Metrology crisis – the grand kilo loses mass

From the Wall Street Journal – By JEANNE WHALEN

In a vault beneath a 17th-century pavilion on the outskirts of Paris sits a platinum cylinder known as Le Grand K. Since 1889 it has been the international prototype for the kilogram, the standard against which all other kilos are measured.

This international prototype, made of platinum-iridium, is kept at the BIPM under conditions specified by the first General Conference on Weights and Measures (Conférence Générale des Poids et Mesures, CGPM in 1889. (Photo courtesy International Bureau of Weights and Measures)

But over the years, scientists have noticed a problem: Le Grand K has been losing weight. Weigh-ins at the International Bureau of Weights and Measures show that the bar has shed approximately 50 micrograms—roughly equal to a grain of sand.

The problem has vexed scientists who monitor the kilo the way tabloids track the waistlines of Valerie Bertinelli and Kirstie Alley. The stakes, however, are weightier.

“It’s a scandal that we’ve got this kilogram hanging around changing its mass and therefore changing the mass of everything else in the universe!” Bill Phillips, a Nobel Prize winning physicist, exclaimed at a scientific summit in London this week. No one knows for sure what went wrong with Le Grand K, but some theorize it lost weight from being cleaned.

KILO

Scientists are using a watt balance (pictured) to calculate Planck's constant, which will be used to define the kilo. Image: National Institute of Standards and Technology

 

Dr. Phillips and other mandarins of metrology were gathered at Britain’s Royal Society to debate an urgent question in the science of measurement—how to re-define the basic unit of mass, as well as other measurements such as the second, ampere, kelvin and mole.

The aim is to tie each to a widely accepted property of nature, rather than to a lump of metal or some other imprecise benchmark. The meter, for instance, was once measured as the distance between two notches on a metal bar. It is now defined as the distance light travels in a vacuum in 1/299,792,458 of a second.

The new definitions are “as big a change as the introduction of the metric system during the French Revolution,” says Terry Quinn, a dapper Briton who organized the seminar and once served as director of the International Bureau of Weights and Measures, which ensures world-wide uniformity of measurements. Frequent clashes about the best approach mean the temperature of debate has at times “risen quite high,” he added, without specifying by how much.

Full story at the Wall Street Journal

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140 thoughts on “Metrology crisis – the grand kilo loses mass

  1. The tweet really piqued by curiousity. This was an interesting aside from things and something I’ve never heard of before. More proof you’re never too old to learn. Thanks!

  2. The big reason the US never went on the metric system is that Jefferson found out everything would be administered by the French and he said NO WAY JOSE!

  3. Measuring mass at the microgram level is much more difficult than it would seem. Mass is often confused with weight, but they are not the same.

    The mass of an object is a quantitative measure of its inertia; its resistance to a change in its state of motion caused by a given force. Weight is not a constant property of matter, but depends on its location. In space, an object still has mass, but its weight is zero.

    Temperature, humidity, pressure, uncertainty, and drift in the weighing system all affect mass calibrations done in the microgram range. For example, the uncertainty alone in a 1 gram weight is .005 [mg, 2 sd].

    In determining a small mass in the microgram range, numerous measurements are taken. It’s not simple, like putting weights in a balance.

  4. Now which would be the preferred grammar: “Heisenberg may have farted here,” or “Heisenberg might have farted here”?

  5. “The problem has vexed scientists”………
    ===
    Beware the “vexed” scientist, ‘cus that is what they live for.

  6. ” The meter, for instance, was once measured as the distance between two notches on a metal bar. It is now defined as the distance light travels in a vacuum in 1/299,792,458 of a second. ”

    That should be of vast help in precision shed-building.

  7. Frequent clashes about the best approach mean the temperature of debate has at times “risen quite high,” he added, without specifying by how much.

    It’s worse than we thought …

  8. Blimey – that means the earth’s oceans are now 36 sq km bigger than they were. Hang on a minute: Dr T’s missing heat… could it be that, with the odd solar eclipse thrown in perhaps …?!

  9. The first question should be if NOAA was given the data to adjust……

    If you graph the weight since 1889, do you get a hockey stick??

  10. ‘u.k.(us) says:
    January 28, 2011 at 5:16 pm
    “The problem has vexed scientists”………
    ===
    Beware the “vexed” scientist, ‘cus that is what they live for.’

    Send more money.

  11. Not to be pedantic but if this is “the standard against which all other kilos are measured” how do they know it is losing mass?

  12. “The meter, for instance, was once measured as the distance between two notches on a metal bar. It is now defined as the distance light travels in a vacuum in 1/299,792,458 of a second.”

    Hmmm. No adjustment for a relationship between lightspeed and gravitational field strength eh? I wonder how long that’ll stand up.

  13. I remember when the K, actually gained weight.
    Were the laws of nature changing beneath our feet?
    Some higher intelligence changing the rules?
    Thankfully not. It turned out the cleaning method had changed. Air drying failed to remove metallic deposits breathed on it from a technicians filled teeth.The previous method of using a soft cloth had always removed them.
    And the laws of the universe steadied.

  14. [snip - "Electric universe" has nothing to do with this and is nothing but traffic trolling, take it elsewhere - Anthony]

  15. From the image:

    Scientists are using a watt balance (pictured) to calculate Planck’s constant, which will be used to define the kilo. Image: National Institute of Standards and Technology

    Let me be the first to say … Watt?

    .

  16. Terry Quinn may be dapper but he’s hyperbolic. The French Revolution standardized and rationalized a lot of measures. These changes are incremental, and a very tiny one at that. Nice, though; I’ll give ‘em that.
    ===============

  17. Phil’s Dad says:
    January 28, 2011 at 5:55 pm
    Not to be pedantic but if this is “the standard against which all other kilos are measured” how do they know it is losing mass?
    ======
    Or (gasp) maybe it’s gaining mass.
    It’s time to take a vote.
    We need a consensus!!!

  18. But in 16th century Scotland the people had to do with James V’s pronouncement;
    “Tak’ the meesure of a sma’ maun’s nose to his finger-tip. Tak’ the same from a reeg’lar maun, and a meikle maun. Combine all and divide by three. Yon is yi’r Yaird.”
    Simples!

  19. Is the premise that the fundamental behavior of nature/reality does not vary over time and space just a convenient assumption? Is it the ultimate null hypothesis?

    John

  20. Here is something for some poor slob of a PhD student to waste their life on: Assume neither energy or matter is created. Assume that the universe is expanding. The vacuum energy is known to exist and has mass equal to E=Mc^2. Since the total percentage of the volume of the universe occupied by the masic kilo is decreasing the amount of vacuum energy it contains is decreasing,. This is equalvalent to a decrease in its mass. You may now work on this for the next 10,000 years and still not come up with a good thesis to publish. But don’t say I didn’t warn you.

  21. I thought a kilogram was defined as the mass of a litre of water. A litre is 1/1,000 cubic metre and we know how to define a metre now (i.e. light travelling in 1/299,792,458 of a second), so what’s the problem?

  22. There is a radioactive isotope of Pt which is 0.014% abundant and is an alpha emitter. The half life is absurd… 6.5 x 10^11 years, but after nearly 200 years and with 1 kg of material, it is reasonable that 50 micrograms of helium would be lost from the sample from alpha emission. (The exponent value in the half-life equation is 0.999999999.)

    Alternatively, this sample of platinum could already have helium inside of it and it could be lost over 200 years through slow diffusion.

    Serves them right for picking something with a radioactive isotope.

  23. French also tried to make metric time and metric calendar… Fortunately it was so inconvenient that it did not last long.

  24. Steve in SC says:
    January 28, 2011 at 4:53 pm
    The big reason the US never went on the metric system is that Jefferson found out everything would be administered by the French and he said NO WAY JOSE!

