Trouble with the Metric System
The following is a description of a real-life, as opposed to a sterile, academic usage — or attempted usage — of the metric system to actually do something constructive. Throughout TYSK has added some comments in this color type. Also, all bold, italic, and underlining were inserting by me.
ABC (Australian Broadcasting Corporation)
Trouble with the Metric System
Host Robyn Williams and his guest Arthur Marcel, English teacher, Brisbane, on the advantages of the Imperial method of measurement compared with the metric method.
Then in 1972 (February again I think) on joining the ABC Science Unit, my first job was to produce a series of desperately cheerful and unrelentingly positive promos for metric conversion. Now 26 years on, we are used to the new units. Or are we? Here's Arthur Marcel from the University of Queensland. [Note that Mr. Williams is an academic NOT a real user of the metric system for which he lobbied.]
The contemplations were painful because I had just realised the mistake I'd made in paving the yard before I'd built the shed. The reflected radiation from the flat uniform surface and surrounding brickwork increased my sweat-soaked discomfort to the point of making it difficult to keep my eyes unblurred by the effects of wetness and glare. Still I pressed on.
I had meticulously drafted my own plans and now they were open and tacked to a board alongside my carpenter's horse. The task at hand seemed simple enough. I had to mark and cut the wood, then nail, screw and glue it all together in the right order. Moreover, each plank needed to be cut perfectly square and to an exact length. I was as much a perfectionist then as now, and this shed was to be the manifestation of an inner yearning for aesthetic purity.
As usual that day, I was engaged more in art than craft. My shed would be more than just a shed, it would be a monument and I would be its creator. It would stand as a testament to my ability as a modern human, with the aid of my newly bought and still shiny modern tools, to transform nature's rough sawn resource into an exact three-dimensional copy of the drawings. Every seam had to be parallel, every cut had to be accurately measured and precisely executed.
Now, even though I had been brought up on the Imperial method of measurement, I had calculated all the shed's measurements in millimetres and neatly labeled each dimension with a three or four digit number. [For us here in the states, a good example of this problem is a typical sheet of plywood. WE would say it is 4x8, meaning 4-foot by 8-foot. Simple. In metric notation this would be 1219.2mm by 2438.4mm. Even if rounded off to 1220 by 2440 you can begin to see the problem developing.] This was not an instinctive process but I had used my new metric measuring tape to get an idea of each dimension and then relate these dimensions to the picture of the shed I had in my head. [Ah, relationship. Notice that even a young child, if told you were busy hefting about 4-foot by 8-foot sheets of plywood all day and too tired for a walk in the park, would be able to grasp some idea of the size of the load. FEET is something we can all relate to. Even if it is doubtful anyone's feet are 12-inches long, it is a unit of scale that has some relationship to its size.]
I was quite proud of this measuring tape. Each centimetric division was neatly subdivided into two sections of five millimetres each. [Centimeters, while in common usage, are NOT officially recognized metric units.] However when I had bought this tape, I was a little annoyed to find that it was a hybrid, with the old Imperial system of feet and inches marked along the opposite edge. I had not been able to find a purely metric one. [Pity that.] I had, in fact, spoken to the store person about this deficiency. I distinctly remember my dismay upon being told that his customers still wanted both systems. I had scoffed at the idea of a lot of old fuddy duddies being unable to cope with the new and obviously better, metric system.
So away I went, enthusiasm only surpassed by my ignorance, measuring, cutting, nailing, glueing, pausing only briefly to take a swig from my jerry or to sharpen my pencil. The sawdust started to pile at my feet. Unfortunately, so did numerous badly measured and wasted offcuts.
Suffice to say that by half way through the day, faced with the distinct possibility of having to buy more wood if I continued using the metric side of the tape, I went inside and using a calculator, converted all my beloved millimetres to feet and inches. [Argh! 1 millimeter = 0.03937 inches. I'll bet this was fun. It also lends itself to numerous rounding off errors.] That moment was a turning point. By the end of the week, when the shed was almost finished, I had wasted far less wood in four-and-a-half-days than I had done on that first morning.
