What’s the Purpose of the Dots on a Basketball?


To reveal just why and how those little speckles made their way to your basketball, we’ll need to take a trip back to the early days of the sport, dabble in a little bit of physics, and swing on over to the leather company which makes those dots possible.

Physics and the Early Anatomy of a Basketball

Ever tried to grab a handful of ice cubes, only to have them all slip out of your hands?

This is a consequence of an absence of friction. When two forces smash together, friction is the force that breaks up, slows down, or otherwise alters that movement. The more points of contact an object has with a surface, the more friction it has. It’s what makes concrete pebbles easy to run on and those traction marks on your snow boots work against the ice to keep you from flip-flopping on your bum.

Without much friction, things get slippery. In the ice cube example, those slippery cubes, with their sleek, non-resistant surfaces, combined with your undoubtedly well-moisturized hands, have few points of contact upon which to create friction. In line with Newton’s First Law of Motion, the ice cubes then freely exercise their right to be objects in motion that stay in motion and, thus, slip out of your hands and scatter all across your kitchen floor.

Such a diminished level of friction is beneficial in some sports. It’s what makes bowling balls glide down the lane and adds fluidity to Sasha Cohen’s figure skating routines. But for basketballs? Friction-less balls would scatter about like so many large, bounce-able marbles.

And that’s exactly what the early basketballs were doing all across the court in 1894. At the time, teams were using soccer balls. The slick surface of the soccer ball, combined with the oil-polished hardwood gym floors, created a slip-and-slide during game time. Players became less concerned about the purpose of the game (making baskets) and more concerned about just trying to hold on to the ball.

Fortunately, James Naismith, the charming, well-mustachioed P.E. teacher who invented the game back in 1891, was not about to let a soccer ball get in the way of his legacy. Naismith called forth his good buddy and sporting goods maker, A.G. Spalding, and the two collaborated on a design for a new ball that would enhance the players’ ability to handle it. They decided that the ball not only had to be larger, but it also needed an added source of friction.

This is where the dots come in.

The dots, combined with a rough, well-treated leather, would create more points of contact with the court and enhance the amount of friction over the ball. Thus, the first pebbled Spalding basketball was born, and the players celebrated: they could dribble the ball and it wouldn’t go flying out of their hands. It was a miracle of innovation, and one that sticks to this day.

The dots today

The dots (or “pebbles” as they’re known in the basketball-making trade) are all over basketballs today, and the Horween Leather Company has been manufacturing the NBA’s speckled leather for over 60 years.

Having started its foray into tanning back in 1905, Horween Leather nudged its way into the sports trade through its founders’ love of football. One of the company’s founders, Arnold Horween Sr., had a strong history with the Harvard football team. Horween got him in touch with George Halas, the founder of the Chicago Bears, who then hooked Horween up with the Chicago-based Wilson football company. From then on, it was football-making destiny.

At the time of Wilson and Horween’s collaboration, Spalding was using an alternate leather tanning company to produce its basketball leather, but when that leather company fell to bankruptcy, Spalding found itself looking for a new source of horsehide. Noting Horween’s reputation for quality NFL products, Spalding made the leap over to Horween. It paid off: Horween stands strong as not only the maker of all NFL and NBA game balls, but also as the only tanning company surviving in all of Chicago.

Horween’s process of making that special NBA-certified leather is no easy bag of chips. It involves inspecting, baiting, pickling, tanning, re-tanning “in tack” (i.e.: adding essential oils to make the leather stickier and easier to grip), drying, and grading all the horsehide leather. At the end of its long journey, the leather is taken to a special press, where dots are embossed to create each individual pebble. Both basketballs and footballs get the exact same pebbling embossment (with the exception of Wilson-brand products, which has its own special mold).

While the extra points of contact provided by those tack-covered pebbles do wonders for a modern basketball, those speckles can’t completely prevent the ball slipping from your hands. When you play basketball, you sweat, and when you sweat, things get slippery, which can cause your high-quality basketball to slip straight out of your hands.

