay, so I'm not a natural.

He's going out to the east.

We've got this guy who's got
to turn to the west.

- There's our first lander.
- I'm already really confused.

If we look out --

Yeah, I can see them moving.
That's pretty cool.

Every single landing
and takeoff

is recorded to the second.

When he gets airborne, as soon
as his nose wheel comes up,

you hit that button there.

Planes are converging
at Heathrow

from 180 different
destinations.

So it's pretty important
that they're all using

one standard time.

Every air traffic clock
is in Greenwich Mean Time.

Every air traffic clock
in the world?

All over the world, we're all
working on the same time.

Okay, we've now wasted
20 seconds.

He could've been airborne
20 seconds ago.

Sorry!

So how did we get to a global
system of standardized time?

[ engine chugging
and steam hissing ]

[ bell ringing ]

Well, it was all thanks to
an egomaniacal railroad clerk

150 years ago,

a man who went head-to-head
with public opinion

to help launch a new dawn

for telecommunications
and broadcasting.

[ bell ringing ]

In the middle of
the 19th century,

the railroad is transforming
America.

In just a few decades,

over 100,000 miles of track
are built,

connecting the continent
for the first time.

It's an heroic chapter
in American history,

but it creates
an unexpected problem.

[ ♪♪♪ ]

Here's the issue.

The railroads are connecting
all of these towns

that have historically
maintained

their own individual time set
by a local reading of the sun.

In the 1880s, there were
hundreds of towns,

each using its own
local time,

each differing not by the hour,
but by the minute.

There were 23 different times
in Indiana,

27 in Michigan,
and 38 across Wisconsin.

What makes it even worse
is that

in addition to each town
having its own time,

each railroad had its own time.

And there were 50 different
railroads.

[ steam whistle blowing ]

So back then, taking a journey
by rail

was something of an adventure
which could leave you

more than a little confused.

So you know what it's like
taking a train ride today.

You can kick back, read a book,
listen to some music.

But imagine what it would've
been like in 1870,

trying to take a train.

Let's say we're traveling
from New Haven to New York.

And so I get on the train
at 12:00 New Haven time,

and it takes us two hours
to get to New York.

So we should be arriving
in New York at 2:00,

but in fact, in New York time,
that's technically 1:55.

But the train we're on
is actually running

on Boston time, so that ans

we're actually pulling into
the station in New York

on Boston time at 2:17,

but then we're like making
a connection

to a train to Baltimore that's
running on Baltimore time,

so that train is actually
leaving the station

at 2:07, which seems to be
in the past.

I mean, you have to be
a math major to figure out

what time it is!

[ ticking grows louder
and louder ]

If you think that was confusing
for the individual passenger,

imagine what it was like
for this guy,

William Allen, who was secretary
of the General Time Convention,

which meant that he was
in charge

of reconciling the rail
timetables

for the entire U.S. system.

[ ♪♪♪ ]

Most people would run away from
this mathematical nightmare,

but Allen seems mysteriously
drawn to it.

Professor Alexis McCrossen can
shed some light the matter.

What really motivates Allen
to get involved

in the reinvention of time,
basically?

First and foremost,
he's opportunistic.

He is an egomaniac.

And this is his opportunity
to make a name for himself.

Allen realizes that
his path to greatness

is in managing the schedules
of all of these railroads

that are proliferating like
mushrooms after a rainstorm.

I like that idea
of the path to greatness

being publishing
railroad timetables.

That's -- "I'll be famous
beyond imagination!"

"Timetables, that's it!"

But it's 1881, and Allen
seizes the moment.

And what he does is
he introduces the idea

of time zones.

So not just of standardizing
the time,

not just of creating
one railroad time

that all the railroads
would follow,

but of dividing the standard
time in the United States

into four zones.

So this is the original map
that Allen actually drew.

I mean, this is kind of
the blueprint

for the time zone system,
right?

I mean, he actually
hand-colored

these different divisions?

