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Friday, July 20, 2018

Friday links

It's the anniversary of the 20th of July plot, the unsuccessful bomb attempt to kill Hitler in 1944.


The Bayeux Tapestry with knobs on: what do the tapestry’s 93 penises tell us?

On July 20, 1969, Neil Armstrong walked on the moon

The Scientific Quest For the Perfect S'more.

Ye Oldest Public Library in the English Speaking World.

ICYMI, Monday's links are here, and include the physics of how lawn mower blades cut grass (at 50K frames per second), spiders flying by using electricity, and the anniversary of the beginning of the atomic age (the 1945 Trinity nuclear test).

It's the anniversary of the 20th of July plot, the unsuccessful bomb attempt to kill Hitler in 1944

Unhappy German nation, how do you like the Messianic role allotted to you, not by God, nor by destiny, but by a handful of perverted and bloody-minded men? 


A few days before the attempt: Stauffenberg standing 
to attention, left, as Hitler visits the Wolf's Lair. To 
the right is Field Marshall Wilhelm Keitel, later 
executed as a war criminal
In Germany, they came first for the Jews, and I didn't speak up because I wasn't a Jew. Then they came for the Communists, and I didn't speak up because I wasn't a Communist. Then they came for the trade unionists, and I didn't speak up because I wasn't a trade unionist. Then they came for the Catholics, and I didn't speak up because I wasn't a Catholic. Then they came for me - and there was no one left to speak up. 

Pastor Martin Niemöller (attributed, in the Congressional Record of 14 June 1968) 

The greatest obstacle to being heroic is the doubt whether one may not be going to prove one's self a fool; the truest heroism is to resist that doubt; and the profoundest wisdom, to know when it ought to be resisted, and when it be obeyed. 

Nathaniel Hawthorne (The Blithedale Romance, Ch. 2) 
Es lebe unser heiliges Deutschland!
(Long live our sacred Germany!)
~ Claus Schenk Graf von Stauffenberg (wiki) (last words before a firing squad, 21 July 1944) 

Stauffenberg's bomb failed to kill Hitler after a general moved 
the briefcase containing the device; as a result the Nazi leader 
was shielded by a heavy oak table
Today is the anniversary of the denouement of the nearly-forgotten "20th of July" plot (wiki) in 1944, when a courageous, but incredibly quixotic, group of old-fashioned German patriots under the leadership of Army officer Count Claus von Stauffenberg (wiki) (1907-1944)* sought to achieve a compromise end to World War II in Europe by assassinating Adolf Hitler in his headquarters at Rastenburg, East Prussia, preparatory to opening peace negotiations with the western allies (i.e., excluding Russia). The conspiracy involved a number of high-ranking officers, including Generals Ludwig Beck and Friedrich Obert, but collapsed when a bomb placed by Stauffenberg himself failed to kill Hitler, and plans to seize Berlin fell through.  

Within a day Stauffenberg and the other ringleaders had been executed, but thousands of known opponents of the regime were killed also, and Field Marshals Erwin Rommel, Erwin von Witzleben, and Günther von Kluge were implicated and forced to commit suicide**. Ironically, within a year, the Third Reich had collapsed and Hitler was dead. English writer G. K. Chesterton (1874-1936) once wrote,
"Courage is almost a contradiction in terms. It means a strong desire to live taking the form of a readiness to die."
* N.B. Stauffenberg, a devout Roman Catholic, was born to a Bavarian noble family, entered a traditional cavalry regiment in 1926, and became an officer in the German Army in 1930. Despite growing misgivings about Nazi policies, he fought loyally in Poland, France, Russia, and Tunisia until he was seriously wounded in the latter, losing an eye, his right hand, and two fingers on his left hand. Subsequently, he served in several staff positions. Throughout his career, Stauffenberg seems to have been drawn to various anti-Nazi movements, and his war experiences, especially in Russia, intensified his feelings of unease with the regime. The 2008 motion picture Valkyrie presents a somewhat fictionalized version of the 20 July plot. 

