Section Three: Reading Comprehension

Questions 1-9


Glass fibers have a long history. The Egyptians made coarse fibers by 1600 B.C., and


fibers survive as decorations on Egyptian pottery dating back to 1375 B c. During the


Renaissance (fifteenth and sixteenth centuries A.D.), glassmakers from Venice used glass


Line fibers to decorate the surfaces of plain glass vessels. However, glassmakers guarded their


(5) secrets so carefully that no one wrote about glass fiber production until the early


seventeenth century.


The eighteenth century brought the invention of "spun glass" fibers. Rene-Antoine de


Reaumur, a French scientist, tried to make artificial feathers from glass. He made fibers


by rotating a wheel through a pool of molten glass, pulling threads of glass where the hot


(10) thick liquid stuck to the wheel. His fibers were short and fragile, but he predicted that


spun glass fibers as thin as spider silk would be flexible and could be woven into fabric.


By the start of the nineteenth century, glassmakers learned how to make longer, stronger


fibers by pulling them from molten glass with a hot glass tube. Inventors wound the


cooling end of the thread around a yarn reel, then turned the reel rapidly to pull more fiber


(15) from the molten glass. Wandering tradespeople began to spin glass fibers at fairs, making


decorations and ornaments as novelties for collectors, but this material was of little


practical use; the fibers were brittle, ragged, and no longer than ten feet, the circumference


of the largest reels. By the mid-1870's, however, the best glass fibers were finer than silk


and could be woven into fabrics or assembled into imitation ostrich feathers to decorate


(20) hats. Cloth of white spun glass resembled silver; fibers drawn from yellow-orange glass


looked golden.


Glass fibers were little more than a novelty until the 1930's, when their thermal and


electrical insulating properties were appreciated and methods for producing continuous


filaments were developed. In the modern manufacturing process, liquid glass is fed


(25) directly from a glass-melting furnace into a bushing, a receptacle pierced with hundreds


of fine nozzles, from which the liquid issues in fine streams. As they solidify, the streams


of glass are

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