6 ms·

The unsolved secret of David Jones' perpetual motion machine [video]

61 points by rumcajz 9y ago

nerdponx 9y ago
So is there only one in existence? I take it his family will not allow anyone to dismantle the contraption.
- larrydag 9y ago
  Supposedly this one was made by David Jones in 1999 in a Vienna museum. https://www.youtube.com/watch?v=2dpmP_H1LBM https://www.youtube.com/watch?v=2dpmP_H1LBM
  - Too 9y ago
    Heat sinks indicate sterling engine? The one from the first one is probably also sterling although not as obvious.
    - larrydag 9y ago
      That's what I thought. Some sort of sterling engine. Yet sterling engines need a heat source and sink. Perhaps the fireplace is a proper heatsink?
- brennebeck 9y ago
  He actually made four, it seems. Sibling comment shows one but I haven’t seen the others yet.
larrydag 9y ago
Apparently its known to be fake by David Jones. He did reveal how it was made but the recipient is still keeping it secret. http://www.dailymail.co.uk/sciencetech/article-4762778/How-riddle-bike-wheel-finally-solved.html http://www.dailymail.co.uk/sciencetech/article-4762778/How-r...
jaclaz 9y ago
As a side-side question, is it just me or "unsolved secret" doesn't sound "right"? I mean, "unsolved problem" or "unsolved mistery" or "unrevealed secret", but "unsolved secret"?
- pvinis 9y ago
  Maybe "unknown solution" could work too, since it was an unsolved mystery, then someone solved it but didn't share the solution, so it's a secret to anyone else.
- Semiapies 9y ago
  "Unknown secret" or "hidden secret", maybe.
- gerdesj 9y ago
  "Unsolved {riddle|puzzle|mystery}" are the usual forms for a headline of this type in the UK. Part of the Beeb may have briefly lost the rule book.
alphabetter 9y ago
I missed David Jones' work when he was alive. Does anyone know of online resources about his inventions and writing? His books are out of print and hard to get hold off.
- hazeii 9y ago
  Nature and New Scientist online archives? (sub. required).
- dcminter 9y ago
  They're available on AbeBooks last time I checked. Buy "The Inventions of Daedalus" and if you like it also "The Further Inventions..." which are both fantastic. Alternatively you could read through his columns in back issues of New Scientist and Nature at your local library but won't get the additional commentary and goofy drawings. Finally, there's a documentary on his perpetual motion machines (possibly mentioned, haven't rtfa yet) which is more about the man than the machines. I had to write to its creator to get a copy though!
tawm 9y ago
Have they tried holding a geiger counter up to it?
shad0wca7 9y ago
Could it be something simple like a combination of measures designed to allow it to rotate for an extremely long time: - Vacuum enclosure (remove air resistance) - Perfectly balanced wheel (reduce bearing wear) - Excellent quality bearing / lubrication - Small electric motor & battery to provide enough force to allow for continuity once started externally
cabaalis 9y ago
I'm no expert, but every criticism I've ever seen of people's attempts at perpetual motion always seem to involve the fact that some part will wear out eventually. Such as "magnets will lose their pull over time" or "friction will eventually wear down this gear." I don't think those are valid criticisms of the machines. They are perpetual motion machines, not perpetual no-maintenance machines.
- maxerickson 9y ago
  So build one you can maintain without stopping it.
- QAPereo 9y ago
  The biggest objection is that any work results in dissipation, and any machine which seems to violate this is quietly cheating with some input of energy. Aka Thermodynamics Edit: what possible objection could you have to this?
- pvg 9y ago
  I can't think of any serious criticism of a perpetual motion machine that is based on that. What are some examples you've run across?
  - cabaalis 9y ago
    Well then you seem to agree with me? I'm quoting experience casually reading various articles in my lifetime regarding the machines. Again, I am not a scholar in this field.
    - pvg 9y ago
      How am I agreeing with you? I'm asking you where you've seen that kind of critique. It's not one that would be used in a middle school physics class or article aimed at the general public.
- craigsmansion 9y ago
  > every criticism I've ever seen of people's attempts at perpetual motion always seem to involve the fact that some part will wear out eventually. Every informed criticism of perpetual motion machines starts and ends with the second law of thermodynamics. Any experts will usually leave it at that, because people who want to believe in a perpetual motion machine, are going to believe in a perpetual motion machine and any deriving discussion is usually not that interesting.
Zenst 9y ago
Given the age of this creation,the era of crystal radio[1] as a power source would be my first leap-to conclusion, whilst not enough to get it spinning from a standstill, enough to maintain motion once at speed from an initial hand-spin. How could you test this - place in a faraday cage. If that kept it running then my next thought would be some form of dry-pile battery[2], which is equally old enough technology wise and also proven to last many decades [3]. But certainly a fun puzzle to ponder. [1] https://en.wikipedia.org/wiki/Crystal_radio https://en.wikipedia.org/wiki/Crystal_radio [2] https://en.wikipedia.org/wiki/Zamboni_pile https://en.wikipedia.org/wiki/Zamboni_pile [aka dr-pilebattery] [3] https://en.wikipedia.org/wiki/Oxford_Electric_Bell https://en.wikipedia.org/wiki/Oxford_Electric_Bell [example of dry-pile battery operating for decades]
- userbinator 9y ago
  My first thought was also a long-lasting battery and an electrostatic motor similar to those used in that bell. That along with the large moment of inertia of the wheel and very good (possibly magnetic suspension?) bearings, makes it possible for it to continue rotating for a very long time. Also, for a second looking at the title, I thought it was going to be this guy: https://en.wikipedia.org/wiki/David_L._Jones_(video_blogger) https://en.wikipedia.org/wiki/David_L._Jones_(video_blogger)
danmaz74 9y ago
If it's not possible to access the machine and experiment on it, how can we possibly know if somebody actually explained the trick correctly?
Animats 9y ago
When he first built that and wrote it up in his Daedalus column, I sent in my guess as to how it works. He replied, and said that wasn't it. Some students stole that wheel once, it continued to run, and they couldn't future it out. They gave it back after three weeks, embarrassed. He built four of those wheels. Here's another one.[1] I'm really impressed that they are running long after his death. [1] https://www.youtube.com/watch?v=2dpmP_H1LBM https://www.youtube.com/watch?v=2dpmP_H1LBM
- mhb 9y ago
  What was your guess?
asmithmd1 9y ago
My guess is it powered by changes in temperature and atmospheric pressure like Cox's clock: https://en.wikipedia.org/wiki/Cox%27s_timepiece https://en.wikipedia.org/wiki/Cox%27s_timepiece
ouid 9y ago
Unsolved and unverified are different.

