Why does the US use miles and feet to measure length?

The unit of measurement is an essential part of every area of ​​a country in general and everyone's life in particular. The unit of measurement plays an important role not only in scientific research but also for all other activities in human life.

>>>Table of measurement units of Anglo-American

In Vietnam, the unit of measurement is used uniformly according to SI international measurement standards. You use kilograms to calculate weight, liters to measure volume, . These are too familiar to each of us from high school to problems in daily life. But one day you watch the world market news on TV with the announcement that US oil prices are a gallon dollar. Surely you will wonder why Vietnam uses liters for gasoline, but the US market newsletter is measured in gallons? Not only the volume, but for many physical quantities, the US still uses many other units of measurement such as miles, feet, ounces, pounds, . to measure.

That's right, that's a fact that still exists today. So what is the cause of this?

The situation of using measurement units in countries around the world

A measurement system is a set of measurement units that can be used to measure any physical quantity. Length, mass and time are the most basic set of measurement units, from which many units can be deduced to measure other physical quantities. Historically, the measurement systems have been gradually formed according to local conventions to serve goods exchange, land measurement . During feudal times, the kings established the use of uniform measurement systems in the leadership. earth ruled.

When international trade becomes more prevalent, standard measurement systems for many countries are born. From the map using the above measurement system, currently, most of the countries in the world accept and use the system of measuring the international system (international measurement system, SI - International System of Units, in French Système International d'unités).

The true origin of the SI, or metric system, dates back to the 1640s. It was invented by French scientists and received great promotion by the French Revolution in 1789 to become more popular. The metric system has been developed since 1791 onwards because the Académie des sciences council used the principles of length, volume and volume proposed by missionary An John Wilkins in 1668.

The metric system tries to choose non-arbitrary units of measurement, while attached to the official ideology of revolution as "pure reason" . This is a significant improvement for the current units of measurement because their values ​​often depend on each region.

Besides, there are 3 regions in the world that have not yet applied international measurement system: America, Liberia and Myanmar. These three countries still use their own measurement system based on historical factors that still exist today. And one thing to mention is that changing the measurement system in a country is not simply a notice, a text, a law but also a lot of other obstacles.

Although the United States has set out a formal roadmap to apply an international measurement system throughout the territory, the situation of using units of measurement is still a lot of trouble. A simple example, an American football field is usually measured in yards while the track length is measured in meters. The power of some engines is usually measured by horsepower while others measure by cylinder capacity.

The above are just a few examples that show that the unit of measurement is a rather complex problem in the US. This is called the US Customary System or an inch-ounce system . Statistically, there are more than 300 units of measurement for many different physical quantities in the United States. Many of them have the same name but have different meanings. According to statistics, only 1 unit "ton" (tons) but there are 9 different meanings: short tons, long tons, displacement, tons of refrigeration, tons of nuclei, tons in shipping chemical, total registered loads, tons of tests and tons of coal equivalents.

So now we can divide the world into two parts: a large part is applying the SI measurement standard and the rest is currently applying its own measurement standards that represent the US. The first question will be transformed into: Why does the US not use the SI measurement system in both commercial and daily activities? To understand that, let us first look back at a brief piece of history how European metrology standards have come to America?

Historical measurement system in the US

In the process of American colonization and invasion by British colonialists, the Americans inherited and used the British Imperial System. This is a system that measures evolution from a series of complex measurement standards from the Middle Ages. Even when the French developed and perfected the metric system (metric system) from the late 1700s, the British and their colonies including the US still had to use an ancient measuring system.

Historically, American leadership lives have always wanted to control chaos in their unit of measurement. In the constitution constituting the United States, article I, section 8 stipulates that Congress has the right to correct standards of weight and measurement. The first person to enforce the problem was Thomas Jefferson, secretary of state under George Washington in 1790. Jefferson approved a decimal measurement system.

List of some units of measurement in the US in the early 19th century

However, when presenting the basic principles of the metric-based decimal system, Jefferson felt that applying this to the country was quite reluctant. He feared that the United States would not be able to verify the metric system and cost money to hire French helpers.

