Metrication matters - Number 97 - 2011-06-10
Dear Friend of metrication,
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2 Feedback - notes and comments from readers
3 Oddities - measurements from around the world
4 Tips - pointers and methods to make your measurements easier.
5 Signs of the times
7 Q&A - readers' questions and answers
8 Rule of thumb
10 Hidden metric
It is interesting to watch some individuals, groups, companies, industries, and even whole nations as they struggle to achieve that which is both simple and inevitable. You have to wonder why. One reason for the struggle is the choice of metric conversion as the preferred process to use for their metrication upgrade process.
With hindsight and a little historical research, it is easy to see that metric conversion has never worked as part of a metric transition.
Metric conversion has never produced a smooth metrication transition in the past, it is not producing any meaningful results at present, and it is reasonable to suppose that metric conversion will not be successful at any time in the future.
To try to understand why this is so, it seems to me that when people approach a metrication transition for a single measuring word there are two main routes that they might take.
Method one — and apparently the most obvious to many people — is to take the current measuring word, do a metric conversion, and settle on this metric value, or a nearby rounded value, as the new standard.
A second way is to consider the old value within the environment that it will be used in the future, consider the people who will actually use this value most on a day to day basis, then to choose an appropriate value — most likely in whole numbers — that can and will be suitable for a fast, smooth, and complete metrication upgrade program. To use this second method you need to know a little about metrology and a lot more about metrication. Let me give you an example:
Consider the tablespoon.
Choose the old value that a tablespoon is half a fluid ounce. Look up a metric conversion table — 1 US fluid ounce = 29.5735296 millilitres (source Google) — apply the conversion 14.7867648. Then decide on a suitable rounding. In this case let 14.7867648 become 15 millilitres.
Taking no notice of other calculations done for pounds, dry ounces, and pints, teaspoons, or cups, promulgate your decision to cooking teachers, recipe book writers etc. as the "new" standard. Your audience, as professional measurers of many hundreds of measurements every day, immediately knows that the "new" 15 millilitres is, in fact, still an old half ounce and they will fight like fury maintaining that the change is not necessary in their kitchens. They will not see a need to change their (100s of) recipe books, all their spoons and, if they are recipe writers, they will have no reason to change to metric system units when devising new recipes for such things as their magazine columns. Method one can delay any transition indefinitely — at least for a few hundred years.
Look at the old practice and note that there are many different size tablespoons in domestic and commercial kitchen drawers. Note also that sets of measuring spoons vary according to the maker's idea of a standard set of spoons. There is an opportunity here to do some standardisation.
Measure a range of these tablespoons and note that they generally vary from about 12 millilitres to about 22 millilitres, with a median point somewhere about 18 millilitres.
Consider that the tablespoon question is only part of a wider consideration where, in Australia:
- Nominal pounds will change from 454 grams to 500 grams (up about 10 %)
- Nominal pints will change from 568 millilitres to 600 millilitres (up about 6 %)
- Nominal cups will change from 227.304 millilitres (8 fluid ounces UK) to 250 millilitres (up about 10 %)
In this context it would is reasonable to increase tablespoons from about 18 millilitres to 20 millilitres (up about 11 %)
- Consider that the "new" value can be readily divided in a busy kitchen to half tablespoons (10 millilitres) and quarter tablespoons (5 millilitres). (Note that 5 millilitres will be the new metric value for a teaspoon.)
- Consider, also, that there is now no obvious connection to the old half fluid ounce.
Method 1 is the approach taken for tablespoons in the UK and in the USA. This approach is continuing with absolutely no indication of success anytime within the next 100 years or so.
Method 2 is the approach taken in Australia, New Zealand, and South Africa. The metrication upgrade was completed with about 5 years from 1975 to 1980.
I consider Method 2 to be the better way.
There are a lot of people who are seeking and providing metric conversion services to start people on Method 1. I just looked up "metric conversion" on Google and there were 1 270 000 results. That suggests that there is a lot of totally pointless "metric conversion" activity going on in the world.
Sadly, I think that the "metric conversion" seekers will all be disappointed with the results as they were more than likely seeking a smooth, economical, and FAST upgrade to their full use of the metric system. They simply chose the wrong approach; metric conversion is not the way to go.
2 Feedback - notes and comments from readers
A proponent of the metric system (name withheld) wrote to me with an analysis of the ways that the anti-metric people in his workplace seem to behave toward him. He wrote:
Opponents of a change to the metric system are a predictable lot who employ simple methods for their opposition. Basically they have four methods:
- Do nothing
- Deny that a change is necessary
- Admit that a change is necessary but make up excuses: "now is not the right time"; "it will cost too much"; "we need more study"; "make up complex words and promote them"; and so on ...
- Discredit the proposer of the change by personal attack.
