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CHEMISTRY
Fact or Fiction?: Glass Is a (Supercooled) Liquid
Are medieval windows melting?
By Ciara Curtin on February 22, 2007
Fact or Fiction?: Glass Is a (Supercooled) Liquid
Credit: Bill Heinsohn Getty Images
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In medieval European cathedrals, the glass sometimes looks odd. Some panes are thicker at the bottom than they are at the top. The seemingly solid glass appears to have melted. This is evidence, say tour guides, Internet rumors and even high school chemistry teachers, that glass is actually a liquid. And, because glass is hard, it must be a supercooled liquid.
