We live in a
world of steel and concrete. Our structures, our machines and our jobs, are
built around these two fundamental parts of modern life. It is difficult to
imagine a world without these two materials. We would have no cars, cans, or
electronics. There would be no roads, foundations for buildings, or bridges. In
short we would be more primitive than our ancient predecessors; living out of
crude wood houses with mud or wood floors. Yet we have forgotten where all this
remarkable advancement came from. In fact we often look down upon this seeming
simple item as being as primitive as those huts and serving no more purpose to
people than a bow and arrow does anymore. If indeed they think of it at all,
they may think that it once was important but surely things like the car or the
radio were far more noteworthy. Thus it is looked over in museums, ignored at
gardening stores, but this simple little item built civilization. I speak of
course, of the simple ceramic pot.
It is the
tendency of people to think that clay pottery is simply mud that has been
shaped and baked in an oven or kiln. And while to a degree this is true, it is
far more than that. The material used for making pottery often called clay has
a simple enough make up. It uses either a carbonate of silicate based mixture with
various oxides and trace minerals that affect properties such as strength and
hardness. Mineral pockets like these run in the ground through veins in most
areas of the world. These minerals form tiny crystals in the shape of tiles.
The addition of water can loosen the tiles from each other allowing them to
slide over each other. It can them be molded and shaped as the artist pleases.
When it dries there is still a small amount of water left in between the
crystals and while this may not affect the pot when in ideal conditions, when
wetted there is still aa large enough gap between the crystals that it will
dissolve. Soon, people realized the clay could be baked to draw all the water
out. This caused the gaps to get much smaller blocking the water so the clay
would no longer dissolve. Now our ability to understand the molecular structure
of these ceramics has grown greatly. While people tend to think of them of
fragile, one of the hardest materials known to man, tungsten carbide, is a
ceramic and used in hundreds of items.
Then came the
discovery of glazes which is similar to a glass coating over the pot. It was in
this way that people discovered the secret to making glass. Soon people
realized that they could add minerals to the glaze to change the color
similarly to what they did with the clay itself and that when fired the glaze
would change color. As people continued to experiment with glazes sometimes
they would begin to see a bead of shiny metal form on the sides of their pots.
This was the origin of smelting. Certain metals make bright colors when used in
a glaze. Often when it was heated to a high temperature the metal oxides would
break their bonds and pool together at the bottom. Since metal is so much
heavier than its impurities, when it reaches its melting point, it runs down
and joins with other molten metal. Eventually metallurgy broke off into a
different art. It began with copper evolving into bronze. Soon furnaces could
melt iron and steel was born.
Long before
concrete was the preferred building material people used brick. Bricks, like
pottery, were once just make by packing mid into a mold and left in the sun to
harden. But like early pottery these mud bricks dissolved in water so could
only be used in dry arid climates. Also like pottery, they discovered that
firing bricks could make it resistant to water damage. As people experimented
further, concrete and mortar slowly evolved and often both were used together
with bricks. Fragments of pottery and straw were used as binding agents and
mortar was used to cement bricks in place. In a traditional idea that continues
to this day, brick is used for facing by creating two thin parallel walls. Then
a mixture of concrete and scraps of pottery and rocks are poured in the gap
making a strong water resistant wall. Whereas stone once had to be cut from a
quarry and transported to a site to be shaped, now stone could be molded in
place. At last the day came. Pozzolana was a roman concrete based on volcanic
ash. Most concretes at the time had to dry to cure but pozzolana didn’t cure by
drying. It cured by a chemical reaction similar to the way plaster can dry
underwater. This was one of the first great steps in concrete development. Now
foundation could be poured in the water. Columns and pillars could be cast
instead of cut and stacked. Modern concrete itself is not much different and
follows the same type of chemical reaction. In combination with steel bracing
like rebar concrete could be used to make beams and cables where stone could
never be used before. The concrete protects the steel; the steel holds the
concrete together.
Very few people
know this remarkable story and even fewer realize what it means to a world like
ours. The foundation of our technologically based world has its origins in a
hole in the ground, some fire, and a curious human. The influences of this
primitive art have wormed its way into every aspect of our electronic life. So
next you see a skyscraper, and see its impressive modern design of a concrete
skeleton, reinforced with steel, and panned with glass, think back to the
humble pot and it startling influence on a world we take for granted.
Ancient Greek Pottery
- Play-doh
- Clean soup can
- Black paint
- Greek Myths coloring book (has good stories and good designs)
- Roll the play-doh out into a long rectangle, very flat. Keep a little bit off to the side if you want to make handles.
- Wrap the play-doh around the soup can and mold it to the can.
- Create a handle for your pot. Mold it onto the pot.
- Have your mom put it into the oven at 100 degrees for about twenty minutes.
- After it cools, use black paint to put designs on your vase.
- Let the paint dry, then have your mom stick it in the oven for another twenty minutes.
- Now you have an antique vase!
