Meter standard
The platinum/iridium bar that was the meter standard up to 1960. The definition is now based on a fraction of the speed of light.

A simple question I am often asked is how the price of gas in England compares with the price here. A simple query, but life is complicated and, sure enough, complications attend this question because there are a couple of variables that enter into a meaningful conversion. Both of these have been varying widely during the last weeks due to the political and economic turmoil that currently besets the UK. The first of these is the exchange rate of pounds sterling to dollars, and the second is the fluctuating cost of oil. In addition, it has to be remembered that a U.S. gallon is about 20 percent smaller than an imperial gallon. This is the reason why miles per gallon figures on identical cars in Britain look much rosier than in the U.S. The price of petrol in the U.K. is currently around £1.62 per liter, and if you follow the conversion through its intricacies, it becomes $6.93 to compare with the current U.S. price of gas at $3.70.

Speaking of complications, I grew up in the postwar period when the currency in Britain was pounds, shillings and pence (also halfpennies and farthings, which were a quarter of a penny), so my primary education included arithmetical operations with that currency. There were 12 pennies to one shilling and 20 shillings to a pound. How today’s teenagers would do, who can’t seem to calculate change on a decimal transaction in their heads and have to refer to a cash register, I don’t know. However, I can feel a touch of the curmudgeon coming on so I won’t get into that discussion. Suffice it to say that decimalization of the currency in 1971 saved all that pound, shillings and pence rigmarole and made life much simpler.

Money has always been a major concern of monarchs, dictators and governments through the ages and so, too, have measurements and measures. This is largely because taxation, their chief source of revenue, has generally been based on the size or weight of things. More than two thousand years ago, the tax collectors of Egypt were measuring the area of fields of grain and coming up with an approximation to pi (π) in the process so they could include all parts of fields that were not rectangular. Mind you, pi was actually staring them in the face, as it were, from millennia before that, since the ratio of the perimeter of the Great Pyramid of Giza to its height is twice pi to an accuracy of 0.05 percent and who knows who built that? It’s one of the great ancient mysteries.

A close kin of currency decimalization is metrication—the adoption of a comprehensive decimalized system of weights and measures. The originator of metric is understood to be a church vicar of Lyons, France, named Gabriel Mouton. He first proposed a system in 1670 that French scientists further refined. Nowadays, the standard metric system used worldwide is the Système Internationale or SI units, covering seven basic units including the meter for length and kilogram for weight.

Prior to 1965, Britain had used and imposed on its empire the British Imperial System of units, which was first formalized by the Weights and Measures Act of 1824. It replaced an old system in use since the Middle Ages which was subject to a high degree of local variation. The “new” system was not standardized throughout the empire until 1926. In 1965, the country began the switch to the metric system used throughout Europe, mostly due to its impending union with the European Common Market. I well remember the teething problems the change imposed on the construction industry there, as I was working as a junior architect at the time. It did not seem that the “new” units fit well with human dimensions, millimeters and centimeters being too small, and meters being too large. It seemed, and still does, that the inch and foot described the human frame much better. Some imperial units remain to this day, such as miles, though both miles and kilometers are now appearing on some road signs, particularly in the southeast of Britain which is more frequented by European tourists. Miles per hour and miles per gallon (imperial) are still quoted in connection with motor vehicles even though petrol (gas) and diesel are only sold in liters.

Marble Block
In the 1800s, marble blocks inscribed with standard meter marks were incorporated in public buildings in France to promote metric measurement.

America is the real diehard, largely adhering to the imperial units in use in the British colonies prior to the revolution of 1776. This is why the U.S. gallon is smaller than the imperial gallon because it adopted as a gallon the wine measure in use at the time rather than what ended up as the imperial gallon. The units became the U.S. Customary Units in use today. This in turn means pints and quarts are smaller.

The U.S., in company with Liberia and Myanmar, are the only countries that now use the imperial system of units. In fact, metric measures became legal in the U.S. in 1866 and the Metric Conversion Act, a bill signed by President Gerald Ford in December 1975, declared the metric system to be the preferred system of units. However, it allowed the continued use of U.S customary units. Really only two factors have facilitated the continued use of imperial units: the enormous size of America’s internal market, and the leading position it has in technology. The internal market is sufficiently large to support the continued supply of goods made or built using imperial units. There is no external imperative that forces a change to metric. Equally, the excellence of American technology persuades overseas markets that it is worthwhile to support a dual standard of parts and goods—imperial and metric—in order to take advantage of it, despite the savings inherent in maintaining just one system. There are significant economic penalties inherent in any change as well as natural inertia to overcome. Naturally, those parts of the U.S. economy that deal with scientific activities, such as NASA, employ the metric system to better relate to similar entities overseas. The U.S. military also uses metric for similar reasons.

It takes a generation or more for a major societal change like metrication to stick. Many in Britain bemoan the loss of the old units, the furlong for instance (still used in horse racing circles), the rod, pole or perch, and the acre. The furlong was the length of a furrow plowed by a team of oxen in a day. It was 40 rods or perches, 10 chains, or 220 yards—the long side of an acre, the other side being 22 yards. Not many, apart from farmers and land agents, can picture the metric hectare, whereas many homesites are a half to one acre and therefore more easily visualized. People’s weight is still spoken of in stones (a stone is 14 pounds set by royal statute in 1350) and draft ale is still sold as imperial pints. Of course, it is the older generation who grew up with imperial units who have the most difficulty, and the majority will never really internalize how much 250 grams of something is. At best, it is thought of as about half a pound (actually about 10 percent more). In writing to my family members in Britain, I have to explain that a foot of snow is 300 millimeters (or 30 centimeters) or the temperature is 22º centigrade, having juggled the Fahrenheit temperature, minus 32, multiplied by 5/9ths = centigrade conversion in my head. Life is complicated.

© David Cuin 2022