    At least 80% of their electrical generation is nukes. Not to shabby.

  25. Chris Reeve says:
    January 28, 2011 at 6:35 pm
    There exists no enigma within the Electric Universe paradigm…
    It testifies to the growing scientific illiteracy that such nonsense can be uttered.

    REPLY: I agree, and I have removed that very long and nonsensical comment as it has no place here whatsoever. Mods, please tighten up to prevent such off-topic ridiculae. – Anthony

  26. I’m amazed what I learn from WUWT. Until a few days ago I did not know that metrology was the science of measurements, but I learned that from your post on the metrology of thermometers. That’s a lot to learn for a know it all.

  27. Smokey says: “In space, an object still has mass, but its weight is zero.”

    I like everything else you said, but I must quibble with this. Gravity doesn’t stop just because you are in space. In orbit the object would be “weightless” but that is because it is in freefall, not because gravity has stopped pulling on it. It would be just as “weightless” in an elevator that is in freefall.

    Michael says: “I thought a kilogram was defined as the mass of a litre of water. ”
    That was the original definition, but that has not been the official definition of a kilogram for a looooong time.

    DocattheAutopsy says: “There is a radioactive isotope of Pt …it is reasonable that 50 micrograms of helium would be lost”
    From your own numbers, we can look at the orders of magnitude: about 1 out of 10,000 atoms are radioactive, about 1 out of a billion radioactive atoms would have decayed, which would be on the order of 0.0001 micrograms of radioactive Pt have decayed. No way that would be a 50 microgram loss. .

  28. The big reason the US never went on the metric system.

    The US is tied firmly to the metric system. You guys have several verified kilograms and your weights are defined in terms of them. All your physicists, chemists etc use metric, because to do otherwise would be daft.

    The resistance of the US to a convenient and international system is nothing to be proud of. It’s like those people proud of being illiterate – because they’d never seed the point of book lernin.

    I thought a kilogram was defined as the mass of a litre of water.

    Both hydrogen and oxygen have commonly occurring isotopes. That means a litre of water in one place has a different mass from a litre of water in another. You could define is at water of 1-H and 16-O, but it is hard to make that with any degree of purity.

  29. Reply to Phil’s Dad (@5:55pm)

    From the second-last para of the WSJ article:
    “Several dozen copies of the original are stored at national laboratories around the globe. Once every 50 years or so, scientists carry the copies by hand to Sèvres, just outside Paris, in little boxes, to compare them to the original. At the most recent summit in 1989, they noticed that the kilos differed by an average of about 50 micrograms. This is often described as Le Grand K losing mass, though to be precise, it’s possible that the copies had gained mass.”

    Up to now, that is all you can do … compare a whole bunch of ‘copies’. (Some say there are 80 copies.)

    But Australia’s CSIRO has been co-operating in a long term international venture, the Avogadro Project, to redfine the standard of mass in terms of Avogadro’s number, using a series of precisely manufactured spheres of Silicon.

    The basic idea is to control the isotopic form of the Si during the crystal growing process (thanks to semi-conductor technology), then create a series of ‘near-perfect’ Si spheres of a precise diameter (93.6 mm) and shape (diameter controlled to “35 nanometres”). See one of several relevant CSIRO articles.

    Of the 14 spheres manufactured by CSIRO’s Australian Centre for Precision Optics (as at April 2008), 12 have ‘out-of-roundness’ varying from about 63 – 70 nanometres; the best two have no more than 35 nanometres ‘out-of-roundness’.

    Just think about that; that is equivalent to less than 5 mm ‘out-of-roundness’ on a sphere the size of the earth! (If only somebody would pay so much attention to averaging its temperature!)

  30. Correction to my previous post: “5 mm” should be “500 mm” (unless I’ve made another mistake!).

  31. Can the rules on discussing gravity and mass be clarified?

    Am I being prevented from discussing how another framework would explain the same observation? What is the problem? Do you want me to explain it in my own words?

    In the prior thread I participated in, I did not see a single complaint. Everybody seemed content to hear about it.

  32. I’m surprised those sneaky conniving metrologists didn’t just get together and figure out a way to hide the decline….

  33. We now know the speed of light in a vacuum exactly.

    Incidentally, we ARE indirectly on the metric system now.

    http://en.wikipedia.org/wiki/Inch

    “Effective July 1, 1959, the United States and countries of the British Commonwealth defined the length of the international yard to be exactly 0.9144 meters.[1] Consequently, the international inch is defined to be equal to exactly 25.4 millimeters. “

  34. Hmm, about 50 ppb over a long period. I would agree a cleaning operation sounds likely as the source of removal. Could there be a small evaporation rate, Pt sublimation or diffusion into the supporting material?
    So the tension between deposition and evaporation goes on. I presume they have to clean it, or it “gains” weight as surface layers accrete from the air, as tightly controlled as it may be. But if they clean it it loses material… sounds like a tough job.

  35. John Brookes says:
    January 28, 2011 at 8:11 pm

    I’m surprised those sneaky conniving metrologists didn’t just get together and figure out a way to hide the decline….

    You’re confusing metrologists with climatologists John

  36. Anthony, you should consider changing the title of this blog entry because its not certain that the grand kilo is losing “mass” .. it could be something else.

  37. The metre is now the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second (with or without a gravity field?). A second is no longer connected to the length of a day and its sub-divisions but is now the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom at rest at a temperature of 0 K.
    By 2015 the kilogram could be related to the Planck constant where the numerical value of the Planck constant will be fixed.
    (A side issue is that if THE Standard kilogram is by definition a kilogram then it cannot – by definition – be losing mass – everything else must be gaining!!!!)
    A long way from the days of Edward I when a Yard was set by the “Iron Ulna of our Lord the King”. All of this is no doubt a great advance and necessary but I have difficulty to relate to the new definitions. I cannot invoke any image of 9 192 631 770 periods of a radiation or the 299 792 458th part of a second and I feel that something is being lost……

  38. Once again, it’s the “saucer people”. After their tankers dump their snow load and before they pick up our sea water for their return trip home, the crews take a short R&R. They sneak in under cover of darkness and LICK that chunk of platinum with their sand-paper, cat-tongues. Gets ‘em high as a kite. The promise of a “platinum lick” is a big recruiting tool down at the saucer-crew union hall.

  39. @DocattheAutopsy says:
    January 28, 2011 at 7:06 pm

    “…it is reasonable that 50 micrograms of helium would be lost from the sample from alpha emission….”

    Ahh, that would be “cold diffusion” then.

    But seriously, you may have a point.

  40. Mooloo says:
    January 28, 2011 at 7:54 pm

    The resistance of the US to a convenient and international system is nothing to be proud of. It’s like those people proud of being illiterate – because they’d never seed the point of book lernin.

    Well, it’s always hard to trace something like that down to a single reason, but if your argument rests on calling your intended new partners a bunch of illiterate hicks, it’s not a *terrible* shock they didn’t flock to your side in the debate.

    If you were an ambassador, I’d bank on a war comin’.

  41. 55 micrograms of platinum is worth about 0.17 cents, which would be lost in the roundoff error nowdays, but prior to 1960 it would’ve been around 84 centimes (the French changed the franc in 1960 to be worth a hundred of the old francs, so an old centime is 0.0001 new francs). The detectives working this case should simply compare the value of platinum in French or Swiss francs over the years (this thief is extremely clever, so the money is probably going into a Swiss bank account) and look for unexplained bank deposits of that amount.

    Meanwhile it’s time to stick their kilogram in a vacuum chamber and deposit another 50 micrograms on it.

  42. fhsiv says:
    January 28, 2011 at 6:40 pm
    Is the force of gravity changing at that location?
    ________________________________

    Have the French lost some of their “Gravitas”?

