Answers to Questions Kids Ask! - Where "Why?" Turns to "Wow!"
Glass has been made by humans for about 4,500 years, and it generally consists of silica (sand), potassium or soda, lime, and occasionally some other chemicals. They are melted together and cooled at air temperature so that the material is hard, but has a smooth and flowing shape, more like a liquid. The precise recipe for glass changes from place to place — the chemistry and techniques are often closely guarded secrets.
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Word of the Daystatecraft:
statecraft: the art of government and diplomacy.
Born on this dayFebruary 20, 2017
1925 - Robert Altman
1927 - Sidney Poitier
1940 - Jimmy Greaves
1946 - Brenda Blethyn
1951 - Gordon Brown
1958 - James Wilby
1961 - Imogen Stubbs
1966 - Cindy Crawford