Living in Japan I have come to love the metric system. When I read books from the U.S. to my kids, I always have to explain the system there and it becomes very confusing. How did other countries migrate to the metric system? What kept the U.S. from successfully implementing it?
Greetings all. Many of us lived through the days when our countries 'went metric', so just a reminder: as tempting as it may be to tell us all about it, this subreddit does not permit personal anecdotes. Please ensure that answers are based on solid source material, and meet usual sub standards. Thx!
In Europe in the late 1700s there were thousands of systems. They were often based on a kings physical features such as feet, hands, arms, stride, etc. This was incredibly confusing since you could travel a couple towns over and get a completely different foot. To make it worse a new king could mean a new measuring system. There was no google back then so finding out how many of your feet someone elses feet were was extremely difficult.
Science and engineering was also picking up speed and there was a need for a modern measuring system that was useful for those purposes. With the french revolution France wanted major change and wanted to reinvent itself. It was a time were old stuff got tossed away and new stuff was implemented. A part of this was the metric system. During the 1800s more and more European countries realized that having thousands of measuring systems in Europe was hopeless in an industrialized economy and started converting. Industralization and metrification are closley linked. As the European countries converted their colonies converted as well.
The next big wave of metric came with communism. The communists saw previous systems as symbols for old oppressive medieval societies. Metric represented the future.
Once we approached the middle of the 1900s it was only the Britain and the former colonies that resisted. These countries have always had a bad attitude towards metric partially because metric is associated with revolutionary movements and governments telling people how to do things. The US is also a huge country and a huge economy. Americans don't travel abroad much and the US is large enough to be different.
However the English world couldn't resist and had to adapt. Australia probably had the smoothest metrification of any modern country. Left is Burma, Liberia and the US. Both Burma and Liberia have started to turn metric.
Notice that just because a country officially adopted metric doesn't mean that the population does. In the 1800s it was mainly government contracts and markets that had to change their units. Most people used the old way for a long time just like you hear Britts use feet today even though decades have passed. Going metric takes a century or so.
The US is going metric. medical industry and the academic world was first. Since then a lot of sports, industry and education has gone metric. Everything for land surveying, to cars is metric today. Also there is a large influx of IKEA furniture, European wine and beer and Chinese products that are all in metric units.
The new big change is the internet. Wikipedia is mainly metric, many americans read none american bloggs and websites and many americans interact with metric people online. Slowly americans are shifting.
As noted above, Australia had a fairly smooth transition in the 1970s. Here is the government report on the process.
Part of the reason why it was simple was that in 1966 Australia had completed a conversion from the old-style pounds, shillings and pence to decimal currency; it primed the population to accept measurement unit conversion. The success of the conversion is also attributed to:
Edited to remove stupid typos.
In China what ended up happening is the traditional units were first standardized into units that corresponds to metric units and in base 10 system then officially switched to metric units all together. In Republic of China era a legislation called Republic of China Law of Metrication (中华民国度量衡法) was enacted in 1929 that made metric units an official "alternative" to traditional measurements while also standardized traditional measurements to base 10 and correspond to metric units. For example a unit called jin (similar to pound) used to weigh around 600g and was divided to 16 liang (similar to ounce), but the new law made one jin equal to 500 grams and 10 liang.
In PRC in 1959 the standardization of traditional units became official and in 1985 Law of Units of the People's Republic of China (中华人民共和国计量法) was officially in use. It made metric units the official units for all commerce in mainland China.
(Most people still use jin and liang when they buy produce and bulk items, although anything with packaging will have metric units only.)
This isn't about the metrification in the 20th century, but there's a curious historical aspect back in the 1790s. I doubt this has much to do with the US not adopting the metric system in the 20th century, but it might have had a lasting effect on the way the US Congress has dealt with weights and measures in general:
The US very nearly implemented its own metric (ie, decimalized) system in the 1790s, before the French. One of the Constitutional powers of Congress is to make a standard system of weights and measures, and one was needed in those days. In 1790 George Washington told Congress to do it and Thomas Jefferson was appointed to design a system, which he quickly did.
Jefferson had spent time in France of course and was well aware of the French efforts to design a "scientific" decimalized metric system. At first the French system was being built around the "seconds pendulum"—the length of a pendulum swinging once per second. I think Jefferson wrote to his French counterparts, seeking to work together to establish an international system, or at least a common basic unit. And the French scientists, at first, wanted an international effort. Jefferson used the seconds pendulum at 45° latitude (I think the French had been using the latitude of Paris, about 48°50').
The US had already abandoned the English monetary system for a fully decimalized one in 1785 (although it wasn't until 1792 that it was fully implemented). Jefferson saw the chance to establish a fully integrated and decimalized system of weights and measures, with everything linked together, including coinage. He understood that such a major change might be rejected by the American people, so his report to Congress proposed two systems, one more traditional (12 inches to a foot, 2 3 [oops!] feet to a yard, etc), and one fully decimalized.
