The Mystery of Matter: Search for the Elements (2015–…): Season 1, Episode 1 - Out of Thin Air - full transcript
One of science's great odd couples--British minister Joseph Priestley and French tax administrator Antoine Lavoisier--together discover a fantastic new gas called oxygen, overturning the reigning theory of chemistry and triggering a worldwide search for new elements. Soon caught up in the hunt is science's first great showman, a precocious British chemist named Humphry Davy, who dazzles London audiences with his lectures, introduces them to laughing gas, and turns the battery into a powerful tool in the search for new elements.
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One night in 1669, a German
alchemist named Hennig Brandt
was searching, as he did every
night, for a way to make gold.
For some time, Brandt had
focused his research on urine.
He was certain the "golden
stream" held the key.
Tonight, his patience
would at last be rewarded.
He had boiled the urine down
to a concentrated paste.
Now he subjected it
to intense heat.
Was this the legendary elixir
that would turn lead into gold?
Alas, it was not.
Brandt had stumbled
on the element phosphorus.
This is how the discovery
of elements began:
with people trying to turn
the substances of nature
into something useful
or valuable.
But people
are naturally curious,
so as they worked
with these materials,
they began to wonder,
"What is this stuff?
What is the world made of?"
Thousands of years ago, the
Greeks proposed that the world
is actually made of just
four elements in combination:
air, water, earth and fire.
Today, we know that matter
actually comes in more than
a hundred distinct varieties,
neatly arranged in the periodic
table of the elements.
But for most of history,
matter was a profound mystery,
a 2,000-year detective story
in which people across the world
were trying to identify
the elements
and figure out how to use them.
It's an amazing story, filled
with unforgettable characters.
In this series, you'll meet
seven extraordinary scientists
whose findings drove the search
for the elements.
So join me
as we retrace the steps
of these chemical detectives
as they struggle to solve
the mystery of matter.
*
One of the first big clues
in solving the mystery of matter
came from the discovery
of the most immaterial stuff
you can imagine: air.
Of course, people have always
known about air.
They could feel the wind
on their faces
and see its powerful effects
in storms.
What they didn't know
was that there's more
than one kind of air.
That changed in 1754,
when a young Scottish medical
student named Joseph Black
set out to find a cure
for kidney stones.
He poured acid
on this chalky substance...
...and trapped the air
that came out.
To his surprise, this "air"
didn't behave like air at all.
It was heavier than ordinary air
and promptly put out a flame.
Black's discovery of fixed air--
what we now call
carbon dioxide--
was a turning point
in the history of science.
People had long known
about liquids and solids.
Now suddenly, they realized
there was a third state
of matter-- gases--
of which air
is just one example.
Over the next 20 years,
the exploration
of this new dimension
would transform
our understanding of matter.
After Black's discovery,
British scientists quickly
identified two more new gases:
hydrogen and nitrogen.
And then in the early 1770s,
that astonishing investigator
Joseph Priestley
discovers all sorts of new airs.
Priestley was a minister
by trade,
but also an amateur scientist--
what was then called
a natural philosopher.
He was a great dabbler in things
and was constantly getting
obsessed with new fields.
Fields like the new science
of gases.
Priestley's style of science
is very interesting.
He's a kind of inspired forager.
He's basically messing around
with different things
to see what will happen.
One of the things Priestley did
was to pour acid on everything.
He collected those bubbles,
tested them thoroughly
and discovered all sorts
of amazing properties.
By "messing around" in this way,
Priestley discovered
nine new gases--
more than anyone else
in the world.
He was very much open
to chance discoveries.
He would stumble across things
and he would follow
his instincts.
And he was always looking
for these kind of fortuitous
accidents.
One such accident happened
in 1767,
when Priestley was assigned
a new congregation.
They put him in a house
that happens to be right next
to a brewery.
And this turns out to be an
incredible stroke of good luck.
Priestley, being the constant
investigator that he was,
would kind of pop over
and see what was going on
at this brewery.
Just above the vats of beer,
he discovered a haze
of carbon dioxide
bubbling up
from the fermenting brew.
And he decided he wanted to do
some experiments
with their beer.
Well, fortunately,
they said yes.
Priestley found that
if he simply poured water
from one glass to another
over the surface,
the water would absorb the gas
rising from the beer.
The result was
refreshingly bubbly.
By 1772, he had invented
a better method:
generating carbon dioxide
and injecting it directly
into water.
In the space of two
or three minutes,
I can make a glass
of exceedingly pleasant
sparkling water.
You can't tell the difference
between this
and natural mineral water.
Priestley had invented
carbonation.
Remember that the next time
you enjoy a soft drink.
But with this act,
he also set in motion
a series of improbable events
that would soon overturn
our understanding of matter.
It began when a British doctor
suggested Priestley's
"windy water"
might be effective
as a treatment for scurvy,
a disease that plagued sailors
on long sea voyages.
Scurvy was a huge problem for
the military during that period,
and so the idea that there was
this potential solution
that also happened to be
a tasty beverage was appealing.
In 1772, Priestley addressed
Britain's leading scientific
organization, the Royal Society,
and published a pamphlet
describing his method
for making soda water.
He urged the British navy
to test the potential cure.
Quick to pick up
on this development
was a defrocked Portuguese monk
named João Jacinto de Magellan.
A distant relative of the great
Portuguese navigator,
he was now serving
as a French industrial spy.
Magellan is in the employ
of the French government
and is there basically
scouting out the Royal Society
for interesting items
that he might be able
to bring back to his bosses.
Sensing a potential
military secret,
Magellan alerted his handler
back in France:
Commerce Minister Jean Charles
Trudaine de Montigny.
Trudaine was interested
in science,
was a member of the French
Royal Academy of Sciences,
and immediately saw
the possible value of this.
Trudaine, in turn,
called on one of France's
brightest young chemists,
Antoine Laurent Lavoisier.
"I know your precision when it
comes to physics and chemistry,
"and I'm giving you a chance to
be of service to your country.
"Please repeat these experiments
and add your own observations.
The value of these discoveries
depends on our moving quickly."
I hope you will not be long in
getting this little work done.
Trudaine probably intended
this politely phrased letter
as an order
rather than a request.
Lavoisier really couldn't
ignore it.
Though soda water would turn out
to be useless against scurvy,
this pointed suggestion
by a government official,
acting on a tip
from a Portuguese spy,
would set Lavoisier on the path
toward his greatest discoveries.
Born into a well-to-do
Parisian family,
Lavoisier had received
a fine education
and taken a degree in law.
Now 28, he had joined
a consortium
that collected taxes
for King Louis XV.
As a result, Lavoisier became
a very wealthy man.
But his true passion
was chemistry.
Lavoisier spent three hours
in his private laboratory
before work every day
and returned there after dinner,
often accompanied
by his young wife.
Marie-Anne Paulze
was the daughter
of one of Lavoisier's
business partners.
She was just 13
when they were married,
but bright, outgoing and mature
beyond her years.
Marie-Anne was virtually
his collaborator.
She knew English,
learned chemistry,
assisted Lavoisier
in the laboratory.
She was an extraordinary person.
Had she lived in our own time,
she probably would have become
an outstanding scientist
in her own right.
One of Marie-Anne's
most important roles
was to create the diagrams
and illustrations
that accompanied her husband's
published work.
Marie Lavoisier's drawings
give us the eyes
to look directly
into Lavoisier's laboratory.
We can see the people.
We can see the devices.
We can see the arrangement
of those devices.
We can understand
what Lavoisier did
so much better
because of what Marie drew.
Spurred on by Trudaine,
Lavoisier eagerly studied
fresh translations
of Black, Priestley
and the other British chemists
who had pioneered
the study of "airs."
The work of these previous
experimenters
merely hints at what's happening
when air is taken up or released
by different substances.
I shall review all their work,
repeat all their experiments,
taking new precautions,
in order to develop
a coherent theory.
This subject, I believe,
is destined to bring about
a revolution in physics
and chemistry.
What made this new science
of air so revolutionary
was that it threatened to topple
the reigning theory
of chemistry,
a theory inspired
by the mystery of fire.
Most chemists believed fire
was due to some fiery principle
that was given up
during combustion.
And all our senses
seem to confirm this idea.
Heat, light, smoke-- all are
released as the fire burns.
By the mid-1700s,
this essence of fire had been
given a name: phlogiston.
Phlogiston was the foundation
of chemistry's leading theory
for nearly a century,
because it seemed to explain
things like metals and rust.
When iron ore was heated
in the presence of charcoal,
phlogiston from the charcoal
fused with the ore
to form metallic iron.
When the iron was exposed
to air or water,
the metal released
its phlogiston as it rusted.
Other metals went
through the same process,
forming the green verdigris
of copper, for example.
Ore plus phlogiston
equals metal.
Metal minus phlogiston
equals rust,
or what was then called
a "calx."
Only there was a problem:
the calx was heavier
than the metal,
even though phlogiston
had left the metal.
It's lost something,
and yet it was heavier.
The calx should weigh less
than the original metal,
but it doesn't.
The calx is heavier
than the metal.
Though many chemists were aware
of this contradiction,
they let it pass
because phlogiston otherwise
worked so well.
