2025-01-30

An editorial in the Wetzel Chronicle, New Martinsville, West Virginia, argues for the simpler metric system in preference to the US measurement system.

He concludes the article with this sentence:

If our young generation finally learned the measurement system underlying physics and engineering, the U.S. might stand a chance of regaining our lead in these sciences in the next 30 to 40 years.

2025-01-30

In a letter to the editor of the Vail Daily, a local Colorado newspaper, a British surveyor living in Colorado argues that the US should complete its metrication

Proposal: The SI base unit of mass should be the gram****. See edit.

Some brief background. The amount of mass now called a kilogram was originally slated to be called the grave (pronouned grahv) and would serve as the base unit of mass (then, weight). For irrelevant linguistic reasons, the name grave was eschewed and so they, whoever they were, decided to use the gram, already established as a small unit of weight. Thus, they could not make the gram as heavy as the proposed grave, so they made the grave the kilogram.

In this way, the kilogram became the base unit of weight (now, mass). At this time, and for a long time thereafter, the kilogram was defined by a physical artifact kept in Paris, the standard by which all other kilogram weights were checked. In the early days, it would have been impractical to make an artifact of one little gram to serve as the standard.

Two things have happened since that make my proposal feasible and minimally disruptive. But first, my reasons for wishing to change the SI base unit of mass from the kilogram to the gram.

The modern metric system, the SI in particular, is nothing if not elegant. I'm an American and am just now learning about the SI and how the units work together. It's an impressive accomplishment and has a certain beauty to it. The only oddity remaining, a vestige left over from historical circumstance, is that one of the seven base units carries a prefix—the kilogram.

Consider the following chart.

Length. Base Unit: Meter

|| || |Multiply by|To get| |1 000 000|megameter| |1 000|kilometer| |100|hectometer| |10|dekameter| |1|meter| |0.1|decimeter| |0.01|centimeter| |0.001|millimeter| |0.000 001|micrometer|

There is a balance around the base unit that is elegant and sensical. Now consider the chart below.

Mass. Base Unit: Kilogram

|| || |Multiply by|To get| |1 000 000|gigagram| |1 000|megagram| |100|no such unit| |10|no such unit| |1|kilogram| |0.1|hectogram| |0.01|dekagram| |0.001|gram| |0.000 001|milligram|

This chart does not have the same symmetry or the same beauty. The prefixes don't match the multiplier of the base unit! It's all off kilter because the base unit comes awkwardly prepackaged with its own prefix. In fact, if you think about, the gram is already is the de facto base, isn't it? If the kilogram is the kilo-gram, the 1000-gram unit, then we are already treating the gram as the base in a sense. Why not align this with the actual system as expressed on paper?

Two proposals could remedy this problem. The more radical proposal would be to rename the kilogram the grave, and let everything else fall into place. The unit of mass we now call the gram would be the milligrave, and so on. We would have new units all the way up and down the mass scale. Obviously, this is untenable because the gram system is too well established. This would instantly render all papers and documents using *grams outdated, which is ridiculous and unnecessary.

The other solution is to make the gram the base unit. The two things that have happened to make this a feasible move are 1) in 2019, the kilogram was defined mathematically in terms of a natural constant rather than by a physical artifact, and 2) the metric system, in the form of the SI, now has an official steward in the BIPM with periodic CGPM meetings held so that just such changes and tweaks can be considered and implemented by the actual governing body for the SI.

My proposal would require two manageable adjustments. One would be updating SI documentation. That is done periodically at the conventions anyway. The other would be taking the definition of the kilogram and rejiggering it into the definition of the gram. I am talking about the mathematical formula that defines the kilogram in terms of Planck's constant. I am no scientist, but I am sure this would not be hard. (Couldn't you just take the current formula and put it over 1,000? There's probably a better way. I'll let the scientists figure it out.) Picture the above chart with the gram at the center. It would exhibit grace and logic.

Small changes are made to the SI all the time by the BIPM. Usually, these only concern metrologists. This change would be more visible than most, but because it would have no affect on units, would not be disruptive.

