I was quite surprised at the substantial cost of A Brief History of the Metric System, and when it arrived, that it was only about 6 mm thick. I was unprepared for its fealty to contemporary research on the origins of the metric system. I can say, without equivocation that the discussion of the metric system—though brief (as the title states) is the most complete I have seen. Carmen J. Giunta states early in Chapter 1:
The metric system did not “evolve” from the customary weights and measures in use in late eighteenth-century France, but neither did it spring fully formed from the enlightened minds of that nation’s savants.
He hints that the history as it has been portrayed in the past has been incorrectly stated. He immediately begins to discuss John Wilkins and Christopher Wren’s musing on what the basis of a universal measurement system might consist. He mentions details of Wilkins investigation of which I was previously unaware. Wilkins discussed using the Earth as a basis for measurement, but dismissed it as impractical. Giunta traces the idea of using a seconds pendulum as a basis for length back far earlier than Wilkins, and how Jean Picard (1620-1682) suggested in 1671 that the period of the seconds pendulum might vary with latitude. He goes on to describe how there was an anemic attempt in Britain to address weights and measures with a seconds pendulum, around the time the metric system was under discussion in France, by John Riggs Miller (c. 1744-1798) which fizzled out.
Giunta’s discussion of measurement contemplation and (non adoption) in the United States contains a number of interesting historical nuggets I had not previously encountered.
For such a short monograph, Giunta has a more nuanced discussion of the creation of the metric system in France than I have encountered with other authors. He states:
Other committees constituted in 1791 included Borda and Cassini to measure the seconds pendulum;……”
Other authors generally do not discuss the elaborate seconds pendulum designed and measured by the French scientists who developed the metric system.
His discussion of the development of modern SI states:
When the SI was launched, the kilogram was the base unit of mass, defined by the international prototype kilogram of 1889. A proposal was made to change the name of kilogram since it was undesirable for one of the base units to have a prefix, but the name survived.
Long-time readers know that the use of a lower case k for kg, km, kN, etc., has always been a pet peeve of mine. Other magnifying prefixes are capitalized, Mg, Tg, GHz, why not Kg or Km?
There have been a number of proposals for base units, but this was new to me:
In Germany, the preferred set of mechanical base units was the millimeter, milligram, and second; call it mms.
In Chapter 6, his final chapter, he discusses The Metric System and the United States. He gives a good summary, but then, in my reading of history, and of John Quincy Adams’ report on measures Giunta has an incorrect interpretation of the concluding paragraph of that report. He states:
Adams was effusive in his praise of the metric system and of the basic science that came out of its invention.
Adams’ concluding statement was actually veiled snark, and certainly not a pro-metric statement given the context of his report. Adams was an Anglophile with an English wife. It becomes clear in his report that Adams is NOT pro-metric, and definitely against the new system. Others in history who read the report in the late 19th and early 20th century commented that it was anti-metric, and held back metrication in the US. They even point out that his “perfect” English system, only 3 years after his report, was reformed and replaced in the UK by the British Imperial System. We in the US still use earlier British medieval units of measure. My discussion of JQA’s report may be found here.
Giunta offers a graphic from NIST showing a metaphor of an iceberg that almost all of industry uses metric. I’ve never seen a study that can even demonstrate we are even 50% metric in the US, let alone 90%. My experience as a consulting engineer is that I have not encountered a single medium sized corporation that uses metric in the US. Certainly not aerospace, which is definitely a large corporation. If the book Flying Blind is any guide, aerospace will remain non-metric indefinitely.
Giunta finally concludes by offering his view of Why is the US Still not Predominantly Metric? He concludes, like many others, that the US government has never mandated metric for use in our economy. He is correct that it is very unlikely the US will become metric anytime soon. Perhaps in 1000 years?
If you liked this essay and wish to support the work of The Metric Maven, please visit his Patreon Page and contribute. Also purchase his books about the metric system:
The first book is titled: Our Crumbling Invisible Infrastructure. It is a succinct set of essays that explain why the absence of the metric system in the US is detrimental to our personal heath and our economy. These essays are separately available for free on my website, but the book has them all in one place in print. The book may be purchased from Amazon here.
The second book is titled The Dimensions of the Cosmos. It takes the metric prefixes from yotta to Yocto and uses each metric prefix to describe a metric world. The book has a considerable number of color images to compliment the prose. It has been receiving good reviews. I think would be a great reference for US science teachers. It has a considerable number of scientific factoids and anecdotes that I believe would be of considerable educational use. It is available from Amazon here.
History, in many popular works of science, is either the product of centuries of oral tradition, created from whole cloth, that has been solidified and certified when put into prose form, and then indefinitely repeated, or skimmed over and misunderstood. The new book The Perfectionists — How Precision Engineers Created the Modern World by Simon Winchester is a curious work. At its beginning, the book indicates, rather furtively, that the metric system is important, and therefore appears in an afterword section at the end of the book.