But Lavoisier
was really troubled by this
because he was obsessed
with the weights
of his experimental ingredients.
Lavoisier was very careful
to get very good instruments.
He probably at one point
had the largest
and most complete
private laboratory on earth.
With my precision scales,
imported from England
at great expense,
I measure the weight
of each substance
at the beginning and end
of every chemical reaction.
Lavoisier was a master of this
balance sheet kind of chemistry.
Remember, he was
a tax administrator by day.
He knew a lot about accounting.
And so this kind
of ledger-keeping
was natural to him.
It is a fundamental truth
of chemistry
that the same amount
of matter exists
before and after
each experiment.
Nothing new is created,
nothing lost.
The whole art of performing
chemical experiments
rests on this principle.
Today, we call this idea
the conservation of matter.
When you carry out
a chemical reaction,
what comes out has to be
exactly equal to what goes in.
The total weight must remain
precisely the same.
If not,
there's an error somewhere.
He wasn't the first to assume
conservation of matter,
but Lavoisier applied this idea
more rigorously
than anyone had before.
And it worked very effectively
as a tool: a tool of discovery.
The power of Lavoisier's method
would become clear
in October 1772, when he set out
to solve the riddle
of why metals gain weight
when they form calxes.
Common sense suggested
that when things rust,
they must lose weight.
They fall apart.
They become brittle and weak.
Lavoisier was interested
in actually measuring
what happened.
He conducted his experiments
in public,
relying on a huge burning lens
that focused the sun's rays
to produce intense heat,
while elegantly dressed
bystanders watched in amazement.
Lavoisier placed a calx of lead,
mixed with charcoal,
inside a glass vessel
partially filled with water,
then subjected it to the intense
heat of the burning lens.
The result was extraordinary.
As the calx changes
back into the metal,
it releases a large quantity
of air.
This air forms a volume
1,000 times greater
than the calx it came from.
This startling finding suggested
a radical idea.
If air came out as the calx
changed back into a metal,
could it have gone in
when the calx was formed?
Could air be the reason calxes
were heavier than expected?
Lavoisier also found that when
he burned elements like sulfur,
they, too, gained weight.
There was then no doubt.
I realized that the increase
in weight occurs
because a portion of the air
is absorbed
into the solid material.
He knew he was onto something
very important.
He knew that the element
did not lose mass;
it gained mass.
It took up some part of the air.
I felt I must secure my right
to this important discovery.
So I deposited a note
with le Secretaire de l'Academy
to remain sealed
until I was ready
to make my experiments public.
He's discovered
what seems to be evidence
by weighing things
that seem to flatly contradict
what the phlogiston theory
is predicting.
Despite what our senses tell us,
both rusting and burning
involve absorbing something
from the air--
just the opposite
of what chemistry's
reigning theory held.
It had been known for 100 years
that metals gain weight
when they become calxes,
but no one had bothered to
really investigate this anomaly.
By focusing so intently
on weight,
Lavoisier had challenged the
very foundation of chemistry.
And he'd identified the source
of that weight gain.
Air was somehow involved.
But was it air itself,
or some part of the air?
And if so, what part?
The identity of the mystery gas
eluded him for two years.
He was still stumped
in late 1774.
But the answer
would soon be delivered
by Joseph Priestley.
By this time, Priestley had
begun to study something
called the red calx of mercury.
Mercury is a strange metal,
one of just two elements that is
liquid at room temperature.
But like other metals,
it forms a calx,
a red solid that pharmacists
of the 1700s used
to treat venereal disease.
Chemists had noticed something
unusual about this calx.
They could convert it
back into metallic mercury
simply by heating it.
No charcoal--
no source of phlogiston--
was needed.
This was theoretically
impossible.
How could it be?
The ever-curious Priestley
wanted to know,
so in August 1774, he obtained
a sample of mercury calx
and used his own burning lens
to heat it with sunlight.
That reddish substance
in turn decomposes,
giving back mercury,
but also a gas.
Priestley collects this air
because he likes
to test these gases
to see what properties
they have.
If it were his old friend
"fixed air,"
the candle would go out.
But what he found
about this air
was that it had quite
extraordinary properties.
What astounded me was that
the candle burned in this air
with remarkable vigor.
The flame was bigger and
brighter than in ordinary air.
Something in this air seems
almost better than normal air,
which is very puzzling.
I was utterly at a loss.
How could I explain this?
Dr. Priestley, have you been
to the Continent before?
No, this is my first time.
Two months later,
on a visit to Paris,
Priestley was invited to dine
with members
of the Royal Academy
of Sciences,
including Antoine Lavoisier.
J'ai récemment réalisé...
Priestley tells Lavoisier
in his very broken French
about his new discovery.
...avec les résultats
tres intéressants.
I described this experiment
at the table
of Monsieur Lavoisier.
I never make the least secret
of anything I do.
...la meme aire
de plombe rouge.
Everything that he came up with,
every new experiment
that he did,
even when he wasn't sure
what the results meant...
Qu'est-ce que c'est
ce plombe rouge?
...he was constantly
sharing that information
with as many people as possible.
Mais à ma grande surprise...
I also told them that
it produced a kind of air
in which a candle burned much
better than in common air.
...mieux que dans l'air commun.
At this, the entire company,
including Monsieur
and Madame Lavoisier,
expressed great surprise.
I'm sure they cannot have
forgotten these events.
Monsieur Priestley,
etes-vous bien sûr que
ce n'était pas l'air fixe?
If you want,
I can translate for you.
Merci.
Are you sure that what you found
was not fixed air?
Absolutely.
But I'm not yet sure
of what it was.
Lavoisier did not appreciate
Priestley's style.
He didn't think Priestley
brought very much thought
to his scientific foraging.
But Lavoisier was smart enough
to recognize that Priestley
was onto something
and take that piece
of information
and go back to his lab
to figure out exactly what
Priestley had discovered.
Could this be the gas
he was looking for,
the one involved
in rusting and burning?
Lavoisier hurried
to the local apothecary
to buy his own sample
of mercury calx.
Back in England,
Priestley dithered for months
on other projects,
unaware he was in danger
of being scooped.
Finally, it occurred to him:
if this gas he had discovered
supports fire,
might it also support breathing?
Here we have one
of the great discoveries
in the history of chemistry,
and the scene
is kind of amazing.
You've got this man and a mouse.
I put a mouse
into a glass vessel
containing two ounces of the air
from the heated calx of mercury.
If it were common air,
a full-grown mouse
would have survived in it
perhaps a quarter of an hour.
15 minutes pass...
20 minutes pass...
In this air,
my mouse remained
perfectly at ease
for a full half-hour.
That's twice as long
as any mouse has ever survived.
I began to suspect that the air
into which I had put the mouse
was better than common air.
He takes the same mouse,
sticks it back
under the glass,
and sure enough,
the mouse survives
another 30 minutes
in this strange new air.
He realizes that something
fundamentally different
has happened.
This air is some kind
of super air.
I concluded that this air
was between five
and six times better--
that is, more breathable--
than the best common air
I'd ever tested.
He finally has kind of
convinced himself
this air must be safe to breathe
if the mouse is doing so well,
and so he gets up enough courage
to actually try it himself.
It doesn't feel any different
from common air
when I breathe it in.
But I feel peculiarly light
and easy.
In time, this pure air
may be useful as a medicine
or sold to the fashionable
for recreation.
Up to now, only two mice and I
have had the privilege
of breathing it.
As Priestley is conducting
these experiments in England,
across the channel, Lavoisier
is basically going through
the exact same experiments.
Lavoisier, realizing
that this is essentially
the key to the mystery,
gets to work on it.
I found, much to my surprise,
that this air had none of the
properties of "fixed air."
A candle burned in it
with a dazzling splendor,
and charcoal,
instead of just smoldering,
threw sparks
in every direction.
Lavoisier announced his findings
with great fanfare
at the 1775 Easter meeting
of the Academy of Sciences.
All this evidence convinced me
that this air
is more...
more breathable,
more combustible,
and more pure than even
the common air in which we live.
And he gives it
the name "oxygen."
In announcing his findings,
Lavoisier made no mention
of Priestley's revelation
over dinner six months earlier.
Now, Priestley is not
a shrinking violet here.
He hears about this
and he objects.
He should have acknowledged
that my account over dinner led
him to try the experiment.
One should not put one's scythe
into another man's harvest.
I admit I was not the first
to do these experiments.
That claim goes
to Mr. Priestley.
But from the results,
we have drawn diametrically
opposite conclusions.
I may be criticized for having
borrowed from the work
of this celebrated philosopher,
but I trust that the originality
of my conclusions
will not be challenged.
Lavoisier was right.
While it was Priestley
who made the discovery,
it was Lavoisier
who grasped the implications
of this new gas.
Lavoisier was the only one
who understood
what was going on.
Perhaps he didn't understand
perfectly,
but the moment that new element,
which we call oxygen,
was there,
he picks it up
and he runs with it.
Over the next 15 years,
Lavoisier would show that air
is not a simple substance,
as the ancients believed,
but a mixture of two
newly discovered gases.
That water, too,
was a product of two gases.