Nothing that has been written using *gram units would be affected in any way. In terms of our continued use of *gram units, from science to cooking, nothing would change at all. A gram would still be a gram, and a kilogram would still be a kilogram. Indeed, at the end of the day, this is merely an aesthetic change (which is what makes it so plausible), yet one I feel is important. The more I learn about the SI, the more I like it. And the more I like it, the more the kilogram as a base unit bugs me. If it's the base, why is it kilo-? It feels like the one remaining wrinkle to be ironed out, the one small ill-fitting puzzle piece to be moved into its proper position so that everything snaps perfectly into place.

I haven't checked, but I have no doubt I am not the first person to suggest the foregoing. I am just some random guy who thinks millimeters are easier than inch fractions and got excited about it. Hopefully someone with actual influence in the international metrology world could push for this. Or, am I totally off base here?

EDIT: or, How I Learned to Stop Worrying and Love the Kilogram. Thanks to all of you who gave me insightful feedback. I have learned more about what makes the SI a "coherent system" and how changing a base unit would have ripple effects throughout the system. SI derived units (and there are many) depend on mathematical relationships between base units. Anyone interested can read about derived units in NIST special publication 330, section 2.3.4, including what is meant by "coherent." In short, there are many units for measuring all sorts of stuff whose definitions depend intricately on the base units of the SI. The SI base units have been chosen purposefully, and there is a reason they are called "base" units. The SI is the modern form of the coherent metric system, which went through several iterations, as a couple people pointed out. Whether a base unit is a meter or centimeter or whether it is a gram or kilogram matters and affects the derived units. For this reason, my proposal is not "merely an aesthetic change," as I stated previously. In fact, my proposal would be fairly radical and create a whole host of headaches as base unit dependencies cascade down. So changing the base unit to the gram is out. Somebody get BIPM on the horn for me and tell them I rescind my proposal.

I'm wondering if speeds measured in km/h are truly metric.

2025-01-21

newskarnatka.com, an Indian news website writes about the Body Mass Index, (BMI) and also the Basal Metabolic Rate, (BMR,) which determines the number of calories (or joules) the body needs to function. The article also mentions the limitations of the BMI measurement.

The BMI calculator uses a simple mathematical formula:

Metric system: Divide weight in kilograms by height in meters squared.

Imperial system: Divide weight in pounds by height in inches squared then multiply by 703.

This BMR calculator allows you to enter your details in metric or US units to find your BMR.

Brazilian here. I have access to some FTA TV channels from the US, including CBS News.

They just started CBS Saturday Morning by mentioning that Trump’s inauguration on Monday will have to take place indoors because of ‘minus five degrees Celsius temperatures’.

That was somewhat surprising to me, because when watching US-produced content I’m always expecting temperatures to be quoted in Fahrenheit.

Im 16 and live in the US and I literally cannot see how people use “foot” or something to measure stuff? But I could say “this thing is like whatever meters long” so does this mean it’s working cause then it just feels like it’s just old people refusing to switch over and are holding back the new generation like even drinks are getting labeled with liters instead of gallons I’ve noticed

2022-06-27

A traveler from Minnesota visits Iceland and finds that the metric system is no good for describing his feelings.

The meter was delineated by measuring the distance from the Equator to the North Pole, then dividing that by 10 million. In this way, we measure Earth abstractly, from above (as it were), and then decimalize the result to arrive at the ideal unit of measure. It is logical, perhaps, but it is alienating; the earth becomes an object of measurement, not a living home. Though the metric is a system based on the dimensions of Earth, it abstracts us from the earth, from our familiar landscapes, by making us quantify them from outside of ourselves.

He ends with:

To convey the strangeness of being in a fully sunlit room that late in the evening, I described to my friends in an email that the sun was still “three fingers above the horizon.” Three fingers, not .048 meters or 4.8 centimeters. . . .

Standing in Iceland, the blast of a geyser catches my eye, the hot steam cools into a heavy mist that touches my skin if I stand downwind of it, and the sulfuric stink of the volcanic action that drove the geyser’s explosion tangs my nose. I am awed by the sight, rinsed with the mist, and repulsed by the odor all at the same time. But my foot grounds my body in the environment in a way that a meter could not. Everywhere, a meter reduces our shared home to data; everywhere, the sun three fingers above the horizon elevates it to poetry.