Yep. Yep.

He figured out where to divide
the time zones,

and he divided them
at the basis of where

different railroad lines
ended,

where they're terminated.

And so he didn't exactly
follow state lines,

but he followed the geography
of the railroad.

[ ♪♪♪ ]

Allen has a major fight
on his hands,

because the proposal
of standard time

is a deeply controversial ide,

and many Americans
are afraid of it.

[ alarm ringing ]

Allen starts an enormous
lobbying campaign,

writing nearly 600 letters
and countless circulars

to mayors and city councils

to try to cajole and arm-twist
them into signing up.

But there's fierce opposition
to the prospect of change.

A paper in Cincinnati writes,
"It's simply preposterous!

Let the people of Cincinnati
stick to the truth

as it is written by
the sun, moon, and stars."

And these are all the original
circulars that he sent out.

Look how many of them
there are!

- Oh, hundreds.
- It's amazing.

"Are you in favor of the hour
system of time standards

as illustrated by
the accompanying map?"

And you've got this great
kind of 19th-century "Yes!"

But some people -- this guy,
he answers, "I think not."

That's right.

And check this out, then he
writes on the back why.

He says, "Dear sir,
the reason why I say no

to the questions
on the other side of the sheet

is because it would be
an entire revolution

in our time."

I mean, that's it.
It's a revolution in our time.

That's what he's trying
to put in motion.

[ ♪♪♪ ]

After an epic seven-month
battle

to wrestle America's
chaos of times

into a simple system,
Allen finally triumphs.

All of which leads to
one of the strangest days

in the history of time,
November 18, 1883,

the day of two noons.

[ bell tolling ]

The first noon rings out
at St. Paul's

in the New York local time.

And then, four minutes later,
there's another noon,

the first ever 12:00 p.m.
Eastern Standard Time,

announced by the bells
of Trinity Church.

[ bells ring in descending
scale ]

[ ♪♪♪ ]

As the bells ring out,
the new standard time

is sent down the telegraph
lines

for all the railroad stations
to set their clocks to.

America goes from hundreds
of times to just four.

And rail travel becomes
a hell of a lot easier.

Just a few weeks after his
time system is implemented,

Allen writes in a letter,

"The adoption of the standard
time system

is an event which is likely
to be noted

in the history of the world
for all time."

I mean, okay, it may sound like
he was a little full of himself,

but actually, he might've had
a point.

Because if you think about it,
it's not just railroads.

Any time you take a flight
somewhere

or schedule a phone call
with somebody

living in another city,

you're living inside of
standardized time.

Thanks to Allen's
dogged crusade,

America becomes a modern
nation by embracing

one single system of time.

[ ♪♪♪ ]

The very next year,
Greenwich Mean Time

is set up as the
international meridian,

and the whole world is divided
up into time zones.

With this new web of time
wrapped around the world,

we are now more closely
connected to foreign countries

through improved trade, travel,
and communications.

We also become clor
to our fellow citizens

through broadcasting.

Now, for the first time ever,
millions of us

could sit down to a show
at exactly the same moment.

ANNOUNCER: Tonight,
in the deciding game

of the Eastern League
baseball pennant race...

The story of time in the
20th century is all about clocks

shaving the second down to
smaller and smaller increments.

And some of these tiny clocks

are inside our laptops
and our cell phones.

It turns out you can't make
a computer

without a super accurate clock.

And all of these devices
together combine

to speed up our lives
in a thousand different ways.

And that's the funny thing
about modern clocks.

The better we get
at measuring time,

the less we seem
to have of it.

But the most important change
in our measurement of time

would come from a scientific
breakthrough

that had both catastrophic
and transformative consequences

for the entire world.

[ loud explosion ]

[ ♪♪♪ ]

Atomic physics brings us
man's most destructive weapon.

But it also provides us
with a platform,

an environment that encourages
people to think big,

bringing revolutionary ideas
to energy and medicine.