And that fire
is not an element,
but a process
of combining with oxygen.
Even the solid substances
the ancients had lumped
under the heading "earth"
were now seen in a new way.
Metals like iron
and tin and lead
had been known for centuries.
But in the era of phlogiston,
they were thought to be
compounds
because they had phlogiston
in them.
Lavoisier had turned
this picture upside down.
He showed that by stripping away
the oxygen from the ore,
you got down
to the simpler metal within.
The metal, not the ore,
was the element.
So all four
of the ancient elements--
air, water, earth and fire--
had been abolished, thanks
to the discovery of oxygen.
Once you accept
the existence of oxygen,
the main difficulties of
chemistry appear to evaporate.
Well, if all of chemistry can be
explained without phlogiston,
in all likelihood,
it doesn't exist.
For years, many chemists,
including Joseph Priestley,
refused to abandon
the old theory.
What finally won the day
was the textbook Lavoisier wrote
in 1789
to spread his new
chemical theory.
As it was adopted
around the world,
phlogiston quietly passed
into history.
So the old chemical system
has been essentially destroyed.
Though Lavoisier is often given
most of the credit,
it was really both these men,
working in their very
different ways,
who brought about
this chemical revolution.
They kind of needed each other
in a way.
For science to work, you need
both kinds of scientists, right?
You need the scientists
who are great systematizers,
and then you need the mavericks
and the tinkerers
who are going to open up
new doors for discovery.
One of the doors Priestley
and Lavoisier opened
was a fresh way
to tackle that old question:
what is the world made of?
It was clear now that rocks
of every conceivable variety
might harbor
undiscovered elements
chemically fused with oxygen.
People realized
that if they could release
oxygen from other substances,
what was left behind might be
some of these missing elements
that everybody knew
must be out there.
How many more elements
might you find
by stripping away the oxygen
that liked to bind
to so many things?
Lavoisier's textbook
included the first modern list
of elements:
33 "simple substances."
Some, including light and heat,
were later found
not to be elements.
But it was a start,
and it served as a challenge
to other chemists.
Now that they knew
how to look for them,
chemists began to ask,
"What are the elements?"
The question had never
been asked before
in exactly that way.
And so the discovery of oxygen
really served as a starting gun
for a worldwide race
for new elements.
All over the world,
chemists and amateur collectors
responded to Lavoisier's
challenge,
rapidly identifying
15 new elements.
From Sweden to Mexico,
Connecticut to Siberia,
the discoveries kept coming,
sometimes as many as four
in a single year.
And few things could bring
a chemist more glory
than identifying a new element.
Well, certainly, Lavoisier was
one of the great, great masters
of all time.
In fact...
One of those who would soon
be caught up in the hunt
was a precocious chemist from
the farthest reaches of England.
...pathetic ideas
of phlogiston?
I've just met
a remarkable young man
whose talents
I can only marvel at.
He's not even 21
and has been studying chemistry
for no more than 18 months,
but he's advanced
with such strides
as to overtake everybody.
His name is Davy,
the young chemist.
The young everything.
Humphry Davy was the son
of a simple wood carver
from the remote seaside village
of Penzance,
about a week from London
by stagecoach.
Penzance is right down in the
far southwest corner of England,
and in some sense,
it was the Wild West,
right out beyond the influence
of London and its institutions.
When his father died young,
Humphry left school at 16
and took a job
as an apothecary's apprentice
to support the family.
But he never lost his love
of learning.
He simply resolved
to teach himself.
The same year
that Davy's father dies,
Lavoisier publishes
his Elementary Treatise
on Chemistry.
And young Davy reads this
in the original French.
He starts keeping notebooks
from this very date.
And there's a kind of
intellectual explosion.
Chemistry arose
from the delusions of alchemy,
only to be bound by the chains
of phlogiston.
But through the discoveries of
Black, Priestley and Lavoisier,
it has now been liberated!
Davy started doing experiments
right away.
One of the things he did
was to attack Lavoisier's
theory of heat.
Lavoisier said it was a material
substance called calorique.
And Davy didn't believe this.
Davy thought he could take on
the great man.
He thought heat
was motion of particles.
And he thought
he could prove this
if he could rub two pieces
of ice together--
so no heat would be coming in
from outside--
and the sheer friction
would melt the blocks of ice.
And that's what happened.
To him and his contemporaries,
the experiment
was a convincing one.
Davy's findings, written up
in his first published work,
showed enough promise
to land him a post
closer to Britain's
center of action,
in Bristol,
at the Pneumatic Institution.
So he leaves remote Penzance
to become the assistant
and then the director
of this new institute.
He's only 19, for heaven's sake.
The institution had been founded
in the hope
that some of the gases
discovered by Priestley
and others
would prove useful
in treating diseases.
Davy's job was to make the gases
and then test them.
I took just three breaths
of the gas.
The first produced
a feeling of numbness.
One of the gases he tested
was mostly carbon monoxide,
the poisonous gas now found
in auto exhaust.
He doesn't know exactly
what it is, but he makes it.
And he tests everything
on himself.
It's amazingly reckless,
but it's also very brave.
He acted as if
in sacrificing one life,
he had two or three others
in reserve.
Some days, I half despaired
of seeing him alive
the next morning.
And then he takes his pulse
and he says,
"I do not think I shall die."
And he's ill for 48 hours,
but he survives.
On a number of occasions,
he does nearly kill himself.
When you've got a career to make
and you're coming from a low
point down the social scale
and you've got a long way to go,
why not take a few risks, get
your way up to the top quicker?
The top Davy had in mind was
the very pinnacle of science.
On one page of his Bristol
notebooks, he wrote his own name
next to that of the most famous
British scientist of all time.
Newton and Davy.
So he has this sense
that he and Newton
can go at science together.
It's not arrogance exactly.
It's this tremendous drive,
and he passionately believes
that he will be
a sort of Newton in chemistry.
I don't hesitate at all.
The great master
made a few mistakes.
All his life, that drive
Newton and Davy.
In Bristol, Davy sought out
a group of literary men
whose work would define
the Romantic Age,
including publisher
Joseph Cottle
and poets Robert Southey
and Samuel Taylor Coleridge.
...the assumption that heat
is a simple substance.
Is that what he called caloric?
Precisely.
In looking at that group
in Bristol,
one of the things
I think is wonderful
is there was no gap
between the writers and the
poets and the scientists.
We can discover that the ice
melts by friction alone.
Davy, could not the melting
have been caused
by the temperature
of the room?
That's a very good question,
indeed--
one to which I have
a ready answer.
Every evening,
they're going out,
writing letters to each other,
going on walks together.
And they are young men
with a future.
It's an extraordinary group.
In Davy, these Romantic poets
found a kindred spirit:
a scientist who shared
their sense of wonder at nature
and yearned to reveal
her mysterious ways.
Heat must, in fact,
be the motion of particles.
There's an energy,
an elasticity in his mind
that allows him to seize on
and analyze all subjects.
Living thoughts spring up
like turf under his feet.
Early in his research,
Davy produced a gas
one medical authority had warned
was the cause
of terrible diseases.
He tried it anyway.
This evening,
I breathed nitrous oxide
and experienced a... thrilling
all over me
more pleasurable than anything
I have ever experienced.
The objects around me
became dazzling
and my hearing more acute.
Sometimes I responded
by stamping my feet.
Other times by dancing
around the room
and laughing uncontrollably.
As word of his discovery spread,
many others,
from steam engine pioneer
James Watt
to the king's own doctor,
clamored to try Davy's
"laughing gas."
Coleridge and Southey
both took doses of the gas.
It was very much in keeping
with this Romantic time period.
He's invented
a whole new pleasure.
It makes you laugh and tingle
in every toe and fingertip.
There was a certain amount
of recklessness,
experimenting with drugs.
Why not expand
your consciousness?
It makes you strong and happy!
So gloriously happy!
Excellent airbag.
I'm going for more this evening.
Davy asked each of his subjects
to record their impressions.
The first time I tried
nitrous oxide,
I felt a highly pleasurable
sensation of warmth
over my whole body.
It was like the feeling
I once experienced
entering a warm room
after returning from a walk
in the snow.
I felt no desire to move,
only to laugh at those
who were looking at me.
Davy wrote up their accounts in
his first true scientific book.
But just as he was finishing
the book,
Davy's attention was diverted
by a discovery
that would shake the very
foundations of science.
In 1800, an Italian named
Alessandro Volta
announced that he had created
a new source of electricity.
Up to then, the only sources of
electricity had been lightning,
which was very difficult to tap,
and electrostatic devices like
the ones Priestley had used.
You could get
quite spectacular effects
in the way of flashes and bangs,
but you couldn't get
sustained power.
What Volta did was to establish
that electricity
was something that you could
make a steady supply of:
what we call
an electric current.
Volta's device
was incredibly simple:
a sandwich of alternating
copper and zinc disks,
separated by pieces of cardboard
that had been soaked
in salt water.
But this "voltaic pile,"
the first battery,
electrified the world
of science.
With the battery, you could now
perform a variety of experiments
that had never been possible
before.
And these experiments
were done immediately.