No shame! Even Michael Jordan got sweaty palms. While nothing can 100% insure that you keep your mighty grip on the ball at all times, a little human intervention can better prepare your ball for game play. If you have a fairly new ball, consider breaking it in by playing a few practice games ahead of time. The contact of the ball with a surface, like, say, concrete (a surface ripe with friction-friendly pebbles), creates a more rugged terrain on your ball. The more pebbled your leather, the better the traction. The better the traction, the easier the ball is to handle. The easier the ball is to handle, the more likely you are to win that game of HORSE with your neighbor (depending who your neighbor is).

Big Questions
Why Do Onions Make You Cry?

The onion has been traced back as far as the Bronze Age and was worshipped by the Ancient Egyptians (and eaten by the Israelites during their bondage in Egypt). Onions were rubbed over the muscles of Roman gladiators, used to pay rent in the Middle Ages, and eventually brought to the Americas, where today we fry, caramelize, pickle, grill, and generally enjoy them.

Many of us burst into tears when we cut into one, too. It's the price we pay for onion-y goodness. Here's a play-by-play breakdown of how we go from grabbing a knife to crying like a baby:

1. When you cut into an onion, its ruptured cells release all sorts of goodies, like allinase enzymes and amino acid sulfoxides. The former breaks the latter down into sulfenic acids.

2. The sulfenic acids, unstable bunch that they are, spontaneously rearrange into thiosulfinates, which produce a pungent odor and at one time got the blame for our tears. The acids are also converted by the LF-synthase enzyme into a gas called syn-propanethial-S-oxide, also known as the lachrymatory factor (or the crying factor).

3. Syn-propanethial-S-oxide moves through the air and reaches our eyes. The first part of the eye it meets, the cornea, is populated by autonomic motor fibers that lead to the lachrymal glands. When syn-propanethial-S-oxide is detected, all the fibers in the cornea start firing and tell the lachrymal glands to wash the irritant away.

4. Our eyes automatically start blinking and producing tears, which flushes the irritant away. Of course, our reaction to burning eyes is often to rub them, which only makes things worse since our hands also have some syn-propanethial-S-oxide on them.

It only takes about 30 seconds to start crying after you make the first cut; that's the time needed for syn-propanethial-S-oxide formation to peak.


The onion's relatives, like green onions, shallots, leeks and garlic, also produce sulfenic acids when cut, but they generally have fewer (or no) LF-synthase enzymes and don't produce syn-propanethial-S-oxide.


Since I usually go through a good deal of onions while cooking at home, I've been road testing some of the different methods the internet suggests for reducing or avoiding the effects of the lachrymatory factor. Here's what I tried:

Method #1: Chill or slightly freeze the onions before cutting, the idea being that this will change the chemical reactions and reduce the gas that is released.
Result: The onion from the fridge has me crying just as quickly as room temperature ones. The one that was in a freezer for 30 minutes leaves me dry-eyed for a bit, but by the time I'm done dicing my eyes start to burn a little.

Method #2: Cut fast! Get the chopping over with before the gas reaches your eyes.
Result: Just hacking away at the onion, I get in the frying pan without so much as a sting in my eyes. The onion looks awful, though. Doing a proper dice, I take a little too long and start tearing up. If you don't mind a mangled onion, this is the way to go.

Method #3: Put a slice of bread in your mouth, and cut the onion with most of the bread sticking out to "catch" the fumes.
Result: It seems the loaf of bread I have has gone stale. I stop the experiment and put bread on my shopping list.

Method #4: Chew gum while chopping. It keeps you breathing through your mouth, which keeps the fumes away from your eyes.
Result: This seems to work pretty well as long as you hold your head in the right position. Leaning toward the cutting board or looking right down at the onion puts your eyes right in the line of fire again.

Method #5: Cut the onions under running water. This prevents the gas from traveling up into the eyes.
Result: An onion in the sink is a hard onion to cut. I think Confucius said that. My leaky Brita filter is spraying me in the face and I'm terrified I'm going to cut myself, but I'm certainly not crying.

Method #6: Wear goggles.
Result: In an effort to maintain my dignity, I try my eyeglasses and sunglasses first. Neither do me any good. The ol' chemistry lab safety glasses make me look silly, but help a little more. I imagine swim goggles would really do the trick, but I don't have any.

Method #7: Change your onion. "Tear free" onions have been developed in the UK via special breeding and in New Zealand via "gene silencing" techniques.
Result: My nearest grocery store, Whole Foods, doesn't sell genetically modified produce or onions from England. Tonight, we eat leeks!