The political situation at that time in the US did not help solve the problem. Although the French had a lot of help for the US to revolutionize, their relationship became hostile after the treaty Jay was ratified in 1795. The Treaty of Jay allowed him to control the territory Northwest and the United States have some rights to trade in the West Indies (regions of the Caribbean Basin and the North Atlantic). For the French, this is a budding alliance between Anglo-American and French.

At that time, the French retaliated by sending search ships aimed at American merchant ships. When John Adams became US president in 1797, the hostility between the US and France became increasingly serious. Not long afterwards, in 1798, France further demonstrated its hostility by humiliating America by inviting dignitaries from other countries to Paris to study the metric system.

Although the American representatives also came to Paris in 1798 and were impressed by the advantages of the metric system, this was not enough to persuade US leaders to change the current measurement system. their. In 1821, after studying the use of measurement units in 22 states in the United States, Secretary of State John Quincy Adams found that the American-style measurement system was sufficiently consistent and not necessary to replace change. In addition, some comments in the United States also suggested that France's meter system would soon receive a tragic ending as the death of Napoleon Bonaparte dynasty in the early 19th century.

However, according to the flow of history, the metric system gradually became widely accepted and accepted by many countries around the world. The advantage of using this system is that it is easy to communicate data around the world, easily transforming magnitude based on multiples and divisors of 10 instead of using specific numbers but hard to remember. And of course, Americans also realize this.

The US decided to recognize the metric system

Over time, the metric system is increasingly influencing countries around the world. When the American Civil War ended in 1865, most of Europe approved the use of a decimal-based measurement system and, of course, the United States also wanted to do this. In 1866, a law passed by the US Congress and formally approved by President Andrew Johnson states: the statute stipulates the use of the metric system in all contracts, transactions or crafts. proceedings throughout the United States.

At this time, France wanted all the leading countries in the world to build up a new version of the metric system together. And of course, America also received invitations and sent delegates to attend. All countries have agreed to sign the Treaty of the Meter, establishing an International Commission for Metrology to carry out the review and change of the world measurement system.

The treaty also stipulates the establishment of a laboratory at Sèvres near Paris, to store international metric measurement standards such as international meters and distribute them to user countries.

The platinum plaque image of the X section to test the international meter

The US received a copy of the international meter form and an international kilogram model in 1890. Three years later in 1890, US finance minister Thomas Corwin Mendenhall formally set the standards for measuring length and weight at The US uses the metric system through regulation named Mendenhall Order. A yard is defined as 1600/3937 meters and a pound weight is determined by 0.4535924277 kilograms. In 1959, English-speaking countries accepted a new and improved conversion convention: 1 yard equals 0.9144 meters and 1 pound equals exactly 0.45359237 kilograms.

Read here, you might ask: why has the US officially switched to metric systems more than 120 years ago but still exists other units? Your questions will be answered in the next section: accreditation does not necessarily have to be applied to use.

Current measurement system in the US

Mendenhall and many political leaders and scientists supported the mandatory application of a metric system across the United States. However, until Mendenhall died in 1924, there were no changes in the US metrology.

By 1971, the US Bureau of National Standards issued a report titled "A US metrology standard" to recommend switching to the US metric system over the next 10 years. In response, the US Congress enacted a law requiring conversion to a metric system. However, instead of stipulating a 10-year transfer, Congress's law allows for a voluntary conversion.

However, all students across the United States began to study metric units seriously and some companies also switched to using metric units. However, these are just the first steps in making changes to the metric system in the US.

Meanwhile, the process of globalization is increasingly strong, companies in the United States began to realize that they are different from the relationships in the international arena. More and more foreign companies buy products from the US and they require delivery, labeling and production in metric units. In addition, when US companies build new factories in Europe and Asia, they face differences in American and international standard unit standards. This difference can cause companies huge financial consequences if the decision is wrong.

Recognizing this problem, in 1988, the US Congress passed the conversion of metering system data in the US to "the preferred measurement system for trade in the US" and also required The federal government must use the "metric system of units for distribution, subsidies and other business-related activities" by the end of 1992. However, this law continues to allow industries The private industry makes a transition to the metric system voluntarily and the federal government only encourages it, which is not compulsory. Therefore, the transition is quite slow.