This struck me as a sort of paraphrase of the work of the organisational change professor from Harvard, John Kotter, who expressed very similar ideas in his book, "Buy-in". See http://www.kotterinternational.com/BooksAndResources/Books.aspx
3 Oddities - measurements from around the world
Small groups of people invariably choose to speak in jargon once they have been working together for a while. Often this becomes undecipherable when they use this jargon outside their own small community. As an example, astronomers often use jargon words such as astronomical units, light years, and parsecs often with very loose definitions of these terms — if there are any fixed definitions at all. You will be pleased to know that astronomy jargon also runs to the "saros" that can be used to describe a period of time. A saros is approximately 18 years, 11 days, and 8 hours.
It is very hard for users of jargon to upgrade to the better honesty, better simplicity, better accuracy, and better precision of the metric system because they are using measuring words for social purposes such as decisions on who can enter into their "astronomy club" and who can occupy the various hierarchical positions among the "astronomy club" members.
Amateur sailors, with fathoms, nautical miles, and knots, and horsey people, with hands for horses, have similar jargon loaded impediments to fully upgrading to the better honesty, better simplicity, better accuracy, and better precision of the metric system.
4 Tips - pointers and methods to make your measurements easier
Tips for writing metric system units
- Full stops are not used after symbols. Technically, an SI symbol is a 'mathematical representation of units' and it is not a more or less randomly generated abbreviation.
- For this reason they remain the same in the plural. To write kgs instead of kg for kilograms is wrong.
- Separate the symbols from numbers by a space: 134 mm and 44 °C are correct. The old Babylonian angle measures, degrees, minutes and seconds (37° 40' 2"), are different in that they have no space between the number and the unit; but this does not mean that you write these as: thirtysevendegrees, fortyminutes, or twoseconds!
- The word per is officially preferred for such terms as kilometres per hour.
- Any unit may have its power increased by the addition of an index number, as m2 for square metre, or m3 for cubic metre.
- Do not mix units. Choose the appropriate metric system unit and write, say, 1234 mm or 1.234 m or but not 1 m 23 cm 4 mm.
5 Signs of the times
It looks like the USA is again to reconsider medical errors in hospitals. The research, "To err is human" in 1999 reported that, based on New York hospital data, 98 000 people died each year from medical errors (this figure was 44 000 if the estimate for the whole of the USA was based on Utah data).
A major source of error is that patients and hospital staff routinely talk about their patients in pounds when all medical research, drug preparation, and drug administration are all done in metric system units. They also speak about distances in inches because of the difficulty of upgrading to the metric system using centimetres.
My belief is that one unnecessary death due to error, especially a measurement error, is one too many.
Many other hospital patients did not die from the medical error but were permanently hurt and thousands of family members are still suffering from the consequences.
Randy Bancroft shared this quotation from Victor Hugo with the United States Metric Association (USMA):
An invasion of armies can be resisted, but not an idea whose time has come.
7 Q&A - readers' questions and answers
What was the system of measurement before the metric system?
There was no system of measurement before the metric system.
When Bishop Wilkins invented the "universal measure", this was the first system of measurement ever. Wilkins "universal measure" was the system that developed into the "decimal metric system".
However, while the metric system was evolving into the 'International System of Units', many efforts were made to try to retrofit properties of the metric system on to older collections of measuring words and measuring methods. Several things should be noted about these old modified methods.
It is not correct to say that these old modified methods were 'systems', even though they are often called by that name. They are not 'systems' mostly because they are not complete methods of measures. For example, while mechanical engineers were devising their own 'system' they gave little thought to any issues faced by aeronautical or civil engineers. As a result, in any 'Gravitational System', there are aeronautical engineering, civil engineering, and mechanical engineering versions, and each of these has a distinct variety for the UK and another for the USA. And none of these 'systems' has anything to say about chemistry, medicine, nutrition, or any other of the remaining thousands of human activities.
These methods are unsupported by any international (or national) organisation, so there is very little information about what these old 'systems' actually are. These 'systems' are not documented, so it is quite difficult to find details about these old measuring methods. This can be a real problem if you are trying to cite a 'standard' that was used for a particular set of measures – often no such 'standard' exists. If there is no standard document that you can use as a reference to define the system – and the way it was used – then you can only vaguely say that they used 'inch-pound units' or they used 'foot-pound units'. You might find some documentation for the Absolute Units and for Engineering Units, although this can often be contradictory. For example, British Absolute Units, used mostly by physicists, had the pound as a unit of mass and the poundal as a unit of force, while British (and USA) Gravitational Units, used by engineers, employed a pound for force and a pound for mass. Naturally, the scientists and the engineers used different length units for their work. Even in engineering, aeronautical engineers used the pound for force and the slug for mass while mechanical engineers a pound for force and a pound for mass. When civil engineers used a foot as their unit of length, mechanical engineers used an inch as their unit of length. Over time, the different measuring methods became many measuring 'systems'.
Leaving aside the question of how you measure something as basic as length (you could choose to use international, nautical, statute or survey methods), there is also the question of which length units you will use (thous, inches, links, feet, yards, rods, poles, perches, chains, miles, or leagues) when you decide on a measuring 'system'. There is no 'system' between these odd, historically generated, measuring words.
