
[Image from John's Nautical & Boatbuilding Pages]
Buying a manufactured sail can be very expensive. If you are making your own vehicle and want to experiment with wind-driven propulsion, you might want to check out the idea of using building wrap as a way of forming your sails:
Now plan the sail. For this first sail, let's not have battens; they would complicate things a lot. Draw a picture of it, and figure out if you can make the sail without a seam. Remember, as you draw it, there will be curve to the luff to shape the sail. And also, at each edge the sail will be two inches wider, for the taped hem. If you do need a seam, plan to use the edge of the material at the leach, and run the seam parallel to the leach, as in the sketch. Located in this way the force across the seam, tending to pull it apart, is kept at a minimum.Let's make the leach and foot absolutely straight, unless the foot is to be attached to a spar. But any edge attached to a spar needs to be curved in order to get shape into the sail. The deepest part of the curve, for a reasonably stiff mast, ought to be one third of the way up the luff from the tack, and its depth should be one inch for each five feet of luff (or foot). By the way, for now let's call that point "D" for now. More about it later.
Now you need a gym or a dance floor, or something like that. You can guarantee the owner that you will not harm it. And you and your helper, if you have one, will for sure need a set of knee pads, like volleyball players and flooring people use, or you will come away with sore knees.
I like the suggestions on how to source the materials as inexpensively as possible, and the flexibility of the design. If you have tried this out, show us some photos or other documentation!
You can use the techniques for making a sail like this for your nascent parking lot surfer, kite, or other wind-powered transport. You will probably want to build and test a few before letting the shoreline leave your line of sight. Once you get the hang of the designing technique, then you may want to take the best of your plans to a professional sailmaker to have a formal, durable sail made up.
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This week on CRAFT we saw:
CRAFT Video: Embroidery 101 at Maker Faire
How-To: Build a Birch Log Table
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Phil Lapsley, vintage computing history buff, writes:
VintageTech, the organizers of the Vintage Computer Festival, are moving their warehouse of historical computers, equipment, software, and documentation from Livremore, CA to Stockton, CA. Volunteers are needed today (Sunday) and tomorrow (Monday) in Livermore to help pack and palletize all their wonderful machines and related ephemera. It is an amazing chance to help a good cause and get up close and personal with a bunch of interesting historical stuff. I have posted a set of photos of some of their wonders at this Flickr link. If you can spare some time, even an hour or two, please contact Sellam Ismail at sellam@vintagetech.com.
Joshua Foer is a guest blogger on Boing Boing. Joshua is a freelance science journalist and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Dylan Thuras.
My wife and I are in the process of relocating from Brooklyn to New Haven. So far, the most tedious part of the move has been packing up the collection of death masks we acquired once upon a time in a fortuitous eBay bonanza:

The majority of these heads are gazillionth-order plaster cast reproductions (knock-offs of knock-offs of knock-offs) of originals held in the Laurence Hutton Collection at Princeton. Several are actually life masks, originally cast by sculptors.
In roughly bottom-to-top, left-to-right order, the faces in this photo belong to:
On the ledge: Abraham Lincoln, Laurence Barrett, Sir Richard Owen, Robert E. Lee, John C. Calhoun, William Tecumseh Sherman
The bottom six hanging on the wall: Ludwig van Beethoven, Antonio Canova, John Keats, Hyrum Smith, Joseph Smith, Jean-Paul Marat
The next highest six: Franz Liszt, Napoleon Bonaparte (well, maybe), Frederick the Great, George Washington, William Blake, Oliver Cromwell
The next highest five: Jeremy Bentham, Aaron Burr, Friedrich Nietzsche, Edward Kean, Ulysses S. Grant
And the top row: Jonathan Swift, Maria Malibran, David Garrick, Thomas Paine, and Thomas Moore.
On another wall not pictured we've got: Robespierre, another Abe Lincoln, Frederic Chopin, Pope Pius IX, Benjamin Disraeli, Benjamin Franklin, and John Dilinger. Plus there are a few more whose names I've forgotten in storage.