Just weeks after learning
of Volta's discovery,
two British scientists used
a crude battery like this one
to split water
into its two elements:
hydrogen and oxygen.
The electric current was somehow
breaking up the water
into its components.
Even more surprising,
the hydrogen collected at the
negative electrode over here...
And the oxygen collected at the
positive electrode over here.
Why would these two elements
show a preference
for opposite electrical charges?
Intrigued, Davy set aside
his research on gases,
built a voltaic pile
and began doing his own
experiments on electricity.
And it became Davy's
big pursuit in life.
What could this
electric current do?
Volta has given us a key
to some of the most mysterious
recesses of nature.
Till this discovery,
our tools were limited.
Now the possibilities
for chemistry seem boundless.
It's like an undiscovered
country-- a land of promise.
Davy had just begun
to explore that land
when opportunity knocked.
His book on nitrous oxide
had caught the attention
of the founders of the new
Royal Institution in London,
who were looking for a director
for their chemistry laboratory.
And that book had such impact
that it was read in London,
here at the Royal Institution.
It's very, very precise.
It's measured.
It's quantitative science.
And they thought,
"This is the man we must get."
Still only 22, Davy set out
on his next great adventure,
leaving Bristol in 1801
for the city he called
"the great hot-bed
of human power."
When Davy arrived,
his patrons seem to have been
a bit taken aback
to find this still rather raw
country youth.
But his natural eloquence
must have come through
and eventually charmed them.
One of the missions
of the institution
was to offer public lectures
meant to stimulate
an interest in science
among the London elite.
For this purpose,
a theater had been installed
in the institution's building
on Albemarle Street.
Davy started out
as assistant lecturer,
seen here helping his boss
give a dose of laughing gas
to one of the patrons.
But with audiences shrinking
and the institution's
fortunes flagging,
Davy was quickly promoted
to the top job.
Nothing is so fatal to the
progress of the human mind...
Determined to make the most
of this opportunity,
he set out to make each lecture
seem spontaneous.
But to do spontaneous,
what he did was prepare,
prepare.
...as to suppose that there are
no new mysteries left in nature.
He would read through,
in front of his assistants,
drafts of the lecture
to see if it worked.
Who would not
want to learn
the most profound secrets
of nature?
To ascertain her hidden
operations?
The moment Davy
began to lecture,
the audiences packed in.
Science has done much for man,
but it is capable
of doing still more.
He had people absolutely lapping
up what he was pouring out.
There were other chemists
giving public talks elsewhere
in London,
but none held a candle to Davy.
He must have directed his
bright eyes around his audience
so that they felt really
drawn in and mesmerized.
And he would do
dazzling experiments
that he carefully rehearsed with
his assistants the night before,
so they always worked.
And people gasp,
and they cheer and they clap
at the end
of a demonstration.
It's so brilliantly done.
And these lectures became
hugely popular,
and there were the most terrible
traffic jams
outside the Royal Institution.
Albemarle Street became the
first one-way street in London
because there were
so many carriages
bringing people to listen
to his lectures.
He was young,
he was handsome,
he was eloquent.
And there were a number
of young ladies in the audience.
And they're all in the
front rows making notes,
but hanging on Davy's
every word.
Among the lecture notes
in the Royal Institution archive
are these little billets-doux,
little love letters,
often signed with a pseudonym,
and poems to him.
One of his female admirers
invited him to dinner, noting,
"Those eyes are too fine to be
forever gazing over crucibles."
I have audiences
of 400 or 500 people,
many of high rank,
and I suspect that some of them
may become permanently
interested in chemistry.
This science is becoming
the fashion of the day.
Davy's success as a lecturer
and entertainer
brought him wealth, prizes
and acclaim.
But he was growing impatient.
Giving popular lectures
was no way to become
the Newton of chemistry.
By 1806, he had established
enough of a reputation,
and he knew that his work
was supporting
the Royal Institution.
He could say, "Right,
I've been doing your work
"for the last five or six years.
Now I'm going to do
my own work."
An invitation
from an organization
once headed by Newton himself
gave Davy the perfect chance
to show what he could do.
He was asked to lecture
not to the Royal Institution
but to the Royal Society,
the top scientific group
in the world.
He needed to produce some
dramatically original science.
With this goal in mind,
Davy dived into the subject
he'd been itching to return to
ever since Bristol.
Electricity.
Up to now,
we have studied electricity
lightning.
But its slow
and silent operations
on the earth's surface
may prove more important.
From his early experiments,
Davy had learned
that an electric current
could pry apart
the hydrogen and oxygen atoms
that made up water.
You can use a battery
to un-bond things
and find out
what the different elements are.
That gave Davy an idea.
Could he use a bigger battery
to tackle substances
that were harder to break down?
This is something you can do
with this new source
of electricity.
If a small battery
gives you a small effect,
build a larger one
and you get a larger effect.
As the target
for his experiment,
Davy chose caustic potash,
a substance derived from wood
ashes collected in a pot.
Chemists had long suspected
it contained
an undiscovered element,
but no one had been able
to break it down
into simpler stuff.
He believed
that if you could apply
a charge to it in some way,
you would discover something
about its inner nature.
So Davy constructed
a really big battery
because he wanted to see
whether potash could be
decomposed into its elements.
Davy was thus able
to use the resources
of the Royal Institution
to undertake
scientific research,
which had never been
the intention
of the founders of the RI.
But by the time
he began the work,
his Royal Society lecture
was only a month away.
Shall we?
He committed himself
rather recklessly
because he didn't really have
much time.
Would this new battery
be strong enough
to reveal what potash
was made of?
Working at top speed,
he tries various ways
of applying the charge.
Davy first tried
putting a current
through a mixture
of potash and water.
All that did was split the water
into hydrogen and oxygen...
Do you see anything?
No.
...leaving the potash
unaffected.
And then he tried
with dried potash.
And again, nothing happened.
Finally, he moistened
the dry potash just a bit
before applying the electricity.
Dry potash
won't conduct electricity,
but when I added a little water
and applied a strong
electrical current,
I soon observed a vivid action.
There was a violent
effervescence
and small globules.
It sweats forth
these glowing,
shining globules.
They have a metallic luster
very much like mercury,
and some of them exploded
and burnt with a bright flame.
I realized these globules
were the substance
I had been searching for.
And this is a new element,
in fact.
It's potassium, one of the
crucial elements for life.
And he's discovered it.
There's a wonderful description
made by his assistant,
who was actually Edmund Davy,
a young cousin.
He said, "The Professor
became a boy again."
When he saw
those globules of potassium
burst through the crust
of potash and catch fire,
he couldn't contain his joy.
It was some time
before he could compose himself
and continue
with the experiment.
You get the sense
of this huge excitement,
doing things under pressure,
not quite knowing
what will happen,
whether the damn thing
will explode,
and then suddenly,
the unknown reveals itself.
The atoms of potassium
and oxygen,
so firmly glued together,
could be separated
by an electric current
in the same way as those oxygen
and hydrogen atoms in water.
The very next day,
Davy used the same method
to pull apart caustic soda,
or lye,
sodium.
These two new metals
were so soft,
they could be cut with a knife,
and so eager to recombine
with oxygen
that they gave Davy
the perfect demonstration
for his next lecture.
Be ready for anything.
All right.
Davy had turned electricity
into a powerful tool
in the search for new elements.
The year after discovering
potassium and sodium,
he used his battery
to isolate four more elements.
And chemists all over Europe
seized on his technique,
sending the number
of elements even higher.
Sometimes,
the progress of science
is due less
to our intellectual powers
than to the tools
at our disposal.
Nothing promotes the advancement
of knowledge so much
as a new instrument.
Exciting as these
discoveries were,
in time, it would become clear
that Davy's greatest
contribution was his insight
into one of the biggest
questions in chemistry.
Somehow, the particles of matter
have to be glued together
to form molecules.
And it was a complete mystery
as to what this glue might be.
What Davy has had, in effect,
is a big idea.
If electricity
could pry apart the atoms
in water, potash and soda,
might electricity be the force
that stuck those atoms together
in the first place?
Is electricity an essential
property of matter?
Perhaps electricity,
with its plus and minus aspects,
could be this kind of glue.
In every case that we know of,
substances that combine
with each other
have opposite electrical states.
Perhaps this is the reason
they're attracted to each other:
because opposites attract.
It looked as if electricity
might play in chemistry
the sort of role that gravity
played in Newtonian physics.
Remember, he thinks of himself
as on a par in some way
with Newton.
He is going to be the Newton
among chemists.
And in a sense,
he does eventually achieve that.
In the 18th century, electricity
was mostly parlor tricks,
like making somebody's hair
stand on end
and attracting little bits
of paper and so on.
Davy showed that electricity is
a fundamental aspect of matter.
Electricity is what holds us
together.
It is the glue that links
the particles of matter.
And therefore, instead of being
rather a side thing,
electricity is going to be
one of the really central
features of science.
It would take
more than a century
for other scientists to figure
out electricity's role.
But after Davy,
there was no doubt
it would be one of the keys
to solving the mystery
of matter.
Next time on
The Mystery of Matter...
He figures out something
rather extraordinary
about the elements.
The eye is immediately struck
by a pattern:
a regular change
in the horizontal rows
and the vertical columns.
