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Walk This Way: The History of the Moving Sidewalk

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Getty Images

Authors like H.G. Wells, Isaac Asimov, and Robert Heinlein have long envisioned a future where the automobile gives way to massive, high-speed moving walkways. Some of them merely zoom commuters around cities, while others, like Heinlein’s "mechanized roads,” could take people from Cleveland all the way to Cincinnati.

The moving sidewalk is familiar to travelers in the real world, too, but smaller and limited to controlled environments like airports and train stations. They lack the grandeur and the game-changing status that futurists once envisioned, but that isn’t to say that people haven’t tried for larger, longer, faster moving sidewalks. Inventors had very real plans for the moving sidewalk that rivaled anything Wells dreamed up, but were undone by technical limitations and wary politicians and riders that science fiction authors could simply write their way around.

A Walking Tour of Moving Sidewalks

The history of real-world moving sidewalks goes back to a New Jersey inventor/wine merchant named Alfred Speer, who received the first patent for one in 1871. The first one operated in the U.S. was built for the 1893 World's Fair in Chicago. Operated by the Columbian Movable Sidewalk Company, which charged 5 cents for a ride, it ran almost the entire length of the 3,500-foot pier that many guests arrived at after taking a scenic steamship trip from downtown to the fairgrounds. Riders could stand or walk on the first platform, which traveled at about two miles per hour, or step up onto a second parallel platform, which ran at four miles per hour and had benches. Running at full capacity, the walkway could ferry 31,680 passengers per hour. Its life was short, though, and it was destroyed by a fire the following year.

The wooden moving pavement ('Trottoir Roulant') at the Exposition Universal in Paris, 1900 /

In the early years of the next century, Speer and Max Schmidt, who designed a moving walkway for the 1900 Exposition Universal in Paris, both proposed their own versions of the moving sidewalk in Manhattan to relieve some of the foot traffic on New York City’s crowded streets. Speer’s plan called for an elevated system of three parallel walkways running along Broadway that would move passengers at up to 19 mph. Speer’s system had one stationary platform for boarding and two moving ones where riders could either stand, walk or even have a seat in one of a few enclosed “parlor cars” that had drawing rooms for ladies, and space for men to sit and smoke. Despite building a working model and finding support in the city government and state legislature, Speer’s project was repeatedly killed by the governor.

Schmidt’s vision for a Brooklyn Bridge moving walkway consisted of a loop system with four platforms, one for boarding and three others that moved at increasing speeds, the fastest of which ran at 10 mph. Schmidt planned for the system to run constantly, so passengers wouldn’t have to wait to board and no momentum would be lost on stopping and starting the platforms. Schmidt and the individuals and groups who proposed similar systems in Atlanta, Boston, Los Angeles, Detroit, and Washington, D.C., all eventually saw their plans crumble under their own novelty. Maintenance and breakdown concerns, the question of what passengers were supposed to do in the rain or snow, and the familiarity and reliability of buses and subway trains all helped doom the urban moving sidewalk.

Let’s Try This Again

A half-century later, the moving sidewalk reared its head again when smaller-scale versions showed up in sprawling airports and train stations. They’re hardly the stuff of Wells and Schmidt, and are usually just a single platform moving slowly from Point A to Point B just a few hundred yards away.

The first of these simpler sidewalks got moving in May 1954 at the Hudson and Manhattan Railroad’s Erie station in Jersey City, NJ. Built by the Goodyear Tire and Rubber Co., the “Speedwalk’s” 5½-ft wide platform ran 277 feet up an incline used to exit the station, at a top speed of 1.5 mph. It was a relief to many riders used walking up the exit hall, which had earned the nickname “Cardiac Alley.”

While the Speedwalk might have prevented a few injuries, the first moving sidewalk installed at an airport - at Love Field in Dallas in 1958 - infamously caused several. One person was even killed. Early in the sidewalk’s operation, several people got clothing or a foot stuck where the conveyor met solid ground and disappeared into the floor to loop back. A dog suffered a broken leg. A seven-year-old boy got his t-shirt and hand sucked in and lost most of the skin on his fingers. As the boy’s mother tried to free him, her clothing got caught too, and her skirt and slip were pulled clean off. She continued to struggle with her son in nothing but a leather coat until the machine was turned off.

Two years later, an accident resulted in death. On New Year’s Day in 1960, a two-year-old girl, fascinated by the moving sidewalk, broke away from her mother and waddled over for a closer look. Her coat sleeve got caught at the edge, and her left hand, wrist and forearm were pulled below the floor. A police officer rushed to cut off her clothes to release her. He later told newspapers that her coat was pulled so tight around her chest that he couldn’t even get his knife underneath it.

Not So Fast

Designs and safety measures for the moving sidewalk improved, and its use spread to most airports over the next few decades. Some engineers even took another stab at larger, faster versions. Prototype high-speed walkways have been tried out in Paris metro stations in the 1980s and the early 2000s, but both systems were shut down due to mechanical complexity, unreliability, and passenger accidents.