If there's one death mask I wish we had, it would be the Inconnue de la Seine.
Joshua Foer is a guest blogger on Boing Boing. Joshua is a freelance science journalist and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Dylan Thuras.

Following up on Dylan's post about the Electrum, the world's largest Tesla Coil, I'd like to mention my own favorite super-sized scientific instrument: the Jantar Mantar astronomical complex in Jaipur, India. Constructed almost three centuries ago, its 73-foot-tall sundial is the largest in the world:
In 1728, Sawai Jai Singh II, rajah of Jaipur, dispatched his emissaries across the globe to gather the most accurate astronomical data possible. When they returned, Jai Singh ordered the construction of the Jantar Mantar complex, a monumental astronomical observatory constructed entirely out of stone and based on the astronomical tables of the French mathematician Phillipe de la Hire. Among the stone instruments Jai Singh constructed was the Samrat Yantra, a 73-foot tall sundial which remains the largest ever built. Though indistinguishable in design from other dials of the day, it was far and away the most accurate. Its two-second interval markings are more precise than even la Hire's table.
UPDATE: Uh oh. The picture above is of the Jantar Mantar complex in Delhi. Here's a photo of the one in Jaipur:

UPDATE TO THE UPDATE: Oy. That second picture, which I nabbed off Wikipedia, may still not be the right Jantar Mantar. This one, I am confident, is definitely the Jantar Mantar in Jaipur. Sorry for the confusion.

Joshua Foer is a guest blogger on Boing Boing. Joshua is a freelance science journalist and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Dylan Thuras.

To follow up on Dylan's post about Ball's Pyramid, we've got a whole category of "Anomalous Islands" in the Atlas Obscura that is waiting to be filled out. One of my favorites is La Gomera, a small island in the Canaries, where people communicate with each other from miles apart using one of the most unusual languages in the world:
Known as Silbo, the whistling language of Gomera Island has a vocabulary of over 4,000 words, and is used by "Silbadors" to send messages across the island's high peaks and deep valleys.
Though Silbo was on the verge of extinction in the 1990s, the Gomerans have made a concerted effort to revive their language by adding it to the public school curriculum. Today 3,000 schoolchildren are in the process of learning it.
Here's a sampling of the language:
Joshua Foer is a guest blogger on Boing Boing. Joshua is a freelance science journalist and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Dylan Thuras.

Before the telegraph, there was the optical telegraph, a chain of towers topped by large pivoting cross members, and spaced as far apart as the eye could see. Developed by the Frenchman Claude Chappe at the end of the 18th century, optical telegraph lines once stretched from Paris out to Dunkirk and Strasbourg, and were in service for more than half a century:
Chappe created a language of 9,999 words, each represented by a different position of the swinging arms. When operated by well-trained optical telegraphers, the system was extraordinarily quick. Messages could be transmitted up to 150 miles in two minutes.
Several optical telegraph relay stations are still around, including one in Saverne, France that was renovated in 1998.
Joshua Foer is a guest blogger on Boing Boing. Joshua is a freelance science journalist and the co-founder of the Atlas Obscura: A Compendium of the World's Wonders, Curiosities, and Esoterica, with Dylan Thuras.

Graham Burnett wrote a fascinating essay in Cabinet recently about otolithic organs, the pair of sensors in the inner ear that help us stay balanced and maintain inertia. "Grossly speaking," writes Burnett, the otolithic organs consist of "a bunch of tiny pebbles (of the white rock known as calcium carbonate) embedded in a gooey wad that sits atop a carpet of delicate hairs." In humans, those "pebbles" are practically microscopic, but in fish, they can be as large as marbles:
There are several thousand researchers around the world who spend their whole working day looking at fish otoliths. This has nothing to do with their physiological functions, however, and everything to do with their structure and the staggering amount of information they contain. In the first place, each species of fish has a unique otolith shape. Couple this with the fact that they are stone (and therefore comparatively resistant to decomposition), and their utility as a biological marker becomes clear. Interested in the food habits of bottlenose whales? Pump their stomachs and you will end up with relatively few bones but lots of otoliths. Find an otolith expert and he or she will be able to give you a menu...