He had discovered an absolutely
fundamental principle of nature.
My mother made her measurements
over again--
ten times, 20 times--
until she was forced
to accept the results.
I proposed a new term to define
this property of matter:
radioactivity.
---
Help everyone explore
new worlds and ideas.
Support your PBS station
One night in 1669, a German
alchemist named Hennig Brandt
was searching, as he did every
night, for a way to make gold.
For some time, Brandt had
focused his research on urine.
He was certain the "golden
stream" held the key.
Tonight, his patience
would at last be rewarded.
He had boiled the urine down
to a concentrated paste.
Now he subjected it
to intense heat.
Was this the legendary elixir
that would turn lead into gold?
Alas, it was not.
Brandt had stumbled
on the element phosphorus.
This is how the discovery
of elements began:
with people trying to turn
the substances of nature
into something useful
or valuable.
But people
are naturally curious,
so as they worked
with these materials,
they began to wonder,
"What is this stuff?
What is the world made of?"
Thousands of years ago, the
Greeks proposed that the world
is actually made of just
four elements in combination:
air, water, earth and fire.
Today, we know that matter
actually comes in more than
a hundred distinct varieties,
neatly arranged in the periodic
table of the elements.
But for most of history,
matter was a profound mystery,
a 2,000-year detective story
in which people across the world
were trying to identify
the elements
and figure out how to use them.
It's an amazing story, filled
with unforgettable characters.
In this series, you'll meet
seven extraordinary scientists
whose findings drove the search
for the elements.
So join me
as we retrace the steps
of these chemical detectives
as they struggle to solve
the mystery of matter.
*
One of the first big clues
in solving the mystery of matter
came from the discovery
of the most immaterial stuff
you can imagine: air.
Of course, people have always
known about air.
They could feel the wind
on their faces
and see its powerful effects
in storms.
What they didn't know
was that there's more
than one kind of air.
That changed in 1754,
when a young Scottish medical
student named Joseph Black
set out to find a cure
for kidney stones.
He poured acid
on this chalky substance...
...and trapped the air
that came out.
To his surprise, this "air"
didn't behave like air at all.
It was heavier than ordinary air
and promptly put out a flame.
Black's discovery of fixed air--
what we now call
carbon dioxide--
was a turning point
in the history of science.
People had long known
about liquids and solids.
Now suddenly, they realized
there was a third state
of matter-- gases--
of which air
is just one example.
Over the next 20 years,
the exploration
of this new dimension
would transform
our understanding of matter.
After Black's discovery,
British scientists quickly
identified two more new gases:
hydrogen and nitrogen.
And then in the early 1770s,
that astonishing investigator
Joseph Priestley
discovers all sorts of new airs.
Priestley was a minister
by trade,
but also an amateur scientist--
what was then called
a natural philosopher.
He was a great dabbler in things
and was constantly getting
obsessed with new fields.
Fields like the new science
of gases.
Priestley's style of science
is very interesting.
He's a kind of inspired forager.
He's basically messing around
with different things
to see what will happen.
One of the things Priestley did
was to pour acid on everything.
He collected those bubbles,
tested them thoroughly
and discovered all sorts
of amazing properties.
By "messing around" in this way,
Priestley discovered
nine new gases--
more than anyone else
in the world.
He was very much open
to chance discoveries.
He would stumble across things
and he would follow
his instincts.
And he was always looking
for these kind of fortuitous
accidents.
One such accident happened
in 1767,
when Priestley was assigned
a new congregation.
They put him in a house
that happens to be right next
to a brewery.
And this turns out to be an
incredible stroke of good luck.
Priestley, being the constant
investigator that he was,
would kind of pop over
and see what was going on
at this brewery.
Just above the vats of beer,
he discovered a haze
of carbon dioxide
bubbling up
from the fermenting brew.
And he decided he wanted to do
some experiments
with their beer.
Well, fortunately,
they said yes.
Priestley found that
if he simply poured water
from one glass to another
over the surface,
the water would absorb the gas
rising from the beer.
The result was
refreshingly bubbly.
By 1772, he had invented
a better method:
generating carbon dioxide
and injecting it directly
into water.
In the space of two
or three minutes,
I can make a glass
of exceedingly pleasant
sparkling water.
You can't tell the difference
between this
and natural mineral water.
Priestley had invented
carbonation.
Remember that the next time
you enjoy a soft drink.
But with this act,
he also set in motion
a series of improbable events
that would soon overturn
our understanding of matter.
It began when a British doctor
suggested Priestley's
"windy water"
might be effective
as a treatment for scurvy,
a disease that plagued sailors
on long sea voyages.
Scurvy was a huge problem for
the military during that period,
and so the idea that there was
this potential solution
that also happened to be
a tasty beverage was appealing.
In 1772, Priestley addressed
Britain's leading scientific
organization, the Royal Society,
and published a pamphlet
describing his method
for making soda water.
He urged the British navy
to test the potential cure.
Quick to pick up
on this development
was a defrocked Portuguese monk
named João Jacinto de Magellan.
A distant relative of the great
Portuguese navigator,
he was now serving
as a French industrial spy.
Magellan is in the employ
of the French government
and is there basically
scouting out the Royal Society
for interesting items
that he might be able
to bring back to his bosses.
Sensing a potential
military secret,
Magellan alerted his handler
back in France:
Commerce Minister Jean Charles
Trudaine de Montigny.
Trudaine was interested
in science,
was a member of the French
Royal Academy of Sciences,
and immediately saw
the possible value of this.
Trudaine, in turn,
called on one of France's
brightest young chemists,
Antoine Laurent Lavoisier.
"I know your precision when it
comes to physics and chemistry,
"and I'm giving you a chance to
be of service to your country.
"Please repeat these experiments
and add your own observations.
The value of these discoveries
depends on our moving quickly."
I hope you will not be long in
getting this little work done.
Trudaine probably intended
this politely phrased letter
as an order
rather than a request.
Lavoisier really couldn't
ignore it.
Though soda water would turn out
to be useless against scurvy,
this pointed suggestion
by a government official,
acting on a tip
from a Portuguese spy,
would set Lavoisier on the path
toward his greatest discoveries.
Born into a well-to-do
Parisian family,
Lavoisier had received
a fine education
and taken a degree in law.
Now 28, he had joined
a consortium
that collected taxes
for King Louis XV.
As a result, Lavoisier became
a very wealthy man.
But his true passion
was chemistry.
Lavoisier spent three hours
in his private laboratory
before work every day
and returned there after dinner,
often accompanied
by his young wife.
Marie-Anne Paulze
was the daughter
of one of Lavoisier's
business partners.
She was just 13
when they were married,
but bright, outgoing and mature
beyond her years.
Marie-Anne was virtually
his collaborator.
She knew English,
learned chemistry,
assisted Lavoisier
in the laboratory.
She was an extraordinary person.
Had she lived in our own time,
she probably would have become
an outstanding scientist
in her own right.
One of Marie-Anne's
most important roles
was to create the diagrams
and illustrations
that accompanied her husband's
published work.
Marie Lavoisier's drawings
give us the eyes
to look directly
into Lavoisier's laboratory.
We can see the people.
We can see the devices.
We can see the arrangement
of those devices.
We can understand
what Lavoisier did
so much better
because of what Marie drew.
Spurred on by Trudaine,
Lavoisier eagerly studied
fresh translations
of Black, Priestley
and the other British chemists
who had pioneered
the study of "airs."
The work of these previous
experimenters
merely hints at what's happening
when air is taken up or released
by different substances.
I shall review all their work,
repeat all their experiments,
taking new precautions,
in order to develop
a coherent theory.
This subject, I believe,
is destined to bring about
a revolution in physics
and chemistry.
What made this new science
of air so revolutionary
was that it threatened to topple
the reigning theory
of chemistry,
a theory inspired
by the mystery of fire.
Most chemists believed fire
was due to some fiery principle
that was given up
during combustion.
And all our senses
seem to confirm this idea.
Heat, light, smoke-- all are
released as the fire burns.
By the mid-1700s,
this essence of fire had been
given a name: phlogiston.
Phlogiston was the foundation
of chemistry's leading theory
for nearly a century,
because it seemed to explain
things like metals and rust.
When iron ore was heated
in the presence of charcoal,
phlogiston from the charcoal
fused with the ore
to form metallic iron.
When the iron was exposed
to air or water,
the metal released
its phlogiston as it rusted.
Other metals went
through the same process,
forming the green verdigris
of copper, for example.
Ore plus phlogiston
equals metal.
Metal minus phlogiston
equals rust,
or what was then called
a "calx."
Only there was a problem:
the calx was heavier
than the metal,
even though phlogiston
had left the metal.
It's lost something,
and yet it was heavier.
The calx should weigh less
than the original metal,
but it doesn't.
The calx is heavier
than the metal.
Though many chemists were aware
of this contradiction,
they let it pass
because phlogiston otherwise
worked so well.
But Lavoisier
was really troubled by this
because he was obsessed
with the weights
of his experimental ingredients.
Lavoisier was very careful
to get very good instruments.
He probably at one point
had the largest
and most complete
private laboratory on earth.
