Danny Warren, age 13, of Lebanon, Tenn., for his question:
What is fiberglass?
This marvelous material was invented in the last century, and in 1893 a lady's dress woven from fiberglas and silk was put on display at the Chicago Exposition. But industry did not figure a way to make fiberglas cheaply enough for it to become popular until the 1930s. Nowadays it performs a thousand duties in our daily lives.
No one could have thought of a better name for fiberglas. The amazing material is made of glass fibers. The idea of a textile material woven from glass is hard to believe. Textiles are woven from pliable materials, and the glass we see around us is hard and brittle and absolutely unbendable. But this unyielding everyday glass comes in fairly thick flat sheets. Fiberglass is woven from threads often 15 times thinner than one of the hairs on your head.
Fiberglas cloth has all the good qualities of window glass plus a pliable quality all its own. It refuses to burn or rot, wrinkle or stain. It will not rust or mildew, stretch or sag. Its colors do not fade, and most acids do not corrode it. It is a splendid insulator for holding in the heat. It can be washed spanking clean, and it dries itself naturally as smooth as glass.
It is sad that industry has not found a way to make fiberglas textiles suitable for everyday clothing. But the fabrics have many other uses, and miles of durable fiberglas fabric are sold every day. It is used to make smooth hanging draperies and gauzy curtains. A tablecloth of fiberglas is a friendly work saver because catsup and other messy foods can be wiped away without leaving the faintest stain.
Glass is the basic material for making fiberglas, and the basic ingredients in glass are sand, lime and soda or potash. Other ingredients may be added to the recipe before the mixture is heated in a furnace to about 3,000 degrees Fahrenheit. The tacky brew is made into glassy marbles a little wider than half an inch. The marbles are inspected and those with flaws or bubbles are discarded. Those that pass the test are heated to melting point in a clean electric furnace.
The bottom of the furnace is riddled with tiny holes, and thin streams of molten glass run through in slender threads. Hundreds of these thin fibers are twisted together to make a yarn. The yarn is coated with a starchy substance and sent to the textile mill to be woven into fiberglas fabric.
Fibers of glass also are used to reinforce certain plastics for molding parts for planes, boats and cars. Foamy masses of glass fibers are used for electrical insulating and for sound proofing rooms, and fluffy pads of fiberglas wool placed in the walls help to hold in the heat. Fiberglas fabrics are made from long threads. Fiberglas wool and foam are made from short threads fluffed up by steam and matted together.