But the true wonder of these peculiar pearls lies within. Should you have occasion to tonsure a snapper or sea-bass, slicing off the top of its skull just above the eyes, you might take a moment to remove the two largest otoliths (there are, as a rule, six in all, three on each side) from their velvet seats to the right and left of the brain stem. With the heel of a knife you should be able to snap one of them in two, and then, holding it to the light, you will discern a set of concentric bands. These are growth rings--annuli--which, properly counted, will give the age of your fish in years.
Over at Mashable, Ben Parr has compiled a post with 10 of the most-viewed, and most significant, "citizen videos" to have emerged from the ongoing turmoil in Iran. A snip from his postscript, appended to the post today:
As I built this post, I saw a progression of events through the video. Unfortunately, it wasn't a good one. It puts on display escalating violence, mayhem, and turmoil. Iran is a nation in chaos, and as we monitor the situation, we must realize that social tools provide us with unfettered access to the situation. Sometimes, that access can be disturbing. The flip side though is that we can truly know what's going on in Iran.Video above: Militia firing into crowds of protesters yesterday in Tehran.
Iran Election Crisis: 10 Incredible YouTube Videos (Mashable, via Raymond Leon Roker)
The Iranian police commander, in green uniform, walked up Komak Hospital Alley with arms raised and his small unit at his side. "I swear to God," he shouted at the protesters facing him, "I have children, I have a wife, I don't want to beat people. Please go home."A Supreme Leader Loses His Aura as Iranians Flock to the Streets (NYT, via Mitch Kapor)A man at my side threw a rock at him. The commander, unflinching, continued to plead. There were chants of "Join us! Join us!" The unit retreated toward Revolution Street, where vast crowds eddied back and forth confronted by baton-wielding Basij militia and black-clad riot police officers on motorbikes.
Dark smoke billowed over this vast city in the late afternoon. Motorbikes were set on fire, sending bursts of bright flame skyward. Ayatollah Ali Khamenei, the supreme leader, had used his Friday sermon to declare high noon in Tehran, warning of "bloodshed and chaos" if protests over a disputed election persisted.
He got both on Saturday -- and saw the hitherto sacrosanct authority of his office challenged as never before since the 1979 revolution birthed the Islamic Republic and conceived for it a leadership post standing at the very flank of the Prophet.
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Iran, citizen media and media attention (Via Jay Rosen)It's been an interesting few days for people who study social media. As the protests over election results have continued in Iran, and Iranian authorities have prevented most mainstream journalists from reporting on events, there's been a great deal of focus on social media tools, which have become very important for sharing events on the ground in Iran with audiences around the world. I, like many of my friends at the Berkman Center and Global Voices, have spent much of the past two days on the phone with reporters, fielding questions about:
- Whether social media is enabling, causing or otherwise driving the protests in Iran
- How Iranian users are managing to access the internet despite widespread filtering
- The ethics (and practice) of distributed denial of service attacks as a form of information warfare
- Whether such online activities are unprecedentedRather than tell you what I and colleagues have been saying to reporters, I'll point you to one of the better stories, by Anne-Marie Corley in MIT's Technology Review - she interviews several of my Berkman and Open Net Initiative colleagues and outlines the argument many of us are making:
- Social media is probably more important as a tool to share the protests with the rest of the world than it is as an organizing tool on the ground.
- Iranians have been accessing social networking sites and blogging platforms despite years of filtering - there's a cadre of folks who understand how to get around these blocks and are probably teaching others.
