In New Scientist for 7 July 2001,p.50, there is a dandy UK word I think is superior to usual US equivalent. The article is about the early days of home radio reception, and to my amazement is about using illuminating gas to power a radio!
Because the Brit, Insull, did his work in US, just about everybody here had electricity in home in the twenties. I remember the A, B, and C batteries. The A and C batteries were carbon-zinc dry cells, but most of the power was supplied by the B cells, which had to be a regular automobile battery, that could be charged from the house electric current.
So I was surprised to learn that in Britain a very large part of homes did not have electricity, and the illuminating gas companies fearing loss of customers, promoted the use of a device that produced power from illuminating gas by "the thermoelectric effect: the generation of electricity in a circuit made of wires of different metals in which the junctions between those metals are maintained at different temperatures."
But the name of the device that stored the power so generated, was new to me. Except for our UK members, how many can guess what it was called?
Nope. It's just that the Brits use a word that makes good sense. Surprisingly, though, they use our word more often than the one of theirs I found so well chosen. At least in many sites I looked at to check.
?did you bother to tell us the US equivalent? (I feel like i'm groping in the dark)
The title is "power source". I said that the principal power for home radios in twenties was a regular auto lead acid battery. This is what Brits have a different name for.
Another clue. The lead-acid battery is rechargeable. The Brit name indicates this.
Well. Dr. Bill, I've seen the term "accumulator" used in this regard; kinda goes along with the archaic term, "condenser" for capacitor.
Your gas-powered thermocouple reminds me of the gas-powered refrigerators of former times. Anybody remember them?
Dear Geoff: You win the hand-painted pot. Chamber that is. Accumulator is the word New Scientist used, but far more UK links used lead-acid battery. As for gas powered refrigerators, the refrigerator in medical lab I worked in while in the Philippines was a Servel, running I think on natural gas. They had tubing on rear just like conventional refrigerator. I thought they were just a different type of heat pump.It was very satisfactory despite high temperatures - much of the time in high eighties and nineties.. I guess that there just wasn't enough demand for them to compete in US, though I wonder if some mobile homes might not still have them. While in Manila, I used to see big bomber circling overhead for sole purpose of making ice for the officers' messes. That must have cost taxpayers a bundle.
Dear Geoff: I looked, and there are many places still selling propane gas powered refrigerators, domestic and RV.
Many of them apparently use electricity for temperature regulation. Some use kerosene.
Remember them? They still use them in rural Mexico.
The Amish in Pennsylvania use gas refrigerators both in their homes and to cool milk in bulk. While electric refrigerators are forbidden, they have no problem with a device that works by using a flame. (They also use gas ranges and heaters, with no electric ignition, timers or clocks.) Along with some orthodox jews, they adhere to the letter of the law while finding ways to adapt to the needs of modern life.
And the Amish still use hay-burner transportation. My wife had a lot of Pennsylvania Dutch in her, and went to a family re-union in PA. She saw a properous Amish patriarch, with an extremely well finished buggy, and a gorgeous mare pulling it. She remarked what a beautiful rig he had, and was dumbfounded that his face turned dark with suppressed fury. I had to explain it to her.
Perhaps you could explain it to the rest of us as well?
Bingley
I was just handing BobY a post. The Amish are US principal exponents of conspicuous underconsumption. They sternly reject display of wealth, so that the deacon with his beautiful buggy and horse felt painfully rebuked to have their beauty and high cost remarked on in front of his peers.
The Amish in Georgia don't seem to have a problem with electricity or electronics. When I paid for a meal at an Amish restaurant, they took Visa, used a standard electronic till and telephones ...
I mentioned the term "conspicuous underconsumption". I think it might surprise you to know that the Rockefellers in the twenties practiced it. I knew a Harvard instructor whose father was an AT&T vice-president, and summered in Bar Harbor, Maine, and knew the Rockefeller children. One summer the kids were beach combing, and Nelson Rockefeller discovered a wrecked dory, and was trying to figure out how much it would cost to fix it up. A nouveau riche kid, less well brought up, sneered:"Why don't you buy a new one?" Nelson Rockefeller turned on him and demanded, quite sincerely, "What do you think I am, a millionaire?" He simply had no idea that the was indeed many times over a millionaire.
You wrote about the condenser/capacitor. About twenty years ago an engineer I knew who was working on the power plant up near Lake Anna told me not to run my automobile air conditioner with my window down. He said that practice would ruin my condenser. First, is this the same condenser in your reference; and, second, would you please explain in a few simple words whether this is true.I don't think it is the same sort of condenser. The thing in a car's A/C does something (what exactly, I'd have to look up) to make the air cold. A capacitor (also called a condenser) stores electric charge. Basically it is two metal plates quite close together, with a voltage across them. It just sort of "holds on" to the electrons. Normally these are quite small. If you look at any circuit board, the little things that look like yellow Chiclets are capacitors. Anyway, a microphone which uses a capacitor to convert sound to electric signal is called - you guessed it - a condenser mic.