61 points by rumcajz 9y ago

nerdponx 9y ago

So is there only one in existence? I take it his family will not allow anyone to dismantle the contraption.

larrydag 9y ago
Supposedly this one was made by David Jones in 1999 in a Vienna museum. https://www.youtube.com/watch?v=2dpmP_H1LBM https://www.youtube.com/watch?v=2dpmP_H1LBM
- Too 9y ago
  Heat sinks indicate sterling engine? The one from the first one is probably also sterling although not as obvious.
  - larrydag 9y ago
    That's what I thought. Some sort of sterling engine. Yet sterling engines need a heat source and sink. Perhaps the fireplace is a proper heatsink?
brennebeck 9y ago
He actually made four, it seems. Sibling comment shows one but I haven’t seen the others yet.

larrydag 9y ago

Apparently its known to be fake by David Jones. He did reveal how it was made but the recipient is still keeping it secret. http://www.dailymail.co.uk/sciencetech/article-4762778/How-riddle-bike-wheel-finally-solved.html http://www.dailymail.co.uk/sciencetech/article-4762778/How-r...

jaclaz 9y ago

As a side-side question, is it just me or "unsolved secret" doesn't sound "right"? I mean, "unsolved problem" or "unsolved mistery" or "unrevealed secret", but "unsolved secret"?

pvinis 9y ago
Maybe "unknown solution" could work too, since it was an unsolved mystery, then someone solved it but didn't share the solution, so it's a secret to anyone else.
Semiapies 9y ago
"Unknown secret" or "hidden secret", maybe.
gerdesj 9y ago
"Unsolved {riddle|puzzle|mystery}" are the usual forms for a headline of this type in the UK. Part of the Beeb may have briefly lost the rule book.

alphabetter 9y ago

I missed David Jones' work when he was alive. Does anyone know of online resources about his inventions and writing? His books are out of print and hard to get hold off.