Yes, why? I didn't actually know why at the time. It took weeks of thinking about it before I even began to form an opinion. The conclusions I came to were twofold: firstly, there is the matter of short-term memory recall. Metric measurements are in the form of four digit numbers. These four-part 'packages' are quite complex in that they don't have a reserved slot in a simple human mind like mine. I mean I have pigeon-holes for all of the ten digits by themselves, and even up to every possible combination of two of them. However, there are 10,000 possible four-digit numbers, and for me they are just not quickly graspable. So either they had to be learnt by heart, a process which was slow and unreliable given the way an operation was continuously repeated throughout the day, or they had to be repeated over and over like a mantra while each measuring and cutting operation was performed, an equally unreliable process given the distraction factor. [Rather than think poor Artie was a bit of a dunce, try this exercise. Jake is reading the plans and giving you the dimensions so you can cut boards to length... "We need two at 1195, one at 1245 and one at 1445." You got that? Are you sure? Maybe Jake had better repeat that for you.] Writing the measurement down on an intermediate piece of paper was partly successful, however it was also slow, and I often got out of sequence. Fatigue and uncertainty was compounded by an increasing lack of confidence and the need to constantly recheck the number before putting steel to wood. [Number "packages" have long been recognized and are taken into account whenever ease of use is given consideration by those designing number usage. It is no accident that the phone company designates a number: xxx-xxx-xxxx. Or, three number packages tied together. Also, how often have you found yourself having no trouble remembering the first two 3-digit packages and then had to re-check the fourth 4-digit one? For most people, three is fine and for many, four is as well. However, any more than that is stretching usability to the limit.]
Secondly, there is the matter of the metric distance scale. The standard metric tape that a prospective genius like myself buys in a hardware shop is not very well designed. [Be glad one side had the Imperial system on it, Artie.] As I said earlier, each centimetric division on my tape was subdivided into two half centimetric divisions which were in turn divided into five millimetric divisions. [THAT is because 2 and 5 are the ONLY numbers with which the metric system, being based on the number ten, can be evenly divided.] Now that meant that there were four millimetre graduations of equal height between each centimetre graduation (these being the tallest) and each half centimetre graduation (these being the next tallest).
When trying to make an exact measurement with this kind of tape, the eye, which is after all the final arbiter of all human measuring techniques, no matter what the intermediate machine might be, has to make a logarithmic judgement as to where on this scale of up to four equally tall graduations the pencil must fall. Now with time to spare, a comfortable desk, and just one or two operations to perform, this is not such a difficult task. [For the most part, the proponents of metric usage have just that luxury. These pointed-headed elitists sit at their desk and perform a few calculations with ease and then declare the metric system superior. Note also that the width of a typical pencil lead used for marking lumber is over a millimeter in width just by itself!] However, on a hot, gusty day, with a face full of perspiration, dust, hair and glare, it becomes truly eyeboggling. The most difficult measurements are those ending in either a two or a three, or a seven or an eight. These two graduations just blurred into one after an hour or so. Now I fully admit that it was my desire for exactness that led me to such fine measurement, however I feel it is a poor compromise to round everything off to the nearest five millimetres, something that I wasn't prepared to do. [Such rounding also leads to some very interesting, cumulative errors. I know, trust me.]
With the Imperial system I didn't have these problems. Firstly, the Imperial numbers were easier to remember. This was because each Imperial measurement is separated into two packets of easily graspable, one digit numbers [feet and inches], plus a packet of 15 possible fractions. There were 15 fractions because I was working to the nearest 1/16th of an inch, this being the thickness of my saw blade and as precise as I cared to go. Although I don't recall now, the only two digit number I could ever have encountered that week would have been eleven inches. [Oops Art, you forgot ten-inches. But why quibble at this point, right? Go on, please.] What I do recall though was that not only could I consistently remember the current number but I could remember a lot of the previous ones as well, to the point of not having to refer to the plan for subsequent cuts of the same type.
Secondly, the Imperial measurement scale is eminently readable. The inches are wide enough not to be crowded out by their indicating digit and the fraction scale is totally binary, meaning that there is only one subgraduation between higher order graduations, each of these being of correspondingly shorter height. There is no counting of graduations required at all. I believe that my preference for the Imperial system was not merely a case of having gotten used to it as a child, though I may have had an advantage from my spanner days when it came to remembering those 15 fractions. I no longer believe that the continued use of Imperial by many people can be compared to, say, the survival of the QWERTY keyboard or the VHS video cassette where an inferior system prevailed simply due to earlier establishment. [It survives because it is a real form of measurement. Meaning it is based on reality and can be related to real, physical items.] Of course it must be remembered that I am only talking about analogue measurement of distance. Metric scales not only have an obvious advantage for most forms of digitally read measurement, but the system as a whole is superior when it comes to calculation, concise notation, range of application, transfer and transposition. [Phooey! See below.] Even so, I couldn't help asking myself why the need to introduce metric across the board, especially where, as I have argued, it seems inferior.