  43. I cry Foul !!!!

    ktwop says:
    January 28, 2011 at 8:55 pm
    …..
    (A side issue is that if THE Standard kilogram is by definition a kilogram then it cannot – by definition – be losing mass – everything else must be gaining!!!!)
    ….

    I’ve been on this diet for years – and now all my efforts are in vain – weight increase and I didn’t even get to enjoy it!!!!!

  44. Why would they be cleaning it in the first place ? It appears to be stored under vacuum in multiple layers of Bell jars. How exactly does it get “dirty”?

  45. Smokey says: January 28, 2011 at 5:08 pm
    Measuring mass at the microgram level is much more difficult than it would seem. Mass is often confused with weight, but they are not the same.

    The problem was that they measured local gravity with the GRACE satellites.

  46. Michael says:
    January 28, 2011 at 7:05 pm

    I thought a kilogram was defined as the mass of a litre of water.

    A litre is the measurement of volume and so it’s mass is a variable dependent on temperature or pressure.

  47. You flippant commenters do not appreciate the gravity of the situation.

    The implications of this scandal are massive!

    How long must we weight before someone decides to take action?

    ….

    I’ll get me coat! ;-)

  48. Its great to read the comments on WUWT there is more humor here than anywhere else on the web. I can’t stop laughing at some of the comments, even though they carry serious scientific comment along with them. Well done !!

  49. “Several dozen copies of the original are stored at national laboratories around the globe. Once every 50 years or so, scientists carry the copies by hand to Sèvres, just outside Paris, in little boxes, to compare them to the original. At the most recent summit in 1989, they noticed that the kilos differed by an average of about 50 micrograms. This is often described as Le Grand K losing mass, though to be precise, it’s possible that the copies had gained mass.”

    It is curious that it differed to all copies and the *average* was 50 µgrams, not that it was off by 50 µgrams to all of the copies. Stored at national labs huh?

  50. It’s just that if I wanted to store a block of matter and be absolutely sure that nothing under control could possibly affect it’s mass I’m positive I would not choose a high-energy research national laboratory to store it during the fifty years of the most intense nuclear experiments. What were they thinking?

  51. It’s worse than we thought! Le Grand K
    Is steadily wasting away.
    My mass, then, gets greater?
    Let’s massage the data,
    And hide the incline. That’s the way.

  52. When you measure something, allways measure three times. Because nothing is easier than fooling yourself during the process. My bet is on the measuring equipment being a bit “out”.
    Question: How do they perform a calibration of the measuring device? Now, thats a good one, dont you think?

    On the funny side I collected the following possibilities from the commenters here;

    -It is converted to Dark Matter. ( It doesn’t matter, does it?)
    -Heisenberg farted somewhere in the room. (You cannot see it, but it is there, somewhere)
    -The GRACE satelite passed over it, and its pulling force lightened it.
    -NOAA and GISS adjusted and homogenized the statistical results.
    -Cold fusion converted some mass to gravitons and hydrinos.

    And perhaps;
    -It was measured in lbs, and converted to Kg using a super duper computer.
    -A French Aristocrat lost some perfumed powder on it from his whig.This contained
    a radioactive powder called Curiositum, which is now decayded into mediocrecum.

  53. This reminds me of the old story about a Mechanical Engineer, a Civil Engineer and a Physicist arguing about in a bar whose work was most accurate. The Mechanical Engineer was used to measuring to the nearest micron. The Physicist airily pointed out that when he measured distance it was how far light travelled in an infinitesimal fraction of a second. The Civil Engineer took a swig of his beer and pointed out that when he was building something he didn’t allow for error at all. He always checked through his theodolite and gave a thumbs up when it was absolutely “spot on”!

    (Needless to say, I’m a Civil Engineer.)

  54. Infamous British joke.

    English salesman to mystified French buyer: “Of course we quote the weights in pounds & ounces. Avoirdupois is your lingo, isn’t it?”.

    The word avoirdupois is from Old French aveir de peis (later avoir de pois), literally “goods of weight”.

    http://en.wikipedia.org/wiki/Avoirdupois

  55. Americans
    measure their blood pressure metric
    make their spectacles metric
    use metric units like Volts and
    yes, a WATT is a metric unit and depends on the kilogram.

  56. if your argument rests on calling your intended new partners …

    If the US were persuadable by reason, they would be metric by now. Like the rest of the world.

  57. “Le Grand K has been losing weight. Weigh-ins at the International Bureau of Weights and Measures show that the bar has shed approximately 50 micrograms—roughly equal to a grain of sand.”

    Just to state the obvious: How could the Big K be losing micrograms, if the Big K defines what a microgram is?

  58. One comment from a metrologist ‘This has changed the mass of everything in the universe’. No it has not. It has changed our figures not anything else.

  59. The answer is simple. The rotation of the Earth is slowing, so the mass has stayed the same while the weight has lessened. This is almost certainly due to the effects of AGW.

  60. When it comes to metric vs imperial I like to dig this little page out: Making An English Foot and Chasing the Greek foot.

    Whilst you could argue about cups and teaspoons and so on until you’re blue in the face, the basic measurements of length in customary units are rather less arbitrary than you’d think. I have a suspicion that the basic weights aren’t arbitrary either but I’m not in a position to research it, being nowhere near as smart as the man behind that there blog. :)

  61. Okay. My theory is that the cleaning crew is taking home the cleaning rags in their lunch buckets and saving them until they have enough platinum to take a nice long holiday. Brilliant of them, though it could take a while, eh?

  62. Archonix says:
    January 29, 2011 at 2:45 am

    When it comes to metric vs imperial I like to dig this little page out: Making An English Foot and Chasing the Greek foot.

    Whilst you could argue about cups and teaspoons and so on until you’re blue in the face, the basic measurements of length in customary units are rather less arbitrary than you’d think. I have a suspicion that the basic weights aren’t arbitrary either but I’m not in a position to research it, being nowhere near as smart as the man behind that there blog. :)
    —————————————————————————-
    Yep, the trouble with metric measures is that they only roughly correspond with human experience. Even though Australia changed to metric decades ago, people still report height as 5’9″ or 6’2″ rather than the metric equivalent. Part of the problem may be in the scaling. An inch (around the length of a thumb joint) is much more useful in everyday life than a cm. Same goes for a foot, which we have to deal with much more often than a metre. Maybe metrics should incorporate a new measure or measures which recognise these realities.

    Still, it is pleasing to hear that there are scientists who, instead of trying to ‘hide the decline’, are actively and publicly looking for the reasons for it.

  63. There are two obvious options here, unless I’m missing something.

    1: They know the electrochemical properties of platinum, so they could just deposit another 50 micrograms onto it; and

    2: Rename it the Standard 0.999 999 950 Kilogram.

  64. Slacko,

    “Hmmm. No adjustment for a relationship between lightspeed and gravitational field strength eh? I wonder how long that’ll stand up.”

    No adjustment necessary. The speed of light in a vacuum is constant everywhere to all observers no matter how they are travelling or what gravitational fields are involved. Gravity does not slow down the speed of light – it lengthens the wavelength and reduces the frequency by the same amount. The speed, which is a product of the two, remains the same.

  65. Mooloo says:
    January 28, 2011 at 7:54 pm

    The resistance of the US to a convenient and international system is nothing to be proud of.
    =================

    The first point is that all scientists use the metric system – yes even US scientists. I would not argue that the metric system is perfect for science. However, there is nothing convenient about it for the ordinary user, and I applaud the Americans for maintaining their own (British derived) system. We in the UK are sick of overzealous jobsworthies coming down on market traders for daring to sell apples by the pound. To be perfectly honest, it is much more intuitive to gauge lenght in feet, inches and yards rather than the ubiquitous millimetres. When I go into a store to by a sheet of wood, I don’t want to be told it is 2700 millimetre long, and 1257 millimetres long. I then have to do a mental calculation to convert it to something meaningful.