With my precision scales,
imported from England
at great expense,
I measure the weight
of each substance
at the beginning and end
of every chemical reaction.
Lavoisier was a master of this
balance sheet kind of chemistry.
Remember, he was
a tax administrator by day.
He knew a lot about accounting.
And so this kind
of ledger-keeping
was natural to him.
It is a fundamental truth
of chemistry
that the same amount
of matter exists
before and after
each experiment.
Nothing new is created,
nothing lost.
The whole art of performing
chemical experiments
rests on this principle.
Today, we call this idea
the conservation of matter.
When you carry out
a chemical reaction,
what comes out has to be
exactly equal to what goes in.
The total weight must remain
precisely the same.
If not,
there's an error somewhere.
He wasn't the first to assume
conservation of matter,
but Lavoisier applied this idea
more rigorously
than anyone had before.
And it worked very effectively
as a tool: a tool of discovery.
The power of Lavoisier's method
would become clear
in October 1772, when he set out
to solve the riddle
of why metals gain weight
when they form calxes.
Common sense suggested
that when things rust,
they must lose weight.
They fall apart.
They become brittle and weak.
Lavoisier was interested
in actually measuring
what happened.
He conducted his experiments
in public,
relying on a huge burning lens
that focused the sun's rays
to produce intense heat,
while elegantly dressed
bystanders watched in amazement.
Lavoisier placed a calx of lead,
mixed with charcoal,
inside a glass vessel
partially filled with water,
then subjected it to the intense
heat of the burning lens.
The result was extraordinary.
As the calx changes
back into the metal,
it releases a large quantity
of air.
This air forms a volume
1,000 times greater
than the calx it came from.
This startling finding suggested
a radical idea.
If air came out as the calx
changed back into a metal,
could it have gone in
when the calx was formed?
Could air be the reason calxes
were heavier than expected?
Lavoisier also found that when
he burned elements like sulfur,
they, too, gained weight.
There was then no doubt.
I realized that the increase
in weight occurs
because a portion of the air
is absorbed
into the solid material.
He knew he was onto something
very important.
He knew that the element
did not lose mass;
it gained mass.
It took up some part of the air.
I felt I must secure my right
to this important discovery.
So I deposited a note
with le Secretaire de l'Academy
to remain sealed
until I was ready
to make my experiments public.
He's discovered
what seems to be evidence
by weighing things
that seem to flatly contradict
what the phlogiston theory
is predicting.
Despite what our senses tell us,
both rusting and burning
involve absorbing something
from the air--
just the opposite
of what chemistry's
reigning theory held.
It had been known for 100 years
that metals gain weight
when they become calxes,
but no one had bothered to
really investigate this anomaly.
By focusing so intently
on weight,
Lavoisier had challenged the
very foundation of chemistry.
And he'd identified the source
of that weight gain.
Air was somehow involved.
But was it air itself,
or some part of the air?
And if so, what part?
The identity of the mystery gas
eluded him for two years.
He was still stumped
in late 1774.
But the answer
would soon be delivered
by Joseph Priestley.
By this time, Priestley had
begun to study something
called the red calx of mercury.
Mercury is a strange metal,
one of just two elements that is
liquid at room temperature.
But like other metals,
it forms a calx,
a red solid that pharmacists
of the 1700s used
to treat venereal disease.
Chemists had noticed something
unusual about this calx.
They could convert it
back into metallic mercury
simply by heating it.
No charcoal--
no source of phlogiston--
was needed.
This was theoretically
impossible.
How could it be?
The ever-curious Priestley
wanted to know,
so in August 1774, he obtained
a sample of mercury calx
and used his own burning lens
to heat it with sunlight.
That reddish substance
in turn decomposes,
giving back mercury,
but also a gas.
Priestley collects this air
because he likes
to test these gases
to see what properties
they have.
If it were his old friend
"fixed air,"
the candle would go out.
But what he found
about this air
was that it had quite
extraordinary properties.
What astounded me was that
the candle burned in this air
with remarkable vigor.
The flame was bigger and
brighter than in ordinary air.
Something in this air seems
almost better than normal air,
which is very puzzling.
I was utterly at a loss.
How could I explain this?
Dr. Priestley, have you been
to the Continent before?
No, this is my first time.
Two months later,
on a visit to Paris,
Priestley was invited to dine
with members
of the Royal Academy
of Sciences,
including Antoine Lavoisier.
J'ai récemment réalisé...
Priestley tells Lavoisier
in his very broken French
about his new discovery.
...avec les résultats
tres intéressants.
I described this experiment
at the table
of Monsieur Lavoisier.
I never make the least secret
of anything I do.
...la meme aire
de plombe rouge.
Everything that he came up with,
every new experiment
that he did,
even when he wasn't sure
what the results meant...
Qu'est-ce que c'est
ce plombe rouge?
...he was constantly
sharing that information
with as many people as possible.
Mais à ma grande surprise...
I also told them that
it produced a kind of air
in which a candle burned much
better than in common air.
...mieux que dans l'air commun.
At this, the entire company,
including Monsieur
and Madame Lavoisier,
expressed great surprise.
I'm sure they cannot have
forgotten these events.
Monsieur Priestley,
etes-vous bien sûr que
ce n'était pas l'air fixe?
If you want,
I can translate for you.
Merci.
Are you sure that what you found
was not fixed air?
Absolutely.
But I'm not yet sure
of what it was.
Lavoisier did not appreciate
Priestley's style.
He didn't think Priestley
brought very much thought
to his scientific foraging.
But Lavoisier was smart enough
to recognize that Priestley
was onto something
and take that piece
of information
and go back to his lab
to figure out exactly what
Priestley had discovered.
Could this be the gas
he was looking for,
the one involved
in rusting and burning?
Lavoisier hurried
to the local apothecary
to buy his own sample
of mercury calx.
Back in England,
Priestley dithered for months
on other projects,
unaware he was in danger
of being scooped.
Finally, it occurred to him:
if this gas he had discovered
supports fire,
might it also support breathing?
Here we have one
of the great discoveries
in the history of chemistry,
and the scene
is kind of amazing.
You've got this man and a mouse.
I put a mouse
into a glass vessel
containing two ounces of the air
from the heated calx of mercury.
If it were common air,
a full-grown mouse
would have survived in it
perhaps a quarter of an hour.
15 minutes pass...
20 minutes pass...
In this air,
my mouse remained
perfectly at ease
for a full half-hour.
That's twice as long
as any mouse has ever survived.
I began to suspect that the air
into which I had put the mouse
was better than common air.
He takes the same mouse,
sticks it back
under the glass,
and sure enough,
the mouse survives
another 30 minutes
in this strange new air.
He realizes that something
fundamentally different
has happened.
This air is some kind
of super air.
I concluded that this air
was between five
and six times better--
that is, more breathable--
than the best common air
I'd ever tested.
He finally has kind of
convinced himself
this air must be safe to breathe
if the mouse is doing so well,
and so he gets up enough courage
to actually try it himself.
It doesn't feel any different
from common air
when I breathe it in.
But I feel peculiarly light
and easy.
In time, this pure air
may be useful as a medicine
or sold to the fashionable
for recreation.
Up to now, only two mice and I
have had the privilege
of breathing it.
As Priestley is conducting
these experiments in England,
across the channel, Lavoisier
is basically going through
the exact same experiments.
Lavoisier, realizing
that this is essentially
the key to the mystery,
gets to work on it.
I found, much to my surprise,
that this air had none of the
properties of "fixed air."
A candle burned in it
with a dazzling splendor,
and charcoal,
instead of just smoldering,
threw sparks
in every direction.
Lavoisier announced his findings
with great fanfare
at the 1775 Easter meeting
of the Academy of Sciences.
All this evidence convinced me
that this air
is more...
more breathable,
more combustible,
and more pure than even
the common air in which we live.
And he gives it
the name "oxygen."
In announcing his findings,
Lavoisier made no mention
of Priestley's revelation
over dinner six months earlier.
Now, Priestley is not
a shrinking violet here.
He hears about this
and he objects.
He should have acknowledged
that my account over dinner led
him to try the experiment.
One should not put one's scythe
into another man's harvest.
I admit I was not the first
to do these experiments.
That claim goes
to Mr. Priestley.
But from the results,
we have drawn diametrically
opposite conclusions.
I may be criticized for having
borrowed from the work
of this celebrated philosopher,
but I trust that the originality
of my conclusions
will not be challenged.
Lavoisier was right.
While it was Priestley
who made the discovery,
it was Lavoisier
who grasped the implications
of this new gas.
Lavoisier was the only one
who understood
what was going on.
Perhaps he didn't understand
perfectly,
but the moment that new element,
which we call oxygen,
was there,
he picks it up
and he runs with it.
Over the next 15 years,
Lavoisier would show that air
is not a simple substance,
as the ancients believed,
but a mixture of two
newly discovered gases.
That water, too,
was a product of two gases.
And that fire
is not an element,
but a process
of combining with oxygen.
Even the solid substances
the ancients had lumped
under the heading "earth"
were now seen in a new way.
Metals like iron
and tin and lead
had been known for centuries.
But in the era of phlogiston,
they were thought to be
compounds
because they had phlogiston
in them.
