Why is a Famous American Bridge Officially Measured in Smoots? The Strange Tale of a Human Unit of Measurement

What if the mile was replaced by the length of a thousand people lying end-to-end? It sounds like a measurement from a fairy tale, but on one famous American bridge, a unit of measurement based on a human’s height isn’t just a quirky tradition—it’s an officially recognized part of the landmark. The bridge in question is the Harvard Bridge, connecting Boston and Cambridge, Massachusetts, and its unique unit is the "Smoot." This post delves into the bizarre and fascinating story of how a college prank evolved into a semi-official unit of length, forever cemented into the city's infrastructure and culture.

The Bridge, The Man, and The Prank

The story begins in October 1958 with a fraternity pledge class at the Massachusetts Institute of Technology (MIT). As part of their initiation into the Lambda Chi Alpha fraternity, the pledges were tasked with measuring the length of the Harvard Bridge. But they couldn't use a tape measure. Instead, they had to use one of their own pledges as a human ruler.

The pledge chosen for this task was the 5-foot-7-inch Oliver R. Smoot. His fraternity brothers repeatedly picked him up and laid him down end-to-end across the entire length of the bridge, making a paint mark at the end of his head each time. The arduous process concluded with a final measurement: the bridge was 364.4 Smoots, "plus or minus one ear"—a humorous nod to the imprecision of their method. The "Smoot" was born.

From College Shenanigans to Official Marker

What started as a one-off prank could have easily faded into obscurity. However, the Lambda Chi Alpha fraternity made it a tradition to repaint the Smoot markings on the bridge each year, keeping the legacy alive. The measurement became a beloved piece of local lore, but its leap to "official" status is what makes the story truly remarkable.

During major renovations to the bridge in the 1980s, the Massachusetts Metropolitan District Commission, the agency in charge of the project, made a surprising decision. They instructed the construction company to preserve the Smoot markings. The markings had become so ingrained in local culture that they were deemed an essential feature of the bridge.

The official recognition went even further:

• Police Usage: The Cambridge Police Department began using the Smoot marks as reference points to identify the location of accidents on the bridge.
• Structural Integration: The new concrete sidewalk slabs installed during the renovation were cut to a length of 5 feet 7 inches—the exact length of one Smoot.
• Digital Recognition: In the modern era, you can even use the Smoot as a unit of measurement in Google Earth and Google Maps, solidifying its status as a recognized, albeit unconventional, unit.

The Ultimate Irony: Mr. Smoot and The World of Standards

Perhaps the most incredible twist in this story is the later career of Oliver R. Smoot himself. The man who became an arbitrary, non-standard unit of measurement went on to have a highly distinguished career in the world of... well, standards.

Smoot eventually became the Chairman of the American National Standards Institute (ANSI), the body that oversees the development of consensus standards for products and services in the United States. If that wasn't ironic enough, he later served as the President of the International Organization for Standardization (ISO), the global body that sets industrial and commercial standards worldwide. The man famous for being an ad-hoc ruler became the world's leading advocate for standardized measurement.

Conclusion

The story of the Smoot is a perfect example of how tradition and human ingenuity can leave a permanent mark on our public spaces. What began as a silly fraternity prank has evolved into a functional, officially recognized, and cherished feature of the Harvard Bridge. It serves as a lasting tribute to student life and a reminder that sometimes the most unconventional ideas are the ones that stick. So, the next time you hear about a strange local custom, remember Oliver Smoot—a man who proves that you can make your mark on the world, one body length at a time.