The Reason Why Stop Signs Are Red

Roman_Gorielov, iStock/Getty Images Plus
Roman_Gorielov, iStock/Getty Images Plus

Why is red the standard color for stop signs? The short answer is this: because the representatives of the First National Conference on Street and Highway Safety in 1924 decided so.

Though stop signs were still a relatively new idea in the United States back in the 1920s—Detroit erected the first one around 1915, Jalopnik reports—the “red means ‘stop’” custom dates back to 1841, when Henry Booth of the Liverpool and Manchester Railway suggested using red to indicate danger on railroads. London then adopted the color for its regular traffic lights in 1868, and the United States eventually followed suit.

The First National Conference on Street and Highway Safety, called by then-Secretary of Commerce Herbert Hoover in 1924, aimed to standardize the color coding of road signage. It established that for all “signs and signals, both luminous and nonluminous,” red should indicate “stop,” green should indicate “proceed,” and yellow should indicate “caution,” according to the report released after the conference [PDF]. It was also decided that distance and direction signs should be black and white.

That all probably sounds familiar if you’ve ever seen a street before, but implementing the mandate for red stop signs posed immediate issues. A red material that wouldn’t fade over time just didn’t exist in 1924, Gene Hawkins, a professor of civil engineering at Texas A&M University, told The New York Times in 2011. So the writers of the 1935 Manual on Uniform Traffic Control Devices chose the next best thing: yellow. The manual also specified that every sign should be octagonal, another idea from the 1920s.

California was first to figure out that porcelain enamel would resist fading and erect red stop signs across the state, a practice noticed and addressed in the 1954 revision [PDF] to the Manual on Uniform Traffic Control Devices. Now that red was more logistically feasible, the committee in charge of updating the manual decided there should be no more yellow stop signs.

We don’t know exactly why Henry Booth and other early industrialists felt that red aptly signaled “stop.” Maybe they thought it was harder to overlook than blue or green, which natural surroundings like water and foliage might easily camouflage. Maybe they felt red, like fire or blood, just went along well with danger.

There may also be a deeper reason. When, as part of a 2011 study, red-, blue-, and green-clad human experimenters offered apple slices to individual monkeys in a free-range facility, the monkeys seemed to have an aversion to taking slices left by the experimenter wearing red. Perhaps our association of danger with the color red has a psychological basis we don’t fully understand yet.

[h/t Jalopnik]

The Ingenious Reason Medieval Castle Staircases Were Built Clockwise

Shaiith/iStock via Getty Images
Shaiith/iStock via Getty Images

If you’re a fan of Game of Thrones or medieval programs in general, you’re probably familiar with action-packed battle scenes during which soldiers storm castles, dodge arrows, and dash up spiral staircases. And, while those spiral staircases might not necessarily ascend clockwise in every television show or movie you’ve watched, they usually did in real life.

According to Nerdist, medieval architects built staircases to wrap around in a clockwise direction in order to disadvantage any enemies who might climb them. Since most soldiers wielded swords in their right hands, this meant that their swings would be inhibited by the inner wall, and they’d have to round each curve before striking—fully exposing themselves in the process.

Just as the clockwise spiral hindered attackers, so, too, did it favor the castle’s defenders. As they descended, they could swing their swords in arcs that matched the curve of the outer wall, and use the inner wall as a partial shield. And, because the outer wall runs along the wider edge of the stairs, there was also more room for defenders to swing. So, if you’re planning on storming a medieval castle any time soon, you should try to recruit as many left-handed soldiers as possible. And if you’re defending one, it’s best to station your lefties on crossbow duty and leave the tower-defending to the righties.

On his blog All Things Medieval, Will Kalif explains that the individual stairs themselves provided another useful advantage to protectors of the realm. Because the individual steps weren’t all designed with the same specifications, it made for much more uneven staircases than what we see today. This wouldn’t impede the defenders, having grown accustomed to the inconsistencies of the staircases in their home castle, but it could definitely trip up the attackers. Plus, going down a set of stairs is always less labor-intensive than going up.

Staircase construction and battle tactics are far from the only things that have changed since the Middle Ages. Back then, people even walked differently than we do—find out how (and why) here.

[h/t Nerdist]

The Reason Queen Elizabeth II Demands Her Ice Cubes Be Round

The Queen makes a toast with King Willem-Alexander of The Netherlands during a State Banquet at Buckingham Palace in October 2018.
The Queen makes a toast with King Willem-Alexander of The Netherlands during a State Banquet at Buckingham Palace in October 2018.
Yui Mok, WPA Pool/Getty Images

Whether you prefer it crushed, cubed, or cylindrical (complete with a straw-sized hole through the center), you probably have an opinion about which type of ice is the best. As it turns out, so does Queen Elizabeth II.

According to The Independent, the 93-year-old monarch requests that her drinks contain round ice, rather than the more traditional cubes. As Karen Dolby, author of the upcoming Queen Elizabeth II’s Guide to Life, told The Sun, the reason is because balls of ice don’t clink quite as much in the glass—possibly because spheres have smaller surface areas than cubes for any given volume.

Dolby also revealed that the Queen’s ice specifications don’t just apply to her own beverages; she insists that all drinks in her residences be served with round ice. We don’t know for sure if that included the private staff bar that used to be located in Buckingham Palace, but it definitely wasn’t shut down because of a few loud ice cubes.

While promoting his book We Are Amused in 2010, unofficial royal biographer Brian Hoey told ABC News that the Queen detests the noise of ice clinking so much that Prince Philip actually created an ice machine to produce tiny, quieter balls of ice, though that hasn’t been confirmed by any official royal sources.

The Queen might not need ice at all for several beverages she’s been known to enjoy, including tea, champagne, and wine, but she does need it for her drink of choice—gin mixed with Dubonnet, which she prefers on the rocks.

Wondering what else you don’t know about the long-reigning Queen of England? Find out 25 more fascinating facts here.

[h/t The Independent]

SECTIONS

arrow
LIVE SMARTER