In a message dated 5/21/99 6:27:15 PM Pacific Daylight Time,
WayneLoom@aol.com writes:
<< Glass is generally accepted as "almost" a fourth class of matter but I
can't
remember what it is called. My esoteric chemistry is slipping. Glass is
neither liquid nor solid because it displays some propeties of both. Glass
actually continues to flow throughout its lifespan as evidenced by the
distortion old window panes. If this concept has changed in the last 30
years I am unaware of it. >>
Hmmm...wouldn't that be plasma?
I was also taught that glass was "supposed" to be liquid because old windows
tend to be thicker at the bottom...but then I recently read something from
more than one reputable source that basically debunked that theory. It all
had to do with the poor quality of glass and of the methods of production
back then. It also helps to design the bottoms of such large glass panes
larger than the top in order to sustain the weight. What they shoulda done
back then was make a note as to whether the thickness discrepancy was
accidental or not. Then we can compare those notes to our measurements today.
Oh well, only one way to settle this now: we'll take some more measurements a
few hundred years down the road and see how they compare to ours! :)
Van
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