Narrator: Paper umbrellas
originated in china
and eventually spread
throughout asia.
Initially, their purpose
was solely practical --
to protect against rain
and to provide shade
from the scorching sun.
But before long, they took on
symbolic significance
and were incorporated into
many ceremonies and rituals.
They're called
oil paper umbrellas
because the paper
is coated with oil
or, like these, with oil paint,
making the umbrella waterproof.
At this workshop
in northern thailand,
they cut a bamboo log
to the length
of the umbrella's radius,
then shave off the bark.
They split the log into strips
of equal thickness,
then group these ribs,
as they're called,
into bundles of 28.
Each bundle will become
the frame of one umbrella.
Next, they thin out
the bottom half of each rib
and cut a slit in the top half.
Then, using a traditional drill,
they bore
tiny holes at specific points.
Taking one bundle at a time,
they string the ribs together
through the uppermost hole
and insert them into slots
of a hand-carved wooden hub.
Then they tighten and tie off
the string
to retain the ribs in position
and provide a pivot
on which the ribs can move
up and down.
Next, they attach the scaffold,
a smaller hub
with shorter ribs strung on it.
They insert a scaffold rib
into the slit of each frame rib,
then attach them by threading
a string
through the aligned holes.
The result?
Raising and lowering
the scaffold
moves its ribs along the slit --
pushing the frame ribs up
to open the umbrella,
or pulling them down
to close it.
With the umbrella open now,
they thread more string
through holes in the frame ribs
and loop it into
a spider-web-type pattern.
This produces a sturdy base
to support
the umbrella's paper skin.
After mounting the frame
on a wood and bamboo
umbrella handle,
they wrap two lines of string
along the frame perimeter.
This will support the paper skin
at the edge of the umbrella.
They make the paper from
the bark of the native saa tree.
The first step
is to soften the bark
by soaking it in water
for about 12 hours,
then boiling it
for another three or four.
Next, they mash it
with wooden mallets
for about an hour,
turning it into pulp.
They bleach the pulp and wash it
again to remove the bleach.
Only then is the pulp ready
to become paper.
They dump the pulp
in a large basin of water
and stir
so that it floats in suspension
while they move a plastic screen
through the water,
catching enough floating pulp
to coat the screen
in a thin layer.
They lay the screen
out in the sun
for three to four hours
until the layer of pulp
dries into a thin, fragile sheet
of paper.
They cut the sheets
to the shapes required,
then saturate each piece
with glue made from cassava,
a tropical root vegetable.
After applying a circular piece
around the hub,
they glue pie-shaped pieces
onto the rest of the frame.
Once they cover
the entire frame,
they repeat the process
to add a second layer.
They fold
all the pie-shaped pieces
over the end to thicken
and, thereby, reinforce
the edge of the umbrella.
After about four hours
out in the sun, the glue dries,
bonding the now stiff
and strengthened paper
securely to the frame.
They apply
three coats of oil paint,
allowing four hours
of drying time between coats.
This is a key step
because aside from providing
the background color,
the oil paint waterproofs
the paper.
Next, they varnish the handle
to make it moisture-resistant.
And now for the grand finale --
an artist paints a design
in vibrant waterproof oils.
The themes are traditional --
flowers, animals,
landscapes, people.
No stencils to trace
or patterns to follow --
the artist works
entirely freehand,
the result being
that no two umbrellas
are ever exactly alike.
Each oil paper umbrella
is a portable work of art.
Pretty yet practical,
rain or shine.
Narrator: The most-used fuel
for producing electricity
in the world today is coal.
Power plants burn it
in their furnaces
to heat water into steam
that spins giant turbines
which generate electricity.
At least 40%
of the world's electricity
is produced
by coal-fired power plants.
Coal developed
from prehistoric vegetation
that wound up buried underground
due to geological changes.
Over millions of years,
these decayed plants transformed
into combustible rock.
This is why we refer to coal
as a fossil fuel.
Coal runs in seams
through other rock layers.
Miners drill holes
through the seam
at several locations,
then mix together
ammonium nitrate and diesel
and pour a precise quantity
of this liquid expl*sive
into each bored hole.
The plug the holes with dirt to
contain the upcoming expl*si*n.
This directs the force
of the blast sideways
so that it'll fracture rock
as much horizontally
as vertically.
They place a blasting cap
in each plugged hole,
then connect
all the blasting cap wires
to detonation lines
through which they'll send
an electrical charge
to ignite the expl*sives.