Each chapter of the book leads a reader to expect that a new world of increased precision will be encountered. Chapter 1 — (Tolerance: 0.1), Chapter 2 (Tolerance: 0.0001), this continues until finally we reach Chapter 9 (Tolerance: 0.000 000 000 000000 000 000 000 000 000 000 01). I will give him a minute amount of credit in that he at least used triads separated with spaces, but when one has a tolerance, one generally offers a unit.
We will suspend talking about the body of this book for a moment to discuss Winchester’s exposition about the metric system. Amazingly he has, with slight reservations, accepted John Wilkins as the creator of the metric system. In my view Wilkins developed the system part of the metric system, and decimal notation was adopted to complete it. Winchester starts by describing Galileo’s analysis of a pendulum, and then moves on to Wilkins:
A century later an English divine, John Wilkins, proposed employing Galileo’s discovery to create an entirely new fundamental unit, one that had nothing to do with the then-traditional standard in England, which was a rod that was more or less officially declared to be the length of the yard. In a paper published in 1668, Wilkins proposed quite simply making a pendulum that had a beat of exactly one second–and then, whatever the length of the pendulum arm that resulted would be the new unit. He took his concept further: a unit of mass could be made by filling the resulting volume with distilled water. All three of these new proposed units, of length, volume, and mass, could then be divided or multiplied by ten—a proposal which made the Reverend Wilkins, at least nominally, the inventor of the idea of the metric system. Sad to say, the committee set up to investigate the plan of this remarkable figure never reported, and his proposal faded into oblivion. Page 332-333
When I read this, I realized it had at least a pair of misconceptions. First the resulting volume of a one meter cube is not what Wilkins proposed to fill with water, he proposed a cube that was one-tenth of the base length. I don’t know what Winchester means by the committee never reported, as his system was published by the Royal Society in 1668.
Pat Naughtin was of the impression that Wilkins’ monograph was a dud. This is not the case. Wilkins’ biographer made it clear that his work was influential at least into the mid twentieth century. Winchester then indicates that Tallyrand:
“…..exactly duplicated Wilkin’s ideas, refining them only to the extent that the one-second beating pendulum be suspended along the latitude of 45 degrees North.
Apparently Winchester is viewing the duplication as independent, when parsimony would probably argue for transmission.
The author further indicates that only measurements of the Earth were then considered. A very complex seconds pendulum was constructed in France, and measurements taken. Thus far, I’ve not found documentation which indicates if it was to be a backup, should the Earth measures become impossible to complete, but this is a reasonable conjecture.
Early in the book, the Antikythera mechanism is discussed, and its accuracy was impugned both for its poor construction and the general theory of the heavens it attempted to employ. I found this astonishing, when compared with the PBS Nova episode, Ancient Computer, which shows an amazing command of theory and fabrication. Winchester offers a bibliography, but no end notes. I do not see a book about the Antikythera mechanism.
The book’s use of measurement units is a pigfish roasted on a spit. Early in the book, most of the discussion was about English machining, and so the introduction of Olde and New English units made some sense, but there is apparently no impetus to provide metric equivalents. Later in the book his choice of unit use seems almost random.
When Winchester uses metric, he often uses them with a fractional description:
… for a lock to merely work required a tolerance of maybe a fifth of a millimeter; to insure that it not only worked but was infinitely interchangeable, he needed to have the pieces machined to a fiftieth of a millimeter.” pg 100.
He could have just as easily said 200 micrometers for it to work, and 20 micrometers to be interchangeable, or ten times the tolerance.
His idea was to create as set of gauge blocks that, if held together in combination, could in theory measure any needed dimension. What, he wondered, was the minimum number of blocks that would be needed, and what should the sizes of the various blocks be? By the time he stepped off the clanking steam train at Eskilstuna station, he had solved the problem: with just 103 blocks made of certain carefully specified sizes, arranged in three series, it should be possible, he said, to take some twenty thousand measurements in increments of one one-thousandth of a millimeter, just by laying two or more blocks together. pg 168
Indeed one-thousandth of a millimeter is very descriptive, but he could also mention this length is a micrometer. He goes on:
…according to his biographer, has since “directly and indirectly taught engineers, foremen and mechanics to treat tools with care, and at the same time giving them familiarity with [dimensions of] thousandths and ten thousandths of a millimeter.
A ten thousandth of a millimeter is 100 nanometers, and that is very impressive. Visible light has wavelengths that span from violet at 380 nanometers to red at 750 nm. Wow! light of this wavelength is so high in frequency that we cannot see it with our eyes, and Carl Johansson created a method that measured to this precision. Context is important, and I don’t see much of it in this work.
