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In Praise of the Imperial System of Measures

It puts the metric system to shame

Paul Krzyzanowski – July 18, 2021

Many of you reading this grew up in countries that use the French system of measures, politely rebranded as the “metric” system. Since you were raised with it, you may never have stopped to consider that an alternative exists. Not just an alternative, but a better one. The Imperial system, developed over centuries by farmers, brewers, and surveyors rather than by Parisian committees, is more intuitive, more practical, and more deeply connected to the things it measures.

The French devised the meter in the 1790s as one ten-millionth of the distance from the equator to the pole. Unfortunately, the surveyors miscalculated, so the “rational” unit was wrong from the beginning. In contrast, the Imperial system was not born in a café over a geometry problem but in the field, on the road, and in the workshop. It was built to fit life, not ideology.

Why Tens Don’t Work

Factors of ten are not intuitive, not easy to visualize, and they do not divide cleanly. This is why for thousands of years they were rarely, if ever, used in units of measure. “Let’s multiply by 10” was not an amazing innovation but an affront to practical applications of measure. People needed units that divided into halves, thirds, and quarters, not endless strings of decimal places.

The Roman foot, for instance, was divided into 12 uncia (inches) or 16 digiti (a digitus being a finger). Even the French, before their revolution, used a foot: the pied du roi or “the king’s foot.” This was divided into 12 pouces (inches), and each pouce could be further divided into 12 lignes when precision was required. Six feet made a toise, which was the French version of a fathom. In practice, everyone recognized the utility of twos, threes, fours, and twelves. Only later did revolutionary reformers insist that tens must rule all things.

Many of you reading this grew up in countries that use the French system of measures, politely rebranded as the “metric” system. Since you were raised with it, you may never have stopped to consider that an alternative exists. Not just an alternative, but a better one. The Imperial system, developed over centuries by farmers, brewers, and surveyors rather than by Parisian committees, is more intuitive, more practical, and more deeply connected to the things it measures.

The French devised the meter in the 1790s as one ten-millionth of the distance from the equator to the pole. Unfortunately, the surveyors miscalculated, so the “rational” unit was wrong from the beginning. In contrast, the Imperial system was not born in a café over a geometry problem but in the field, on the road, and in the workshop. It was built to fit life, not ideology.

Lengths: The Rod, the Furlong, and Friends

Imperial measures of length are a masterclass in practicality. The rod (16.5 feet) leads neatly to the chain (66 feet) and the furlong (220 yards). Eight furlongs make a mile. This is not abstract; it is how land was measured, how horses ran, and how farmers worked.

Horse racing still uses furlongs: 5, 6, 8, 10, and 12 furlongs. These distances are easy to remember and have rhythm. Compare them with their metric equivalents—1,000 meters, 1,200 meters, 1,600 meters—numbers no one bothers to memorize.

Sidebar: A furlong's origin “Furlong” literally means “furrow-long,” the distance an ox could plow before taking a break. It is one of the few units that still whispers of sweat, soil, and the length of a working day.

Sports Fields and Races

The Imperial system has the good taste to produce a football field exactly 120 yards long (including end zones). This divides naturally into halves, quarters, and first downs of 10 yards. Now imagine a field 109.728 meters long. Metric football would be unwatchable, with referees carrying calculators instead of chains.

The marathon is another fine example. It is 26 miles and 385 yards, a distance memorable precisely because of its eccentric origin: the 1908 Olympic course was lengthened so the race could finish in front of the royal box. That is character. The metric equivalent is 42.195 kilometers, a number that looks like the result of a broken typewriter. Nobody brags about running “42.195.” They say “26 miles.”

Sidebar: Runners and miles
Elite marathoners still pace in minutes per mile, even under metric clocks. The numbers refuse to die because they work.

Land: Acres vs. Hectares

An acre is one chain by one furlong. Farmers could pace it out, no calculator required. The hectare, by contrast, is 100 meters by 100 meters, producing 10,000 square meters of abstraction. Farmers in France may have adjusted, but only with tape measures.

Sidebar: The hectare’s invention
The hectare was introduced by French revolutionaries who thought 100 was more elegant than 660 by 66. In their enthusiasm for neat numbers, they overlooked the fact that nobody actually imagines a 100-meter square.

Liquid Measures

Imperial liquid units match human life. A pint fills a glass, two pints make a quart, and four quarts a gallon. Larger measures scale sensibly: barrels, hogsheads, and tuns. Each cask size was designed for real handling, rolling, and shipping.

