h a l f b a k e r yMake mine a double.
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Made up of two Galileo thermometers, the left liquid-filled glass tube has 12 smaller bulbs, for the twelve hours. The right glass tube also has twelve, for 5-minute intervals. The temperature in the tubes is varied according to time, and each bulb inside has a time-tag dangling from it, instead of a
temperature tag.
There would be a bit of a confusion in the minutes tube during the hour-changeover, due to the tube taking a few minutes to cool, as well as twice a day for the hours tube, which would be rather interesting to watch.
A great conversation piece, as well as something nice to look at.
Galileo Thermometers
http://science.hows...com/question663.htm Very nice to look at. [DesertFox, Mar 04 2006]
[link]
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So, it takes a regular clock/timer to control a thermostat, which will control the HVAC handler, which will affect the temperature displayed in the Galileo columns, by which you can sorta tell the time that the regular clock registered some time ago? |
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It may be pretty, but it also seems rather redundant within its own operating system. |
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A friend recently picked up a broken sundial from the kerbside hard rubbish. I asked if he intended to stick a new pointer on it and get it working. Because his garden is too shady, we came up with a scheme to put it on the roof with a webcam giving a live feed, so you could kind of roughly work out what time it was just by looking at your computer monitor. + |
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/The temperature in the tubes is varied according to time/ |
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How? The idea might roll if it had a hub. |
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A hub? I don't understand what you are trying to say. |
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Let me try to explain, for those who dont understand. A Galileo thermometer (for those who don't know) is a glass tube filled with a liquid and small glass bulbs with weights of varying density. As the temperature goes up, the weigths expand ever so slightly, enough so that some will rise. |
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This clock displays time by altering temperature. Assume that the base temperature is at 100 F. At 12:00, no temperature change is needed. But as every hour passes, the tube heats up 2 F, causing a new glass bulb to rise to the top due to thermal expansion. Same thing with the minutes. |
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Pedantry: As the temperature goes up, the floaters go down. The supporting liquid becomes less dense, and is no longer able to support the heavier bulbs labelled with the lower temperatures. |
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The idea as a whole is whimsical and obscure, but not impractical. I like it. + |
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Actually [bb], it's the other way around. At higher temperatures, more float. Think lava-lamps. They work the same way :) |
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Well, the one I have works the way I described. I just went to double check, and find that the topmost bulb in the cylinder is tagged with 82 degrees. |
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I did buy the thing at Bass Pro Shop, on sale, so it could be some twisted imitation of a Galileo thermometer. It's new, so I have been watching it a lot and think I have it figured out pretty well. |
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The link is to an article that is very poorly written, and a bit confused, yet it is copied elsewhere. It isn't right to say that "The bubble that sinks the most indicates the approximate current temperature." Still, I read it to say that the balls will sink as the density of the supporting liquid decreases with increasing temperature. And the picture shows a 76 degree bulb near the top of the stack. |
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Lava lamps have nothing to do with it. Lava lamps are heated from the bottom (which generates a temperature inversion), and feature a floating liquid (the "lava") that is heated so it expands and rises into a cooler region where it cools and contracts so it sinks. A Galileo thermometer is heated from outside, and can have higher temperature water above lower temperature water. The supporting liquid expands and contracts, affecting its density, while the balls/bulbs/spheres are of a much more constant volume and density. |
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It is possible to make a Mylar ballon filled with helium into a sort-of Galileo thermometer. Get a new mylar balloon, filled tightly (so the volume remains constant) and ballast it with modelling clay until it floats on the thermoclines of the air within a closed room. It makes a nice house pet for winter days. |
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[baconbrain], you bring up a good point about the lava lamps, and the confusion may partly be due to my initial annotation above. [DesertFox] never actually stated anywhere in his idea exactly where his timed heat source was going to be located. When I first read the idea, I assumed he was going to heat the entire room environment on a timed cycle because that's the way normal Galileo Thermometers are influenced to exhibit a temperature. As you know, they are entirely cordless. |
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Even though [DesertFox] failed to specify the method of heat change in the original design statement or subsequent annotation, I now think he really meant that the heat source would be a thermostatically controlled element of some kind in the base of the glass tube, thereby establishing his comparison to a traditional lava lamp. |
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I'd still like this idea a whole lot better if [DF] had figured out a way to depict time that didn't require the use of a standard electric or mechanical timer to control his thermostatic heating element. |
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He could use a heating element which is switched on and off by the movement of the no. 12 bulb. The rate of heat input would be such that it takes about 12 hours to fully heat the water/liquid. Of course, the temperature rise would be non-linear. |
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Jurist: Well, there isn't any practical way to do that. Temperature fluctuates from day to day, and basing time solely off of temperature would seriously mess it up. |
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Oh, and heat lamps at the top, bottom, and back to maintain an even temperature. |
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Oh, and I realized I put it in "Product: Clock". Moved to "Product: Clock: Display" as originally intended. |
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