Glass & Glass-Making
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and bring back images of the aristocratic homes that survived the
LUMPS OF CULLET, OR RAW GLASS
Glass in the Making
Before sand is melted for the making of glass
it is first cleansed of impurities. If a fine quality of glass is
to be obtained, the sand is purified by washing, burning and sifting.
In this way it is rid of iron, lime, chalk, magnesia and dirt that
would affect its quality. When the sand is cleaned, "the batch" is
made by skilfully mixing the ingredients of glass in their proper
proportion. The mixture is then poured into melting pots of carefully
selected clay, or into gas-heated "tank furnaces."
Molten glass is so sticky that it will adhere
in a soft mass to the end of a stick, "and if the stick be a tube, the
lump may be distended, by blowing through the tube, into a hollow
The form of this sphere or bulb may be modified by
manipulating the pipe, and if a second iron be attached by a seal of
glass to the other side of the bulb, it may be drawn out into a tube.
If the bulb be opened by removing it from the blowing iron, and then,
after attaching it at its opposite side to another iron, be trundled
rapidly like a mop, the opening will expand by centrifugal force,
into a disk.
These are the processes which, infinitely diversified
and complicated by the skill of the workmen
MIXING THE BASE OF SAND, SODA AND LIME
Broken bottles are fused with the sand
and alkalis to obtain a clear glass