Hello All,
I remember reading an article about this in Scientific American a
while back. In the past people would say that glass is an amorphous <sp?>
solid. I think that this is kinda like saying that its a liquid with just
an amazingly high viscosity. It also has something to do with its crystalline
structure.. Not really a solid crystal lattice but not quite a liquid.
From looking at large panes of glass from, I believe, medival churches.
People noticed that they were all thicker at the bottom than the top. To
most this lended credance to the belief that glass was a liquid that was
very very very very slowly flowing downward. But, as Van pointed out, it was
determined that the most likely cause for this was that the windows were
set upright before the huge, thick, panes of glass had time to complety cool.
I believe the scientists, in the art.,looked very closely at older but
modern glass and
found no evidence of any type of flowing of the glass.
Funny how one set of bad data can spring forth a scientific belief
that everybody just believed and no one really bothered to challange untill
recently.
Daniel 69 2000
sometime physics instructor
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