His report has the catchy title "Plan for Establishing Uniformity in the Coinage, Weights, and Measures of the United States", and was submitted on July 13, 1790. You can read it here.
Both systems used the seconds pendulum as the basic reference unit, but the decimal system was much more systematic and very much like the metric system the French eventually made. Jefferson's system used old unit names like foot and mile, but there were 10 inches to a foot, 1,000 feet to a furlong, 10,000 feet to a mile, and so on. He even tied in the weight of a silver dollar, so the monetary system was taken into the larger system (although how that would survive inflation I don't know—presumably the weight of a dollar in silver would be adjusted over time).
The decimalized units were mostly fairly close to the traditional values. The foot was a bit longer, the bushel a bit smaller, although the mile was closer to 2 traditional miles.
Jefferson argued that the decimal system was far more "democratic", in terms of being useful for the common people. It would bring "the calculation of the principal affairs of life within the arithmetic of every man who can multiply and divide plain numbers". He added little details to make it easier for anyone to confirm units of measure on their own. The seconds pendulum was something anyone could confirm if they had a good clock (although there was a slight change over different latitudes). Another was the basic unit of weight, the ounce, which was based on the weight of a cubic foot of water. And one cubic foot was the basic unit of volume, the bushel. These kinds of things made it possible for ordinary people to confirm the entire system of weights and measures if they wanted, which Jefferson thought was vital.
Anyway, he submitted his proposal in July 1790. Congress was slow to act (mainly because, I think, they had a lot of things to do just then, and perhaps because Congress is usually slow to act without some crisis to push them, or money to be made). Jefferson's decimal system gained the support of Washington, Hamilton, Madison, Monroe, and others. Robert Morris opposed it, although I'm not sure why. Washington urged Congress over and over to get to work and adopt it. In late 1791 Congress made a committee to study it and make recommendations. In early 1792 the committee unanimously endorsed Jefferson's decimal system. But again Congress was slow to act.
It is interesting to note that Jefferson's decimal system was fully designed and ready to go well before the French metric system. While Congress delayed the French decided to abandon the seconds pendulum and base their system instead of the length of a meridian of the Earth. This necessitated a big and expensive study and voyage to measure, which annoyed Jefferson. It made the basis of the system something that could not be confirmed by ordinary people, and difficult even for states. This and other developments in France (I think some of the key scientists who had wanted an international system died or were replaced by others with a more French-oriented perspective, or had a vested financial interest in the voyage to measure the Earth's meridian) changed what had originally been meant to be an internationally developed system into a strictly French project. About it Jefferson wrote: "The element of measure adopted by the National Assembly excludes, ipso facto, every nation on earth from a communion of measurement with them."
Still, Congress considered Jefferson's decimal proposal and Washington urged them to pass it into law. Finally in 1795 a bill was introduced to do just that. The House passed it and a Senate committee approved. But the Senate didn't get to voting until the last day of the session and decided to take it up in the next session of Congress. The US was just months from passing into law the first metric (ie, decimalized) system.
But then an odd thing derailed everything. For years there had been war with Native Americans in the "Northwest" (ie, Ohio, Indiana, etc). The war came to an end in 1795. Vast amounts of land were ceded to the federal government, triggering a land rush. The federal government suddenly had an intense need for a standardized system of land surveying and measurement in order to deal with this (and make a lot of money selling the land). The Senate didn't take up Jefferson's system. Instead Congress worked on a land survey system. In 1796 Congress passed a law that defined a (non-decimal) survey grid using miles and chains. It was based on older survey systems for the practical reason that surveyors in the field were already using particular kinds of chains, acres, miles, etc. Basically a "scientific" fully-integrated system was dropped in favor of something quick and dirty that could be put to use as quickly as possible out on the frontier. The first unit of measure standardized by Congress was the chain.
The larger result was that Jefferson's system was made obsolete and never taken up again. It also established the tradition of Congress standardizing weights and measures in an ad hoc, non-systematic way.
I originally learned about all this in Andro Linklater's book "Measuring America". I don't think Linklater is a scholarly historian, and he might overstate the dramatic way Jefferson's system came so close to passing and how the Northwest Indian War undermined it. But the basic info should be good. Jefferson's proposal is here. Washington's urging of Congress can be found in his First-Third state of the union addresses. There's more info in "The Writings of Thomas Jefferson", Monticello Edition, Washington, D.C.: The Thomas Jefferson Memorial Association, 1904.
As a follow up question; how is it that some countries came to be using millilitres and others centilitres?
I'm from Australia where millilitres/litres is ubiquitous, but have been living in Germany the past few years where measuring liquids in centilitres is much more common. My swedish boyfriend also uses centilitres.