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Glass is a liquid?
Quote from: dentstudent on 04/06/2007 08:30:47Glass is a liquid?Well That is interesting.. I don't recall ever paying attention to the dog and color blindness thing! Thanks Dr. Dick!No it isn't. This is a common misconception arising from various observations that didn't hold up. One observation was that the glass at the bottom of older windows is thicker than the glass at the top. Thus, the glass must flow down over time. The real issue is that older windows weren't made as uniformly as newer windows, and it's easier to hang a window with the heavier part on the bottom, so it' bottom-heavy, not top-heavy.Another is that glass rods bend over time, since if you have a stack of glass rods supported at the ends, by the time you get to the end of the stack, the rods are bent. Actually, there's selection going on as people take the glass rods - they prefer the straight ones, leaving the bent ones behind.In general, you have to be careful with these little tidbits of information that often circulate around the internet. They are often wrong. Another is example is the supposed color-blindness of dogs. Everybody knows that dogs are color-blind, right? Well, everybody is wrong. I remember hearing a vision expert on some podcast in the last year discussing this matter (I think it was NPR's "Science Friday", but I'm not sure).Dick
Ah, here we have a philosophical question about how old we really are. Most of our cells regenerate, and therefore much of our own bodies are not more than a decade or so old. With trees, the new growth goes onto the outside, a bit like a new coat, just under the bark, and so this part is only a year old. The further into the tree you go, the older it becomes, and so the only part that is 4767, is the very centre, ie., the first year it was alive.
You're a gentleman and a scholar!