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The Kingdom of Boomeria

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The Kingdom of Boomeria is a magical place of just one hectare hidden in the forest in Bonny Doon, California. Students who graduate from San Lorenzo Valley High School go out into the world and tell tales of their adventures in the Kingdom of Boomeria and find that no one believes them. After all, how many people can claim their science education included fighting medieval battles, building a pipe organ, and digging an underground labyrinth?

Preston Q. Boomer has been teaching physics and chemistry at San Lorenzo Valley High near Santa Cruz for over 50 years. He has a passion for science and believes that hands-on experience helps students understand scientific concepts. He also believes science (and life in general) should be fun. His nickname is "The Boom", which they say is not because of explosions in chemistry class, although there are stories of experiments that went awry, like the time he drew the cops to the school after a Tesla coil cut off police communications. Boomer taught the grandparents of his current students, but has no plans to retire. He is the crazy mad scientist that we all wish we had for a teacher.


According to The Boom, the idea of Boomeria was born the night he used water guns to defend his home from students who planned to egg his house. He began construction on the kingdom in the mid 1950s on his 2.5 acre yard nestled in the woods. There were no neighbors at the time. Boomer's two sons, Lawrence and Alex as well as many students over the years helped construct a wooden castle with a dungeon, battle turrets complete with water cannons, a pneumatic system to power the kingdom's pipe organ, and an underground labyrinth that connects the different parts of Boomeria. The property also holds a swimming pool (which The Boom calls the "Main Aqueous Ammunition Bunker") and a chapel built around the organ.


The tunnels beneath Boomeria were dug by students over a three-year period in the 1960s. Now they are known as the Great Tunnel, the Catacombs, and the Dungeon. While digging the tunnels, students found bones of an animal that resembles a dinosaur but still hasn't been identified. The reconstructed skeleton now hangs in the command center. Next to the castle stands a full-size working guillotine, which is used only for watermelons. No one is allowed on the guillotine platform except The Boom himself. The entire property is wired with horns, sirens, bells, and other means of warning and communication. The loudest is the Weapon Beulah, a Navy foghorn that can be heard miles away. When approaching the castle, you'll be greeted by The Boom shouting "Who goes there?" to which he expects a creative and intelligent reply.


The students periodically try to conquer the kingdom using the water cannons. These battles rage fiercely, but as the kingdom's motto states, "The King Always Wins".


The water to the cannons is controlled from the Main Engine Room. The Control Room holds the telegraph system used for communication and steam engines that power other parts of Boomeria. There is also a laboratory full of ancient chemicals and more recent experiments.


The Brotherhood of Natural Philosophers is the science club The Boom's students founded in the 1960s. New recruits are taken to a party in Boomeria where they are expected to give a short science presentation, then are taken on a tour of the kingdom before being formally installed. Participation is not mandatory, as that would hint at hazing, but no one wants to miss it! There are activities all year long for club members, both inside the kingdom and elsewhere.


Preston Boomer's great-grandmother gave an 1879 pipe organ to the Trinity Paris Church in San Jose many years ago. In 1953 the church replaced that organ, and The Boom took what was left of the old organ (the console and two sets of pipes) and made it a part of Boomeria. Over the years, Boomer and his students, under the supervision of organ builders Bill Reid, John West, and Bill Visscher, repaired and expanded the original organ. Now it has 2,500 pipes! You can hear a bit of organ music at The Boom's site. Image by Flickr user graymalkn.


There are several ways you can experience Boomeria for yourself. The best way is to be a student at San Lorenzo Valley High School. If that's not possible, you can attend the annual Boomeria Extravaganza, scheduled this year for July 10th. The event is a fundraiser for the Santa Cruz Baroque Festival and will cost you $50 per ticket, but that will entitle you to an afternoon of organ music, refreshments, and a tour of the inside of the organ, as well as a look at the rest of Boomeria. The public is invited to a Christmas carol singing each year -the event for 2010 is scheduled for December 18th. If you are between 7 and 13 years old, you can attend the Celtic Music Camp held each summer at Boomeria. Otherwise, you can contact The Boom ahead of time and ask nicely. After all, it's his kingdom.

A large tree fell during a storm and damaged part of the castle last fall, but students and family helped remove the debris and insurance will cover repairs. The Boom said he would use the experience in his classroom lessons. It's just another example of how this teacher uses every opportunity to teach the principles of physics.

This post was inspired by an item at the Presurfer.

Read about other personal constructions at mental_floss: The Coral Castle, Salvation Mountain, The Watts Towers, and 7 Lifelong Personal Projects.