Lavoisier had turned
this picture upside down.
He showed that by stripping away
the oxygen from the ore,
you got down
to the simpler metal within.
The metal, not the ore,
was the element.
So all four
of the ancient elements--
air, water, earth and fire--
had been abolished, thanks
to the discovery of oxygen.
Once you accept
the existence of oxygen,
the main difficulties of
chemistry appear to evaporate.
Well, if all of chemistry can be
explained without phlogiston,
in all likelihood,
it doesn't exist.
For years, many chemists,
including Joseph Priestley,
refused to abandon
the old theory.
What finally won the day
was the textbook Lavoisier wrote
in 1789
to spread his new
chemical theory.
As it was adopted
around the world,
phlogiston quietly passed
into history.
So the old chemical system
has been essentially destroyed.
Though Lavoisier is often given
most of the credit,
it was really both these men,
working in their very
different ways,
who brought about
this chemical revolution.
They kind of needed each other
in a way.
For science to work, you need
both kinds of scientists, right?
You need the scientists
who are great systematizers,
and then you need the mavericks
and the tinkerers
who are going to open up
new doors for discovery.
One of the doors Priestley
and Lavoisier opened
was a fresh way
to tackle that old question:
what is the world made of?
It was clear now that rocks
of every conceivable variety
might harbor
undiscovered elements
chemically fused with oxygen.
People realized
that if they could release
oxygen from other substances,
what was left behind might be
some of these missing elements
that everybody knew
must be out there.
How many more elements
might you find
by stripping away the oxygen
that liked to bind
to so many things?
Lavoisier's textbook
included the first modern list
of elements:
33 "simple substances."
Some, including light and heat,
were later found
not to be elements.
But it was a start,
and it served as a challenge
to other chemists.
Now that they knew
how to look for them,
chemists began to ask,
"What are the elements?"
The question had never
been asked before
in exactly that way.
And so the discovery of oxygen
really served as a starting gun
for a worldwide race
for new elements.
All over the world,
chemists and amateur collectors
responded to Lavoisier's
challenge,
rapidly identifying
15 new elements.
From Sweden to Mexico,
Connecticut to Siberia,
the discoveries kept coming,
sometimes as many as four
in a single year.
And few things could bring
a chemist more glory
than identifying a new element.
Well, certainly, Lavoisier was
one of the great, great masters
of all time.
In fact...
One of those who would soon
be caught up in the hunt
was a precocious chemist from
the farthest reaches of England.
...pathetic ideas
of phlogiston?
I've just met
a remarkable young man
whose talents
I can only marvel at.
He's not even 21
and has been studying chemistry
for no more than 18 months,
but he's advanced
with such strides
as to overtake everybody.
His name is Davy,
the young chemist.
The young everything.
Humphry Davy was the son
of a simple wood carver
from the remote seaside village
of Penzance,
about a week from London
by stagecoach.
Penzance is right down in the
far southwest corner of England,
and in some sense,
it was the Wild West,
right out beyond the influence
of London and its institutions.
When his father died young,
Humphry left school at 16
and took a job
as an apothecary's apprentice
to support the family.
But he never lost his love
of learning.
He simply resolved
to teach himself.
The same year
that Davy's father dies,
Lavoisier publishes
his Elementary Treatise
on Chemistry.
And young Davy reads this
in the original French.
He starts keeping notebooks
from this very date.
And there's a kind of
intellectual explosion.
Chemistry arose
from the delusions of alchemy,
only to be bound by the chains
of phlogiston.
But through the discoveries of
Black, Priestley and Lavoisier,
it has now been liberated!
Davy started doing experiments
right away.
One of the things he did
was to attack Lavoisier's
theory of heat.
Lavoisier said it was a material
substance called calorique.
And Davy didn't believe this.
Davy thought he could take on
the great man.
He thought heat
was motion of particles.
And he thought
he could prove this
if he could rub two pieces
of ice together--
so no heat would be coming in
from outside--
and the sheer friction
would melt the blocks of ice.
And that's what happened.
To him and his contemporaries,
the experiment
was a convincing one.
Davy's findings, written up
in his first published work,
showed enough promise
to land him a post
closer to Britain's
center of action,
in Bristol,
at the Pneumatic Institution.
So he leaves remote Penzance
to become the assistant
and then the director
of this new institute.
He's only 19, for heaven's sake.
The institution had been founded
in the hope
that some of the gases
discovered by Priestley
and others
would prove useful
in treating diseases.
Davy's job was to make the gases
and then test them.
I took just three breaths
of the gas.
The first produced
a feeling of numbness.
One of the gases he tested
was mostly carbon monoxide,
the poisonous gas now found
in auto exhaust.
He doesn't know exactly
what it is, but he makes it.
And he tests everything
on himself.
It's amazingly reckless,
but it's also very brave.
He acted as if
in sacrificing one life,
he had two or three others
in reserve.
Some days, I half despaired
of seeing him alive
the next morning.
And then he takes his pulse
and he says,
"I do not think I shall die."
And he's ill for 48 hours,
but he survives.
On a number of occasions,
he does nearly kill himself.
When you've got a career to make
and you're coming from a low
point down the social scale
and you've got a long way to go,
why not take a few risks, get
your way up to the top quicker?
The top Davy had in mind was
the very pinnacle of science.
On one page of his Bristol
notebooks, he wrote his own name
next to that of the most famous
British scientist of all time.
Newton and Davy.
So he has this sense
that he and Newton
can go at science together.
It's not arrogance exactly.
It's this tremendous drive,
and he passionately believes
that he will be
a sort of Newton in chemistry.
I don't hesitate at all.
The great master
made a few mistakes.
All his life, that drive
Newton and Davy.
In Bristol, Davy sought out
a group of literary men
whose work would define
the Romantic Age,
including publisher
Joseph Cottle
and poets Robert Southey
and Samuel Taylor Coleridge.
...the assumption that heat
is a simple substance.
Is that what he called caloric?
Precisely.
In looking at that group
in Bristol,
one of the things
I think is wonderful
is there was no gap
between the writers and the
poets and the scientists.
We can discover that the ice
melts by friction alone.
Davy, could not the melting
have been caused
by the temperature
of the room?
That's a very good question,
indeed--
one to which I have
a ready answer.
Every evening,
they're going out,
writing letters to each other,
going on walks together.
And they are young men
with a future.
It's an extraordinary group.
In Davy, these Romantic poets
found a kindred spirit:
a scientist who shared
their sense of wonder at nature
and yearned to reveal
her mysterious ways.
Heat must, in fact,
be the motion of particles.
There's an energy,
an elasticity in his mind
that allows him to seize on
and analyze all subjects.
Living thoughts spring up
like turf under his feet.
Early in his research,
Davy produced a gas
one medical authority had warned
was the cause
of terrible diseases.
He tried it anyway.
This evening,
I breathed nitrous oxide
and experienced a... thrilling
all over me
more pleasurable than anything
I have ever experienced.
The objects around me
became dazzling
and my hearing more acute.
Sometimes I responded
by stamping my feet.
Other times by dancing
around the room
and laughing uncontrollably.
As word of his discovery spread,
many others,
from steam engine pioneer
James Watt
to the king's own doctor,
clamored to try Davy's
"laughing gas."
Coleridge and Southey
both took doses of the gas.
It was very much in keeping
with this Romantic time period.
He's invented
a whole new pleasure.
It makes you laugh and tingle
in every toe and fingertip.
There was a certain amount
of recklessness,
experimenting with drugs.
Why not expand
your consciousness?
It makes you strong and happy!
So gloriously happy!
Excellent airbag.
I'm going for more this evening.
Davy asked each of his subjects
to record their impressions.
The first time I tried
nitrous oxide,
I felt a highly pleasurable
sensation of warmth
over my whole body.
It was like the feeling
I once experienced
entering a warm room
after returning from a walk
in the snow.
I felt no desire to move,
only to laugh at those
who were looking at me.
Davy wrote up their accounts in
his first true scientific book.
But just as he was finishing
the book,
Davy's attention was diverted
by a discovery
that would shake the very
foundations of science.
In 1800, an Italian named
Alessandro Volta
announced that he had created
a new source of electricity.
Up to then, the only sources of
electricity had been lightning,
which was very difficult to tap,
and electrostatic devices like
the ones Priestley had used.
You could get
quite spectacular effects
in the way of flashes and bangs,
but you couldn't get
sustained power.
What Volta did was to establish
that electricity
was something that you could
make a steady supply of:
what we call
an electric current.
Volta's device
was incredibly simple:
a sandwich of alternating
copper and zinc disks,
separated by pieces of cardboard
that had been soaked
in salt water.
But this "voltaic pile,"
the first battery,
electrified the world
of science.
With the battery, you could now
perform a variety of experiments
that had never been possible
before.
And these experiments
were done immediately.
Just weeks after learning
of Volta's discovery,
two British scientists used
a crude battery like this one
to split water
into its two elements:
hydrogen and oxygen.
The electric current was somehow
breaking up the water
into its components.
Even more surprising,
the hydrogen collected at the
negative electrode over here...
And the oxygen collected at the
positive electrode over here.