hazeii 9y ago
Nature and New Scientist online archives? (sub. required).
dcminter 9y ago
They're available on AbeBooks last time I checked. Buy "The Inventions of Daedalus" and if you like it also "The Further Inventions..." which are both fantastic. Alternatively you could read through his columns in back issues of New Scientist and Nature at your local library but won't get the additional commentary and goofy drawings. Finally, there's a documentary on his perpetual motion machines (possibly mentioned, haven't rtfa yet) which is more about the man than the machines. I had to write to its creator to get a copy though!

tawm 9y ago

Have they tried holding a geiger counter up to it?

shad0wca7 9y ago

Could it be something simple like a combination of measures designed to allow it to rotate for an extremely long time: - Vacuum enclosure (remove air resistance) - Perfectly balanced wheel (reduce bearing wear) - Excellent quality bearing / lubrication - Small electric motor & battery to provide enough force to allow for continuity once started externally

cabaalis 9y ago

I'm no expert, but every criticism I've ever seen of people's attempts at perpetual motion always seem to involve the fact that some part will wear out eventually. Such as "magnets will lose their pull over time" or "friction will eventually wear down this gear." I don't think those are valid criticisms of the machines. They are perpetual motion machines, not perpetual no-maintenance machines.

maxerickson 9y ago
So build one you can maintain without stopping it.
QAPereo 9y ago
The biggest objection is that any work results in dissipation, and any machine which seems to violate this is quietly cheating with some input of energy. Aka Thermodynamics Edit: what possible objection could you have to this?
pvg 9y ago
I can't think of any serious criticism of a perpetual motion machine that is based on that. What are some examples you've run across?
- cabaalis 9y ago
  Well then you seem to agree with me? I'm quoting experience casually reading various articles in my lifetime regarding the machines. Again, I am not a scholar in this field.
  - pvg 9y ago
    How am I agreeing with you? I'm asking you where you've seen that kind of critique. It's not one that would be used in a middle school physics class or article aimed at the general public.
craigsmansion 9y ago
> every criticism I've ever seen of people's attempts at perpetual motion always seem to involve the fact that some part will wear out eventually. Every informed criticism of perpetual motion machines starts and ends with the second law of thermodynamics. Any experts will usually leave it at that, because people who want to believe in a perpetual motion machine, are going to believe in a perpetual motion machine and any deriving discussion is usually not that interesting.

Zenst 9y ago

Given the age of this creation,the era of crystal radio[1] as a power source would be my first leap-to conclusion, whilst not enough to get it spinning from a standstill, enough to maintain motion once at speed from an initial hand-spin. How could you test this - place in a faraday cage. If that kept it running then my next thought would be some form of dry-pile battery[2], which is equally old enough technology wise and also proven to last many decades [3]. But certainly a fun puzzle to ponder. [1] https://en.wikipedia.org/wiki/Crystal_radio https://en.wikipedia.org/wiki/Crystal_radio [2] https://en.wikipedia.org/wiki/Zamboni_pile https://en.wikipedia.org/wiki/Zamboni_pile [aka dr-pilebattery] [3] https://en.wikipedia.org/wiki/Oxford_Electric_Bell https://en.wikipedia.org/wiki/Oxford_Electric_Bell [example of dry-pile battery operating for decades]

userbinator 9y ago
My first thought was also a long-lasting battery and an electrostatic motor similar to those used in that bell. That along with the large moment of inertia of the wheel and very good (possibly magnetic suspension?) bearings, makes it possible for it to continue rotating for a very long time. Also, for a second looking at the title, I thought it was going to be this guy: https://en.wikipedia.org/wiki/David_L._Jones_(video_blogger) https://en.wikipedia.org/wiki/David_L._Jones_(video_blogger)

danmaz74 9y ago

If it's not possible to access the machine and experiment on it, how can we possibly know if somebody actually explained the trick correctly?

Animats 9y ago

When he first built that and wrote it up in his Daedalus column, I sent in my guess as to how it works. He replied, and said that wasn't it. Some students stole that wheel once, it continued to run, and they couldn't future it out. They gave it back after three weeks, embarrassed. He built four of those wheels. Here's another one.[1] I'm really impressed that they are running long after his death. [1] https://www.youtube.com/watch?v=2dpmP_H1LBM https://www.youtube.com/watch?v=2dpmP_H1LBM

mhb 9y ago
What was your guess?

asmithmd1 9y ago

My guess is it powered by changes in temperature and atmospheric pressure like Cox's clock: https://en.wikipedia.org/wiki/Cox%27s_timepiece https://en.wikipedia.org/wiki/Cox%27s_timepiece

ouid 9y ago

Unsolved and unverified are different.