glass is liquid, david is wrong

I was raised to believe glass is liquid not solid. I’ve even used this fact to swindle some mensa goons. but to my astonishment, when i read http://www.straightdope.com/mailbag/mglass.html , SDSTAFF David said ‘Before I tackle your question, I want to make something perfectly clear to everybody reading this. Glass is not a liquid! It is an amorphous solid. Deal with it, folks’.

now, normally i would let this kind of impudence slide, but i feel that statement was a direct attack on us pro-liquids.

i would like to quote uncle cecil himself in http://www.straightdope.com/classics/a1_120.html
‘Despite its appearance, glass is really a highly viscous liquid rather than a solid, and you can see through it for the same reasons that you can see through water.’

now if david would just let me know how he likes his crow, i would be satisfied.

thank you, goodnight

Cecil says it would take “billions of years” for glass to flow visibly. The difference between that and “amorphous solid” is merely one of definition.

And, of course, liquidity has nothing to do with transparency. Diamond is most definitely a solid, and also most definitely transparent.


John W. Kennedy
“Compact is becoming contract; man only earns and pays.”
– Charles Williams

Old myths die hard.

You might check out the following threads that have already dealt with your complaint:

Glass not a liquid? in this forum

Melding Glass (Cecil weighs in) in the General Questions forum, where Cecil admits that his earlier column was based on earlier (mis)understanding about the nature of glass.

Sorry, Metro, you’re gonna have to give back whateve money you swindled from the mensa goons… if they can find you.

Ahem.

If you will check the earlier thread on this mailbag item, you will find that this has already been discussed. You will also find a link to a thread in General Questions in which Cecil himself appeared to note that I was right. So I suggest you serve up a nice helping of that crow for yourself, for I will not be having any.

The earlier thread mentioned above is below: http://www.straightdope.com/ubb/Forum6/HTML/000127.html

oops, sorry for the re-thread. i myself like crow pot pie.

errr, i was talking about the other kind of glass. you know the liquid kind. you probably can’t see it because it’s invisible.

by the way, how do ya’ll find old threads like that. i tried to search but couldn’t turn anything up.

An unsolicited theory:

The real reason people attach themselves to theories like “glass is a liquid” is that they are so counterintuitive. People like bludgeoning each other with counterintuitive ideas that are true, according to some old canard, and the ideas spread like wildfire. Glass is obviously a solid, and fit the scientific definition of a solid (it is no more a liquid than wood, people, or any other non-crystaline substance), thus it must be a liquid. Scientists don’t know how bees can fly; the ozone layer is three milimeters thick; trees pollute.

If your senses tell you one thing, and your science textbook tells you the same thing, the kid one year older than you in school will assure you the opposite.

Ooops! Almost forgot my favorite: time doesn’t exist.
Me: Why not?
Older kid: Because there is no time!
Me: Why not?
Older kid: Because no human measure of time is perfect.
Me: What’s that got to do with anything?
Older kid: There is no time; it’s just obvious.

Boris said:

Hmmm. Maybe; I dunno. I think it’s just the “I know something you don’t know” syndrome. They heard somewhere that glass was a liquid, and so they flaunt it around as an example of knowledge that runs, as you say, counterintuitive to what one would otherwise think. Ah, hell, who am I kidding? I have no idea why people spread this stuff! :slight_smile:

You were doing ok 'til you mentioned this one. In fact, trees do pollute. They put out hydrocarbon emissions – some in fairly decent quantities. Now, are they worse than, say, factories? Or as bad as Ronald Reagan said they were (when he was governor of California)? No. But they do “pollute” and do have to be taken into account in models trying to show how ozone smog is formed and where it goes.

Yeah, okay, I guess it hinges upon your definition of pollution. I don’t consider volatile organic compounds to be a pollutant, because I have never heard any evidence of bad effects of VOCs alone. They only create ozone in the presence of nitric oxide and nitrogen dioxide, neither of which has large natural sources (lightning storms notwithstanding). I’m just very skeptical when someone says “trees pollute” without also saying “bakeries pollute” and “dry cleaners pollute” in the same paragraph.

Trees also “de-pollute” (neologism) by absorbing carbon dioxide. So I would say their net effect on pollution is negative, although I know it would be hard to get everyone agree to a single quantity for “total pollution”, since you would be adding apples to oranges, so to speak.

