and faster, then-- flap! that whole side flies open, and what was a
globe is a disk, or wheel, four or five feet in diameter. It is called
a table. After annealing, it is cut up into panes.
"There is another process," continued the
gaffer, "by which our common window-glass is made. By the way, if you
visit Pittsburg, in Pennsylvania, you must go into the window-glass
factories there; you will find them very curious. Their furnace, in
the first place, is built in the ancient style: it has no chimney, and
the smoke from the bituminous coal they burn pours out in a cloud into
the room. There are openings in the roof for it to escape through,
and a continual draught of air from the doors carries it upward, so
that it is not so bad for the workmen as one would think. Besides,
they do not begin to blow until the smoke is all burnt off.
"There are five pots on each side of the furnace;
and you will see five men in a row, blowing all at once, with the
regularity of a file of soldiers exercising. Each gathers thirty or forty
pounds of metal on his pipe, which is very long and strong. They stand on
platforms, to get room to swing the glass, as they blow it. The five men
begin to blow and swing all together. Each blows a great globe of glass,
which is stretched out gradually by the swinging motion into a cylinder,
or roller, as it is called, five feet long. Then the five rollers are swung
up towards the furnace-holes, and five other soldiers spring forward with
their guns,-- which in this case are iron bars, that
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