Glass is a super-cooled liquid and flows even more slowly than pitch.
The observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries. The assumption being that the glass was once uniform, but has flowed to its new shape, which is a property of liquid.[41] However, this assumption is incorrect; once solidified, glass does not flow anymore. The reason for the observation is that in the past, when panes of glass were commonly made by glassblowers, the technique used was to spin molten glass so as to create a round, mostly flat and even plate (the crown glass process, described above). This plate was then cut to fit a window. The pieces were not, however, absolutely flat; the edges of the disk became a different thickness as the glass spun. When installed in a window frame, the glass would be placed with the thicker side down both for the sake of stability and to prevent water accumulating in the lead cames at the bottom of the window.[42] Occasionally such glass has been found thinner side down or thicker on either side of the window's edge, the result of carelessness during installation.[43]
Also from the same article
Laboratory measurements of room temperature glass flow do show a motion consistent with a material viscosity on the order of 1017–1018 Pa s.[39]
So it does flow, but so slowly that it may as well not
The notion that glass flows to an appreciable extent over extended periods of time is not supported by empirical research or theoretical analysis
Wrong!
Aso from the same article which precede the words that you quote:
livin the dream, livin the dreamFind something incredibly boring, then argue about it! That's the life!
hmmmm suppose... but i tuned out after the, for me, heyday of the 80's
I watched seriously up until about 10 years ago, .....
I thought you meant the pitch at first!
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