    All British measurements are what they are because they served a function. The yard was a measure of textile, the inch is the distance from the joint of the thumb to its tip and the stone was a convenient weight for fishmongers to use. These measurements are all part of a rich heritage of anglo saxon culture, and to stamp them out under the boot of uniforminisms is a great shame, and is something to be deplored, not celebrated.

    Not even American made documentaries are safe. When I watch an episode of Mythbusters, and they are driving a car at a certain speed, which I know is in miles per hour because it’s a US vehicle, I get really ticked off when the narrator tells me what the speed is in kilometers per hour. It’s like the US documentary is somehow ‘unclean’ and not fit for British consumption until converted to metric. Appalling!

  66. It seems somewhat superflous to add my two cents worth, but metric measurement is not as simple as some here have implied. In the world of textile manufacturing, the Europeans made very clever and beautifully made flat-bed and rotary knitting machines and looms for generations, but almost every individual manufacturer developed their own standard for screw and bolt threads. They all used metric units of measure, but that’s as far as standardisation went and the problems that arise when such technology is sold across the world is difficult to quantify. The world never hears about it, of course, as engineers the world over don’t shout about problems, they just quietly go about their work successfully sorting such problems out.

  67. Since the international insults are starting to fly, I feel free to offer the following: during the build-up to Gulf War I, when President Bush was trying to build an international coalition to fight Saddam in Kuwait and the French were resisting, my uncle (a military man) opined, “Going to war without the French is like going duck hunting without an accordion.” Absent Napoleon, the French have always been a little “light.” :-)

  68. Archonix, Johanna —

    I can’t lay my hands on the book, and it doesn’t seem to be on line (or, at least, not easily found), but when Thomas Jefferson made his proposal for uniformity in weights and measures he discussed the matter. He thought that the fundamental unit was the gallon, and that the unifying principle was weight — a “wine gallon” of wine weighed the same as a “corn gallon” of grain, thus “…making it indifferent whether the goods were sold by volume or weight”. It might be worth further study.

    Regards,
    Ric

  69. “pcs77 says:
    January 28, 2011 at 5:20 pm

    I wish I lost weight every time I cleaned myself!”

    Of course you won’t lose weight cleaning yourself, you must have someone else clean you!! I personally have lost 3 lbs (er, light kilograms) by non-self cleaning.

  70. It will make a good museum piece. Retired metrology fans can look at it with a tear in their eye remembering all the good times and measurements but wondering how the standard could have failed.
    It was great for its time but maybe the science outgrew the standard before cleaning standards were developed by the French.
    Now it is time to move on, I’m thinking carbon or anything to do away with conversion tables.

  71. I congratulate WUWT on having a few recent posts on meterology. For too long this has been the dowdy, boring, second-cousin-twice-removed of the sexy siren ‘climate science’.

    Some of the extraordinary leaps of ‘logic’ that have been made by AGW alarmists, especially in modelling, are based in ignorance or misunderstanding of meterology. Whether you are measuring coastlines, temperatures, rainfall or ice levels – believe nothing you because you are told, or, it ain’t necessarily so (UK and US versions respectively).

    Anthony’s exercise about the integrity of temperature measuring stations should surely have sent alarm bells ringing. That it goes to the core of ‘climate science’ was considered less important than fancy computer models and Al Gore’s evangelism.

    Discussions about measurement are a vital contribution to all of the sciences.

  72. It’s great fun to get a scientist all worked up by suggesting they work in English units (or what I consider “normal” units). Outside of the science community, haggling over 50 micrograms of mass is a total waste of time. The metric system, and all the associated standards defined to however many decimal places, are probably a big help in defining laws of physics or whatever. In the grand scheme of building things to make the world a happy, safer, better place, it makes no difference at all.

    I agree with the previous poster that English units are based on useful, intuitive standards. I’ve measured distances with my thumb in construction work, and I’ve measured rope and chain in yards by stretching it from my nose to my fingers. Many things in life are sized to whole English units, as whole units are easier to remember. When building in metric units, you either change the overall size of object to measure in whole units, or you don’t round off. Either way, it just isn’t intuitive.

    As an engineer, there aren’t many things I can’t design and build using inches and two decimal places. If I need high precision for machined parts, I’ll use three decimal places, or perhaps four decimal places in rare circumstances. I have yet to see where English units have been a limiting factor on building anything. Cars, boats, buildings, dams, aircraft, spacecraft; they seem to do just fine using inches.

    If you want to see problems, then force everyone to stop using intuitive, traditional units and move them to a system that has little reference to everyday life. When I was in elementary school in the ’70s they tried to indoctrinate us with the metric system, and replaced our classroom yardsticks with meter sticks. All I remember about them was that they were around 39 inches long…. The only remnant I see from the big ’70s metric push are two-liter soda bottles.

    For those who grew up thinking in metric, great. But I don’t see a compelling need to break a system that works just fine, just to make someone else feel better about themselves. Those who have issues with the US using English units need to take it up with our UK friends. They foisted the system on us long ago.

  73. 1. Alert Bernanke. Inflation is a force of nature.

    2. There’s a really clever cartoon in there somewhere on the input, output and feedback mechanisms on the temperature of debate ala energy models. I’m not a cartoonist though.

  74. I agree with the sentiment in favor of traditional units for everyday use.

    But, as an engineer in the aerospace industry, I have found the metric system to be of wonderful utility through the fact that all the basic units are dimensionally compatible, with no bizarre conversion coefficients. Doing thermodynamics of combustion, for example, is much easier if the heat of combustion is expressed in joules/kilogram instead of BTUs/pound…and I want to eventually get to watts of electric power. The true unit of mass in the English system is the “slug,” a very unintuitive unit. Alternatively, there is a unit of force called the “poundal.” It all depends on whether you want to work in pounds-mass or pounds-force. When you get to the units of viscosity, well…it is almost hilarious.

    As a result, I am “bi-metrical;” I can compute in either system. And, by the way, it is perfectly possible to produce to metric dimensions on English-system equipment. All that is required is for the dimensional conversion to be accurate to a compatible level of tolerance. We built missiles that way, and our versions flew better than the French versions (though we got no credit…using the same drawings).

  75. johanna,

    I noticed that same thing about Australians and their height about 25 years ago. I was a student intern at Argonne laboratory and there was a gent from NSW there. During an evening of beer consumption and lengthy coaching on the proper way to pronounce the word ‘bastard’, the issue came up of Americans’ reluctance to embrace the metric system. After putting up with a fair amount of good natured ribbing I ask Ken how tall he was. His reply? “5 foot 11, you bastard.”

  76. I wonder if the mass was not lost but the gravitational constant of the planet has dropped it would not be not measurable by tests but it caused everything to lose weight by a grain of sand.

  77. I have yet to meet an American who can tell me
    1) how many feet to a mile
    2) how many square-feet to an acre
    3) what a pound is, and what is measured by it
    4) how many Watts in a horsepower
    5) the unit one measures blood pressure in
    All very simple if you know metric.
    But when it is important, even Americans go decimal: A $ has 100 cents, not 64.

  78. Since the masses are only compared every 50 years (from OzWizard’s comment) has the technology changed in how they do this measurement. It would not be impossible to me that the difference in mass is due to knowing the relative values better than 50 years ago.

    If I remember correctly they do take many measurements and use the average value to get a more precise measurement. How precise are the measurements? 50 micrograms seems like a really big error. My 100 gram standard weight is rated to 10 micrograms.

