We may think of glass as being produced by the mixture of some very special chemicals in a very special way, a sort of miracle of chemistry. But actually, glass is made by a rather simple process using quite ordinary materials. Glass is a substance made by “fusing”(melting together) certain materials, and then cooling the mixture so that the atoms arrange themselves in an unorganized pattern. What materials? Well, about 95 per cent of the raw materials in the earth could be used in making glass! The most important materials used in making glass, however, are: sand (silica), soda, limestone, borax, boric acid, magnesium oxide, and lead oxide.

Nature herself produced the first glass. About 450,000,000 years ago molten(melted) rock in the core of the earth forced its way to the surface and broke through the earth’s crust in volcanoes. When the hot lava contained silica and cooled rapidly, it formed a glass as hard as a rock. This volcanic glass is called obsidian.

Glass has been made by man since very ancient times. The Egyptians, more than 5,000 years ago, knew how to make a kind of colored glass with which they covered stone and pottery and sometimes made into beads. Perfume and ointment bottles made of glass were used in Egypt more than 3,500 years ago.

The Roman Empire (lst century B.C. to 5th century A.D.) was one of the greatest periods in the history of glass. It was at this time that man learned how to blow glass and thus form hundreds of different shapes and sizes of glass objects.

Today, of course, there are many new ways of making glass that have been developed. But this is the basic process. The raw materials for glass are brought to the glass factory and stored in huge bins. The raw materials are carefully measured and then mixed into a “batch.” Then broken glass of the same formula, called “cutlet,” is added to the batch to speed the melting. The batch is fed automatically into the furnace. The glass then flows out of the furnace at lower temperatures.

Then the glass goes through many processes such as blowing, pressing, rolling, casting and drawing-depending on the type of glass that is being made.

Glass blowing is one of the oldest of skills. But as modern machines have been developed and perfected, and as the use of glass has increased, glass blowing by hand is becoming rarer and rarer.

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