- Because so many Iranians use social media tools - often to talk about topics other than politics - they're a "latent community" that can come to life and have political influence when events on the ground dictate.
(Ed. Note: The following guest essay was written by Jasmina Tešanovi?. Full text of essay continues after the jump, along with links to previous works by her shared on Boing Boing.)
Less than Human
(Video Link) Last week the Bosnian TV screened a set of private videos of the most wanted war criminal in the world, the Bosnian Serb Ratko Mladic. The video scandalized the world, and even us, those few in Serbia who don't live in denial.
We are those who believe their eyes more than their officials, who believe in facts more than in ideology, who believe that peace can come only through justice. And when I say us few, I refer to the activists, human rights lawyers, the families of Mladic's victims, and those people who, unwillingly, in one way or another, crossed the hidden path of the hidden General.
I remember, some years ago, a young human rights activist whose daily job was to hunt for war criminals. He met Mladic regularly while Mladic shopped in a bakery. My young friend gave up his job. The impotence of the law and the nonsense of politics made his life senseless.
The war criminal was frequently quoted as a hero of the Serbian people. Political rallies featured T-shirts with Mladic' s face. He was a a mythical figure, the Serbian hero sworn to kill himself rather than surrender to the Hague tribunal.
Was he hiding in the mountains, was he hiding in his Bosnian woods and caves, was he hiding in the dungeons of the Serbian army in Belgrade? Was he hiding at all? A couple of years ago two soldiers on duty close to these secret military dungeons were found dead. The official explanation was dubious: they either killed each other in a fight or committed suicide. What came out soon after was that they were allegedly witnesses of Mladic's hideout. This case is still a very suspicious mystery, since the parents and human rights activists are pursuing it relentlessly. Some time ago, the indicted private persons who supposedly helped Mladic in his hiding in Belgrade were let off the hook in a Serbian court, officially because of lack of evidence. I saw them leave the courtroom, boisterous and loud, while the witnesses were intimated and threatened. And now these home videos appear: Mladic is elderly, yet obviously not in hiding. He is our contemporary, living a normal life in recognizable neighborhood of Belgrade. He doesn't not seem hunted but protected.
Less than a year ago another war criminal Radovan Karadzic was arrested in Belgrade: disguised as a mystic alternative medicine guru Dragan Dabic. After his arrest many photos and clues circled in Belgrade: that Mladic might be disguised as a street seller, as a simple retired person in the park, even as a woman. But these videos disperse these rumors: the very last video shows Mladic with a cane, playing joyfully with snowballs. This shot confirms the rumors that he had a recent stroke, and that the footage is as recent as winter 2008.
Looking at this home movies, as boring and innocent as all family private movies are, something felt deeply wrong about them. We are looking at the world's most wanted war criminal, who executed in cold blood, in three days, 8000 people just because they were ethnic Muslims in the wrong place: cattle, less than human, as his soldiers called them.
In the gaze of the camera, he behaves as if nothing has happened. He is a simple family man. Mladic cuddles his newborn grandson with words of endearment. He hugs his always present loving wife and his devoted son. He weeps over the coffin of his daughter, who shot herself dead with his favorite gun. The horror of the vast crime he committed becomes even more gigantic. This man with emotions and ideas had no doubts about liquidating populations, without explanation, without hesitation. Mladic was considered a hero for that. From the home videos, you see this faith about his heroic deeds. He is surrounded by family friends, and even some politicians of his regime.
These people speak my language, they have the body language of my relatives from Herzegovina, but they don't speak my mind. Sincerely, they seem crazy to me. But in the real everyday politics, their presence is a shadow over Serbia. It makes everyday Serbian life seem insane.
These days, the European Community is strongly promising Serbia a new visa regime. One of the main conditions for Serbia's integration into te European Community was the arrest of Ratko Mladic. The public screening of these videos coincides with these new policy talks. It's hard to believe that timing is an accident.