  79. Earle Williams says:
    January 29, 2011 at 9:47 am

    johanna,

    I noticed that same thing about Australians and their height about 25 years ago. I was a student intern at Argonne laboratory and there was a gent from NSW there. During an evening of beer consumption and lengthy coaching on the proper way to pronounce the word ‘bastard’, the issue came up of Americans’ reluctance to embrace the metric system. After putting up with a fair amount of good natured ribbing I ask Ken how tall he was. His reply? “5 foot 11, you bastard.”
    —————————————————————–

    Earle, if he called you that, you were undoubtedly classified as a friend, or mate. The term ‘bastard’ in Australia is often affectionate, and no-one connects it to its original meaning of not knowing, or being acknowledged by, one’s father any more.

    Interesting to read posts from people who are ‘bi-lingual’ in metric and other measures. That is how it is in Australia, despite decades of metrics. As I suggested earlier, perhaps we need a metric equivalent to the inch and foot.

    Measurement nerds, arise! The steamrolling of your knowledge in discussions about weather and climate has gone on for too long.

  80. Stupid newsies! Don’t they check to see if they have run this story before? This is old, old news. News stories about an inconstant kilogram have appeared off and on since 1990. They pop up often enough that the BIPM (the organization that keeps the international kilogram prototype in a basement of a castle outside Paris) have a FAQ entry on it: http://www.bipm.org/en/scientific/mass/faqs2_mass.html.

    As others have noted, there are a number of competing approaches to eliminate the need for that prototype. It would be extremely nice to do so; the kilogram is the last of the basic units whose definition still relies on a prototype. However, the replacement will have to (a) be as accurate as the prototype-based approach, (b) based on extremely solid science, (c) verifiable, and (d) replicable. So far, no joy, but there has been a lot of progress as of late.

  81. Mass – The rest mass of an electron,
    Distance – The diameter of a helium nucleus,
    Time – The time it take a photon to cross a helium nucleus,

    etc

  82. As a civil engineer, I am always concerned about that thing called praticality and potential for error, as well as usefulness.

    Our use of stations (100 feet) and a decimal foot for measurement of length was wonderfully practical. Say 20+75.27 for 275.27 feet, or 2300+27.75 for 2327.75 feet. People are prone to make errors in transposition with long strings of characters. Misplacing the decimal point left or right one place with long strings of numerical characters became too common when digital calculators became common, making a result off by a factor of 10.

    With the metric system, the units are either too large or too small to be of practical use for civil engineering, in my humble opinion. I have used both, as a civil engineer.

    As I majored in physics back in the late 1950s (2 semesters first as a pre-engineering student, 1953-1954), I am familiar with the three systems, centimeter -gram-second (cgs), meter-kilogram-second (MKS) and foot-slug-second, used then.

    The right tool for the job at hand works well indeed.

    When dealing with very small units, the metric system works very well, as values can be expressed with short, whole numbers, as well as with very large units.

  83. Gravitygate. I have been told that the universe is expanding at an increasing rate; I believe that as surely as I believe that the weight of the standard kilogramme has been declining, (whether or not it is true). It is therefore obvious to the meanest intelligence that gravity is a repulsive force, and that that force holds bodies like the earth and sun together, and gives masses on the earth their weight. As the universe expands, not only will the earth expand slightly but the weight of masses on its surface will decline. That has the advantage that, like H G Wells’s Pycraft, as I lose weight without losing mass, the strain on my heart is decreasing and I might live a microsecond or two longer.

    I have complete faith in this account, as I have faith that the universe was created in six days and is a jolly good thing, and as I have faith that AGW is true. I do not accept that I ought to listen to others just because they know much more physics than I do. Why should I? Faith avoids the onerous requirement that we reason. Please note that I have seen no need to generate computer models to prove my point – which is fortunate given my computing ability.

    It is plain that there is a conspiracy, which I call Gravitygate, to prevent the truth about gravity being noised abroad. I cannot believe that many others do not know the truth. Surely they do not fear looking stupid if they own up.

  84. Metrology is a problem between the US and Europe especially. We have all sorts of screw threads since Whitworth, but probably the most enduring standard is BSP, the British Standard pipe thread, although one needs a fair bit of knowledge to understand those threads (1/8″ BSP is very roughly equivalent to 1 cm in diameter, e.g., hence a wee bit illogical).
    The USA followed UK screw thread manufacture fairly closely, until they decided to make their own. The nut (bolt head) sizes may be the same, so you can use your “standard” a/f (across flats) socket set, but the screw threads may not now be so.
    The Europeans, on the other hand, have ‘screwed’ up things royally with their metric screw threads – not one, but two pitches (fine & coarse), and their own pipe threads, with a slightly different pitch angle.
    So, although I am conversant in degrees F to deg C, and vice versa; psi to bar, and vice versa, etc, etc, and all the various ramifications of different units, I am not ever sure of screw threads!
    The moral of this little tale is, I suppose, that you should always check your units of measurement. Failure to do so could result in either a very costly plant shut-down, or an explosion.

  85. Vince Causey and Slacko,

    2002 – The International Committee for Weights and Measures (CIPM) considers the metre to be a unit of proper length and thus recommends this definition be restricted to “lengths ℓ which are sufficiently short for the effects predicted by general relativity to be negligible with respect to the uncertainties of realisation.”

  86. Wait a minute, I thought the speed of light was an average???? Didn’t someone discover light travel at different speeds at different wave lengths/colors????

    The SI definition makes certain assumptions about the laws of physics. For example, they assume that the particle of light, the photon, is massless. If the photon had a small rest mass, the SI definition of the metre would become meaningless because the speed of light would change as a function of its wavelength. They could not just define it to be constant. They would have to fix the definition of the metre by stating which colour of light was being used. Experiments have shown that the mass of the photon must be very small if it is not zero

    http://www.phys.ncku.edu.tw/mirrors/physicsfaq/Relativity/SpeedOfLight/speed_of_light.html

    So which color did they choose? How about purple, I like purple…

  87. @dscott
    The speed of light in vacuum is independent of frequency (color/wavelength): light waves aren’t dispersive. That’s a direct consequence of Maxwell’s equations.

    @DesertYote
    I guess the metrologists are aiming at a very precise and fundamental definition of the unit of mass. The atomic mass unit (1/12th the mass of a Carbon-12 atom, which is more or less the average mass of a nucleon) is similar to your idea of the rest mass of an electron, but this does not seem to be fundamental enough. Perhaps because the mass of the electron is subject to renormalization due to electromagnetic self-interactions. Also, using nuclear radii to establish a length unit is not enough: even a proton (or electron) has not a well-defined radius, tough it has what is called a “classical radius”. The idea of radius of these entities gets rather fuzzy, once you get down to the quantum level. Finally, many photons would have problems going across a helium nucleus: for instance, a visible photon has a wavelength about four orders of magnitude greater than the average atomic radius.

    It seems to me that metrology is terribly subtle.

  88. Mooloo says:
    January 29, 2011 at 2:07 am

    If the US were persuadable by reason, they would be metric by now. Like the rest of the world.

    Now that’s what we Yanks call “doubling down on stupid.”

    Or, in metric, “tripling down on stupid.”

  89. Any kind of censorship and ideological persecution leaves a bad aftertaste in my mouth (especially when it is endorsed by the bad-mannered and self-proclaimed “world’s foremost specialist” in anything).

    In this regard, I would like to get an explanation of why, exactly, proponents of the certain (however ridiculous) “Electric Universe theory” are silenced here, while proponents of the much more ridiculous creationist “Big Bang theory” are given the green light.

    Is it that the Big Bang “consensus” (postulating that 98% of our Universe is a mystical cloaked matter, mysterious divine-like forces operating outside the laws of conservation of mass and energy, and other mythical epicycles and fudge factors that nobody can ever observe — just to fit reality to formulas) is somehow less fraudulent than the AGW “consensus”?

