A Step Back in Time: The Origins of Body-Based Measurements
Imagine a world before rulers, yardsticks, or measuring tapes. In ancient times, when people wanted to measure something, they turned to the most accessible “tools” they had: their own bodies! And so, body-based measurement units were born, weaving human anatomy into the fabric of math and science.
The “Foot” and King Henry I
The “foot” is one of the oldest body-based measurements, and according to legend, it may have been standardized by none other than King Henry I of England in the 12th century. Supposedly, he declared that one foot should equal the length of his own — about 12 inches. This royal decree gave a new “foot-hold” to a measurement that had been used in various forms by the Egyptians, Mesopotamians, and many others.
Body-Based Measurements Across Cultures
Around the world, societies developed their own ways to measure based on the human body. These units were practical for everyday tasks like building, farming, and trading, where perfection wasn’t always necessary:
- Cubit: From the elbow to the tip of the middle finger, used by the Egyptians, measuring around 18 inches.
- Span: The width of a hand with fingers spread, about 9 inches, commonly used in ancient Greece and Rome.
- Inch: The Romans defined it as the width of a thumb. Its name comes from the Latin uncia, meaning “one-twelfth,” as it was one-twelfth of a Roman foot.
- Yard: Another “tall tale” suggests that King Henry I declared a yard should be the distance from his nose to the tip of his thumb with his arm extended — a royal yardstick, quite literally!
Even without exact tools, these measurements served their purpose well. Each civilization found ways to use the human body to measure distance, area, and more — laying a groundwork for the systems we use today.
Legendary (and Quirky) Units in Real Life
Some body-based measurements have become famous for their quirks and creativity:
- The Smoot: In 1958, an MIT student named Oliver Smoot was laid end-to-end to measure the Harvard Bridge in Boston. At 5 feet 7 inches tall, he became an informal unit of length: one Harvard Bridge is 364.4 Smoots (plus or minus an ear). The Smoot is still humorously used as a measurement around MIT and Harvard. [BOSTON HIDDEN GEMS]
- Beard-Second: A humorous unit of length used by physicists, representing the distance a beard hair grows in one second — approximately 5 nanometers. It’s a fun reminder of the playfulness in science, even when discussing precise measurements.
From Tradition to Precision
With the rise of global trade and the need for precision, different lengths for feet, inches, and other body-based units led to confusion. During the 18th and 19th centuries, countries began standardizing measurements. This led to definitions based on physical prototypes and scientific constants: the foot became exactly 12 inches or 30.48 centimeters, and the yard was set at 3 feet or 0.9144 meters.
Body-Based Units in Modern Society
Today, while we rely on digital tools and the metric system, body-based measurements still show up in informal ways:
- People might say, “It’s about a foot long.” or “It’s only a stone’s throw away.”
- In the equestrian world, horses are still measured in “hands,” where one hand equals 4 inches.
Even as science and technology advance, body-based measurements linger in our language and culture, reminding us of simpler times when a foot or a hand was all you needed to make sense of the world.
From the royal foot of King Henry I to the Smoots of Harvard Bridge, body-based measurements take us on a fascinating journey through history. They connect us to our past, adding a touch of human creativity to the world of measurement. Next time you hear someone talk about a “yardstick” or something being a “foot away,” remember — these are more than just numbers; they’re stories of our shared human experience.