This pioneering work in physis

will transform our relationship
to time,

revealing secrets about
our ancient past

and also helping us predict
our future.

In October of 1967,

a group of scientists gathered
in Paris

and changed the very definition
of time itself.

They decided that
the astronomical time

that humans had used
for all of history

simply wasn't accurate enough
anymore.

And they decided to trade

the largest object
in the solar system

for one of the smallest,

and we entered the age
of atomic time.

[ ♪♪♪ ]

You could say that time
as we know it

is largely thanks
to this place,

the U.S. Naval Observatory
in Washington, D.C.

This building has a name
that sounds like something

out of a George Orwell novel:
the Directorate of Te.

These are some of the
most accurate clocks

that human beings
have ever designed?

Yes.

You might think that the clocs
we use are still ultimately st

by the rotation of the Earth,
but in fact,

today we measure time by
tracking the behavior of atoms

using atomic clocks
like these.

The man in charge here

is time lord
Dr. Demetrius Matsakis.

He's got some insane
statistics.

How do we define a second now?

A second is defined as

9,192,671,770 periods
of oscillation

of an undisturbed
cesium atom.

[ laughs ]

That's... I hope all the
schoolkids have memorized that.

[ ♪♪♪ ]

Just like a pendulum,
atoms can be used

to measure equal intervals
of time

by reading the regular pulses
of energy they emit.

These are the most accurate
measurement system

ever made operationally
by mankind.

In terms of measuring
anything.

In measuring anything.

A good cesium clock
on a bad day

will differ by about
5 nanoseconds

in its time from what
we thought it would be.

So a nanosecond is one...?

- A billionth of a second.
- One billionth of a second.

The thing is, when the first
atomic clocks

were built in the 1950s,

their formidable power
to break down the second

confirmed something
extraordinary:

the Earth's rotation
is slowing down.

Back when T. Rex roamed
the world,

a day was only 23 hours long.

And ever since, the solar day

has been slowly ineasing
in length.

Not only that, atomic time
also showed us

that the Earth's rotation
is not always consistent.

To compensate, a leap second
was added to the clock.

But this intervention into tie

has been a little
controversial.

The leap second argument
is that some people think

we don't need
this extra second.

That's right.
They think that adding --

including that second
is too disruptive.

There are many stories
about web pages going down,

airlines having to shut down

because their computers
went offline

when they detected
a one-second jump

and didn't know
it was coming.

That shows you how dependent
the world has become

on this level of accuracy
in timekeeping.

You tell a computer,

"Oh, there's an extra second
in this day,"

and an entire airline system
goes down.

Yes, that could happen.

You probably won't have
noticed, but since 1972,

25 leap seconds have been
added to our lives.

Once these clocks have ordained
what time it is,

an intelligent average,
the Universal Standard Time,

is then distributed
by this monster clock.

This is where U.S. standard time
is broadcast out

to the entire country.

Every time you check your phone
to see what time it is,

you're ultimately getting
that information

from this clock in this room.

I mean, it's actually
kind of bizarre

that I'm standing right
next to it.

I feel like I could
kind of fiddle

with some of these buttons
and, like,

the entire country would be
late for work.

Atomic clocks are now
so accurate

that we can measure time
with a drift

of just a single second
every -- wait for it --

5 billion years.

And increasingly, these clocks
are important

not just for finding out
what time it is,

but for finding out
where we are.

That's because every time
you look at your smartphone

to assess your location,

you're calling on ultra precise
atomic time.

So let's say I'm in a big city,
and I want to find out

where the nearest
coffee shop is.

I take out my phone,
and up above me

there are 24 GPS satellites,

and they're effectively
giant clocks in orbit,

only they're accurate
to a billionth of a second.

My phone gets a signal
from four of them

that's basically just sending
a time stamp,

only there's a slight difference
between each of the signals.

Using those differences in time,
my phone can calculate

its exact distance
from each of the satellites,

enabling it to fix its location
with pinpoint accuracy.

