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From VOA Learning English, this is the Technology Report.
One hundred years ago, a new kind of cook container entered the American market. It was called Pyrex. Today the Pyrex name remains well known in the United States. The heat-resistant glass products are still being manufactured. And early Pyrex products are now considered collector’s items, something people keep because it has value.
Heat-resistant glass was invented in Germany at the end of the 1800s. The glass was used mostly in lanterns because the lighting produced heat. It also was used in containers for telegraph and telephone batteries, to help provide electricity. The usefulness of heat-resistant glass as cookware was discovered by accident. It started at the Corning Glass Works manufacturing company in New York. A scientist working there gave his wife a battery jar made of borosilicate glass. Borosilicate glass is resistant to heat and very strong. Kelley Elliott is with the Corning Museum of Glass. She says the scientist’s wife used the jar while cooking, and noted something unusual. She baked a cake, a sponge cake, in this battery jar. Ms. Elliot said the woman discovered “that the baking was much more efficient, and much more even than baking in ceramic or metal was.” Ms. Elliott adds that when Pyrex products began appearing in U.S. stores in 1915, the cookware quickly became popular. At first, Pyrex dishes were only made of clear glass. But the Corning Glass Works soon produced dishes in colors. Borosilicate glass is also being used for astronomical instruments because the material is not affected by temperature changes.