The Reason Why Your Car's Tires Are Black

Daniel Kalisz, Getty Images
Daniel Kalisz, Getty Images

With the possible exception of some Big Wheels or other child transportation vehicles, most tires are black. You’d be hard-pressed to find a tire shop and come across a Goodyear or Michelin sample that’s any other color.

Natural rubber, however, is closer to an off-white shade, and early-model cars sported that lighter color. Early tire makers also often added zinc oxide to their natural rubber as a way to strengthen the material, resulting in white tires. But at some point, tire manufacturers decided to go darker. Why?

Jalopnik automotive journalist David Tracy pondered the question when he visited Detroit’s Ford Piquette Avenue Plant Museum and came across the white tires of a Ford Model T, a vehicle that began production in 1908. Tracy posed the question of the color transition to Michelin, which informed him that tires changed color when manufacturers began adding carbon black around 1917.

It wasn’t for cosmetic purposes. Carbon black—an elemental carbon made from the incomplete combustion of gas or oil and collected as particles—increases a tire’s durability, in part by blocking damaging UV rays that can cause rubber to crack, and by improving road grip. It also improves tensile strength, making tires more resistant to road wear.

Older tires that weren't treated with carbon black were good for 5000 miles before they needed to be replaced. Tires made with carbon black, meanwhile, could be driven for 50,000 miles or more.

There was another wrinkle: World War I led to a shortage of zinc oxide, as it was needed to make ammunition. That’s when carbon black became tire companies' go-to strengthening material (though zinc oxide does still play a role in the tire-making process today). Carbon black was initially supplied to tire manufacturer B.F. Goodrich by Binney & Smith, the company that produced Crayola crayons, which originally sourced the material for a line of ink pens.

Was that the end of the tire color evolution? Almost. Early on, companies decided to try and limit production costs by only adding carbon black to the treads, inadvertently creating the whitewall tire with a white sidewall and dark treads. The two-tone look is still popular among classic car collectors today.

[h/t Jalopnik]

Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

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Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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The Reason Supreme Court Justices Wear Black Robes

Judge Thomas Patrick Thornton (left) is sworn in as a federal judge by Judge Arthur F. Lederle (right) on February 15, 1949.
Judge Thomas Patrick Thornton (left) is sworn in as a federal judge by Judge Arthur F. Lederle (right) on February 15, 1949.

Professional attire can go a long way in communicating the level of respect you have for your occupation and the people around you. Lawyers don’t show up for court in shorts and politicians don’t often address crowds in sleeveless T-shirts.

So it stands to reason that the highest court in the country should have a dress code that reflects the gravity of their business, which is why most judges, including judges on the Supreme Court, are almost always bedecked in black robes. Why black?

As Reader's Digest reports, judges donning black robes is a tradition that goes back to judicial proceedings in European countries for centuries prior to the initial sitting of the U.S. Supreme Court in 1790. Despite that, there’s no record of whether the Justices went for a black ensemble. That wasn’t officially recorded until 1792—but the robes weren’t a totally solid color. From 1792 to 1800, the robes were black with red and white accents on the sleeves and in the front.

It is likely that Chief Justice John Marshall, who joined as the fourth chief justice of the Supreme Court in 1801, led the shift to a black robe—most likely because a robe without distinctive markings reinforces the idea that justice is blind. The all-black tradition soon spread to other federal judges.

But according to former Supreme Court Justice Sandra Day O’Connor, there is no written or official policy about the robes, and the Justices are free to source them however they like—typically from the same companies who outfit college graduates and choir singers. It’s certainly possible to break with tradition and arrive on the bench without one, as Justice Hugo Black did in 1969; Chief Justice William Rehnquist once added gold stripes to one of his sleeves. But for the most part, judges opt for basic black—a message that they’re ready to serve the law.

[h/t Reader’s Digest]