Dear WW: your engineer who advised you not to have windows down when using air conditioner, had to be talking about putting excess load on the air conditioner. But I have no idea what he meant by "condenser" in that situation. The air conditioner is a heat pump, and used to use dichlorodifluoromethane as heat transfer agent. I don't know what he meant by condenser in this situation. Heat turns the refrigerant into a vapor. Compressing the vapor heats it very hot. When the pressure is high enough, the very hot gas opens a valve, and it passes into a long tube boustropheded (how do you like that coinage) into a small area, where it loses heat to the environment, and then is compressed again. In that long cooling tube, the gas would begin to condense, but I never heard it called a condenser. I suppose that the extra load on motor alternator from excess stress on air conditioner might stress alternator's capacitor, but I never heard it mentioned. Damn people who give lousy explanation, including me.
Yes, your PC has lots of little capacitors.. but don't go looking at your moniter.. it has huge capacitors.. and i have inadvertently discharged a 40 volt capacitor.. (a lot bigger than a chicklet!).. and trust me, 40 volts is no fun.. monitor capacitors can be quite high voltage.. 200 to 1000 volts... not something you want to accidentally discharge.
and yes, mobile home still use gas powered refrigerators.
Dear of troy: it is not just the voltage rating of a capacitor that matters. More importantly, the area that is charged determines the amount of energy that can be stored. This is measured in "farads", eponymic for Faraday, I suppose. Some of the early experimentors used Leyden jars, which were coated on the inside with silver plating, I think. Several of them in series could give an extremely unpleasant surprise if discharged from one hand to the other. Interesingly, there are eels that can store up a charge powerful enough to cause careless wader in tropics to be stunned and drowned. The muscles act like a long string of Leyden jars, and store enough electrons to cause an appreciable current. I think I have read of it being possible to make a light bulb flash with their discharge. I'll try to see if I can find anything on Internet.
Benjamin Franklin used a Leyden jar to store energy for kitestring which attracted lightning discharge. He was lucky he didn't get killed. Another scientist in Europe who copied him did get killed.
Here are some uRLs:
Leyden jars ;
http://www.alaska.net/~natnkell/history.htmElectric eels
http://www.sciencenet.org.uk/database/Biology/0104/b00906d.htmlElectic eel:
http://www.sidwell.edu/us/science/21bio/fish/organ.htmlI used to have some very high current capacitors to make flashes with xenon tubes such as are used on aircraft flashing lights. If I remember right, they were rated a couple hundred farads. Discharge from one of those could kill. I used them to make flash for camera in early fifties.
Nope. A condenser has no moving parts. What would get ruined is the compressor.
To piggyback on what Bill explained, this is how an AC unit or regfrigerator works.
The cycle starts with a gas at room temperature. Simple physics here: any substance has a certain amount of energy in it, which can be measured as heat or temperature. A cubic foot of air at 75 F has a certain amount of heat in it. Now, if you compress that cubic foot of air to one tenth or one twentieth of that volume, all of the heat is still there. But it gets concentrated. Consequently the measured heat of the smaller volume of air goes up dramatically.
The gas we use in these machines becomes a liquid at a certain pressure. The liquid then goes through a series of cooling fins (look on the back of your refrigerator. Lots of long skinny tubes (which means a great ratio of surface area to volume. The hot liquid cools down to room temperature.
Then the cooled liquid goes into an expansion chamber, where it expands back to the original volume. But the heat that was there originally is gone. So the expanded volume is MUCH colder. The very cold gas is piped through another series of thin pipes where it sucks up the heat that is in and around the pipes. That's how the coils in your freezer and refrigerator get cold!
Then, the warmed-up gas goes back to the compressor where it is compressed again and condenses into a liquid in the condenser.
You have just pumped the heat from the refrigerator into the air behind it. That's why you have to make sure there is good air circulation behind your refrigerator and that those external pipes (coils) are free of dust. The heat has to be able to go somewhere.
One little caveat, TEd. When you compress gas, you do work on it, and that takes the form of heat.A simple demonstration of this is to take a bicycle pump, put your finger over the place where the compressed air comes out, and push the plunger in -like a porcupine making love- very cautiously. If you press the finger over the opening too tightly, and move the plunger too powerfully, you can get a painful blister.
I suppose that the engineer said that I would ruin my compressor--and I've simply mixed the words up over the years...Yes, those verbal tics do tend to accumulate over time, don't they?
