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At Oxford, a Battery That's Lasted 175 Years -- So Far
sarahnaomi writes There sits, in the Clarendon Laboratory at Oxford University, a bell that has been ringing, nonstop, for at least 175 years. It's powered by a single battery that was installed in 1840. Researchers would love to know what the battery is made of, but they are afraid that opening the bell would ruin an experiment to see how long it will last. The bell's clapper oscillates back and forth constantly and quickly, meaning the Oxford Electric Bell, as it's called, has rung roughly 10 billion times, according to the university. It's made of what's called a "dry pile," which is one of the first electric batteries. Dry piles were invented by a guy named Giuseppe Zamboni (no relation to the ice resurfacing company) in the early 1800s. They use alternating discs of silver, zinc, sulfur, and other materials to generate low currents of electricity.
At the current estimated power draw, thats only (1 nanoampere) * 175 years = 0.00153401723 ampere hours. It's a long time: impressive durability, but not really amazing capacity. Laptop batteries are often ~1000 times that. I don't know the voltage here, so I can't do energy comparisons, just total amp hours.
Actually I have to correct myself. I assumed it was low voltage, like a single cell battery, and thus around 1-2 volts. That's not the case - the voltage is around 2,000 volts:
http://www.sharingtechnology.n...
That means my calculations were off by a factor of 1333. So if you divide the times I stated for AA and D batteries by 1,333 and you'll get a more accurate figure. So even a deep cell 12 V battery, which is around 120 watt-hours, could only run the bell for 9.5 years. Guess that makes it more impressive than I thought.
Or my calculations are still way off.
Better known as 318230.
Actually the janitor changes it once a week when he cleans the room.
Hehe.. maybe he is. The municipal power company in Reykjavik, Iceland built a Focault pendulum in their HQ as a showpiece. Local urban legend has it that after it was first installed the thing would stop swinging at seemingly random intervals which caused the artist and the physicist who designed it a lot of head scratching. No amount of calculations, physics theory and modelling could explain these mysterious disruptions in the predicted workings of the pendulum so finally they set up a camera to observe the thing. The footage showed the pendulum swinging away for hours and hours until suddenly a member of the cleaning staff walked into the frame, stopped, looked at the pendulum, reached out, stopped it with his hand and then walked out of the frame. Mystery solved... dunno if the story is true but it made me laugh.
From The Fucking Article
"You'd think it'd be annoying as hell for a bell to be going off, constantly, for 175 years—but the voltage left in the battery is so low that the human ear can't actually hear the ringing. Instead, the clapper oscillates back and forth between the bell constantly, which you can see happening in this video. At this point, the experiment is more of a curiosity than anything—Croft says that the battery pulls 1 nanoAmp each time it oscillates between the bell’s sides, which is an exceedingly low amount of energy."
1 nanoamp is so tiny that it may be being recharged from the environment somehow.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
I expect you are correct. Put the bell in a Faraday cage and see if it stops twitching. The question is, is the signal being switched, electrostatic, magnetic?
Space may be a wonderful insulator, but the flip side to that is that there's nothing to reflect back your own heat. Radiative cooling can happen very quickly. This is why a desert can go from 100F to near freezing in a matter of hours when the Earth rotates and the desert is radiating heat out into space.
There's a reason why a vacuum flask (aka thermos) is silvered--it reflects radiation. A vacuum flask is silvered on the _inside_ (including the vacuum-facing walls) as well as the outside, otherwise any contents warmer than ambient temperature would radiate their heat much faster through the flask walls.
1 nanosecond..., honestly, that's typically British. In the US that battery would have been trashed already. The Brits are way too much attached to these long lasting historical figures. And royalty is another example.
Well, there is a light bulb in Livermore, CA that's been burning for 114 years. That hasn't been continuous as there have been some power outages and it's been moved a few times but the Livermore fire department seems pretty attached to it.
I hate to tell you this, but most people who've worked support in manufacturing and office environments have similar stories. I spent close to two months getting paged by Northern Telecom in Bramalea, ON for a manufacturing system failure on the shop floor at 2-3 AM most days per week. It was only by deciding to hang out for an entire night watching the area that I found out it was being caused by a cleaning lady unplugging the network bridge to plug in her radio while cleaning the area.
So seeing as I have one of those stories myself, I find them a lot easier to believe than most of you kids do.
I do not fail; I succeed at finding out what does not work.
I remember someone making a video about having some fun with a few hundred 9v batteries in series resulting in ~2000 vDC.