The Unexpected Optical Illusion Hidden in a Stack of Chairs

iStock
iStock

When you’re a scientist who studies vision, everything you see is inspiration. Such is the case for Nicholas Scott-Samuel, a researcher at the University of Bristol studying visual perception, whose latest work was inspired by a stack of chairs in an office. As BPS Research Digest reports, his new article in i-PERCEPTION explores an impossible-seeming optical illusion. It's formed by stacks of a certain type of chair with legs that make a square on each side of the chair (meaning the bottoms of the legs are connected by a bar).

Scott-Samuel et al., i-PERCEPTION (2018)

When you look at it head-on, the stack of squares gives you an illusion of great depth, as if the bottom bars of the chair legs stick out rather than stack vertically, and you may not be able to tell which of the legs is on top and which is on the bottom—especially if you’re looking at the drawing of the illusion, rather than at the photo of the chairs.

To explore why a stack of chairs might look so warped, Scott-Samuel and a few other researchers recruited 40 people on Facebook to ask them whether they found the image visually confusing. They did, but only if the stack contained a certain number of chairs—at nine chairs the illusion held, but any number less than four looked totally normal.

The researchers liken the effect to the Penrose triangle, an impossible shape that’s similar to a Möbius strip. But unlike the Penrose triangle, this one is actually possible, as long as you look at it from the correct angle. As the paper states: “Nick Scott-Samuel (in whose office the illusion was observed) reports that it obtains in real life as well as in images, even when sober.”

The paper is extra-short—the author’s bios are longer than the actual contents of the article—demonstrating that science doesn’t have to be a supremely arduous, heavy endeavor. At least not any heavier than a stack of chairs.

Love optical illusions? Try your eye at this one.

[h/t BPS Research Digest]

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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KFC's Fried Chicken-Scented Firelogs Are Available at Walmart This Year

Forget the smell of warm cookies. Your home can now smell like fried chicken.
Forget the smell of warm cookies. Your home can now smell like fried chicken.
Walmart

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The famous 11 herbs and spices recipe for Kentucky Fried Chicken (KFC) remains a closely guarded secret. But that doesn’t mean you can’t take home a firelog that will crackle with the aroma of a fresh bucket of fried chicken this holiday season.

All the smell, none of the calories.Walmart

The KFC 11 Herbs and Spices Firelog ($16) has been a popular novelty purchase for the past two years, and this year, it’s available exclusively at Walmart. Made in partnership with Enviro-Log, the flammable product releases a scent reminiscent of KFC’s distinctive seasoning combination, which the company promises will last around two and a half hours while burning.

KFC originally sold the log directly through their website in 2018 and 2019, but now it's available at Walmart ($16), either on the company’s website or in select stores while supplies last (if it's sold out, Amazon or eBay may be your only other options). Considering KFC is owned by Yum! Brands, which also operates Taco Bell and Pizza Hut, perhaps a Crunch Wrap firelog is in our future.

[h/t MarketWatch]