But GPS satellites do way more
than just get us from A to B.

For starters, their clocks
coordinate the system

used by cash machines and other
financial transactions.

GPS gives us cheaper food
thanks to robotic farming.

Not to mention all the GPS apps
that help us

peer around the corner
to hail a taxi

or figure out when the next
bus is coming

or even to find the nearest
coffee shop.

It's incredible to think
about it,

but all this GPS technology
is ultimately dependent

on electrons dancing
around an atom.

But atomic physics would
usher in another revolution

in our measurement of time.

This one wouldn't tell us
where we need to go,

buinstead where
we've come from.

[ ♪♪♪ ]

This is about as far
from the modern world of time

as you can get.

I'm in California's
Anza-Barrego Desert,

and looking out here, I can't
see any sign of civilization.

And the whole contemporary
rhythm of split seconds

is just almost impossible
to imagine.

Here, you're living
on geologic time.

[ ♪♪♪ ]

This is where,
millions of years ago,

the notorious San Andreas Fault
was created

in southern California.

It's a barren and beautiful
landscape,

but before this, it was a lush
savannah with rivers and lakes

populated by exotic animals --
saber-toothed cats and mammoths.

And before that, it was
a vast ocean

teeming with aquatic life.

So how do we know this story?

Well, in part because
we invented

a very different kind of clock.

For centuries, we had no idea

exactly when the first humans
spread across the globe

or exactly how to date
the rich source of fossils

scattered all over
the desert floor.

[ ♪♪♪ ]

That is, until this brilliant
woman came along,

Marie Curie.

In the 1890s, she made history
by studying the new field

of radioactivity.

She and her husband, Pierre,
showed the world

that radioactive atoms
decay at constant rates.

Carbon 14, for example,
decays by 50%

every 5,730 years.

Other elements have wildly
different rates of decay,

but each one is regular
and predictable.

Once again, science had
delivered the crucial concept

of equal intervals of time,

and the idea dawned that rocks
could be clocks.

Clocks that don't tick
by the second,

but on the scale of centuries
or millennia

and deep into the past.

So there was -- basically,
above a certain point here,

there was an ocean.

Yes, about 6.25 million
years ago.

Paleontologist Lyndon Murray
uses radiometric dating

to read the landscape.

It has an error margin
of just 2-5%.

I guess there's a basic
question of why do we do this?

The geology and dating
of what happened here

can help in determining
a record of past climate

of 8 million years,
actually.

So we can see a sequence
of events

that happens and how
and perhaps why

the climate changes.

So in a way, all these
technologies

that let us look back into
the past with such precision

are actually also enabling us
to predict the future.

Yeah. Yeah.
I've always thought that.

[ ♪♪♪ ]

Radiometric clocks have given us
this amazing time machine.

I mean, they've helped us
pinpoint

exactly when humans first
crossed the Siberian land bridge

into the Americas.

But they've also helped us
predict the future.

And in doing that, they may
help us tackle

one of the 21st century's
most important problems,

how to solve climate change.

So in a way, clocks aren't just
about measuring time.

They can also help us understand
where we came from

and where we're headed.

In the 400 years
that have passed

since Galileo first started
tinkering

with the equal time
of the pendulum,

clocks have transformed
just about every facet

of modern life.

And there are those who say

that our modern, accelerated,
sped-up world

is too frenetic,

and they long for the slower
pace of a pastoral life

when our clocks were set

by the rising and the setting
of the sun.

But the thing about
the modern clock

is that it's never just been
about time.

In a very real sense,
our ability to measure time

in increasingly small increments
has made the world

a smaller and more connected
place.

As to what the clocks
of the future will bring us,

for that, only time will tell.

In the next episode,
I'm exploring how glass

is instrumental in science's
greatest revolutions.

From a physics teacher
who fires crossbows...

The strange physical properties
of glass

would open up a whole new world
of possibilities.

to the man on the moon,

glass has changed the way
we view and share

our world today.