While the idea of quickly floating over the Brooklyn Bridge or across Ohio on a moving walkway is exciting, there seems to be a practical limit to how fast a person can travel on a moving platform without losing their balance and toppling over. Fast, car-less travel over great distances is maybe best left to airplanes and high-speed rail lines. For the shorter moving sidewalks we have now, we don’t necessarily need speed and all the mechanical and safety problems that go with it.

The airport moving sidewalks often slow us down, versus walking normally, because people stand around or block the platform with their bags. The future of the people mover, perhaps, isn’t in a mechanical road that takes us from one town to another, but just an airport moving walkway that isn't treated like a leisure cruise. As Jerry Seinfeld used to say, "It's not a ride!"

Today's Wine Glasses Are Almost Seven Times Larger Than They Were in 1700

Holiday party season (a.k.a. hangover season) is in full swing. While you likely have no one to blame but yourself for drinking that second (or third) pour at the office soiree, your glassware isn't doing you any favors—especially if you live in the UK. Vino vessels in England are nearly seven times larger today than they were in 1700, according to a new study spotted by Live Science. These findings were recently published in the English medical journal The BMJ.

Researchers at the University of Cambridge measured more than 400 wineglasses from the past three centuries to gauge whether glass size affects how much we drink. They dug deep into the history of parties past, perusing both the collections of the Ashmolean Museum of Art and Archaeology at the University of Oxford and the Royal Household's assemblage of glassware (a new set is commissioned for each monarch). They also scoured a vintage catalog, a modern department store, and eBay for examples.

After measuring these cups, researchers concluded that the average wineglass in 1700 held just 2.2 fluid ounces. For comparison's sake, that's the size of a double shot at a bar. Glasses today hold an average of 15.2 fluid ounces, even though a standard single serving size of wine is just 5 ounces.

BMJ infographic detailing increases in wine glass size from 1700 to 2017
BMJ Publishing group Ltd.

Advances in technology and manufacturing are partly to blame for this increase, as is the wine industry. Marketing campaigns promoted the beverage as it increasingly became more affordable and available for purchase, which in turn prompted aficionados to opt for larger pours. Perhaps not surprisingly, this bigger-is-better mindset was also compounded by American drinking habits: Extra-large wineglasses became popular in the U.S. in the 1990s, prompting overseas manufacturers to follow suit.

Wine consumption in both England and America has risen dramatically since the 1960s [PDF]. Cambridge researchers noted that their study doesn't necessarily prove that the rise of super-sized glassware has led to this increase. But their findings do fit a larger trend: previous studies have found that larger plate size can increase food consumption. This might be because they skew our sense of perception, making us think we're consuming less than we actually are. And in the case of wine, in particular, oversized glasses could also heighten our sensory enjoyment, as they might release more of the drink's aroma.

“We cannot infer that the increase in glass size and the rise in wine consumption in England are causally linked,” the study's authors wrote. “Nor can we infer that reducing glass size would cut drinking. Our observation of increasing size does, however, draw attention to wine glass size as an area to investigate further in the context of population health.”

[h/t Live Science]

Researchers Pore Over the Physics Behind the Layered Latte

The layered latte isn't the most widely known espresso drink on coffee-shop menus, but it is a scientific curiosity. Instead of a traditional latte, where steamed milk is poured into a shot (or several) of espresso, the layered latte is made by pouring the espresso into a glass of hot milk. The result is an Instagram-friendly drink that features a gradient of milky coffee colors from pure white on the bottom to dark brown on the top. The effect is odd enough that Princeton University researchers decided to explore the fluid dynamics that make it happen, as The New York Times reports.

In a new study in Nature Communications, Princeton engineering professor Howard Stone and his team explore just what creates the distinct horizontal layers pattern of layered latte. To find out, they injected warm, dyed water into a tank filled with warm salt water, mimicking the process of pouring low-density espresso into higher-density steamed milk.

Four different images of a latte forming layers over time
Xue et al., Nature Communications (2017)

According to the study, the layered look of the latte forms over the course of minutes, and can last for "tens of minutes, or even several hours" if the drink isn't stirred. When the espresso-like dyed water was injected into the salt brine, the downward jet of the dyed water floated up to the top of the tank, because the buoyant force of the low-density liquid encountering the higher-density brine forced it upward. The layers become more visible when the hot drink cools down.

The New York Times explains it succinctly:

When the liquids try to mix, layered patterns form as gradients in temperature cause a portion of the liquid to heat up, become lighter and rise, while another, denser portion sinks. This gives rise to convection cells that trap mixtures of similar densities within layers.

This structure can withstand gentle movement, such as a light stirring or sipping, and can stay stable for as long as a day or more. The layers don't disappear until the liquids cool down to room temperature.

But before you go trying to experiment with layering your own lattes, know that it can be trickier than the study—which refers to the process as "haphazardly pouring espresso into a glass of warm milk"—makes it sound. You may need to experiment several times with the speed and height of your pour and the ratio of espresso to milk before you get the look just right.

[h/t The New York Times]


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