They install detonation delays
to time the blast
one after another
because successive explosions
have greater impact
than simultaneous ones.
The blast dislodge
and break up the layers of rock
between the surface
and the coal seam deep below.
Workers clear away
the rocks and dirt
with a mammoth machine
called a dragline.
Removing the blasted rock
and dirt exposes the coal,
which is still
a solid, hard seam.
The side of the mine pit
shows how much rock is on top
of this particular coal seam.
Once miners blast
and clear away that rock,
they drill and load the holes
to set off more expl*sives
to fracture
the coal seam itself.
Then front-end loaders load
the coal
into specialized trucks
called coal haulers.
In one trip, a coal hauler can
transport about 220 tons of coal
out of the pit
to the coal stockpile.
From there,
railcars transport the coal
to the nearby power plant.
When this company prepares
to mine an area,
it removes the topsoil
on which vegetation grows.
As part
of a land reclamation program,
the company stockpiles
the topsoil
until it finishes
mining out the coal.
Then it refills the pit
with rock and dirt
it blasted away,
returns the topsoil,
and plants native vegetation.
The power plant is situated
by a man-made lake,
the water source for the steam
with which it generates
electricity.
When the coal arrives,
crushers grind it up
into baseball-sized pieces.
After a strategic blending
of different grades of coal,
to optimize heat output,
the coal travels by
a conveyor belt to indoor silos.
Each silo feeds crushers, which
pulverize the coal into powder.
Now the coal is ready
to fuel the furnace.
Meanwhile, huge intake pumps
draw lake water.
The furnace heats
the water to 1,000° fahrenheit,
well beyond the boiling point,
transforming it into
high-pressure steam.
The steam then enters
and rotates turbines,
generating electricity.
By the time
the steam exits the turbines,
it's thermally depleted
down to just 120° fahrenheit
and depressurized
to a vacuum state.
It then passes through
a condenser
containing cold lake water.
The water absorbs
the remaining heat,
converting the steam
back to water,
which is then recycled
into new steam.
The combustion process itself
creates sulfur dioxide.
The plant runs this gas waste
through vessels containing
a lime solution
to neutralize the sulfur.
This chemical reaction creates
water vapor,
which exits the plant's stack.
Wires coming off
the turbine generators
carry the electricity
to outdoor transformers.
The outdoor transformers convert
it to higher voltage
in order to have
less energy loss,
as the power from coal travels
through transmission lines
to some 350,000 households.
Narrator:
When you're traveling by air,
you want to be sitting
in a comfortable seat.
Private aircraft take comfort
to a level
far above that
of commercial airlines
with seats
that are as cozy and luxurious
as fine furniture.
They must also be lightweight
and fire-resistant.
On private
and corporate aircraft,
it's all about luxury seating.
Armchairs often swivel
and, at the push of a button,
recline
with an extending footrest.
The cushions are constructed
from layers of fireproof foam
containing carbon fiber
for optimum support
and durability.
Workers cut the cushion pieces
using a band saw
with a round blade
that slices through foam
without tearing or shredding it.
They spray adjoining surfaces
with water-based contact cement
and assemble them.
The assembly combines
different thicknesses
and three different densities
to make the cushion soft
in certain areas
and rigid in others.
The densities are color-coded.
After letting
the glue dry for 12 hours,
workers begin the final shaping.
This is
the seat-cushion assembly.
They first saw through it
laterally
to make the right thickness.
Then they temporarily adhere
a plastic template
of the final cushion shape,
trace it, then saw
along the trace line.
Next, using the technical
drawing as a guide,
they mark, then grind
the cushion's rounded profile.
Holding the next layer of foam
over the edge,
they verify the shape
with another template.
Then with yet another template,
they mark lines
for the cushion's creases
and, with a foam saw,
cut them two inches deep,
just enough to insert
velcro strips,
the backsides of which they glue
to the foam
with water-based contact cement.
Workers construct
the backrest cushion
just like the seat cushion --
assembling foam pieces
of different thicknesses
and densities,
shaping the perimeter,
grinding the edge profile,
cutting and velcroing creases.
Then they apply a final layer
of soft foam, 1/2 inch thick,
folding the edges onto
the velcro inside the creases.
They do the same with the seat
cushion, armrests, and footrest.
All the foam cushions
are now ready to be covered
in genuine leather.
In accordance
with safety regulations,
the supplier rendered
the leather fireproof
by treating it
with a calcium-based solution.
Seamstresses trace patterns
for the cover pieces,
then cut them out.