    If I don’t understand something here, I would like to be enlightened.

  90. “ktwop says: January 28, 2011 at 8:55 pm

    The metre is now the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second (with or without a gravity field?). A second is no longer connected to the length of a day and its sub-divisions but is now the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom at rest at a temperature of 0 K.”

    And have we ever been able to get to 0 K, let alone measure anything?

  91. Lots of great comments!

    Whitworth is the right system for what it was developed — steel fasteners.
    It has no meaning or rational basis outside of steel fasteners. Similarly the
    Morse taper system is great for steel tooling, and only steel tooling. For
    their domains, these systems are essentially perfect. (Sticking tapers,
    like Morse, need the closure angle tangent to be the coefficient of static
    friction of the target material.)

    Where Whitworth fails is in ease of manufacture. Relative to the similar
    60 degree thread system, Whitworth tooling is at least 10x as hard to make!
    Whitworth fails to be useful in aluminum. Thus the US was not interested
    in using a difficult-to-tool non-aluminum-compatible system for making
    airplanes in emergency mode in WWII.

    Do some research, and take a read through “The Measure of All Things”.
    The metric system was devised thusly:
    1) Choose a random galaxy, in it a random sun, near it a random planet.
    2) Make 7 attempts to measure a random section of the planet. Get tired
    of trying to measure. Give up and declare the job “done”.
    3) Translate the “done” number into some arbitrary numerical base
    4) Decide that the number, as represented in that base, is “too big”.
    5) Choose a semi-random set of prime numbers, 14 in all.
    6) Repeatedly divide “too big” by all these primes until the “just right”
    number is found.
    7) Choose a random substance on this random planet. Fill a 3-dimensional
    box of size “just right”^3 with the substance.
    8) Choose a second random substance on the random planet.
    9) Try 5 times to make a good copy of the same mass of random substance 1
    “just right”^3 in random substance 2. Give up, and declare the result a
    standard.
    10) Call the result a “standard kilogram”.
    11) Celebrate, and declare your standard to be obvious, universal, non-arbitrary,
    and very important. Insist on it!

    That, my friends, is a true summary of the Metric System. It is no less arbitrary
    than the width of my thumb, or the measure from the end of my nose to the end
    of my finger.

  92. Whenever proponents of any theory, however ridiculous, are censored out from any forum, I feel bad aftertaste.

    Especially if this action is supported by the self-proclaimed “world’s foremost specialist” in something, who himself is a proponent of a much more ridiculous theory called “Big Bang”.

    Talk about consensus. Some consensus bad, other consensus good?

  93. “Laurence M. Sheehan, PE says:
    January 29, 2011 at 12:47 pm
    I am familiar with the three systems, centimeter -gram-second (cgs), meter-kilogram-second (MKS) and foot-slug-second, used then.”

    Of course, cgs is now part of MKS, which is now SI.
    But what I would like to know: Energy in the foot-slug-second-system must be in pound(force)*foot, power in pound*foot/second, but what are the units used in electricity instead of Volts, Amps etc.?

  94. The universe is returning to the nothingness from whence it came. No big mystery. If the mass loss in that chunk of platinum continues at the current rate it’ll disappear completely in 2 million years.

  95. Re: “Whenever proponents of any theory, however ridiculous, are censored out from any forum, I feel bad aftertaste.”

    To some extent, I perhaps have to apologize for being too specific and wordy in my attempt to talk about mass and gravity on this climate blog. In this regard, my post was inappropriate.

    That said, I do believe that there must always be a place for discussions of electricity in space in discussions of weather and climate, because the two topics clearly intersect on many very important points. To think that we all spend so much time discussing the weather and climate of the Earth, without using our observations of other planets’ circulation systems in our solar system as a test for these models, I think shows that we are overly-compartmentalizing the climate modeling issues to suit our pre-existing views on climate.

    I am very accustomed by now to being the ugly duckling in the forum world. I am extremely familiar with the widespread hostility towards any theory which proposes that electricity in space does things of great importance. The challenge I regularly face is in fitting these arguments into the format which is demanded by related blogs.

    In my own personal view, the problem of modern science is increasingly a human problem: We restrict our reading to suit our pre-existing belief systems. And, for whatever reason, the further one climbs the scientific ladder, the less that anyone can force that person to read something which they already disagree with. This is a major problem, as it facilitates the problem with formulating a complete set of inferences for our observations.

    I understand that Anthony depends upon a healthy conversation here on these blogs. But, I would also ask everybody to realize that the complaints of conventional theorists and scientists have single-handedly blocked a more widespread dispersion of the Electric Universe arguments for a couple of decades now. The pattern by now is set in stone: Documentaries are always ditched at the point where a third-party scientist is asked to vet the video. It is these behind-the-scenes politics which lend the impression to the public that this debate is something which we can safely dismiss.

    And yet, IEEE’s Transactions on Plasma Sciences continues to publish on this subject (IEEE is the world’s largest scientific institution, btw). And those who follow along with my arguments will notice that few of the pressing controversies which I bring up are ever responded to by conventional thinkers. They are generally ignoring them.

    After all, we now know that magnetic fields are observed to permeate the largest scales of the universe. In the laboratory, electric currents are the first logical inference for such an observation. But, in space, it is the one inference which is out of bounds and not taken seriously for papers submitted to the Astrophysical Journal.

    In the EU view, the Earth’s weather and climate is a product of its heliospheric plasma environment. Water is a dipolar molecule, which means that it is subject to electromagnetic forces. It is also clearly an excellent conductor — which on large scales facilitates the movement of charge between Earth and space. These moving charges can do all sorts of important things. They can, for instance, drag neutral matter, in the process creating wind.

    To ignore these things — which by themselves should not be incredibly controversial — we’d be serving an ideology which limits the role of cosmic electricity. I think that some of the readers of WUWT have already reached this point of realization — even if Anthony has not.

    The notion that we should all agree on our assumptions — the cosmological framework of the Big Bang, Standard Solar Model, etc. — in our discussions of weather and climate is not based upon any philosophy whatsoever. The cosmology is by definition in fact the weakest portion of our entire system of scientific thought. Surely, we can all agree on this point.

  96. Unless I have overlooked a post, I am shocked that nobody has brought up the bizarre incident of the moon rover robot whose initial problems were alleged to have been caused by some of the engineering being done with the metric system and the rest done in “American”. I don’t know if this was true or not, but it was widely reported at the time and caused NASA a lot of embarrassment.

  97. Unless I have overlooked a post, I am shocked that nobody has brought up the bizarre incident of the moon rover robot whose initial problems were alleged to have been caused by some of the engineering being done with the metric system and the rest done in “American”. I don’t know if this was true or not, but it was widely reported at the time and caused NASA a lot of embarrassment.

    http://articles.cnn.com/1999-09-30/tech/9909_30_mars.metric.02_1_climate-orbiter-spacecraft-team-metric-system?_s=PM:TECH

  98. Self referencing in definitions is always going to be a problem. If the kilo reference has changed, the kilo has changed. If the speed of light has changed, the length of a metre has now changed. If the time it takes for an electron to orbit an caesium atom changes, our definition of a second changes.

    How is it determined that the references the definitions are based on aren’t themselves changing? In this case it has obviously been noted somehow that there has been a small change in the reference – how?

  99. If the metric system was really so great and easy to understand, users would say something weighs so many Newtons.

    When we say how many pounds something weighs, at least we’re using the correct units for the system. ☺

  100. >>>>Enchamp… The moral of this little tale is, I suppose, that you should always check your units of measurement. Failure to do so could result in either a very costly plant shut-down, or an explosion.