The French would collapse all barrels into cubic meters, ignoring the obvious fact that a barrel of beer is not a barrel of oil. The Imperial system wisely gives us a U.S. oil barrel (42 gallons), a beer barrel (31 gallons), an ale barrel (32 gallons), and wine and beer hogsheads, each distinct. To confuse ale with beer, or beer with oil, would be absurd. The French, however, would happily serve you a cubic meter of any of them.

Dry Measures

Dry measures, too, are rooted in reality. A bushel is the grain that fits in a bushel basket. A peck is a quarter of that, carried in a sack. These are measures with handles. Metric equivalents describe volumes in cubic centimeters, which might be useful in chemistry but not in an orchard.

Weights: Stones and Hundredweights

The stone, at 14 pounds, is still the natural measure of body weight in Britain. A man is “11 stone,” not “70 kilograms.” The number fits the frame.

The hundredweight (112 pounds) is another example of sensible irregularity. Its value divides evenly into quarters and stones, which is what mattered in trade. Metric’s 100-kilogram multiples may be clean, but they are useless when actually buying and selling.

Weights: Troy vs. Avoirdupois

Imperial measures even recognize that some things are different enough to require their own systems. Avoirdupois is for everyday goods: 16 ounces to the pound. Troy is for precious metals: 12 ounces to the pound. This distinction avoided cheating in trade and reflects the practical truth that gold and coal do not belong in the same scales.

Metric collapses everything into grams and kilograms, as if diamonds and potatoes deserve the same measure. Only the French could see this as an improvement.

Temperature

Celsius makes water the star of the show: 0 for freezing, 100 for boiling. Fahrenheit, in contrast, was built for people. Zero is the freezing of brine, useful in northern winters. 100 approximates body temperature. Between them lies the entire human comfort zone, measured in increments fine enough to matter.

Celsius requires you to remember that “22” is pleasant, “30” is sweltering, and “40” is dangerous. Fahrenheit tells you directly: 72 is perfect, 90 is hot, 32 is freezing. Clear, human, and practical.

French Experiments with Decimal Time

So enamored were the French with multiples of ten that they attempted to reform not just length, weight, and volume but time itself. The French Republican Calendar, introduced during the Revolution, divided the year into twelve months of three ten-day weeks, or décades. The days were called primidi, duodi, tridi, quartidi, quintidi, sextidi, septidi, octidi, nonidi, and décadi. Sunday vanished, replaced with décadi.

Decimal time went even further. Each day was divided into 10 hours, each hour into 100 minutes, each minute into 100 seconds. A normal day thus had 100,000 seconds, each slightly longer than the old ones. It was an accountant’s dream and everyone else’s nightmare. The system proved too much even for France, and Napoleon abolished the entire calendar and decimal time experiment on January 1, 1806.

The Metric Virtue

The defenders of metric point out that conversions are simple. Everything is based on 10. This is its single virtue. But decimal neatness is less useful than context. Real people do not convert grams to kilograms daily; they buy a bushel of apples or a pint of beer.

The Persistence of Tradition

Even in countries that claim to be fully metric, traditional units refuse to disappear. You do not go to Ireland and order 568 milliliters of beer; you order a pint. The ligne—1/12 of a pouce—remains in use among French and Swiss watchmakers and in ribbon manufacture.

The entire world measures screen sizes in inches; nobody boasts, “I just bought an 812.8-millimeter monitor.” Standard shipping containers, whether leaving Shanghai or Rotterdam, are 8 feet wide, 8 feet 6 inches high, and either 20 or 40 feet long. Crude oil is measured in barrels (a convenient 42 gallons, versus 59 gallons for a standard wine barrel or 60 gallons for a standard Burgundy barrel). The global economy runs on Imperial dimensions.

Conclusion

The metric system was imposed from Paris during the French Revolution, like so many other bad ideas. It is a system for bureaucrats and scientists, designed to be tidy on paper. The Imperial system is untidy, but it works. It reflects how people live, how they measure, and how they trade.

You must decide whether you want a system shaped by oxen, brewers, jewelers, and runners, or one designed by French revolutionaries with rulers. If you have ever walked a furlong, poured a pint, or stood on a football field, the answer is obvious.

Appendix: A Conversion Chart for the Metric-Raised

For those who grew up with the French system, here is a handy chart showing the “rational” metric equivalents of proper Imperial measures.

Each Imperial unit converts, but always into metric nonsense. The neat decimals of metric, when applied backward, produce absurdities. Which only proves the point: the Imperial system fits reality; the metric system fits only paper.

Guide to Proper Usage

For readers accustomed to metric, here is a primer on when to use the proper Imperial units in daily life:

In short, use Imperial units whenever describing the things that matter: land, drink, livestock, weather, sport, and self. Reserve metric for measuring microscope slides and calibrating lasers.