HISTORY OF GLASS
The origin and use of glass goes
back almost 5,000 years.
Archaeologists have discovered
evidence of glass objects dating
as early as 3,000 B.C. The
ancient Greeks used glass in
their buildings. Historical
records from the period refer to
baths and rooms lined with
glass. Window glass dates from
the end of the third century.
Experts believe that the ancient
Syrians discovered glassmaking,
probably by accident, about
3,000 B.C. A manufactured green
glass rod found in ancient
Babylonia (modern Iraq), dates
to 2,600 B.C. Syrian glass was a
simple melted mixture of soda
ash, lime and sand. Glassmakers
formed it into final shapes by
sculpting it while still hot.
When Egypt conquered Syria in
1,400 B.C., the captured Syrian
glass workers were sent back to
Egypt. They refined glass making
into a higher art. Glassworkers
produced vessels, vases and
eating utensils by pouring
several thin layers of molten
glass into sand molds in the
shape of the object. The
glassware was decorated by
adding molten colored glass
drips to the final layer.
The Egyptians discovered that
they could blow a gob of molten
glass from the end of a hollow
metal tube into the mold. This
technique evolved into what we
now know as glass blowing. Glass
blowing remains a useful
technique for creating many
types of glassware.
Window glass originated in Rome,
but it was very thick and
translucent. That is, it let
light in but people couldn't see
out. In 1291, on the Italian
island of Murano, workers
developed a clear, almost
transparent glass called "cristallo."
This is where the word "crystal"
comes from. Murano glassware
became popular throughout
Europe, and Italy built up a
thriving export trade.
In the Middle Ages, glass making
was still a hand-made process.
Window glass was made by blowing
the molten glass into a flat
disc which was then spun so that
centrifugal force caused the
glass to thin out and flatten.
These discs were cut into small
panes of glass, usually limited
to 18 square inches. Glass
workers searched for
improvements.
Cylinder glass was one such
improvement. The molten glass
was blown into a cylinder which
was cut apart, then reheated and
flattened. In the 16th and 17th
Centuries, the English
discovered that using coal
instead of wood in their
furnaces produced a much clearer
glass. Although the panes were
wavy and full of bubbles, and
sometimes light amethyst or
amber in color, people could
actually see through their
windows.
Louis Lucas de Nehou, a
Frenchman, developed a manual
process for making plate glass
in 1688. The method was
cumbersome-it took 16 days from
start to finish and produced
glass so expensive that only the
very rich could afford it. For
the next two hundred years,
improvements were made in this
process, primarily in the power
sources needed to melt the raw
materials into glass, and in
methods to increase the amount
of glass that could be produced.
But the French plate glass
method remained the basic
technique. Finally, in the
1900's, technological
improvements were developed
which made possible large scale
glass manufacturing as we know
it today.
See... Types of Glass
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