    Or a Boeing 767 to run out of fuel in midflight…. Anyone here remember the Gimli Glider incident in 1983?

    http://en.wikipedia.org/wiki/Gimli_Glider

  101. It used to be, 40 years ago, that the kilogram was defined (in school) as the mass of one liter of H20 at STP. One liter being defined as the volume created by a 10 centimeter cube and one centimeter as 1/100,000,000 of 1/4 the Earth’s diameter.

    The origins of the meter go back to at least the 18th century. At that time, there were two competing approaches to the definition of a standard unit of length. Some suggested defining the meter as the length of a pendulum having a half-period of one second; others suggested defining the meter as one ten-millionth of the length of the earth’s meridian along a quadrant (one fourth the circumference of the earth). In 1791, soon after the French Revolution, the French Academy of Sciences chose the meridian definition over the pendulum definition because the force of gravity varies slightly over the surface of the earth, affecting the period of the pendulum.

    Thus, the meter was intended to equal 10-7 or one ten-millionth of the length of the meridian through Paris from pole to the equator. However, the first prototype was short by 0.2 millimeters because researchers miscalculated the flattening of the earth due to its rotation. http://physics.nist.gov/cuu/Units/meter.html

    The whole point of the kilogram was that is was unit of MASS not weight. The problem is gravity changes over time and from place to place, so any 50 mircograms of change/weight could easily be accounted for on Earth a change in gravity. You can claim all day long that you are measuring mass BUT on earth you are weighing something in a gravity field and I don’t care how fancy your equipment is or what technobabble you come up with you are still WEIGHING the object even IF it is against a reference mass.

    This is a tempest in a teapot. Stick with what you got and go with it otherwise all your previous measurements are worthless. You do know there is such a thing as significant digits and we used that math concept with sliderules to get to the moon.

  102. Slightly off Topic but I have to share…
    I told my 8 year old that we will be getting a foot of snow on Tuesday. He looked at me with a serious face and asked “My foot or your foot”.

    Long live man-defined-measurement. If a meter is the distance light travels in a vacuum in 1/299,792,458 of a second. One has to ask how accurate is a second?

  103. Every measurement compares an ‘unknown’ with a ‘reference’ (even if it is your thumb); so fundamental mass measurement always involves a ‘beam balance’ comparator, with two pans and a central pivot to compare two Pt-Ir cylinders. Visit the BIPM website to see just how carefully they do it with le Grand K.

    2. The BIPM website gives a very full description (with colour photographs) of the ‘cleaning process’ applied to every pair of prototype Pt-Ir ‘std’ kilogram masses before any two of them are compared with each other.

    3. Changes due to cleaning are obvious candidates for observed ‘variations’ in the differences between any selected pair of ‘std’ 1.000000±0.000025 kg masses over any 40 year period. Gravity is not, because, by definition, a beam-balance comparison places the compared masses at the same place and time when each comparison is made.

    For crying out loud, it’s only 50 micrograms in 1000 grams, over 100 years, and of no practical significance in any actual measurement program anywhere in the world. It’s not a serious problem! [Not like trying to cut 0.01 C per CENTURY off the average slope of a temperature anomaly calculation, based on dubious quality temperature measurements].

  104. If the US were persuadable by reason, they would be metric by now. Like the rest of the world.

    Now that’s what we Yanks call “doubling down on stupid.”

    Or, in metric, “tripling down on stupid.”

    Merovign has evidently not ever had someone give him moment of inertia, variously, using ounces of force, ounces of mass, lbs of force, lbs of mass, and distances in feet or inches, depending on who it was and how they felt on a given day.

    Occasionally you see mass given in slugs. But that’s rare. In my decades-long conversion to metric aficionado, I can count the number of times I’ve seen Newtons used as a unit of force on the toes of my hind feet.

    I’d want to know more about how they’re measuring mass before I started jumping to conclusions, here.

  105. “”””” Smokey says:
    January 28, 2011 at 5:08 pm
    Measuring mass at the microgram level is much more difficult than it would seem. Mass is often confused with weight, but they are not the same. “””””

    Prior to the two most recent America’s Cup contests, a series of pre-events were held to keep sailor, and team sponsor interests alive and gather points towards deciding the Challenger to the then current Cup holder; Swiss Alinghi Team.
    The first Regatta was held an the Mediterranean off Spain.
    Part of qualifying the boats, involved verifying the wieght of the boats. Teams wanted to run their boat up to the maximum weight limit, to have available the maximum righting moment from the lead keel bulb.

    Following that regatta, the next set of qualifying races was set for Malmo, in Sweden (snake eyes over the ‘o’ ); which happens to be at 58 deg 21′ North latitude, so it is far enough North to be major affected by the oblateness of the earth, so (g) is higher in Malmo.

    Every single boat in the fleet failed the weight limit remeasure. The dummies that wrote the roolz, specified the Weight limit for the boats, rather than specifying a Mass limit. Don’t remember how they resolved the fox pass; whether they waved the transgressiosn, or made everybody cut a piece off their boat.

    Emirates, Team New Zealand, ended up challenging the Swiss for the cup, and sort of blew a contest they should have won; but a successful defence to the Alinghi Team.

  106. “”””” V in PA says:
    January 31, 2011 at 6:24 am
    Slightly off Topic but I have to share…
    I told my 8 year old that we will be getting a foot of snow on Tuesday. He looked at me with a serious face and asked “My foot or your foot”.

    Long live man-defined-measurement. If a meter is the distance light travels in a vacuum in 1/299,792,458 of a second. One has to ask how accurate is a second? “””””

    The definition just given means that (c) is 2.99792458 x 10^8 m/s

    That number is exact by definition. The second is defined in terms of the frequency of the emission due to a specific transition in 133Cs; specifically between the hyperfine structure levels of the Ground State; which is 9,192,631,770 periods at that frequency. It is considered accurate to a part in 10^14, which is good enough for most sports events.

    Since (c) = 1/sqrt(mu_nought x epsilon_nought); and mu_nought is 4pi x 10^-7 V.s/A.m (Volt. sec/Amp. metre) which is exact; then epsilon_nought = 8.85418781762 x 10^-12 A.s/V.m must also be exact (and is).

    It used to be that the second was defined in terms of the frequency of one spectral line (as now) and the metre was defined in terms of the wavelength of another spectral line ( in 86Kr I think), so (c) was dependent on a comparison of those two lines.

    But now (c) and the electric constants which give (c) from Maxwell’s equations, are defined exactly.

  107. “”””” dscott says:
    January 30, 2011 at 8:01 pm
    ………………..
    The whole point of the kilogram was that is was unit of MASS not weight. The problem is gravity changes over time and from place to place, so any 50 mircograms of change/weight could easily be accounted for on Earth a change in gravity. You can claim all day long that you are measuring mass BUT on earth you are weighing something in a gravity field and I don’t care how fancy your equipment is or what technobabble you come up with you are still WEIGHING the object even IF it is against a reference mass. “””””

    Well actually you are comparing the gravitational attraction between the earth and each of the standard mass, and the test mass. Yes it is true that if you do this with a beam balance, the two masses are in different places in that “gravitational field” you mentioned. That problem is trivially solved by providing an electromagnetic field to cancel the weight of the standard mass, and then swapping the two masses, and comparing the EM field comparison. So now the two masses are in exactly the same gravitational field, and the em field can be set in the same center of mass location in that field.

    Weight unfortunately is not a very good measure; well just the sloshing around of the oceans, must perturb the weight due to varying accelerations of water masses.

    I have “weighed” the entire earth myself; and it typically runs in the range of 180 pounds avoirdupois. You can do it yourself; but you likely will get a different answer from mine.

