zugmann "The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it!"-Abe Simpson
"The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it!"-Abe Simpson
It is the devil's work. Having it introduced into everyday life of those familiar with the English system creates mind-boggling havoc. The airplanes I worked on for a living are still called out in English units of measurments. Can't say the same for cars. Methinks it was a plot on the part of tool manufacturers.
Norm
I'm surprised the cubit hasn't come up (or did I miss it?)
Or the "stone."
BTW - 40 rods per hogshead is pretty abysmal mileage.... My truck gets about 670,000 rods per hogshead...
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
"The metric system is the tool of the devil! My car gets forty rods to the hogshead and that's the way I likes it!"
-Abe Simpson
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.
VOLKER LANDWEHR I can't understand the reason and use of human-scale measurements.
I rest my case.
RMENow you are putting words in my mouth to say something just the opposite of what I was discussing. Are you by some chance a climate scientist? Big Smile
Perhaps I misunderstood you. Thats quite easy in foreign language. But among others you said: "The meter is too long; the millimeter too short, the degree C too coarse without a decimal, the unit of pressure almost hopeless ... the scheme takes little interest in human-scale units. Sure, there is the decimeter ... but that's deprecated under SI (which is different from cgs or mks measurements)."
I didn't intend to put words in your mouth.
I'm a civil engineer (structural design) having worke my whole professional life with [mm] (steel structures) and[m] (concrete structures). I can't follow the above cited thoughts. I can't understand the reason and use of human-scale measurements.
RMEAn international convention that standardized on a legitimate human-scale metric, like an "inch" at 2.5 "cm" could easily resolve all that petty stupidity at a stroke.
But what for. The meter could easily be the standard too.
RMEThe reason I dislike the 'meter', to make it a bit clearer, is that it pretends to be a logically-derived number when most of its history plainly indicates it is essentially pseudoscientific in any "natural" derivation from human measurements made for human purposes.
I'm sure you know that the definitions of kilogram and second are similar arbitrarily. As is inch.
Reading my post I think I really don't understand your intentions.Regards, Volker
Thankfully there's significant figures that can come to the rescue.
VOLKER LANDWEHRYou do not like the meter because of its definition but you like inch and yard?
Now you are putting words in my mouth to say something just the opposite of what I was discussing. Are you by some chance a climate scientist?
What we were discussing was human-scale units; more specifically the amusing use of very large quantities combined with very small quantities that happen to produce a human-relevant metric.
Many of my European friends try to trot out that tired old "whose inch do you use" without recognizing it is European inches and national prides that were the root of the problem in the first place. An international convention that standardized on a legitimate human-scale metric, like an "inch" at 2.5 "cm" could easily resolve all that petty stupidity at a stroke.
Because the problem ... and it is a problem ... is that the meter is too long to be a practical measure of human scale, just as the yard is -- and no, I don't favor 'yards' over 'meters' except incidentally, as a whole-number multiple of a foot. Meanwhile, 'as it happens' the length of an average human thumb is not a multiple of 10 ... let alone a multiple of 1000 ... of a human foot.
I have always liked a couple of intermediate units like the span and the cubit, the former, incidentally, corresponding rather well to the decimeter (which, as noted, the European foolish-consistency-lovers try to deprecate out of existence) and the latter coming reasonably close to a half-meter.
Proof of the fundamental confusion, if you want to trot out all those wack inches, is that the fundamental unit notation in the metric system is contradictory. It ought to be defined in terms of fundamental units, so let's look at meter-kilogram-sec... oh, wait, that's a derived unit. So we use the scientific convention which uses grams to solve that problem, centimeter-gram... oh wait, that still doesn't work, and I hear cries from the general direction of Bienne that the derived unit of length is supposed to be 'withering away'. Consistency demands meter-gram-second, which is just as "consnstent" and "internationally defined" as your arguments try to be saying, but the results of calculations would have the very worst lose-one-decimal-place-with-all-the-shifting-and-your-lander-hits-Mars-too-hard lack of instinctive proportion that I was actually discussing as being a problem with the meter.
The reason I dislike the 'meter', to make it a bit clearer, is that it pretends to be a logically-derived number when most of its history plainly indicates it is essentially pseudoscientific in any "natural" derivation from human measurements made for human purposes. And then we get people who try to claim that just because its system is base-10-consistent, it is necessarily better even for human-scale measurements - the latter extension being where I have the problem with the validity of the 'you were holding it wrong' style of argument.
erikemNot octal??? I was a fan of the big Cray designed CDC machines....
Odd number of binary digits. And shorter/more digits required than decimal. Why cut off two fingers to accord with obsolete computer conventions?
