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8 Creative Ways People Went Over the Berlin Wall

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We're approaching the 25th anniversary of the Berlin Wall coming down (November 9, 1989). Although the East German government fortified the barrier with everything from watchtowers to guard dogs to beds of nails, a few people managed to slip over the border in amazing ways.

1. On a Tightrope

East German acrobat Horst Klein made one of the most daring escapes over the wall in early 1963. Thanks to his acrobatic skill, Klein was able to turn an unused high-tension cable that stretched over the wall into his route. He moved hand-over-hand while dangling from the cable 60 feet over the head of patrolling guards, then when his arms became fatigued, he swung his whole body up over the cable and inched his way along. Klein’s dismount wasn’t particularly graceful – he fell off of the cable – but he landed in West Berlin.

2. Down a Zip Line

On March 31, 1983, friends Michael Becker and Holger Bethke took Klein’s idea one step further by letting gravity do the heavy lifting for them. The pair climbed to the attic of a five-story building on the eastern side of the wall and fired an arrow tied to a thin fishing line over a building in West Berlin. An accomplice grabbed the arrow and reeled in the line, which was connected to a slightly heavier fishing line, then to a quarter-inch steel cable. Once the steel cable was attached to a chimney on the western side of the wall, Becker and Bethke zipped across the quarter-inch cable using wooden pulleys.

3. Without a Windshield

When Austrian lathe operator Heinz Meixner pulled up to Checkpoint Charlie on May 5, 1963, something must have seemed odd about his red Austin Healey Sprite convertible. Namely, it was missing its windshield. (A closer inspection would also have revealed that his mother was hiding in the trunk.) When the East German guard directed Meixner to pull over to a customs shed, Meixner instead floored the accelerator and ducked. His tiny car slipped right under the three-foot-high barrier dividing the East from the West.

4. With a Passport from Hef

A 1986 Los Angeles Times piece by Gordon E. Rowley described Meixner’s driving escape, but it also detailed a decidedly low-tech method of crossing the border. According to Rowley, some border crossers simply approached the guards and flashed their membership cards for Munich’s Playboy Club. The cards so closely resembled diplomatic passports that the guards often waved them through.

5. On a Speeding Train

These clever escapes all worked, but in the wall’s early days, brute force was an option, too. In December 1961, a 27-year-old train engine driver named Harry Deterling piloted what he dubbed “the last train to freedom” across the border. Instead of slowing down his passenger train as it approached the fortifications, Deterling throttled it up to full speed and ripped through the wall.

The train skidded to a stop in West Berlin’s Spandau borough, allowing Deterling, seven members of his family, and 16 other people aboard the train to remain in the West. The train’s engineer and six other passengers chose to return to East Germany.

6. In a Hot Air Balloon

The escape orchestrated by Hans Strelczyk and Gunter Wetzel in 1979 sounds like it came straight out of a comic book. Strelczyk, a mechanic, and Wetzel, a mason, used their mechanical know-how to build a hot air balloon engine out of old propane cylinders. Their wives then pieced together a makeshift balloon from scraps of canvas and old bed sheets, and on September 16, 1979, the two couples, along with their four children, floated up to 8,000 feet and drifted over the wall to freedom.

7. In a Well-Aged Tunnel

In May 1962, a dozen people escaped from the East by way of Der Seniorentunnel, otherwise known as “the Senior Citizens’ Tunnel.” Led by an 81-year-old man, a group of senior citizens had spent 16 days digging a 160-foot-long and 6-foot-tall tunnel from an East German chicken coop all the way to the other side of the wall. According to one of the diggers, the tunnel was so tall because the old men wanted “to walk to freedom with our wives, comfortably and unbowed.”

8. In a Uniform

Movies tend to portray East German border guards as soulless automatons who were dead-set on keeping everyone on their side of the wall, but many of the guards were just as desperate to escape as their fellow East Germans. One perk of being a border guard was that a soldier could simply wander over the border to freedom, and a lot of them did. Over 1,300 made the jump in the first two years of the wall’s existence.

The most famous of these escapes was made by 19-year-old guard Conrad Schumann on August 15, 1961, just the third day of the wall’s construction. Since the “wall” was really just piles of barbed wire at that point, Schumann jumped over the wire in his uniform while toting his machine gun. A photographer caught Schumann’s flying leap, and the jump to freedom became an iconic Cold War image. Schumann eventually settled in the southwestern state of Bavaria and worked as a machine operator. He committed suicide in 1998.

This post originally appeared in 2011.

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iStock // Ekaterina Minaeva
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Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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May 23, 2017
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