Why would these two elements
show a preference
for opposite electrical charges?
Intrigued, Davy set aside
his research on gases,
built a voltaic pile
and began doing his own
experiments on electricity.
And it became Davy's
big pursuit in life.
What could this
electric current do?
Volta has given us a key
to some of the most mysterious
recesses of nature.
Till this discovery,
our tools were limited.
Now the possibilities
for chemistry seem boundless.
It's like an undiscovered
country-- a land of promise.
Davy had just begun
to explore that land
when opportunity knocked.
His book on nitrous oxide
had caught the attention
of the founders of the new
Royal Institution in London,
who were looking for a director
for their chemistry laboratory.
And that book had such impact
that it was read in London,
here at the Royal Institution.
It's very, very precise.
It's measured.
It's quantitative science.
And they thought,
"This is the man we must get."
Still only 22, Davy set out
on his next great adventure,
leaving Bristol in 1801
for the city he called
"the great hot-bed
of human power."
When Davy arrived,
his patrons seem to have been
a bit taken aback
to find this still rather raw
country youth.
But his natural eloquence
must have come through
and eventually charmed them.
One of the missions
of the institution
was to offer public lectures
meant to stimulate
an interest in science
among the London elite.
For this purpose,
a theater had been installed
in the institution's building
on Albemarle Street.
Davy started out
as assistant lecturer,
seen here helping his boss
give a dose of laughing gas
to one of the patrons.
But with audiences shrinking
and the institution's
fortunes flagging,
Davy was quickly promoted
to the top job.
Nothing is so fatal to the
progress of the human mind...
Determined to make the most
of this opportunity,
he set out to make each lecture
seem spontaneous.
But to do spontaneous,
what he did was prepare,
prepare.
...as to suppose that there are
no new mysteries left in nature.
He would read through,
in front of his assistants,
drafts of the lecture
to see if it worked.
Who would not
want to learn
the most profound secrets
of nature?
To ascertain her hidden
operations?
The moment Davy
began to lecture,
the audiences packed in.
Science has done much for man,
but it is capable
of doing still more.
He had people absolutely lapping
up what he was pouring out.
There were other chemists
giving public talks elsewhere
in London,
but none held a candle to Davy.
He must have directed his
bright eyes around his audience
so that they felt really
drawn in and mesmerized.
And he would do
dazzling experiments
that he carefully rehearsed with
his assistants the night before,
so they always worked.
And people gasp,
and they cheer and they clap
at the end
of a demonstration.
It's so brilliantly done.
And these lectures became
hugely popular,
and there were the most terrible
traffic jams
outside the Royal Institution.
Albemarle Street became the
first one-way street in London
because there were
so many carriages
bringing people to listen
to his lectures.
He was young,
he was handsome,
he was eloquent.
And there were a number
of young ladies in the audience.
And they're all in the
front rows making notes,
but hanging on Davy's
every word.
Among the lecture notes
in the Royal Institution archive
are these little billets-doux,
little love letters,
often signed with a pseudonym,
and poems to him.
One of his female admirers
invited him to dinner, noting,
"Those eyes are too fine to be
forever gazing over crucibles."
I have audiences
of 400 or 500 people,
many of high rank,
and I suspect that some of them
may become permanently
interested in chemistry.
This science is becoming
the fashion of the day.
Davy's success as a lecturer
and entertainer
brought him wealth, prizes
and acclaim.
But he was growing impatient.
Giving popular lectures
was no way to become
the Newton of chemistry.
By 1806, he had established
enough of a reputation,
and he knew that his work
was supporting
the Royal Institution.
He could say, "Right,
I've been doing your work
"for the last five or six years.
Now I'm going to do
my own work."
An invitation
from an organization
once headed by Newton himself
gave Davy the perfect chance
to show what he could do.
He was asked to lecture
not to the Royal Institution
but to the Royal Society,
the top scientific group
in the world.
He needed to produce some
dramatically original science.
With this goal in mind,
Davy dived into the subject
he'd been itching to return to
ever since Bristol.
Electricity.
Up to now,
we have studied electricity
lightning.
But its slow
and silent operations
on the earth's surface
may prove more important.
From his early experiments,
Davy had learned
that an electric current
could pry apart
the hydrogen and oxygen atoms
that made up water.
You can use a battery
to un-bond things
and find out
what the different elements are.
That gave Davy an idea.
Could he use a bigger battery
to tackle substances
that were harder to break down?
This is something you can do
with this new source
of electricity.
If a small battery
gives you a small effect,
build a larger one
and you get a larger effect.
As the target
for his experiment,
Davy chose caustic potash,
a substance derived from wood
ashes collected in a pot.
Chemists had long suspected
it contained
an undiscovered element,
but no one had been able
to break it down
into simpler stuff.
He believed
that if you could apply
a charge to it in some way,
you would discover something
about its inner nature.
So Davy constructed
a really big battery
because he wanted to see
whether potash could be
decomposed into its elements.
Davy was thus able
to use the resources
of the Royal Institution
to undertake
scientific research,
which had never been
the intention
of the founders of the RI.
But by the time
he began the work,
his Royal Society lecture
was only a month away.
Shall we?
He committed himself
rather recklessly
because he didn't really have
much time.
Would this new battery
be strong enough
to reveal what potash
was made of?
Working at top speed,
he tries various ways
of applying the charge.
Davy first tried
putting a current
through a mixture
of potash and water.
All that did was split the water
into hydrogen and oxygen...
Do you see anything?
No.
...leaving the potash
unaffected.
And then he tried
with dried potash.
And again, nothing happened.
Finally, he moistened
the dry potash just a bit
before applying the electricity.
Dry potash
won't conduct electricity,
but when I added a little water
and applied a strong
electrical current,
I soon observed a vivid action.
There was a violent
effervescence
and small globules.
It sweats forth
these glowing,
shining globules.
They have a metallic luster
very much like mercury,
and some of them exploded
and burnt with a bright flame.
I realized these globules
were the substance
I had been searching for.
And this is a new element,
in fact.
It's potassium, one of the
crucial elements for life.
And he's discovered it.
There's a wonderful description
made by his assistant,
who was actually Edmund Davy,
a young cousin.
He said, "The Professor
became a boy again."
When he saw
those globules of potassium
burst through the crust
of potash and catch fire,
he couldn't contain his joy.
It was some time
before he could compose himself
and continue
with the experiment.
You get the sense
of this huge excitement,
doing things under pressure,
not quite knowing
what will happen,
whether the damn thing
will explode,
and then suddenly,
the unknown reveals itself.
The atoms of potassium
and oxygen,
so firmly glued together,
could be separated
by an electric current
in the same way as those oxygen
and hydrogen atoms in water.
The very next day,
Davy used the same method
to pull apart caustic soda,
or lye,
sodium.
These two new metals
were so soft,
they could be cut with a knife,
and so eager to recombine
with oxygen
that they gave Davy
the perfect demonstration
for his next lecture.
Be ready for anything.
All right.
Davy had turned electricity
into a powerful tool
in the search for new elements.
The year after discovering
potassium and sodium,
he used his battery
to isolate four more elements.
And chemists all over Europe
seized on his technique,
sending the number
of elements even higher.
Sometimes,
the progress of science
is due less
to our intellectual powers
than to the tools
at our disposal.
Nothing promotes the advancement
of knowledge so much
as a new instrument.
Exciting as these
discoveries were,
in time, it would become clear
that Davy's greatest
contribution was his insight
into one of the biggest
questions in chemistry.
Somehow, the particles of matter
have to be glued together
to form molecules.
And it was a complete mystery
as to what this glue might be.
What Davy has had, in effect,
is a big idea.
If electricity
could pry apart the atoms
in water, potash and soda,
might electricity be the force
that stuck those atoms together
in the first place?
Is electricity an essential
property of matter?
Perhaps electricity,
with its plus and minus aspects,
could be this kind of glue.
In every case that we know of,
substances that combine
with each other
have opposite electrical states.
Perhaps this is the reason
they're attracted to each other:
because opposites attract.
It looked as if electricity
might play in chemistry
the sort of role that gravity
played in Newtonian physics.
Remember, he thinks of himself
as on a par in some way
with Newton.
He is going to be the Newton
among chemists.
And in a sense,
he does eventually achieve that.
In the 18th century, electricity
was mostly parlor tricks,
like making somebody's hair
stand on end
and attracting little bits
of paper and so on.
Davy showed that electricity is
a fundamental aspect of matter.
Electricity is what holds us
together.
It is the glue that links
the particles of matter.
And therefore, instead of being
rather a side thing,
electricity is going to be
one of the really central
features of science.
It would take
more than a century
for other scientists to figure
out electricity's role.
But after Davy,
there was no doubt
it would be one of the keys
to solving the mystery
of matter.
Next time on
The Mystery of Matter...
He figures out something
rather extraordinary
about the elements.
The eye is immediately struck
by a pattern:
a regular change
in the horizontal rows
and the vertical columns.
He had discovered an absolutely
fundamental principle of nature.
My mother made her measurements
over again--
ten times, 20 times--
until she was forced
to accept the results.
I proposed a new term to define
this property of matter:
radioactivity.