And the systems that go to longer word boundaries (32-bit, 64-bit, etc.) begin to be a bit Sumerian in the number of special characters required.
Quite a bit of the thinking was expressed better than I could do it back in the time of introduction of 16-bit processors.
Electron-volts is a wee tad mis-scaled for human temperature ranges, but this could be accommodated as simply as the metric/SI system does human-scale pressure changes: denominate a multiples unit as the general range of measurements and 'standardize' on the decimal conventions that zero in on it. If it is consistent, easy to memorize, and provides decent approximation to the scale of fine gradation in everyday contexts, you have a contender.
Of course, Celsius and Fahrenheit are relatively equally unsuited for scientific use because they are relative; the 'correct' units are degrees Kelvin and Rankine respectively. And here the 'centigrade' unit width makes things a bit better, because everything at human range and relative precision is large, but less large than degrees R, and requiring a decimal is no more or less of an issue given that magnitude.
The IxD of some of the European derived units is not quite thought through. Take for instance the 'unit' of specific fuel consumption per distance run. In the English system, this looks at the desired unit (the distance the vehicle runs) divided by the fuel used, and the result properly gets larger for better end result. The Germans emphasize the fuel consumed, which looks sensible if you are going directly to fuel cost for known runs, but then spoil both the sense and the SI consistency by defining the "mileage" in terms of 100km, which requires a division to get an answer that means more than a guide number, produces numbers with significance in decimal places. Yes, it's consistent in getting smaller with lower consumption, but the numbers get smaller and give you no instinctive grasp of how far you can go on the fuel you have unless you are very, very familiar weith discriminting small decimal numbers.
@RME: I just wanted to clarify the historical order of the events around the meter without any judgement. But perhaps I just misunderstood your post.
The topic seems very emotional to you. So I just comment some -in my point of view - discrepancies.
You do not like the meter because of its definition but you like inch and yard?
The inch started as three barley corn in a row in the UK and is now defined as part of the meter same as yard and feet.
You seem to prefer units based on phisical constant but prefer degree Fahrenheit over degree Celsius. In both systems you need decimals to describe the human body temperature. 96°F are too low and 100°F is feaver.
I think we all prefer what we grew up with. One system is not necessarily better than the other. For me as an engineer the system must be workable and that the SI system was.
BTW thanks for the word derive.
It nice to see all those alternatives. But the definitions were necessary at a time when these constants weren't know. Before the introduction of the meter there were different length unit in almost each principality.Regards, Volker
A brief but nonetheless excellent essay on many of these points:
- PDN.
I'm not going to complain too vociferously about using a centigrade system founded in phase changes of water because it needs decimals to describe the range of human temperatures adequately: I in fact find decimal adjustment of the comfort zone on a Fahrenheit thermostat useful for adjustments around 'room temperature' (say. 68 to 72 degrees or so) just as I do for fever-thermometer gradations in that system. But to require a decimal notation to discriminate wider effective ranges of temperature, and to have the range of body temperature in an arbitrary range of the chosen unit, is not so bright if the system is to be as useful to humans as something like the Modulor was meant to be.
I've always wondered about what was so special about having 100 divisions between the "freezing" point of water and the temperature of water when the vapor pressure that can't be expressed as a simple round number in any unit except "atmospheres" (well maybe torr). Getting an accurate calculation of heat energy involves looking up a table of some sort for any combination of units.
My vote for unit of temperature would be electron-volts, but that gets very messy in relationship to human comfort...
The crowning jewel in the nonsense, for me, is the conversion from grays to sieverts, involving as it does a factor of 100 that is not supposed to be supported. There are facile explanations for this, but none that really get around the cognitive dissonance.
Roentgens/RADs to Grays? 1 Sv = 100 REM - I always convert Sv to REM as my memory of significant dose milestones is in REM or mREM.
Personally, I'd like to see the number system itself revised to hexadecimal, but I don't expect that to get much more traction than 18th-century decimal time.
Not octal??? I was a fan of the big Cray designed CDC machines....
VOLKER LANDWEHRThe first proposal for the meter was the described pendulum in about 1668. But the French Academy of Science decided to choose the form of the earth as a base in 1791
Because, as I said, they didn't want to use the old 'second' because of the wacky switch to decimal time. Mercifully that wasn't foisted on the West, or that ridiculous decimal calendar scheme, either.
The meter was the one ten-millionth part of the longitudinal length North-Pole to Equator through Paris.
Measured incorrectly, in a direction that involves the oblateness of the Earth's shape (in a way that an equatorial circumferential measurement wouldn't ... but then it wouldn't pass through Paris...)
