By The Metric Maven

Thanks to the Patrons who are supporting me on Patreon! We will be alternating between a new Metric Maven essay, and a new Chapter of Death by a Thousand Cuts: A Secret History of the Metric System in The United States each month. Next month Chapter 2 will be published. Now for this month’s essay:

In recent months, I had lunch with my friend and colleague Dr. Don. I presented him with a copy of the Dimensions of the Cosmos, and related that Australians and others use nothing but millimeters when constructing a house. Despite his considerable education, incisive mind, and knowledge, the answer was predictable for an American. He said “the numbers are too big.” I assured him this was a ubiquitous notion that is entirely wrong. After I explained why millimeters work so well, he indicated he understood, but like most Americans, it will probably not alter how he measures in the future.

The use of centimeters as a pseudo-inch is so natural to Americans that any deviation from relating inches to centimeter “metric inches” is thought to be ramblings of a fool in the face of “obvious” knowledge. The destructive anti-meme of centimeters was (is?) on display for all the English speaking world to view on Wikipedia (2017-11-21). The current page on tape measures is quite a mess, and the page is flagged as needing scholarly sources. The text in the entire article has inches, and centimeters without a prose mention of millimeters in the body of the article.

They discuss tape measures in the United States, but it’s centimeters all the way down with a shout out to an imaginary three scale problem of adding metric divisions:

Some tapes sold in the United States have additional marks in the shape of small black diamonds, which appear every 19.2 inches (48.77 cm). These are used to mark out equal spacing for joists (five joists or trusses per standard 8-foot (243.8 cm) length of building material).

Many tapes also have special markings every 16 inches (40.6 cm), which is a standard interval for studs in construction. Three spaces of 16 inches make exactly 4 feet (121.9 cm) which is the commercial width of a sheet of plywood, gyprock or particle board.

It should also be mentioned that the sale of dual metric/customary scale tapes is slowly becoming common in the United States. For example, in some Walmarts there are Hyper Tough brand tapes[10] available in US customary units and Metric units. Unlike US rulers, of which an overwhelming majority contain both cm and inch scales, tape measures are longer and thus traditionally have had scales in both inches and feet + inches. So, inclusion of a metric scale requires the measuring device to either contain 3 scales of measure or the elimination of one of the customary scales.

When the UK is mentioned, it’s centimeters all the way down:

Tape measures sold in the UK often have dual scales for metric and imperial units.

Like the American tape measures described above, they also have markings every 16 in (40.6 cm) and 19.2 in (48.8 cm).

The strangest aspect of this Wikipedia page is the illustrations. A US tape measure is shown that is capable of measuring to the nearest 1/32 of an inch with (0.79375 mm) for reference? Why not just put 794 um? That sounds even more accurate.

The next illustration shows a millimeter only metric tape measure, but never mentions this fact. Here is how it appears on the Wikipedia page:

Below that is a dual scale (they don’t designate US and metric) tape measure with inches and centimeters on it:

The use of inches and centimeter pseudo-inches is so automatic, that the difference is never acknowledged even when it is staring them right in the tape measure. The assertion that numbers in millimeters would be too large is a unexamined fictitious restriction, or as those people who write vacuous pop business tomes might say, they’re not thinking outside of the box.

I have written for and edited Wikipedia articles in the past. I logged-in and made these changes to the article on 2017-11-21:

I also changed the absurd number of decimal places on the 1/32″ illustration:

The Wikipedia page was almost certainly authored by an American, and reflects the intellectual blindness of the difference between millimeters and centimeters. Before my edits, there was no notice of the difference in the illustrations. Time will tell if my edits are erased or reversed. I only changed the US section to millimeters as I do not feel knowledgeable enough about other countries to edit their entries.

I often find myself feeling like a reverse-time fossil hunter. I have all these metric millimeter only tape measures that I can only hope could become ubiquitous in the US at some future time. Below is a number of future non-fossils, plus one that I hope will

become extinct and morph into a curiosity:

One can clearly see that in Australia, millimeter only metric tape measures are plentiful and utilized. In the US, the very notion of a millimeter only metric tape measure is intellectually dismissed instantaneously because of an ingrained cultural urban legend that large numbers are a problem. Strangely, this is never applied to using feet for altitudes of aircraft or the elevation of mountains. Teachers in our schools, the scientists in our universities, the engineers in our corporations, and Jane and Joe American have all absorbed this intellectual anti-meme to the point it is proverbially believed, and ubiquitously employed, to dismiss millimeters as the best metric unit of length for everyday work. This is the “intellectual” argument offered. The path of least thought is to equate the use of inches with centimeters, and claim to have “gone metric.” As I’ve stated in the past, this is simply using the metric system with the same poor usage of Ye Old English “customary” and improving the situation not-at-all.

In the figure above, there are eight things, and one does not belong. It is the US centimeter/millimeter, or if you prefer, centimeters with tenths of centimeters tape measure at the bottom. What a person sees upon casual inspection is all integer values, but in the case of centimeters, their size must generally be broken into smaller divisions for any practical everyday use, that could more easily be expressed in millimeters.

There is not just a physical invisible metric embargo in the United States, there is also an unconscious intellectual metric embargo woven into the fabric of our educational system and society. Until we find a way to deal with the immediate dismissals that act as Pavlovian reactions that inoculate Americans from thinking about the metric system, we will never see it in the US.

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