    You need a plane mirror, and a stout bucket or footstool; well you also need a bathroom scale to weigh the earth on.

    So you put the plane mirror on the floor face up, alongside the footstool or bucket (upturned); and then you place the bathroom scale on top of the footstool; upside down so you can read the scale in the mirror. When I do this I get some totally chicken**** weight for the earth of about 2-3 pounds.

    So then I climb up and stand on top of the upsidedown scale, to add some stability to the system, and peer over the edge with my computer glasses on so I can read the scale upside down. Right now it reads about 177 pounds; but more often, than not, it reads 182 pounds.

    The weight of the earth is highly variable, and not something you can depend on for anything.

  108. “”””” Alexej Buergin says:
    January 29, 2011 at 11:23 am
    I have yet to meet an American who can tell me
    1) how many feet to a mile
    2) how many square-feet to an acre
    3) what a pound is, and what is measured by it
    4) how many Watts in a horsepower
    5) the unit one measures blood pressure in
    All very simple if you know metric. “””””

    Well Alexei; I’m an American, and without googling or yahooing, or wikipiddling, I can guess the following answers to your questions:-

    #1 5280 ft per mile.
    #2 43560 squ ft per acre, or 4840 squ yds if you like.
    #3 As they say; “a pint of water weighs a pound and a quarter”, except in the USA, where they say; “a pint’s a pound, the world around.” which of course it isn’t at all. And it measures both the mass and the weight of a body under the assumption of a standard acceleration due to gravity (g) of 9.80665 m/s^2, which I believe is the value accepted for sea level at about +45 deg North Latitude. Various conventions would dictate using “pound” if referring to mass, and “pound weight, if meaning the weight of a pound (mass). Then one could mention the “poundal” which would be defined loosely by saying the weight of one pound (mass) is (g) poundals.

    #4 a horsepower is 746 Watts.

    There is of course the Troy Ounce used in precious metals, and jewellery; but I have never seen anybody’s definition of a Troy Pound; or even if there is such a thing.
    #5
    Now I don’t know diddley squat about the units for blood pressure; all I know is that my units are different from everybody elses; and they roam all over the map. My doctors think I am a transitionary specimen somewhere in the gap between homo sapiens sapiens; and whatever species we are evolving into; they also say it isn’t a problem; just abnormal.

    But now Alexei; I would like to trump your ace.

    Please explain to us; slowly if you will, since some of us are quite dense;

    Exactly how does “knowing the metric system” enable one to computet “the number of square feet in an acre” ?

  109. From Alexej Buergin on January 29, 2011 at 11:23 am:

    5) the unit one measures blood pressure in
    All very simple if you know metric.

    Millimeters of mercury, mmHg, with 1 mmHg approximately equal to 1 Torr, which is defined as 1/760 of an Atmosphere (atm). It is a rather unscientific unit, deserving of ridicule. From the Wikipedia Torr entry:

    Manometric units are units such as millimeters of mercury or centimeters of water that depend on an assumed density of a fluid and an assumed acceleration of gravity. The use of these units is discouraged.[6] Nevertheless, manometric units are used routinely in medicine and physiology, and they continue to be used in areas as diverse as weather reporting and scuba diving.

    The millimeter of mercury (symbol: mmHg) is defined as the pressure exerted at the base of a column of fluid exactly 1 mm high, when the density of the fluid is exactly 13.5951 g/cm3, at a place where the acceleration of gravity is exactly 9.80665 m/s2.[7] Under most conditions, 1 mmHg is approximately equal to 1 Torr.

    There are several things to notice about this definition:
    * A fluid density of 13.5951 g/cm3 was chosen for this definition because this is the approximate density of mercury at 0 °C. The definition, therefore, assumes a particular value for the density of mercury. The density can depend on temperature, exogenous pressure, and other similar variables, so those have to assume certain conventional, normal values as well.
    * The definition assumes a particular value for the acceleration of gravity: the standard gravity g0 = 9.80665 m/s2. In theory, the precise acceleration would vary, and the measurement would have to be recalibrated against the local value; in weightless conditions, this kind of measurement would not even make sense.
    * The definition does not address the quality of the vacuum, including the vapor pressure of the mercury, above the column of fluid.

    Pounds per square inch (psi) is a far more scientifically valid unit.

  110. Chris Reeve says:
    January 30, 2011 at 11:28 am
    Re: “Whenever proponents of any theory, however ridiculous, are censored out from any forum, I feel bad aftertaste.”

    To some extent, I perhaps have to apologize for being too specific and wordy in my attempt to talk about mass and gravity on this climate blog. In this regard, my post was inappropriate.
    ———————————————————————————–
    Chris:

    Think twice before bringing up your theory. There was a guy on here once who was warned many times, about his pet ‘Iron Sun’ theory. It would show up in dicussions about why French officers wear brown pants(so their felllow officers don’t see them panicking!!!). He would inject it into every discussion if (usually only) he felt it was remotely relevant. He couldn’t help himself. I’ve seen the Electric Universe discussed here at WUWT ad bbc2(can’t spell neuseum!). Your chance will come….again….and again and you’ve discussed it before. When it’s patently related to the subject, you’ll have no problems. A life time ban stares you in the face.
    because you are not listening.
    Anthony doesn’t have time to keep repeating himself. I’d go back through the archives and see all of Leif’s responses to all the EU stuff. And figure out how better to present the ideas more convincingly. Some data would help too.
    Fair warning?

    As for the French: can’t they do anything without taxing it!

  111. Somewhere around early 1990 an intern cleaned the standard with ordinary paper towels.
    He was the boss’s nephew so it was kept quiet.
    They didn’t think anyone would notice a few scratches.
    The intern, later that year worked as a janitor at NASA on the hubble telescope project. :P

  112. My instinct says it is from the “Hydrogen in Metals” effect. The Hydrogen might be acting as a solvent.

    Platinum is exactly the class of metals that is subject to this phenomenon, along with Palladium.

    Metallic suboxides dissolve Hydrogen, but that means the metal is being affected, too. At least I think so.

    I am amazed at how many people commenting here have talked about the accuracy of the measuring or metrology itself (even to screw threads!). I am sure that the measuring itself is the first thing the IBWM looked at and wouldn’t be outing this problem without eliminating other possibilities (as opposed to AGW fans, for example).

    Tim Folkerts January 28, 2011 at 7:46 pm:

    Michael says: “I thought a kilogram was defined as the mass of a litre of water. ”
    That was the original definition, but that has not been the official definition of a kilogram for a looooong time.

    Actually, I believe it was a litre of water at 4°C. And I am pretty sure the litre of water was defined as 1,000ccs, which themselves were defined as 1,000 drops of water at 4°C. As such, the liter was not a volume, but a number of drops of water. At least that is what I recall.

    Engchamp January 29, 2011 at 2:20 pm:

    Metrology is a problem between the US and Europe especially. We have all sorts of screw threads since Whitworth, but probably the most enduring standard is BSP, the British Standard pipe thread, although one needs a fair bit of knowledge to understand those threads (1/8″ BSP is very roughly equivalent to 1 cm in diameter, e.g., hence a wee bit illogical).

    If by “we” you mean in the U.S., having worked in mechanical engineering for 39 years, I can tell you BSP is not enduring in any companies I’ve ever worked with, threaded pipe with BSP threads is quite uncommon. NPT (National Pipe Thread) is the U.S. standard.

    The Europeans, on the other hand, have ‘screwed’ up things royally with their metric screw threads – not one, but two pitches (fine & coarse), and their own pipe threads, with a slightly different pitch angle.

    Also wrong. The U.S. does, in fact, have two pitches. The standard in the U.S. is Unified Threads, and screws and nuts come in both UNC and UNF – Coarse and Fine – and both are very available in every hardware store and supply house.

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