According to some estimates, only about 30% of products manufactured in the US are compliant with metric units. Pharmaceutical companies use "hard metric systems" , which means that all of their products measure by metric system. On the other hand, the furniture industry uses both metric and American-style units for its products. This usage is called "flexible metric system". The film industry, tools and bicycles are also converted to metric units. However, most other industries do not use uniform metric units.

Why didn't most of the United States turn to using metric systems to integrate with the rest of the world? Find the reasons in the next section.

Switching to the metric system requires a lot of money?

The cost issue is one of the reasons for the slow transition to the US metric system. Converting technical drawings and guiding documents to operating complex devices can take thousands of hours. Typically engineers at NASA recently announced that the transfer of shuttle drawings, software and documents to the SI system could cost more than $ 370 million. This figure accounts for about half of the cost of making a full shuttle.

Of course, the cost issue is still not enough to explain the fact that the United States does not switch to metric. Besides costs, some psychological problems also have an important influence. The bigotry of the American people is also one of the causes of the problem. US citizens are always opposed to switching to metric systems, especially this transition is motivated by other countries.

Some psychological analysts argue that Americans simply like to do something different because individualism is always an inherent characteristic for every American. This ideology was formed by the first people who started exploring the wild America and created a united state with many hardships. An example of this is shown in the slogan of the American rifle association: "You can only get an inch-pound from my cold, dead hand."

However, the most rational and well-accepted explanation is that Congress has failed to apply the metric system in all 50 states and other territories. By allowing voluntary conversion under the 1866 Act, the United States did not restrict people to use units arbitrarily in their daily activities.

Until the entire United States has successfully converted to metric units, every American continues to think about inches and pounds instead of meters and kilograms to measure weight or length. Perhaps, in the future with a strong globalization trend and the emergence of other major powers, the US may soon take tougher measures to ensure its competitiveness compared to other countries in the world. . For now, you can use the unit you like in the US - the country of the free goddess!

A little about the measurement system in the UK

In fact, the use of units in the UK has many similarities with the United States. Some people often refer to another measurement system, this person is Anglo-American. The measurement system in the UK was originally a combination of measurements of Romans, Carolignians and Saxons. This is the Imperial system of units precursor in 1824.

Since its inception, the British metrology system has undergone many laws to modify the calculation method and is supported by the government for all British territories and colonies. Even in 1875, the British refused to sign the treaty of transition to metric system, and three years later, they enacted laws prohibiting people from using metrics in commerce.

One bottle of milk in the UK with many types of measurement units

Until after the Second World War, the British still used their measurement system with yard yard and pound units to measure weight. However, after that, scientific researchers and a part of citizens had an idea to convert to metric system, but the government still tried to retain its unit tradition.

Even so, the trend of globalization does not leave anyone, including the United Kingdom. Finally, the transition to the metric system in the UK began in the mid-1960s. The conversion took place voluntarily and by 1985, many English units were voluntarily removed. abandoned at many retail business locations. Even so, some old units of measurement such as foot, inch, pound, ounce and gallon are still used at some retail points, traffic signs, .

Currently, although across the UK has officially switched to using metric systems, the use of units of measurement in everyday life still has some interesting issues. If you go to a store in the UK and ask to buy a cheese, you can buy 100 grams of cheese or 1/4 pound cheese, the seller is happy to sell it to you. Some retail agricultural products still have price lists in pounds and kilograms.

Besides, traffic signs are still measured in miles but the price of gasoline is calculated in pounds per pound. The performance of a car engine is measured in miles per gallon. Some people still use their feet to calculate their height. Computer monitors or TVs are still measured in inches, but some places in the UK have switched to centimeter use.

In the UK, if you study natural science subjects in the school, all units are SI units because this is an international standard for scientific calculation and can be easily converted. However, when mentioning the temperature in life is also an interesting point. The British weather news reports both in Celsius and Fahrenheit. But when people talk about the weather temperature, people tend to use Celsius when the temperature is cold but use F degrees. when the weather is warm.