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Big Questions
What is Mercury in Retrograde, and Why Do We Blame Things On It?

Crashed computers, missed flights, tensions in your workplace—a person who subscribes to astrology would tell you to expect all this chaos and more when Mercury starts retrograding for the first time this year on Friday, March 23. But according to an astronomer, this common celestial phenomenon is no reason to stay cooped up at home for weeks at a time.

"We don't know of any physical mechanism that would cause things like power outages or personality changes in people," Dr. Mark Hammergren, an astronomer at Chicago's Adler Planetarium, tells Mental Floss. So if Mercury doesn’t throw business dealings and relationships out of whack when it appears to change direction in the sky, why are so many people convinced that it does?


Mercury retrograde—as it's technically called—was being written about in astrology circles as far back as the mid-18th century. The event was noted in British agricultural almanacs of the time, which farmers would read to sync their planting schedules to the patterns of the stars. During the spiritualism craze of the Victorian era, interest in astrology boomed, with many believing that the stars affected the Earth in a variety of (often inconvenient) ways. Late 19th-century publications like The Astrologer’s Magazine and The Science of the Stars connected Mercury retrograde with heavy rainfall. Characterizations of the happening as an "ill omen" also appeared in a handful of articles during that period, but its association with outright disaster wasn’t as prevalent then as it is today.

While other spiritualist hobbies like séances and crystal gazing gradually faded, astrology grew even more popular. By the 1970s, horoscopes were a newspaper mainstay and Mercury retrograde was a recurring player. Because the Roman god Mercury was said to govern travel, commerce, financial wealth, and communication, in astrological circles, Mercury the planet became linked to those matters as well.

"Don’t start anything when Mercury is retrograde," an April 1979 issue of The Baltimore Sun instructed its readers. "A large communications organization notes that magnetic storms, disrupting messages, are prolonged when Mercury appears to be going backwards. Mercury, of course, is the planet associated with communication." The power attributed to the event has become so overblown that today it's blamed for everything from digestive problems to broken washing machines.


Though hysteria around Mercury retrograde is stronger than ever, there's still zero evidence that it's something we should worry about. Even the flimsiest explanations, like the idea that the gravitational pull from Mercury influences the water in our bodies in the same way that the moon controls the tides, are easily deflated by science. "A car 20 feet away from you will exert a stronger pull of gravity than the planet Mercury does," Dr. Hammergren says.

To understand how little Mercury retrograde impacts life on Earth, it helps to learn the physical process behind the phenomenon. When the planet nearest to the Sun is retrograde, it appears to move "backwards" (east to west rather than west to east) across the sky. This apparent reversal in Mercury's orbit is actually just an illusion to the people viewing it from Earth. Picture Mercury and Earth circling the Sun like cars on a racetrack. A year on Mercury is shorter than a year on Earth (88 Earth days compared to 365), which means Mercury experiences four years in the time it takes us to finish one solar loop.

When the planets are next to one another on the same side of the Sun, Mercury looks like it's moving east to those of us on Earth. But when Mercury overtakes Earth and continues its orbit, its straight trajectory seems to change course. According to Dr. Hammergren, it's just a trick of perspective. "Same thing if you were passing a car on a highway, maybe going a little bit faster than they are," he says. "They're not really going backwards, they just appear to be going backwards relative to your motion."

Embedded from GIFY

Earth's orbit isn't identical to that of any other planet in the solar system, which means that all the planets appear to move backwards at varying points in time. Planets farther from the Sun than Earth have even more noticeable retrograde patterns because they're visible at night. But thanks to astrology, it's Mercury's retrograde motion that incites dread every few months.

Dr. Hammergren blames the superstition attached to Mercury, and astrology as a whole, on confirmation bias: "[Believers] will say, 'Aha! See, there's a shake-up in my workplace because Mercury's retrograde.'" He urges people to review the past year and see if the periods of their lives when Mercury was retrograde were especially catastrophic. They'll likely find that misinterpreted messages and technical problems are fairly common throughout the year. But as Dr. Hammergren says, when things go wrong and Mercury isn't retrograde, "we don't get that hashtag. It's called Monday."

This story originally ran in 2017.


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