Maybe we are closing in, maybe there is no other way to tell the Serbian people that Mladic is not a a superhuman hero of Serbian people, but a tottering old man, a character whose banality is classically evil.
Jasmina Tešanovi? is an author, filmmaker, and wandering thinker who shares her thoughts with BoingBoing from time to time. Email: politicalidiot at yahoo dot com. Her blog is here.
Previous essays by Jasmina Tešanovi? on BoingBoing:
- Earthquake in Italy
- 10 years after NATO bombings of Serbia
- Made in Catalunya / Lou and Laurie
- Dragan Dabic Defeats Radovan Karadzic
- Who was Dragan David Dabic?
- My neighbor Radovan Karadzic
- The Day After / Kosovo
- State of Emergency
- Kosovo
- Christmas in Serbia
- Neonazism in Serbia
- Korea - South, not North.
- "I heard they are making a movie on her life."
- Serbia and the Flames
- Return to Srebenica
- Sagmeister in Belgrade
- What About the Russians?
- Milan Martic sentenced in Hague
- Mothers of Mass Graves
- Hope for Serbia
- Stelarc in Ritopek
- Sarajevo Mon Amour
- MBOs
- Killing Journalists
- Where Did Our History Go?
- Serbia Not Guilty of Genocide
- Carnival of Ruritania
- "Good Morning, Fascist Serbia!"
- Faking Bombings
- Dispatch from Amsterdam
- Where are your Americans now?
- Anna Politkovskaya Silenced
- Slaughter in the Monastery
- Mermaid's Trail
- A Burial in Srebenica
- Report from a concert by a Serbian war criminal
- To Hague, to Hague
- Preachers and Fascists, Out of My Panties
- Floods and Bombs
- Scorpions Trial, April 13
- The Muslim Women
- Belgrade: New Normality
- Serbia: An Underworld Journey
- Scorpions Trial, Day Three: March 15, 2006
- Scorpions Trial, Day Two: March 14, 2006
- Scorpions Trial, Day One: March 13, 2006
- The Long Goodbye
- Milosevic Arrives in Belgrade
- Slobodan Milosevic Died
- Milosevic Funeral
Francesco Fondi, of GAMERSWEB, sent us this video of Hina, a manga custom version of the Kondo KHR-2HV robot. It's a scaled-down version of KHR-2HV, using 20 digital servos (KRS-788HV) plus one GWS-PICO-STD, all controlled by a small board located in the head. While it "makes coffee" only through the miracle of video editing, the dexterity and range of motion and the feeling of it being alive is pretty impressive. And I love watching a robot working an old hand-grinder.
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From all of us here at MAKE and CRAFT, we're wishing you and your loved ones a grand ol' Dad's Day! We hope you're all enjoying a fantastic day with the family. Pictured above is some DAD binary cross stitch with RAM frame by Early Bird Special.
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Photo from Paul and Sabrinas EV Stuff
Nikki likes this open source Electric Vehicle controller project. With an EV, your primary components are the motor, batteries, charger and the controller. If people can develop a design that will allow a more inexpensive and high quality motor controller, they can move the technology in a good way towards better components and systems. Nikki says:
They're looking for people to help with the project and donations to help finish the testing and documentation. It's certainly worth a go at building yourself, or working on with some students. They have some videos at YouTube of the conversion and the prototypes.
The OS EV motor controller project ReVolt wiki with a bit of info, including a set of photos showing the build process, and the MPGuino, to help keep track of your energy cost per mile.
If you are interested in the process of building an EV or even building your own electric motor controller, you will find this web site a great place to start. Our electric motor controller project involves not just us, but several gracious contributors from other sites including Ecomodder and the EV tech group.
You may want to listen in to the EVCast featuring the project.
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From the MAKE Flickr pool
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Here is a nice round-up of some simple sneaky inks. The old favorites like lemon juice and vinegar are there, but also some more sophisticated systems using stuff like cerium oxalate and iodine fuming.
From the pages of MAKE:
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