Why do we use feet and inches, and why do eggs come in dozens?
Why do we use feet and inches, and why do eggs come in dozens? We basically use feet as measurements because everybody has feet, and eggs come in dozens because it is easier to divide them up.
Imperial measurements are slowly disappearing and being replaced by metric, which are easier to use and easier to calculate with. However, some countries stick to their imperial measurements. Of these measurements, the most common are feet and inches. To convert it into metric measurements, a foot is exactly 0.3048 meters. There are 12 inches in a foot, so an inch is 25.4 millimeters. Feet and inches are most commonly used in America because it was the system the British took with them. These measurements had been used in England since they were taken there by the Romans in the 1st century AD.
In ancient civilizations, measurements were basically done with things people had. Most people have fingers, most people have hands, and most people have feet. It is very natural that feet and hands should become measurements for things. In general, there is no problem with this, but if you are trying to standardize things, it can be tricky. The distance between cities would change depending on the size of someone’s feet and the amount of cloth you were sold for a certain amount of money would change depending on the size of the clerk’s hands.
The foot and the inch came into Britain from Rome. The Roman foot is slightly smaller than the modern foot. They broke their feet up into units of twelve and called each unit “uncia”, which means one twelfth. It came into English as “ynce” and became inch over time. It also became ounce as well, rather interestingly, because there are 16 ounces in a pound, not twelve. The Roman foot was also used to standardize their mile, which was 5,000 feet.
In England, weights and measurements were meant to be the same everywhere, but they tended not to be. The first attempt to standardize the system in England came with King Edward I in the late 13th century. The law was called the Statute of Ells and Perches. The smallest unit was the barleycorn, which was a corn of barley laid lengthways. (This is the unit we measure shoe sizes in). 3 barleycorns made an inch, 12 inches made a foot, 3 feet made a yard, 5.5 yards made a perch (also called a rod), and 40 rods made a furlong. (A furlong was the length of land an ox could plow before it had to stop.)
However, it was the Weights and Measures Act of 1593 that locked in all of these measurements properly. And these are the measurements that were carried across the Atlantic to the New World. The metric system was first adopted in France in 1790, and it slowly spread throughout Europe. In the new emerging fields of science, it was much easier to calculate with metric than with imperial. Britain stuck with imperial, but, recently, has been gradually trending towards metric in some areas. The USA, possibly because once a system is baked into construction, manufacturing, and everyday habits, changing it is expensive and slow, has stuck to imperial.
The reason eggs come in dozens is probably a little easier to understand than feet and inches. We have 12 eggs in a box for the same reason we have 24 hours in a day, 60 minutes in an hour, 60 seconds in a minute, and 360 degrees in a circle. It just makes calculations easier. A lot of this comes from the mathematics of the Sumerians, followed by the Babylonians, who used a base-60 system. These days, we work in base-10, which works well in the metric system. However, for dividing things up, base-60 is very convenient because it has far more factors. If you take the number 100, for example, you can only divide it evenly by 50, 20, 10, 5, 2, and 1. If you take the number 60, you can divide it by 30, 20, 15, 10, 6, 4, 3, 2, and 1. That’s far more. Days, hours, and circles can be split up far more easily with base-60, and dozens fit the same logic. If eggs are being sold or shipped, it is much easier to break up a box of 12 than a box of 10. The word “dozen” also comes through French from Latin roots meaning “twelve.” As an added benefit, there were 12 pennies in a British shilling, which made eggs easy to price as well. And this is what I learned today. Sources
https://newschoolmontessori.com/history-of-measurement
https://en.wikipedia.org/wiki/Foot_(unit)
https://en.wikipedia.org/wiki/Inch
https://en.wikipedia.org/wiki/Imperial_units
https://www.factmonster.com/math-science/weights-measures/origins-of-measurements
https://en.wikipedia.org/wiki/Weights_and_Measures_Acts_(UK)
https://en.wikipedia.org/wiki/Composition_of_Yards_and_Perches
https://www.thoughtco.com/why-we-still-use-babylonian-mathematics-116679
Photo by Leeloo The First: https://www.pexels.com/photo/brown-wooden-ruler-and-colored-pencils-on-papers-8970296/