In a message dated 5/20/99 5:18:06 PM Pacific Daylight Time,
Fred_Katz@ci.sf.ca.us writes:
<< I always thought it was a liquid. I seem to recall learning that old glass
panes get thicker at the bottom as time passes, due to gravity's effect and
the liquid nature of glass. >>
I remember reading that this is a misconception...that the reason old glass
is thicker at the bottom is not because it is liquid, but because of the poor
quality of glass back in the days. And also because glass-forming technology
back then wasn't as good as today. I forgot the specifics, but what I read
did make sense. But I was also taught that glass is a liquid too.
Uh oh..time to dig through old class notes...?
Van
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