There is a completely egregious mixing of centimeters and millimeters. On Page 208 a non-conforming jet engine part is described: “It was a pipe no more than five centimeters long and three-quarters of a centimeter in diameter.” The diagram that accompany’s the prose has a legend in millimeters. Longtime readers know that if I was Simon Winchester’s editor, I would fine him at least $5.00 or at least 500 cents for each use of the word centimeter in his manuscript. It is a strange and proverbial rationalization that “too much precision is a problem.” Millimeters are just “too small” to describe everyday objects—too precise. Teachers offer this Jackalope Tale “wisdom” that has been received generation after generation without any introspection. The Qantas Airline Flight 32 engine failure Winchester discusses is an excellent example of how widespread and pernicious this idea can be. Like with the failure of the Space Shuttle Challenger, the exception slowly becomes the rule. The report on this engine failure used the word “cultural” to describe why the parts were not fabricated to their specification. The author states:
What the report also noted, however were the failures within Rolls-Royce: the failure to machine a critical part properly, the failure to inspect properly, and the failure to reject what were called “non-conforming” parts, and to allow them to pass into service, with potentially lethal consequences. The delivery of such engines to Qantas was far from unique: hasty inspection soon after the accident revealed that scores of Hucknall-made oil pipes with misaligned walls thinner than half a millimeter had already gone into service, with the consequence that no fewer than forty engines, in use by Singapore Airlines and Lufthansa, and on all the remaining five Qantas aircraft, needed to be withdrawn from use and repaired. page 211
The money shot from the failure analysis report Winchester quoted verbatim:
Large aerospace organizations are complex sociotechnical systems made up of organized humans producing highly technical artefacts for complex systems, such as modern aircraft. Due to the inherent nature of these complex sociotechnical systems, their natural tendency is to regress if not constantly monitored—and occasionally even when monitored vigorously. This natural regression can occur due to the pressure applied via global economic forces, the requirement for developing growth, profit and market share…….. page 212
And in my view, an inculcated belief in “too much precision.”
The questionable numerical exposition continues throughout the book:
And the mechanical polishing and grinding of the lenses themselves are performed to one-quarter lambda, or one- quarter of the wavelength of light, with lens surfaces machined to tolerances of 500 nanometers, or 0.0005mm. And with the aspherical lenses that cut so markedly down on the tendency at wide apertures to display spherical aberrations, machining of the glass surfaces is performed down to a measurable 0.03 micrometer, or 0.00003 mm. Page 228
Seriously, he introduces 500 nanometers and then does not use a direct comparison! How about 500 nanometers and then down to 30 nanometers. That’s more than ten times better, and way smaller than the 100 nanometers of a gauge block, and in terms of light, well, very small.
Throughout the book are random mixtures of angstroms, microns, fathoms, yards, miles, inches, centimeters, feet, ounces, and probably more. Winchester states that the thickness of a silicon wafer is: “an exact two-thirds of a millimeter thick.” This would be 0.6666666… mm exactly? That must be one infinitely precise measuring device that does quality control on that wafer.
When discussing clean room standards he states: “ISO number 7, which allows there to be 352,000 half-micron size particles in every cubic meter of air.” Yes, half-micron or 500 nanometers? ISO 1 “… permits only ten particles of just one-tenth of a micron per cubic meter.” One-tenth of a micron? Perhaps 100 nanometer? This is a sad amount of numerical verbosity.
To me, this poor use of numerical grammar looks as bad as an obviously poor use of English grammar would to a copy editor. The gatekeepers of science writing would not put up with: “I thinks Jupiter big planet and much mass of planets in orbit round sun,” but the numerical use found in this book is sent right through their copy editing, apparently without a thought.
The final chapter, On the Necessity for Equipoise, causes one to wonder just what the book was about in the first place when he states:
For might there be in the wider world, in truth, simply too much precision? Might today’s singular devotion to mechanical exactitude be clouding a valued but very different component of the human condition, one that, as a result, is being allowed to vanish?
Apparently this author had a difficult time distinguishing between Art and Engineering?
The final send-off at the end of the book describes the gift of a tree, that is said to have its ancestry tracing back to the famous tree from which Newton saw an apple fall. That was when I knew I could not give this book a positive review. The story of the apple was almost certainly fabricated and promoted by Newton to keep from being accused of being in league with alchemists. The tree in the history of science is as mythical as the golden fleece. It is a good metaphor for a book with a promising subject, precision, which is all about numerical quantities, that are used as metaphors instead of descriptors.
If you liked this essay and wish to support the work of The Metric Maven, please visit his Patreon Page and contribute. Also purchase his books about the metric system:
The first book is titled: Our Crumbling Invisible Infrastructure. It is a succinct set of essays that explain why the absence of the metric system in the US is detrimental to our personal heath and our economy. These essays are separately available for free on my website, but the book has them all in one place in print. The book may be purchased from Amazon here.
The second book is titled The Dimensions of the Cosmos. It takes the metric prefixes from yotta to Yocto and uses each metric prefix to describe a metric world. The book has a considerable number of color images to compliment the prose. It has been receiving good reviews. I think would be a great reference for US science teachers. It has a considerable number of scientific factoids and anecdotes that I believe would be of considerable educational use. It is available from Amazon here.
