Glass: A Transparent Substance
by Glass is a transparent or translucent substance. It is physically neither a solid nor a liquid. Although it is easily shattered, it is one of the strongest substances known. No one really knows when exactly the secret of making glass was first learned.
The chief ingredients of glass are certain types of sand, soda ash, or potash and lime. These materials are available all over the world easily. Any country could have stared making it.
According to tradition, the Phoenicians are the first ones to have learnt the secret of glass making. It seems some sailors used lumps of niter to balance their kettle on the fire. The heat melted the niter, which mixed with the sand on the beach and flowed out as a liquid stream of glass. We really do not know whether this story is true, but we do know that the Syrians were using glass 5000 years ago. They were the original makes of glass. Their merchants sold glass ornaments and decorative pieces in the Mediterranean countries.
It was the Egyptians who first blew molten glass to make glass vessels. They went one step further. They gave a red tint to the glass by adding copper to the molten mixture. Egyptians also mixed crushed quartz to sand to change the color. They soon learnt to make blue, green and purple colored glass by adding cobalt, and manganese to the molten glass mixture.
Later on the Romans too excelled in glass making. They used glass in thin sheets for wall coating. By the Christian era glass began to be used for windowpanes.
Wherever we look we see glass all around us. Windowpanes, tumblers, windscreens, bottles and decorative pieces. Even things like telescopes, microscopes, computers, TVs, and spectacles make use of glass.
Glass comes in different forms too. Sheet glass is the cheapest form of glass. Other types of glass are float glass, moulded glass, soda glass, flint glass, optical glass, stained glass and heat resistant glass. There is even bulletproof glass strong enough to resist machine gun fire.
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Post CommentIcyCucky
On August 28, 2008 at 7:17 am
Wow, this is wonderful to learn
swapna
On August 31, 2008 at 1:26 am
icy, thanks for ur encouragement….