Glass fibers are extremely strong; for their weight, they are stronger than steel. They are made by forcing molten g lass through tiny holes called spinnerets.

Glass fibers are extremely strong; for their
weight, they are stronger than steel.
They are made by forcing molten g lass through
tiny holes called spinnerets. As many as four
hundred spinnerets are placed together, and
threads of glass much thinner than human hairs
are drawn off at great speed-miles of thread
per minute. As they speed along, the threads
are coated thinly with a type of glue and
twisted into a yarn.
The glass fibers are used with plastics to make
boats and car bodies. They are also woven into
heavy cloth for window draperies and into
strong belts for making tires stronger.
A special kind of glass fiber is causing a
revolution in communications. A signal of light
can be made to travel along the fiber for very
long distances. By changing the quality of the
light, many messages can be sent at once along
one strand of glass. New office buildings are
being wired with glass fibers as they are built.
The glass fibers will be used to connect
telephones and computers in ways that not
long ago were either impossible or too
expensive.
Glass wool traps air in a thick, light blanket of
fibers. This blanket is then put into walls and
ceilings to keep warm air in during the winter
and coo l air in during the summer.
To make glass wool, molten glass is fed into a
spinning drum with many holes in it. As the
glass threads stream out of the holes, they are
forced downward by a blast of hot air and
through a spray of glues. The threads are then
further blown about to mix them up as they fall
in a thick mat o n a moving belt.
The glass we see thro ugh and drink out o f has
many, many other uses besides the ones
described here.