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iStock // Ekaterina Minaeva
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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Sponsor Content: BarkBox
8 Common Dog Behaviors, Decoded
May 25, 2017
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Dogs are a lot more complicated than we give them credit for. As a result, sometimes things get lost in translation. We’ve yet to invent a dog-to-English translator, but there are certain behaviors you can learn to read in order to better understand what your dog is trying to tell you. The more tuned-in you are to your dog’s emotions, the better you’ll be able to respond—whether that means giving her some space or welcoming a wet, slobbery kiss. 

1. What you’ll see: Your dog is standing with his legs and body relaxed and tail low. His ears are up, but not pointed forward. His mouth is slightly open, he’s panting lightly, and his tongue is loose. His eyes? Soft or maybe slightly squinty from getting his smile on.

What it means: “Hey there, friend!” Your pup is in a calm, relaxed state. He’s open to mingling, which means you can feel comfortable letting friends say hi.

2. What you’ll see: Your dog is standing with her body leaning forward. Her ears are erect and angled forward—or have at least perked up if they’re floppy—and her mouth is closed. Her tail might be sticking out horizontally or sticking straight up and wagging slightly.

What it means: “Hark! Who goes there?!” Something caught your pup’s attention and now she’s on high alert, trying to discern whether or not the person, animal, or situation is a threat. She’ll likely stay on guard until she feels safe or becomes distracted.

3. What you’ll see: Your dog is standing, leaning slightly forward. His body and legs are tense, and his hackles—those hairs along his back and neck—are raised. His tail is stiff and twitching, not swooping playfully. His mouth is open, teeth are exposed, and he may be snarling, snapping, or barking excessively.

What it means: “Don’t mess with me!” This dog is asserting his social dominance and letting others know that he might attack if they don’t defer accordingly. A dog in this stance could be either offensively aggressive or defensively aggressive. If you encounter a dog in this state, play it safe and back away slowly without making eye contact.

4. What you’ll see: As another dog approaches, your dog lies down on his back with his tail tucked in between his legs. His paws are tucked in too, his ears are flat, and he isn’t making direct eye contact with the other dog standing over him.

What it means: “I come in peace!” Your pooch is displaying signs of submission to a more dominant dog, conveying total surrender to avoid physical confrontation. Other, less obvious, signs of submission include ears that are flattened back against the head, an avoidance of eye contact, a tongue flick, and bared teeth. Yup—a dog might bare his teeth while still being submissive, but they’ll likely be clenched together, the lips opened horizontally rather than curled up to show the front canines. A submissive dog will also slink backward or inward rather than forward, which would indicate more aggressive behavior.

5. What you’ll see: Your dog is crouching with her back hunched, tail tucked, and the corner of her mouth pulled back with lips slightly curled. Her shoulders, or hackles, are raised and her ears are flattened. She’s avoiding eye contact.

What it means: “I’m scared, but will fight you if I have to.” This dog’s fight or flight instincts have been activated. It’s best to keep your distance from a dog in this emotional state because she could attack if she feels cornered.

6. What you’ll see: You’re staring at your dog, holding eye contact. Your dog looks away from you, tentatively looks back, then looks away again. After some time, he licks his chops and yawns.

What it means: “I don’t know what’s going on and it’s weirding me out.” Your dog doesn’t know what to make of the situation, but rather than nipping or barking, he’ll stick to behaviors he knows are OK, like yawning, licking his chops, or shaking as if he’s wet. You’ll want to intervene by removing whatever it is causing him discomfort—such as an overly grabby child—and giving him some space to relax.

7. What you’ll see: Your dog has her front paws bent and lowered onto the ground with her rear in the air. Her body is relaxed, loose, and wiggly, and her tail is up and wagging from side to side. She might also let out a high-pitched or impatient bark.

What it means: “What’s the hold up? Let’s play!” This classic stance, known to dog trainers and behaviorists as “the play bow,” is a sign she’s ready to let the good times roll. Get ready for a round of fetch or tug of war, or for a good long outing at the dog park.

8. What you’ll see: You’ve just gotten home from work and your dog rushes over. He can’t stop wiggling his backside, and he may even lower himself into a giant stretch, like he’s doing yoga.

What it means: “OhmygoshImsohappytoseeyou I love you so much you’re my best friend foreverandeverandever!!!!” This one’s easy: Your pup is overjoyed his BFF is back. That big stretch is something dogs don’t pull out for just anyone; they save that for the people they truly love. Show him you feel the same way with a good belly rub and a handful of his favorite treats.

The best way to say “I love you” in dog? A monthly subscription to BarkBox. Your favorite pup will get a package filled with treats, toys, and other good stuff (and in return, you’ll probably get lots of sloppy kisses). Visit BarkBox to learn more.