When we buy something, usually we look at its appearance, its quality and its cost (the result) without looking at the production of it (the process). Have you ever thought that we usually buy and use many tools but we do not care how it is made? For example, the glass. Dou you know how the glass is made?Generally, this is three steps of producing the glass:
First, gathering the materials for making glass. The materials are sand, limestone, flint, spar, or some other silicious substances, with one or other of the fixed alkalies, and in some cases with a metallic oxide. The silicious substances are lead, borax, arsenic, nitre, or any alkaline matter such as soda, pearlash, sea-salt, and wood-ashes.
Second, processing the materials. The coarse goods must be washed in water. Then it must be reduced to powder. After sifting out the rough parts, the proper proportions are mixed together and put it into the calcining furnace, where they are kept in a moderate heat for 5 or 6 hours, being frequently stirred about during the process.
Third, forming the glass. The molten glass from the furnace is divided into two places with two purpose; making plate glass and making bottle glass. To make plate glass, the molten glass is flattened and cooled by rollers, and the result is thin plate glass. At the other place, to make bottle glass, the melted glass is flowed into the removable mould then blown by air. The glass is cooled, and the shell is removed, then the result is bottle glass.
Now we know the production of glass. Do you know how you were made by God?
Nurfitri Anbarsanti
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