They built prototype meter bars that were used as definition. Sometime the realization set in that aging might change the prototype meter and duplicating might be faulty. So a definition was looked for which described the length of the prototype meter bar with firm physical characteristics...
And that is why the 'universal' (artifact-free) definition from 1960 to 1983 was a frequency of krypton-86 light ... ending in a decimal fraction of a wavelength! It was the length of the historical platimum-iridium artifact at BIPM that was, and is, the determinant of 'how long a meter is'.
And the real problem is, once the base of the system is no longer a legitimate universal physical constant, there is no use claiming it is 'logical' because it is merely divisible by the number of dactyl appendages on the inventors -- which is OK, but the decimal-inch system used by American machinists does this perfectly effectively, much more compellingly than, say, measuring the wheelbase of large steam locomotives in millimeters (of which silliness much more anon).
The meter is too long; the millimeter too short, the degree C too coarse without a decimal, the unit of pressure almost hopeless ... the scheme takes little interest in human-scale units. Sure, there is the decimeter ... but that's deprecated under SI (which is different from cgs or mks measurements).
Now, if you're raised to know no better, you can of course get used to inconvenient units. I'm sure there are plenty of people who are used to European tolerancing conventions, which I find ridiculously overcomplicated for the practical use people need to use a tolerancing system for. I'm not going to complain too vociferously about using a centigrade system founded in phase changes of water because it needs decimals to describe the range of human temperatures adequately: I in fact find decimal adjustment of the comfort zone on a Fahrenheit thermostat useful for adjustments around 'room temperature' (say. 68 to 72 degrees or so) just as I do for fever-thermometer gradations in that system. But to require a decimal notation to discriminate wider effective ranges of temperature, and to have the range of body temperature in an arbitrary range of the chosen unit, is not so bright if the system is to be as useful to humans as something like the Modulor was meant to be.
The fact that the 'time' involved does not fit into the groups-of-three SI framework applied to time in seconds, and would hence be deprecated, is a mere intellectual bagatelle Could you please elaborate?
Gladly. SI at some point adopted the convention that any unit that is not a multiple of three away from the base unit 'shouldn't be used', with decimals forward and backward (and presumably significant figures whether actually 'significant' in the mathematical sense or not to match) in the coefficient being used to make the transition. This is why the measurements of long objects like locomotives are found denominated in mm, instead of something more sensible like cm or dm -- and why the official support for cgs, the system that chemists and other scientists called the 'metric system' for so long, is a kind of double-think for the SI people.
The crowning jewel in the nonsense, for me, is the conversion from grays to sieverts, involving as it does a factor of 100 that is not supposed to be supported. There are facile explanations for this, but none that really get around the cognitive dissonance. Now, note the relevance to the context of using a light-second as the definition of a length; SI either requires meters or mm for that length (and the current BIPM definition, I think, may actually have it in km; I'd need a pencil and paper and see defined units for that facile divisor number, but the magnitude seems right). Neither of those does what IslandMan's light-nanosecond does (with a wholly coherent SI rule-of-three division!) or what an attoparsec does, which is a human-scale unit of measurement that is actually at some human scale.
I understand that there are currently seven basic SI dimensions that can not be deviated [note: I think the English word you want here is "derived"]by [from] multiplication of other SI-dimensions: meter, kilogram, second, ampere, kelvin, mole, candela.[/quote]
I think that is right, but I see no particular difficulty in fixing "accepted" values for these as the community has done (however, the way SI originally tried to do this with the second was something of a comical disaster, reminiscent of the Bangalore software development in YahooGroups "/neo/"). In my opinion there is great sense in defining chemical quantities in gram-molecular weight as this can be done to any necessary precision and no one is expecting these to be human-relatable magnitude, or fixing a unit of technical light measurement that as defined does not have to be used to compare or gauge direct human experience.
Discussions of human haptic incompetence in gauging the magnitude of numbers represented by large exponents is well established. As has human difficulty in relegating important discrimination of quantities to the decimal part of their numerical base-10 representation.
“Lieutenant Grace Hopper codes problems onto punch tape for feeding into a new calculating machine invented by Commander Howard H. Aiken, USNR. The calculator will be presented to Harvard University by IBM Corporation, for use by the US Navy for the duration of the war. The machine is a revolutionary new electrical device of major importance to the war effort. It will explore vast fields in pure mathematics and in all sciences, previously barred by excessively intricate and time-consuming calculations. Two years of research were required to develop the basic theory behind the giant calculator. Six years of design and construction and testing were necessary to transform Commander Aiken's original conception into the completed machine at the engineering laboratory of IBM in Endicott, N.Y.” Aug. 4, 1944
“Rear Admiral Grace M. Hopper salutes crew members as she comes aboard the U.S.S. Constitution in Boston's Charlestown section for her retirement ceremony. Hopper, the U.S. Navy's oldest commissioned officer on active duty, retired after serving over 40 years in a Navy uniform. The 188-year-old U.S.S. Constitution is the oldest still commissioned warship afloat in the world.” Aug. 14, 1986
Norm,
the discussion will go on until the last country switches to SI-unit. Having had a decimal system before the switch was quite easy for us.
I started as an civil engineer in the pre-SI-unit era. I'm in model railroading following American prototypes since the early 1980s. So I'm quite used to imperial measures.
For industry and trade one single system might be better. But I think humans would find measures to erect new hindrances.
I get along with both systems, for sure better with the decimal system.
Perhaps I didn't understand RME's post correctly. So I posted some details about the meter definition and its history.
I don't understand RME's statement "The fact that the 'time' involved does not fit into the groups-of-three SI framework applied to time in seconds". Therefore the list of basic SI-units.
Volker,
I suspect the dialogue and dissention over measurement systems will last a long time. I once had a phone call with someone in Canda after they made the switch to Celsius. She asked me the temperature where I was and I gave he Farenheit temperatuer. She asked why we weres still using that "old scale" and I replied that it was a better indicator of comfort than Celsius.
RME if the humans involved are dyspeptic inmates of an orphanage for dwarfs [sic].
if the humans involved are dyspeptic inmates of an orphanage for dwarfs [sic].
I find you guilty of spending too much time reading Lucius Beebe.
The first proposal for the meter was the described pendulum in about 1668. But the French Academy of Science decided to choose the form of the earth as a base in 1791. The meter was the one ten-millionth part of the longitudinal length North-Pole to Equator through Paris.
They built prototype meter bars that were used as definition. Sometime the realization set in that aging might change the prototype meter and duplicating might be faulty. So a definition was looked for which described the length of the prototype meter bar with firm physical characteristics, in the end the speed of light.
But it is still the same length.
RMEThe fact that the 'time' involved does not fit into the groups-of-three SI framework applied to time in seconds, and would hence be deprecated, is a mere intellectual bagatelle
Could you please elabotate? I understand that there are currently seven basic SI dimensions that can not be deviated by multiplication of other SI-dimensions:meter, kilogram, second, ampere, kelvin, mole, candela.Regards, Volker
IslandManOne of the arguments put forward for decimalisation is that it is somehow more 'rational' than feet, miles etc. In fact the kilometre was originally defined as a proportion of the Earth's circumference - too bad that that neat definition was neither accurate nor constant!
One of the problems was that the kilometre referenced to geodesy was originally defined as 1/4 of a defective measure of the Earth's circumference longitudinally measured at Paris, France. It went downhill from there.
The original "rational" measure, before the French (we might gainfully remember this was the same French who 'gamed' the phlogiston discussions at around this same era) started overthinking it by wanting wack decimal time, was the length of a pendulum beating exactly 1sec at sea level on the Equator, which has the immediate and powerful advantage of being quickly and easily replicatable by anyone with access to standard equipment at the Equator, and with reasonable ease derived from relatively straightforward period calculations elsewhere on Earth's surface.
I think linking the foot to the distance light travels in a vacuum is about as constant as it's possible to be.
In fact, the current definition of the meter has come 'full circle' and is now related to ... the distance light travels in a particular time. (The fact that the 'time' involved does not fit into the groups-of-three SI framework applied to time in seconds, and would hence be deprecated, is a mere intellectual bagatelle compared to other frank inconsistencies in SI)
erikem IslandMan Personally I use light-nanoseconds for measuring things. 1 foot = distance light travels in 1.0167033621639674471063578257196 nanoseconds. (With thanks to the late Admiral Grace Hopper) Too bad that the speed of light wasn't more accurately measured in Thomas Jefferson's time, the light-nanosecond would have made for a dandy decimal measurement system that could be established in any well-enough equipped laboratory. (Of course there were no such laboratories in existence at tha time.)
IslandMan Personally I use light-nanoseconds for measuring things. 1 foot = distance light travels in 1.0167033621639674471063578257196 nanoseconds. (With thanks to the late Admiral Grace Hopper)
Personally I use light-nanoseconds for measuring things.
1 foot = distance light travels in 1.0167033621639674471063578257196 nanoseconds.
(With thanks to the late Admiral Grace Hopper)
Too bad that the speed of light wasn't more accurately measured in Thomas Jefferson's time, the light-nanosecond would have made for a dandy decimal measurement system that could be established in any well-enough equipped laboratory. (Of course there were no such laboratories in existence at tha time.)
One of the arguments put forward for decimalisation is that it is somehow more 'rational' than feet, miles etc. In fact the kilometre was originally defined as a proportion of the Earth's circumference - too bad that that neat definition was neither accurate nor constant! I think linking the foot to the distance light travels in a vacuum is about as constant as it's possible to be.
RME IslandMan Personally I use light-nanoseconds for measuring things. 1 foot = distance light travels in 1.0167033621639674471063578257196 nanoseconds. (With thanks to the late Admiral Grace Hopper) A similar approach to human-scale units is the attoparsec (and its associated measure, attoparsecs per microfortnight). Note that the latter metric is also very close to a nanocentury / pi. I first found a couple of these when, in disgust, I first looked at studying Corb's Modulor system, which purported to define architectural proportions in human scale - if the humans involved are dyspeptic inmates of an orphanage for dwarfs [sic]. Yes, we should all remember Grace better.) (MC, has this demonstrated your original point dramatically enough yet?? )
A similar approach to human-scale units is the attoparsec (and its associated measure, attoparsecs per microfortnight).
Note that the latter metric is also very close to a nanocentury / pi.
I first found a couple of these when, in disgust, I first looked at studying Corb's Modulor system, which purported to define architectural proportions in human scale - if the humans involved are dyspeptic inmates of an orphanage for dwarfs [sic].
Yes, we should all remember Grace better.)
(MC, has this demonstrated your original point dramatically enough yet?? )
I measure time taken in business meetings in nanoyawns ( 1 yawn = 31.796 years).
Back to the topic, kind/ sorta:
The late great model railroad track planner John Armstrong (among his numerous other skills) devised a system of measurement that he designated as "squares". A "square" has sides which have a length = radius of a curve plus (2 time the minimum track center). As he said, it's a real quick and easy way to determine what'll fit, and most other dimensions of a model railroad can be related to it - e.g., a 180 deg. curve will be 2 squares 'across' and 1 square 'deep', a turntable takes up about 1-1/4 squares IIRC, etc.
RME . . . Yes, we should all remember Grace better.
Concur. From a Google Search - "Grace Hopper/Quotes":
Next!
IslandManPersonally I use light-nanoseconds for measuring things. 1 foot = distance light travels in 1.0167033621639674471063578257196 nanoseconds. (With thanks to the late Admiral Grace Hopper)
mudchicken PDN: I got it. Made perfect sense here. Why TDM wanted to convert to some little used, totally off the wall convention was strange. ( Guess his car speedometer is gradated in some weird nomograph like furlongs per fortnight? We could all start speaking FRA213 language and lose most of the readers.) Almost sounds like another modeller trying to act like a railroader and he ain't got a clue
PDN: I got it. Made perfect sense here. Why TDM wanted to convert to some little used, totally off the wall convention was strange. ( Guess his car speedometer is gradated in some weird nomograph like furlongs per fortnight? We could all start speaking FRA213 language and lose most of the readers.)
Almost sounds like another modeller trying to act like a railroader and he ain't got a clue
Oh, good grief - I was trying to make this easier to understand, not harder - although for the local coordinate system, I could have used the X direction as across the track instead of along it. Let me try again:
. . . deflection/ displacement (i.e., in the vertical and lateral [across the track] directions at the joint, . . . [with the understanding that the longitudinal direction is the direction in which the track is aligned, and likely will not move in that direction]
Otherwise, some of us here with a surveying background (mudchicken comes to mind) are most accustomed to using North, East, and elevation conventions.
Try a search of "Denavit-Hartenberg Parameters", which is a system for specifying the sequence of link-local Cartesian frames associated with a robot or a CNC machine. The local z-axis is always parallel to the joint axis, same as the "spindle" for the last rotating joint on a milling machine. The x-axis is always parallel to the common normal to the pair of joint axis lines. The common normal is a unique line, that is, unless the joints are parallel. The y-axis is "just along for the ride", defined by the Right Hand Rule for axes in the sequence z-x-y or x-y-z.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
Against stupidity the gods themselves contend in vain.
Fortunately there are things like Wikipedia articles that can disprove stupid allegations -- except, I suppose, wilfully stupid ones.
While we are on the subject of international 'conventtions', I am unable to find a spindle-axis reference in either WGS84 or DIN 9300, or, say, in IERS note 36 4.2.6 regarding ITRF conventions. Mr. midget needs to send some authoritative-sounding e-mail to the appropriate standards bodies quick to set 'em straight!
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