They are also not 'systems' because no attempt was ever made to form them into coherent measuring methods like the coherence of the metric systems. Overall, it is best never to use the word 'system' with old units. If you are examining an old measuring method where the inch and the pound are the dominant units, then say that it uses inch-pound units and ignore the other units in the set. If you are examining historical documents where the foot and the pound are the dominant units, then say that it uses foot-pound units and ignore the others.
Names of old measuring methods that you might find include: Apothecaries Units, Avoirdupois Units, British Absolute Units, British Engineering Units, British Gravitational Units, English Engineering Units, Foot-Pound Units, Foot-Pound-Second Units, Foot-Pound-Second Units, Imperial Units, Inch-Pound Units, Inch-Pound-Second Units, Troy Units, and USA Customary Units. Don't forget that many of these sets of units might appear in UK and USA versions of aeronautical, civil, and mechanical engineering, as well as in surveying 'systems'. Note, too, that a lot of these use the word, unit, when they mean unit to mean "measuring word" as the "units" has no fixed and defined meanings.
8 Rule of thumb
If the Earth was valued at $1 000 000.00 the atmosphere would be valued at $1.00 when you consider that the proportion of the whole Earth to its atmosphere is roughly 1 000 000 to 1.
- The mass of the atmosphere is about 5 teratonnes (= 5.1480 x 10^18 kilograms).
- The mass of the Earth is about 6 zettatonnes (= 5.9742 × 10^24 kilograms).
As noted previously, the only measurement 'system' ever developed, in the world, at any time, was the metric system, now known as 'The International System of Units (SI)'. It took about 170 years (1790 to 1960) for the first metric system to evolve into the International System of Units – the modern metric system. During that time, the metric system took several forms, and these can, in hindsight, be thought of as evolutionary stages, as each of these metric systems were improvements on previous metric systems.
The initial idea for a "universal measure" came from Bishop John Wilkins in 1668.
The "decimal metric system" was developed and organised in France, by an international committee, during the 1780s and early 1790s. The "decimal" part was from the USA, the word, "metric" was from an Italian translation of Wilkins words, "universal measure" into Italian and the "system" was from Bishop Wilkins original idea.
The "decimal metric system" was legalised in France in 1795.
The first major suggestion for improvement came from Karl Frederick Gauss who proposed that new electric units should be based on the millimetre, the milligram and the second in 1832.
In 1873, the British Association for the Advancement of Science (BAAS) also realised that new units were needed to measure electrical properties. They proposed new electrical units based on the centimetre, the gram and the second. Historically, this became the cgs system when the first Congrès International d'Electricité formally adopted this system in 1881.
By the end of the eighteenth century, divisions had developed between scientists and engineers. Scientists, such as chemists, were quite comfortable using centimetres and grams, but the engineers wanted to use much larger units such as kilograms or tonnes. One particular area of difference involved electromagnetic units (emu), based on the cgs system, which were opposed to the electrostatic units, also based on the cgs system, and both of these were opposed to the international electrical units that are based on the mks system.
Giovanni Giorgi, an Italian engineer, proposed a compromise in 1901. Giorgi's system was based on the metre, the kilogram and the second and he suggested that an electrical unit would need to be chosen to construct a fully coherent system of units. In the meantime, engineers in France were using – and lobbied for appropriate laws – a system based on the metre, the tonne, and the second. The mts system could be used legally in France from 1919 to 1961. Engineers, all around the world, also devised another metric system based on the metre, the kilogram (of force not mass), and the second. From these competing systems, the Commission Electrotechnique Internationale adopted the Giorgi system, in 1935.
Subsequently, in 1948, The Giorgi system was also adopted by the Conférence Générale des Poids et Mesure (CGPM) and the ampére was selected in 1950 as the electrical unit. This system was known as the mksA system.
Considerable work followed to further develop the mksA system until 1960, when, with the addition of several other new units, the modern metric system was named the 'Système International d'Unités' or, in English, the 'International System of Units'. The modern metric system is officially designated, and it is known in all nations, and in all languages, by the initials, 'SI', pronounced 'ess-eye'.
10 Hidden metric
Rumor has it that some of the road engineers in the UK are placing the mile signs next to the 1600 metre markers because this is easier to do rather than placing mile markers at 1609.344 metres. A political directive of Maggie Thatcher's in 1989 requires that the roads are marked in miles but the engineers design and build the roads in millimetres, metres, and kilometres.
Pat Naughtin is a writer, speaker, editor, and publisher. Pat has written several books and has edited and published many others. For example, Pat has written a chapter of a chemical engineering Encyclopedia, and recently he edited the measurement section for the Australian Government 'Style manual: for writers, editors and printers'. Pat has been recognised by the United States Metric Association as a Lifetime Certified Advanced Metrication Specialist.
Pat is the author of the e-book, Metrication Leaders Guide, that you can obtain from http://metricationmatters.com/MetricationLeadersGuideInfo.html
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