[One very important note here. This so-called ease of use for calculations or, inherent accuracy, is a total fallacy propagated by those who may on occasion do some calculations with the metric system and say, "That was easy". Calculations with feet, inches, or even miles is equally easy. Why can this be? Because every fractional division of an inch (the base unit) converts to a simple decimal number. Example: 1/4" = 0.25", 1/8" = 0.125, 1/16" = 0.0625 and so on. Further the main unit of usage, the foot, is divisible by 2, 3, 4, 6. The meter on the other hand gets messy upon the first division of parts greater than 2. Example: 1/3 foot = 4", 1/3 meter = 333.333333........ millimeters. Yuck!]
Indeed, the question becomes a broader one: What is wrong with a hybrid system, especially when there is little need for interaction between the separate parts? We already have the example of the aviation industry sticking with feet for altitude measurement, and nautical miles for navigation. [Art offers a faulty analogy here. Both FEET and MILES are Imperial units of measure. A more proper analogy is the American medical field which is rife with hybridization. Your doctor measures (5' 10") and weighs (130 lbs.) you with the Imperial (actually, American standard) system yet, prescribes medication in milligrams and milliliters.] They have done this because not only was the system up and working well with an untold number of expensive altimeters, distance gauges and charts, not to mention many expensively trained brains already ticking away in feet and miles, but also because of superior application suitability. The thousand-foot measurement is near enough to the ideal vertical traffic separation unit (it's a close as you want to go, yet gives thirty or forty easily graspable, two-digit packets of information); and the nautical mile fits precisely into the latitude/longitude positioning system of which it was born. [The nautical mile is based on the distance between degrees and minutes of longitude and latitude ... critical for proper navigation.] In the air, naturally, the wrong number can mean more than a few wasted planks of wood, so the superior system is retained. [BTW, I know you are curious but too lazy to do the math. One-thousand feet = 304,800 millimeters, or 304.8 meters. Now try to visualize that in the three-dimensional world of flight!]
The Imperial system of measurement is an evolved system, as against the metric system which can be best described as revolutionary. [Actually, created by government decree and then the subjects were forced to utilize the metric system - not without considerable grumbling I might add.] The Imperial units were derived from commonly experienced physical objects, such as the human foot and the length of an English King's arm. Appropriate subdivisions kept unit length and number within easy human range, making them so suitable for the measurement of such common objects. The metric units, however, are reductions of astronomical size quantities, using a constant subdivision factor of ten. The length of the metre, a dimension which underpins the whole metric system, was originally (and quite erroneously, as it turned out), calculated as a fraction of the Earth's diameter. Given their respective origins, it would be a very strange coincidence indeed if metric units were superior to Imperial ones for everyday domestic measurement applications. Perhaps though, the revolutionary origins of the metric system have something to do with the wishes of those who want it introduced across the board.
Perhaps an analogy with the computer industry might be illuminating. In the '80s there was a trend for big, totally integrated information systems. Many of these either failed or never got going. It is now recognised that a network of smaller, localised sub-systems, each handling their own particular area in their own particular way, is superior. Not only are they easier to implement and maintain, but each sub-system evolves to best meet the needs of its particular service sector.
Also let us not forget the aesthetic argument. Some systems have an appeal which transcends their utility. For instance, take the world's surviving languages. I have heard various estimates, but 6,000 seems to be a popular number. It is forecast that in the next 100 years only half of them will have survived the interactions of the global village. From a utilitarian point of view isn't that great! Better communication all round, less misunderstandings between people and nations, etc. Yet why are there so many language preservation societies, academic institutions and even national governments bemoaning such linguistic attrition and doing their best to preserve their respective native tongues, and why, closer to home, are Australians resisting the Americanisation of our spelling? Why do so many of us think it worth the effort to keep the 'u' in 'neighbour'?
Whenever humans attempt to interpret and manipulate reality, there will always be conflict between our need for specificity and our difficulty in sustaining complexity. I believe that not only is there nothing inherently wrong with hybrid systems, but that it is only hybrid systems which can best optimise this relationship. Hybridisation is an inalienable part of the process of natural selection, as are indeed, man's futile attempts to circumvent it. Hybridisation brings together the best and the worst traits, and time, all 24 hours per 7 days per 52 weeks per year of it, does the rest. The metric system is a wonderful invention, and will probably always have a place in this technological and increasingly computerised world. However, it isn't the universally superior measuring system it's often touted to be, especially when it comes to getting simple things like, for instance, building garden sheds, done efficiently and expeditiously. The capacity of human beings to know and use many systems simultaneously shouldn't be under-rated, for given an opportunity they will always tend to use what best fits their purpose. [Amen, brother Art.]
Arthur Marcel is a Brisbane English teacher completing a Master's Degree at the University of Queensland.
©1998 Australian Broadcasting Corporation
7 oct 1999