I meant to say, I don’t know of any bad effects of VOCs alone in the atmosphere. I didn’t mean VOCs carried into water supplies by paint spills or anything.

Boris, if we’re going to go much further with this (having nothing to do with glass :slight_smile: ), we should probably move it. That said, here is my response < grin >

While everything you said is pretty much true, that doesn’t mean VOCs aren’t pollutants. Illinois (and many other states) has rules several inches thick about emitting VOCs into the atmosphere. Ya gotta figure that means they are considered pollutants. :slight_smile:

Also, there are other NOx “natural” sources, such as bacteria in the soil. These have been incorporated into the latest pollution models.

Well, most people probably don’t realize that bakeries pollute. Duh – what do you think that “great smell” is when you pass by? Sorry, personal grudge that I won’t detail here.

That aside, while I understand what you’re saying, it is possible to make a true statement without also making every other associated true statement along with it. I can say, “Clinton is a liar” without having to also say, “Nixon was a liar.” In fact, I hate people who argue that way. There is a rabid Republican lawyer here at work who would do that. If I’d make a comment about Dan Quayle, he’d make one about Marion Barry. Well, since I’m not a Democrat, I don’t really care about Barry, and it doesn’t disprove whatever I said about Quayle. Likewise, saying, “Trees pollute” doesn’t have an impact on whether bakeries or dry cleaners pollute, but it runs both ways. The fact that bakeries and dry cleaners pollute does not negate the fact that trees do, in fact, pollute as I’ve already described.

Precisely. What applies to CO2 has nothing to do with what applies to VOCs.

Incidentally, that “precisely” was meant to apply to your last thought, not your first, in that quoted bit. I would not state that they have an overall net effect either way for precisely the reasons you gave.

Metro asks: << by the way, how do ya’ll find old threads like that. i tried to search but couldn’t turn anything up. >>

Well, see, there’s a secret to it. Basically, I know it exists, and so I just go looking through each goddam page of the old stuff for however many past days it takes, until I find it. It’s the non-computer method.

Okay,David B, your points are well-taken. When I was speaking of my skepticism of the “trees pollute” crowd, it was because it often comes when people are trying to explain why we don’t need to regulate something. “Trees pollute, trees can’t be regulated, so we don’t need to regulate anything else.” The same goes for volcanoes: “volcanoes put chlorine in the atmosophere, aerosol propellants put chlorine into the atmsosphere; the ozone layer survived volcanoes, so the ozone layer can survive aerosol propellants as well.”
And, while I’m getting this off my chest (with apologies to this thread), there was one that went a little like, “Sulfur emission regulations are bad for agriculture, since sulfuric acid and nitric acid are both found in acid rain, and nitric acid is good for crops.” This wasn’t water-cooler gab, this was the analysis a bunch of my classmates had of a reading we did on acid rain regs.

A factoid can contain a grain of truth, but the fallout from the factoid tends to mislead. I just don’t want people believing what Reagan wanted them to believe, i.e., that if we let the environmentalists have their way they’ll cut down all the trees.

Dex said:

Funny, that’s the exact way I do it! High-tech, eh?

Maybe I’m too young to remember this, but when was glass considered a liquid? What the heck was the argument for that?!

Momotaro:

Look at the glass in the windows of an old building. A medieval cathedral will suffice. Notice the the individual pieces of glass in the windows are thicker at the bottom than the top. Conclude that the glass has started to seep downward like a thick liquid.

This works if you ignore the fact that craftmen of that day had no technique for making perfectly flat panes of glass. Every piece of glass they used was thicker on one end than the other. It was standard operating procedure to glaze the window with the thicker part at the bottom, in the belief that this would be a more stable configuration.

Dr. Fidelius, Charlatan
Associate Curator Anomalous Paleontology, Miskatonic University
“You cannot reason a man out of a position he did not reach through reason.”

One reason to think of glass as a "super-cooled liquid is because there is no melting point. It just becomes less and less viscuous. Is this a property of all amorphous solids? Or do others, like wax, have a definite melting point?

I thought that my beer was liquid, but it was warm. So I put it into the freezer and forgot about it. It then became a solid. I waited until it was kind of slushy and ate/drank it like a slurpee. I burped a lot and even flatulated after it. Does that make it a solid, liquid or gas? :wink: