Talk:Metric system/Archive I

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How can this article be expanded? What isn't covered by the SI article? In other words, what precisely are the differences between the two? I'd say this article should focus on that. And shouldn't the SI-link be presented a little more prominent? I've expanded it for that purpose, but that's not what I mean. Now it looks like it's just one of the many things it might mean, when it's really the most prominent one. Right? Also, I understand that the two are not synonyms, but that the SI system is a subset of the metric system. Or are there also SI units that are not metric units, in which case the two merely overlap? DirkvdM 08:39, 13 August 2005 (UTC)

I've expanded it. How? By merging what was the Metric system section of Units of measurement. The overlap with SI will have to be dealt with. Jimp 25Sep05
By this, IMVHO, you bloated the article and made it (too) SI-centric. The sections “The metre”, “The kilogram” and “The litre” should be removed, because the information therein is already present in the respective articles where it belongs. This pretty much applies to “Metric prefixes” and “The International System of Units” as well.
Note that the original French system was not a CGS system like the current text implies, instead it somewhat continued the tradition of having separate base units for geometrically related dimensions, i.e. metre for lengths, are for areas, stere for volumes and dry capacities and litre for liquid capacities; it also included only few prefixes. It’s debatable whether mesures usuelles (or metrified English unit) is a (true) metric system, too. Christoph Päper 14:53, 25 September 2005 (UTC)
I absolutely agree that the article should not be overly SI-centric. That's what we've got the SI article for. Also I don't want to have all this duplication of material either. I'll look into seeing what we can trim out of here. Jimp 28Sep05
Your comments here on the Talk page are more informative than the text of the article. I'm sure you won't mind, Crissov, if I use them in the article. Jimp 30Sep05

The article says that the metre is a certain fraction of the velocity of light, which makes no sense because the metre is a unit of length, not velocity.

Should there not be more attention for the Dutch Metric System, after all it used the same units, but totally different names?ThW5 13:59, 2 May 2006 (UTC)

i think this article should explain advantages and disadvantages for the metric system.

Overlap with SI

1. SI#History
2. SI#Cultural issues and
3. SI#Spelling variations

are all applicable to the metric system whilst

4. Metric system#The International System of Units

is best suited to SI. I suggest that 1, 2 & 3 be moved to Metric system and 4 be moved to SI. Jimp 28Sep05

There are, at least in History, some things that should remain in the SI article. Maybe split with most everything from 1960 on in the SI article (including, for example, developments related to non-SI liter), and a short paragraph there summarizing some of the earlier history (that the metric system was developed in thethe mkdesr;hISD is for fages du u tard

aware of the division of the history.

The physicist/engineer (and ordinary people also in the practical engineering camp) "cultural issues" are very much tied to SI (and, of course, the metric system in general and cgs in particular). Some about spelling variations should be in both. Gene Nygaard 11:55, 28 September 2005 (UTC)

I have merged Metric system#The International System of Units to SI#History however what remains is to merge part of SI#History to Metric system#History (I'm changing the section name from Origins of the metric system). Also I've removed the following as it s covered elsewhere on SI, Imperial unit & US customary units. Jimp 30Sep05

Cultural issues are tied to SI, you say, Gene, but go on to say that they are tied to the metric system in general also. What I'm saying is that because these issues are general-metric-system issues they should be here. The physicist/engineer bit is about cgs vs SI, right? This a a metric issue. What is metric-system-in-general should be here (this includes spelling too) and what is specific to SI should be there. Of course, this shouldn't be stark black and white: there must be some grey areas of overlap. Jimp 3Oct05

I've brought the Spelling variations section here however, I'll leave a summary at SI#SI writing style. Jimp 5Oct05

Some traditional units of measure such as the Imperial units and the U.S. customary units are now defined as fractions of SI units.

The SI includes two classes of units which are defined and agreed upon internationally. The first of these classes are the seven SI base units for length, mass, time, temperature, electric current, luminous intensity and amount of substance. The second of these are the SI derived units. These derived units are defined in terms of the seven base units. All other quantities (e.g. work, force, power) are expressed in terms of SI derived units.

I've sorted the two History sections into Metric system vs. SI links remain between the two. Jimp 30Sep05

Goals of Metric System

First of all, my apologies since this, being my first post, probably is messing with proper etiquette. Consequently, I am also reluctant to directly edit the article, any help in this regard will appreciated (besides, my English sometimes fails me, not being my native language).

I feel that the first paragraph about the metric system is somehow failing to describe the purpose of the system.

I would first state that 'metric system' simply means 'measuring system' but that since the more prominent and popular unit is the 'metre', its name got to span the whole system.

There were two main purposes for the metric system:

  1. Establish a common, universal and neutral system of measures
  2. Develop the procedures under which any laboratory provided with the right technology could reproduce the base units

Regarding the first goal, the idea was to unify the very unmanageable systems of measures then in use. Each country, town and even two markets within a large city might have different units of measure. Also, different guilds had different measures and a lot of them had the same name. Nowadays we still have two different 'gallons' on each side of the pond.

It was meant to be neutral and universal in that it would not rely on the length, width or girth of any body parts of a particular ruler, as was the norm in those days, which would make the new system hard to digest to other countries. Of course, this part still became hard to digest with some monarchies of the time and so we still have an Imperial System.

In this regard, it would be important to correct the popular misconception that the metric system was a crazy thing the French came up, just like the revolutionary calendar. Though the French were, indeed, the designers, their purpose was not nationalistic at all and the metre should not be associated with Brumaire and Floreal. Indeed, they learned from the calendar which failed to be universal because it set the revolution as its starting date and the names were related to local events, such as Brumaire which comes from 'foggy', a weather condition that though widespread, does not occurr everywhere in France itself. The metric system avoided this local or nationalistic bias.

The second goal is even more important and the most significant breakthrough in the whole system. The idea that the designers of the system would not simply craft an arbitrary measuring ruler, a hollow container and a weight and say 'this are the units, come and copy them', but that they would develop a procedure for reproducing them just from the description of the units, without any need to actually carry the physical embodiments of standards around.

As you see, neither the decimalization nor the use of common prefixes for multiples were on the top of the list of goals of the metric system, though they were also very significant concepts. To offer a counter-example, Britain decimalized its currency without changing the value of the base unit which was as arbitrary as it was before (arbitrary in the sense of not related to the properties of any physical object).

A minor goal was that the base units should be handy, literally, that you could actually show them with your hands. I wonder why they failed so badly with the 'gram', which is so tiny as to be useless except in chemistry.

The article fails to mention this procedures which, otherwise, would make the whole system look quite arbitrary.

As said, the designers decided that the units would be derived from the properties of natural objects accessible to everyone, everywhere. Thus, the metre would be a fraction of a meridian of the Earth. This was no new concept at all, the nautical mile is the length of a minute of longitude over the Equator.

The meter is one thousandth of a second of a decimal arc of the Earth measured from either Pole to the Equator. A decimal arc is also a unit of the metric system (originally called 'gon', the Greek for angle) so that a right angle is composed not of ninety degrees but of a hundred 'gons'. A hundred decimal minutes make a decimal degree, and a hundred decimal seconds make a decimal minute, so, a meter is one ten millionth of the distance from any Pole to the Equator which makes the circumference of the Earth of about 40,000 kilometers (at the time it was, by definition, 'exactly' 40,000 kilometers, later measures proved it inexact).

In using a fraction of latitude from any Pole to the Equator, instead of a fraction of longitude over the Equator, as used in the nautical mile, they carried with the 'universality' of the procedure. All countries have access to a chunk of a meridian, few countries have a piece of the Equator.

The goal of making them 'handy' shows in the selection of which fraction of the Earth circumference was used to define the metre. Using the whole circumference would have made the metre four times as long. Likewise, using a millionth instead of a ten millionth would have made it ten times larger, neither of them handy. Basically, they meant the metre to be just about 'this' size (please make proper gesture with your hands).

To get the metre as fit to its definition as possible, they had to measure the circumference of the Earth which was not a practical thing to do, so they went for the next best, measure as long a fraction of a meridian as they could possibly span. They set upon the arc in between Barcelona and Dunkirk, being the longest meridian in western Europe wholly on land and, except of a small section on Spanish territory, most under territory they had access assured. The process lasted several decades and even though in some of those years there were hostilities in between Spain and France, the measuring kept going, the French scientists safely escorted by Spanish troops while in Spain.

The unit of weight was defined as the weight of a cube of water of a certain size. A cube of water a metre on a side weights a metric ton, a ton being the informal name for a million grams. In this, the designers of the system failed the 'handiness' rule because the gram is so small that it is not practical for everyday use. The kilogram is used instead, most often referred to the 'kilo', which is not a unit but the prefix for 'a thousand'.

A cube a metre on a side contains a thousand litres, thus a litre holds a kilogram of water.

So, as you see, anyone with these descriptions, access to proper instruments, who can measure the circumference of the Earth and could distill water could make their own copies of the base units.

As time passed and the instruments improved, it was found that the Earth was not 40 thousand kilometres in diameter so that either the metre had to be redefined or the linkage in between one and the other broken. The first option was out of the question, the precision of the instruments that detected the discrepancy had already spread to the then blossoming mechanical industry and changing the metre at that point would render whole batches of incompatible nuts and bolts. At the time 'screwing', as the standardizing of screws was called, was being regarded as an important stepping stone into the progress of mechanical devices and changing the metre would screw it all up, if I may be allowed a pun.

Thus, for a period, the metre was defined as the length of a ruler stored in Sevres, France. Later on, new and more precise universal means of producing a metre were developed, namely, a certain number of wavelengths of the spectrum of a known and stable natural element. At the time this was hailed as a very important development, forgetting that the original designers meant from the very beginning that the units should be derived from the properties of natural objects.

It was at the time of this interregnum, when no property of any natural object defined the base units, that several countries, unwilling to recognize their measuring system subservient to a piece of metal resting somewhere in France, that they started defining their own systems, conveniently compatible with the French metre. In this regard, I would leave the mention of the CGS, MKS and MTS systems to a rather obscure corner of history, where they belong.

The prefix system didn't encompass all the sizes we use nowadays. Kilo and mili were about as big and as small a multiple as they could figure of any practical use in those days. The concept, though, has been successfully extended to a then unconceivable degree from nanoseconds to gigabytes.

Decimalization has gone beyond the metric system to currencies and in a confusing way, to computer memory. A kilobyte sometimes is 1024 bytes, sometimes it is a thousand bytes, a proper kilo. The small difference in between the two makes the error acceptable.

One missing and very important unit which was not part of the system was the metric day. A day would have been divided into 10 hours each with a hundred minutes in each hour, a difference not really meaningful in that mainly rural society. Actually, the decimal day had been part of the reform of the calendar, which was prior to the development of the metric system, and by the time this was occurring the revolutionary calendar was already falling in disuse and finally abolished and the decimal day with it.

The 'gon' still exists nowadays, called the 'grade' which shows up in most scientific calculators though nobody uses it, 'radians' being far more practical for scientific calculations.


--DevaSatyam 14:18, 11 October 2005 (UTC)

You haven't really messed with the etiquette, don't worry about that. It is usual to put newer categories at the bottom of talk pages however on a page as short as this (as yet) it's hardly an issue. Please, feel free to edit the article, though I would like to make a suggestion first. Now you might have already read through them but, if not, do have a brouse of the related pages, e.g. SI, metre, kilogram, litre, etc. In this way you'll be aware of whether you risk too much duplication of information.
I'm not so sure what you mean when you say "that 'metric system' simply means 'measuring system' but that since the more prominent and popular unit is the 'metre', its name got to span the whole system." The term "metric system" certainly means a lot more than "measuring system": it refers to a specific measuring system (or set of related such systems). Let us not confuse the etymology of the term with its meaning.
You write "the idea was to unify the very unmanageable systems of measures then in use." As I see it, it would be more correct to say "the idea was to replace the very disparate and unmanageable systems of measures then in use with a unified system."
I don't agree with your treatment of the MKS, CGS and MTS systems. It is my understanding that the impetus for the development of these variations on the metric system had more to do with application than any unwillingnes "to recognize their measuring system subservient to a piece of metal resting somewhere in France," CGS was useful in the physics lab whilst MTS was useful in industry. As for MKS, well this being the basis of SI, it is anything but historically obscure.
It seems that you've got a good few interesting facts about the metric system that would be worth adding. Please do so.
Jimp 12Oct05
So I did, and I hope I got it right. There were some changes made to the page while I was editing mine but Wikipedia warned me about them and I hope I managed to include them right.
I would appreciate any corrections to my English besides, of course, any to the contents itself.
My main purpose was to point out the idea of universality of the system, leaving the decimal aspect of it to a second level since, after all, decimalisation explains the relation amongst derived and base units, but not the units themselves.
I also mentioned the very pratical economical reasons for adopting a unified system, otherwise it seems a that a group of mathematicians got together and defined a decimal system of measurement just for the fun of it. Actually, I would like to stress this even further. Most people this days, even those using non-metric systems, think it is just a mater of using pounds or kilograms, yards or metres, mostly unaware of the absolute chaos of those days. Even today we still have different gallons on each side of the pond. Multiply that by a thousand such cases and you might still be short of the chaos of those days.
And I had to add the gon since the metre derives from it and the circumference of the Earth, and that is the start of all the chain of units.
I expanded the list of base units in the introduction because the metric system did, indeed, define more than just two units. The whole system was composed not only of the two prototypes for the metre and the kilogram but also of the procedures to derive these from natural properties and then each additional base unit from these two prototypes. Notice, for example, the importance of the gon as the basis to define the metre though the gon itself does not require a prototype being a magnitude without physical units so that it only requires a definition but not a prototype.
The original designers differentiated the litre as a measure of capacity from the stere or cubic metre as the measure of volume and so I changed capacity for volume in the introduction. Though a stere is exactly a kilolitre it would seem that they meant the litre to measure liquids, grains or other shapeless objects while the stere was for solids.
I also used 'natural philosophers' instead of 'scientists' since the later term didn't exist in those days
And, since I live in Europe, actually relatively close to Barcelona and the Montjuic, the southern end of the arc used to measure the size of the Earth, as per Wikipedia style rules I followed the British spelling as far as I could, though I learned American English and my spell checker is set to U.S. English and kept complaining about standardiSation and coloUr and all that. Of course the article was already localised in British English with metre, litre and so on, but I am sure some other British spelling escaped me and my spell checker.
DevaSatyam 23:45, 12 October 2005 (UTC)

National

"exclusive national standard" -What nation is this refering to? If you are still talking about France then you need to name it again because its a new paragraph. Alternatively, just append this sentence long paragraph to the previous one.

This sentence was added by User:Arfon as part of what could best be described as an edit intended to give the article an antimetric slant. It doesn't seem that he was refering only to France but to all metricated countries. As to this "measures of tyranny": I'd like to see some evidence that what he wrote is in fact the case. Until a reliable source is produced I suggest this sentence be not included in the article.
Later: OK I've done some rooting around & it seems that "measures of tyranny" is from George Orwell maybe. If so, then it belongs at Metrication arguments and counter-arguments#Cultural references.Jimp 6Nov05

The kilogram

Arfon had also added the following paragraph.

The kilogram, for the past 106 years, remains formally anchored to a single precious 
platinum-iridium cylinder in Sèvres, France but using a mass standard to calibrate other mass 
standards has its disadvantages. So, it too is about to be changed. Le Gran K, as the kilogram 
standard is sometimes called, is pretty imprecise, when compared to other standards. It could 
potentially be damaged or even destroyed and its mass changes slightly with stray dust 
particles and when it is cleaned. And it is available in only one laboratory. For some time, 
scientists have considered replacing the kilogram mass standard with a natural constant. 
Scientists at the US National Institute of Standards and Technology are exploring two possible 
ways of replacing the kilogram mass standard. Both methods would base the kilogram on the 
Avogadro constant, which is defined as the number of atoms in 12 grams of pure carbon-12. One 
method would directly determine Avogadro's number based in part on X-ray measurements in near 
perfect silicon crystals. Another method would determine Avogadro's number based in part on 
electrical measurements in a watt-balance experiment.

Arfon claimed that it is about to be changed. The fact is that this has not yet been decided. It may be changed. The paragraph has since evolved to the following.

Since 1899, the kilogram has been formally anchored to a single platinum-iridium cylinder 
in Sèvres, France. However, this is an imprecise mass standard as it could potentially be 
damaged or even destroyed, and because its mass changes slightly with stray dust particles and 
when it is cleaned. Furthermore, it is only available in one laboratory. Scientists at the US 
National Institute of Standards and Technology are exploring two possible ways of replacing 
the kilogram mass standard, both of which would base the measurement on Avogadro's number. 
One method would directly determine Avogadro's number based in part on X-ray measurements in 
near perfect silicon crystals; the other would determine Avogadro's number based in part on 
electrical measurements in a watt-balance experiment.

The kilogram is precise. The kilogram is defined to be precisely the mass of what our Arfon calls Le Gran K. The potential for loss or destruction is a problem but it doesn't entail imprecision. Nor does the variation in its mass entail imprecision though this too is a problem. It does vary in mass but because of dust and cleaning? Where did he get this info? They keep it in a sealed container (though it is cleaned). The cause of the variation is unknown. Yes, there is only one but there also are national copies. It's by comparison with the copies that the variation in mass is known. There are more than two alternatives under consideration and the US NIST is not the only organisation doing the investigation. This is all covered in great detail where this detail belongs: at the Kilogram article. All that is need here is a breif mention of the main points. This is what I'm about to do. Jimp 9Nov05

A few minor edits as of Jan 2006

The article had read as follows

As the result of scientific progress, refinements, and different choices ...
The modern metric system ... is called the International System of Units (SI) ...
or, simply, "Standard". It is called "Metric" predominantly in places where it is
not the main system, such as in the USA.

I've removed the following.

or, simply, "Standard". It is called "Metric" predominantly in places where it is
not the main system, such as in the USA.

I've never heard SI refered to as Standard. I have, though, heard it refered to as the metric system and have never lived in the USA. I don't believe that the general public knows about the metric-SI distinction nor do I believe that most of them would care. Even in metricated countries (like my own) the distinction is not one that normally needs be made thus the terms will be used interchangeably. I'd say the term metric will be favoured because it sounds less technical.

The article also read as follows.

The acceptance of the system in revolutionary France was not particularly great.
... Napoleon, ... authorized the usage of Mesures usuelles,
ancient measures defined ... this law was canceled ...

I've changed it to the following.

The acceptance of the system in revolutionary France was not particularly great.
... Napoleon, ... authorised the usage of Mesures usuelles,
the traditional French measures redifined ... this law was cancelled ...

Two points: spelling and nonsense. In keeping with the rest of the article I've replaced the US spellings with Commonwealth ones as per Wikipedia Manual of Style. Secondly, and more importantly, Mesures usuelles is based on the traditional French system. It is not untrue that it is therefore based on ancient measures but this is very indirect. It is misleading to simply say that Mesures usuelles is based on ancient measures.

I've also removed the following.

and non-metric system systems of measurement are now only used in
the United States, Liberia and Myanmar (Burma).

It is not true. Things are not so black-and-white. Distances on UK roads are still marked in miles and beer in UK pubs is still sold in pints. In Australian pubs beer is sold in volumes which are based on the Imperial fluid ounce simply rounded to the nearest 5 ml. In Japan floor sizes are quoted in tsubo by real estate agents. Canadians often use Imperial units. Liberia and Burma, on the other hand, whilst not officially metricated are likely to have adopted the system as well as most other nations in their regions ... but I'm only guessing here. Jimp 02:10, 27 January 2006 (UTC)

NPOV in history? "Apathy"

This article attributes the fact that the US and the UK haven't fully switched over to the metric system to general public apathy. This is not a fair, objective statement to make.

mickey 02:06, 29 March 2006 (UTC)

Nonsense- the apathy is rooted in the effort required to change everyday life to something that is uncustomary, alien, less useful day-to-day and downright unfamiliar; Then add in the infrastructural cost across the largest most industrialized nation, and don't look for the USA to metricfy until all that plant and equipment becomes obsolete and in need of replacement. I remember as a boy in the 70's how we would be switched over in the next fifteen years. Ain't gonna happen. The inertia is too great. When will it occur? Sometime after most all new cookbooks are written to present recipees in metric units instead of customary units... Have you seen the first of these released yet? Neither have I. FrankB 18:41, 31 March 2006 (UTC)

Merge with SI?

Seems to me there's too much overlap and not really enough reason to separate Metric system from SI. I think we should probably merge the two articles. What do others think? ProhibitOnions 18:48, 30 March 2006 (UTC)

  • Strong Keep Both, the SI article should be about the evolved current standards, not the generalized conceptualized idea of a metric system. Both get referred to in many links in other articles on measurement in general, and the distiction is necessary to preserve the sense of those links. FrankB 18:57, 31 March 2006 (UTC)
  • Keep both. There's no good reason to clutter the SI article up with all the historical stuff and the various other metric systems that have been used throughout history. Gene Nygaard 01:16, 4 April 2006 (UTC)
  • Strong Keep Both: There are a number of variations on the metric system. To lump them all at SI would make absolutely no sense whatsoever because not all of them are SI. So the question is not whether there is "enough reason to separate Metric system from SI" but whether there is enough reason to separate SI from Metric system. To lump them all together, as Gene points out, would cause too much clutter, wherever they be lumped. It would also further obscure the distinction between what the terms the metric system and SI mean. They are not the same: one is a varient of the other. Jimp 08:54, 13 April 2006 (UTC)