They line the perimeter
of each piece
with double-faced tape...
...fold over the edges
to create a neat hem...
...and trim the corners flat.
Then they sew on velcro strips
where required.
Finally, they assemble
the pieces into covers,
sewing an identification label
on each one.
They hammer every seam flat
to prevent bulges.
Then they sew
what's called a french stitch,
a line of straight stitches
on either side of each seam.
Meanwhile, workers glue
fireproof polyester batting
to the foam.
This layer
between foam and leather
will even out the surface.
They tear the perimeter
of the batting to thin it out.
Finally, it's time to dress
the cushions in their covers.
Workers use a metal rod
to help push the leather
deep into the creases
without bunching up.
Velcro strips on the cover
adhere to the velcro strips
inside the creases.
The covers also have
velcro closures,
and certain cushions have
velcro strips on the bottom
which attach
to the seat structure.
Once all the covers are on,
workers can complete
the seat assembly.
They attach the armrest
to the structure with screws,
then install the footrest,
which attaches with velcro.
It contains a cavity
for storing the life vest.
The seat cushion also attaches
with velcro.
The passenger seats
and pilot seat
are constructed the same way,
except for the pilot seat
often has a sheepskin insert
on the sitting surface
to absorb sweat
and keep the pilot
cool and comfortable.
Narrator:
It was the ancient romans
who first began
using cremation urns.
Today the custom continues.
The remains are stored in urns
permanently
or sometimes temporarily
before burial.
And with cremation,
one's final resting place
doesn't have to
be six feet under.
The cremation urn has
an important place
in some households.
It's a constant reminder
of the dearly departed,
helping to keep
the memories alive.
The urn starts with a concept.
The potter draws
a large-scale design,
which he'll use as a reference
as he shapes a prototype urn
from clay.
He slaps a lump of clay
onto the potter's wheel.
The wheel spins,
and the potter begins
to transform the shapeless lump
into the desired form.
The process is called throwing,
a potter's term for shaping.
He leaves the bottom open
so the walls can be more easily
formed into the desired shape.
He'll add
a base to the urn later.
As he pulls up the clay
to produce the walls,
he works it
to a uniformed thickness.
He gathers top
to narrow the opening,
a technique known as collaring.
Then with the potter's wheel
at a stop,
he takes the shape from round
to rectangular
and tapers it at the neck.
Then it's into a casting box,
which exposes
only half of the urn prototype.
He brushes
a release agent onto that half.
Using a mixer, he whips up
a mix of plaster and water.
He blends it until it thickens
to the consistency
of pancake batter.
The liquefied plaster
will harden in minutes,
so he quickly pours it
into the box
with the urn prototype
and fills it right to the top.
As the plaster hardens,
the exposed urn prototype makes
an impression of half the urn.
He'll make
another one exactly like it
for the other half of the urn.
He'll attach them
with a key system.
For this, he drills notches
in one mold half.
The notches match up
with raised areas
on the other mold half
to align them.
He ties the molds together
with suspender-like straps,
cinching them tightly together.
He adds a base to the urn
and straps it
to the other two pieces.
He sets
the assembled mold upright,
exposing the opening of the urn.
He's now ready to make a copy
of the original urn.
In fact, he'll make 20 at once
using 20 identical
plaster molds.
He pumps liquid clay into each
one, filling it to the brim.
Over three to four hours,
the plaster absorbs water
in the clay
it comes into contact with,
causing it to solidify.
The clay in the center
remains liquid.
He pours that into a barrel
to be strained and reused.
And now the big reveal --
he opens the mold
and removes the urn.
It's exactly like the prototype
sculpted by the potter.
He lifts a lid
from another plaster mold
and checks the fit to the urn.
After drying
and an initial firing
to harden the clay,
a worker coats the urn
and lid with a glaze,
working from the inside out.
The glaze is a mixture of finely
milled minerals and water.
It adds color and
a glass-like nonporous surface
when fired a second time.
Cremation urns come
in a range of styles and colors.
Customers often make a selection
that reflects
the taste of the deceased.
Another worker now brushes
a mixture of wax and alumina
onto the neck of the urn
and lid.
This will keep them
from fusing together
during the final firing.
They fire the cremation urns
at a very intense
for about 15 hours.
This transforms the clay
into a durable ceramic.
They cool the urns slowly for
Four days in the making,
these urns are now ready
to contain a loved one's remains
and, in so doing, honor a life.
If you have any comments
about the show,
or if you'd like to suggest
topics for future shows,
drop us a line at...
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