Volta, Alessandro, Count (1745-1827), Italian physicist, known for his pioneering work in electricity. Volta was born in Como and educated in the public schools there. In 1774 he became professor of physics at the Royal School in Como, and in the following year he devised the electrophorus, an instrument that produced charges of static electricity. In 1776-77 he applied himself to chemistry, studying atmospheric electricity and devising experiments such as the ignition of gases by an electric spark in a closed vessel. In 1779 he became professor of physics at the University of Pavia, a chair he occupied for 25 years. By 1800 he had developed the so-called voltaic pile, a forerunner of the electric battery, which produced a steady stream of electricity (see Battery). In honor of his work in the field of electricity, Napoleon made him a count in 1801. The electrical unit known as the volt was named in his honor. See Also Electricity: History.
I remember reading somewhere that he had dissected some frogs legs, and hung the muscles in a way that they came in contact with metal, and twitched. The fundamental fact is that when any two different metals are suspended in water, a weak electric current is produced as one of them goes into solution. This is called electrolysis, and is the reason that aircraft rivets loosen slowly if rivet composition varies even a very small degree from that of skin. It is also the reason that touching a fork to a tooth filling may be disagreeable. Some combinations of metals produce enough current to be useful. Hence the Voltaic cell.
"Volta, Alessandro, Count," Microsoft(R) Encarta(R) 98 Encyclopedia. (c) 1993-1997 Microsoft Corporation. All rights reserved.
Interesting that essentially all terms for electrical units are eponymous: volt, ampere, ohm, watt, farad, henry and joule. I am aware of only one exception: mho, derived from ohm.
http://www.bartleby.com/61/charts/M0182500.html
Dear Keiva: I challenge you to find another "retronomic" scientific unit. I doubt that there are any.
Sorry to be so late, WW - I forgot where this thread was. (Senility, you know) Anyhow, TEd explained the heat pumping cycle of a refrigerator quite well, but nobody's mentioned that in earlier times electricity was thought to "condense" on a plate in a capacitor, leading to the misnomer, electric condenser.
As for running the car's A/C with the windows open, I don't think I've ever seen a compressor ruined by doing so, but it would be possible. Some recent A/C systems run the compressor constantly, and control the temprature through the use of a suction throttling valve, while others use a fixed orifice. The older systems with both a compressor clutch and an expansion valve seemed a bit more prone to failure. I've been out of automobile service for ten years, so I'm not really up to date on this stuff anymore. Now, if you want to know about chain saws or lawnmowers...
This brings up yet another question: Why do we refer to the refrigeration system of an automobile as "air conditioning?" A heater also "conditions" the air, as do the emissions of a passenger who hasn't showered in some time, etc.
In reply to:
I remember reading somewhere that he had dissected some frogs legs, and hung the muscles in a way that they came in contact with metal, and twitched.
And reading accounts of his experiments was one of Mary Shelley's inspirations for Frankenstein.
Bingley
Bill:
There is heat input, but nowhere near enough to burn you. Yes the gas heats up, but for exactly the reason I stated. More molecules in a smaller volume.
Ted
I remember reading somewhere that he [Volta] had dissected some frogs legs, and hung the muscles in a way that they came in contact with metal, and twitched.
I always thought that was a Mr. (or M.) Galvan, namesake of words like "galvanize" who did the twitchy frog experiments, but I can't find anything online about it. Anyone else know more?
Dear Flatlander: I goofed. You are correct. Another of my senile moments.
Dear TEd: I kid you not. If you press a fingertip over air outlet of a bicycle pump firmly, depress the plunger forcefully, and then let up finger over air outlet just enough to let a small amount escape under pressure, and you can indeed get a burn and blister, though you may have to depress plunger several times. I have experienced this. Remember the mechanical equivalent of heat. Count Rumford discovered that if a drill for boring cannons got dull, so that no more metal was removed, heat continued to be produced as long asd you kept turning the drill, because the work was being converted to heat.He could keep water boiling away as long as the drill was turning while forced against the metal of the cannon being made.
The same effect takes place in an refrigerator compressor. But when you cool the compressed gas to environment temperature, and then let it expand in the food compartment, it can take up heat. But in a hot environment, the compressor has to work harder. I think this is what the engineer told Wordwomd.
Interesting that essentially all terms for electrical units are eponymousIt has been my experience that almost all of the SI units are eponymous. The only ones that aren't seem to be metre, kilogram, candela, mole, and second. See
http://physics.nist.gov/cuu/Units/units.html
Dear Bean: I had a patient named Candela, and she was not very bright. But not eponymic material.
always thought that was a Mr. (or M.) Galvan
Luigi Galvani. His wife divorced him, charging that electricity had become his mistress, and he had become revolting, without a scintilla of affection, since he was given to rubbing his rod in cat fur in a futile attempt to build a perpetual motion monorail - OOps - I'm stepping on someone else's lines!