(This was originally published two-and-a-half years ago, but it only surfaced in my search for news today.)

1874-01-08

An extract from the January, 1874 edition of Nature describing Lavoisier's contributions to the creation of the metric system.

(PDF available for download. One page, 405 kb.)

2024-11-23

In 1983 John Buchanan, the premier of Nova Scotia, decided to have road signs showing distances in both kilometres and miles.

"What I'm doing is giving people the right that they should have in this country, the right that I believe they have under the law to have that option of either miles or kilometres," Buchanan said, explaining the rationale for slapping Imperial distances alongside metric measurements.

(Canada started its metric conversion in 1975, 50 years ago, so we will probably see a few stories about its metric conversion this year.)

I've recently heard that during the French Revolution, the French also tried to metricized the traditional 360 degree angle system, resulting in the Gradian/Gon measurement. Apparently, it's still used in certain European countries for surveying and the French military uses it to an extent. My question is what are the advantages and disadvantages of this system and is it better than the traditional 360 degree system?

I’ve read some research and am struggling to work out if they are in fact talking about the same measurement or not. One states 750ug/L-1 and the other states 0.75ug/mL. Is this the same thing or are they different I’m struggling thanks 😅

2024-12-31

Canada's metrication programme began in 1975 with temperatures being given in degrees Celsius on 1 April.

Some people missed the announcement that this was a permanent change and believed that this was an April Fool's Day prank.(Une farce de la poisson d'avril, pour les quebecois.)

The joke was on them on April 2.

2024-11-07

In iconnect007, an online magazine for the electronics industry, an electrical engineer discusses the reasons for using metric measurements in the design of printed circuit boards, and the reasons why US measures are still in use.

I know this sub is an echo chamber. But are there any ideas for metrication that poll well or have a chance at happening in the US?

My proposed plan since we can't seem to move away from Imperial:

• Decimal gallon for volume
• Decimal foot for length
• Decimal pound for weight, shall now be standard

New prefixes: b = one-billionth, mm = millionth, t = one-thousandth/thou, h = one-hundreth, Ḿ = thousand/k = kilo, MM = million, B = billion, T = trillion, Q = quadrillion. Anything bigger/smaller than these set units should typically be put in scientific notation

New base 10 units will eventually be standard. As for formatting? Here are examples using old unit equivalents:

- Inch = .083 ft / 8.3 one-hundreths feet (hft)

- A mile is now 5.28 kilofeet (kft) / 5.28 thousandfeet (Ḿft),

- A table spoon (1/256 gal) is now 3.91 thousandths of gallon/ 3.91 tGal,

- A US ton (2000 lb) is 2 kilopounds (klb, or kip)/ 2 Ḿlb

- As example for height, measuring people will be by 1/10 ft (1.2 inches), so most measuring tapes should typically have .05 ft (1/20') marked as well if you want precision.

https://live.athletictiming.net/meets/42307/events/xc/1529946

It's not unusual to see 5 km runs for cross country (you will still see 3 mile runs in places with a long history of cross country like California or Illinois), but it is unusual to have only 1 km splits, and hardly any mention of 1, 2 or 3 mi splits, or a "2.1 mi" split (5 km - 1 mi, AKA 1 mile to go).

If you watch the race, the only sign of Freedom Units are posts at 1 mi and 2 mi (no timing mats), and a note on the map that the last straightaway is 200m, so you can work out 4828m (3 mi) from there. The girls winner ran her last 1 km in 200.0 seconds (3:20.0), so she was cruising along at 1000 m / 200.0 s or 5.000 m/s. 5.6 seconds to cover the 28 m from 4800m to 3 miles, easy!

I’m from the us so we don’t really have anything better than miles to describe large distances on earth, are Megameters commonly used? I was finding the great circle distance between two airports, and was wondering if it was too pedantic to describe it as 7 Mm instead of 7,000 km.

Let's say the French are too busy in the 1700's. The Metric system never really takes off and is basically forgotten. What happens next?

It seems that every country uses either metric-only or dual-labeled speedometers. Do any countries use speedometers that only show miles per hour?