** Stauffenberg got off easy. Eight of those executed were hanged with piano wire from meat-hooks and their executions filmed and shown to senior members of the Nazi Party and the armed forces.

British Pathe has a newsreel which includes footage of the aftermath of the bomb:


And an additional newsreel, apparently from shortly after the end of the war:


Related posts:


The Herd Reich? Brit farmer turned Nazi super cows into sausage because they were too aggressive.

January 27, 1945 - the Soviet Army liberated Auschwitz



Further reading:

The definitive source: Rise And Fall Of The Third Reich.

Parts of the text above are adapted from Ed's Quotation of the Day, only available via email - leave your email address in the comments if you'd like to be added to his list. Ed is the author of Hunters and Killers: Volume 1: Anti-Submarine Warfare from 1776 to 1943 and Hunters and Killers: Volume 2: Anti-Submarine Warfare from 1943.

Monday, July 16, 2018

Monday links

The Physics of How Lawn Mower Blades Cut Grass (at 50K frames per second).


On July 16, 1945 the atomic age began with the Trinity nuclear test. Related: 1954 film: How a Clean, Tidy Home Can Help You Survive the Atomic Bomb

Kazakhstan tax dollars at work: this 40 foot tall squirrel statue is part of an art project commissioned by city authorities.


ICYMI, Friday's links are here, and include why Friday the 13th is considered unlucky, the history of trial by combat, Bastille Day, Mozart's less family-friendly works, and how local authorities are surveilling U. S. citizens.

Sunday, July 15, 2018

The Physics of How Lawn Mower Blades Cut Grass (at 50K frames per second)

Interesting Engineering on Smarter Every Day's super slow motion video (below) of a lawnmower:
...an ordinary lawnmower sucks air up into the mower body causing the grass to stand vertically, which allows the blade to slice evenly at the bottom of the grass.
To demonstrate this in another way, a vacuum hair clipper does the same thing. It sucks hair into it before it is cut so that a really precise cut can be made. The lifting of the grass is actually caused by the tab on the back of the mower blade which causes air lift and raises the grass up.
By filming a lawn mower in action with a super fast camera, that in turn gives wonderful slow motion, you can see the blades of grass being lifted up just before being cut.

Friday, July 13, 2018

Paraskavedekatriaphobia: Why is Friday the 13th Considered Unlucky?

In case you were trying to work it out for yourself, the name of this phobia in Pig Latin is araskavedekatriaphobiapay.

Superstition, bigotry, and prejudice, ghosts though they are, cling tenaciously to life: they are shades armed with tooth and claw. They must be grappled with unceasingly, for it is a fateful part of human destiny that it is condemned to wage perpetual war against ghosts. A shade is not easily taken by the throat and destroyed. 

~ Victor Hugo, Les Misérables

Today is Friday, the 13th, which superstition holds is a day for bad luck. According to folklorists, there is no written reference to this belief before the 19th century. The earliest known reference in English occurred in an 1869 biography of composer Gioacchino Rossini, which described the irony of his dying on an "unlucky" Friday, the 13th. 

The basis for the superstition may lie in the fact that 13 has long been held to be an unlucky number and Friday an unlucky day - hence the combination. It has been estimated that something like 20 million people are affected by this belief in the United States, many of them changing their normal routines on this day to avoid "the curse." The Dutch Centre for Insurance Statistics claims that "fewer accidents and reports of fire and theft occur when the 13th of a month falls on a Friday than on other Fridays, because people are preventatively more careful or just stay home." This seems to be confirmed by Dutch auto accident data.

This Nat Geo article discusses the phobia with Donald Dossey, founder of a Stress Management Center and Phobia Institute in North Carolina (and also a folklore historian and author of Holiday Folklore, Phobias and Fun): he says that fear of Friday the 13th is rooted in ancient, separate bad-luck associations with the number 13 and the day Friday. The two unlucky entities ultimately combined to make one super unlucky day.

Dossey traces the fear of 13 to a Norse myth about 12 gods having a dinner party at Valhalla, their heaven. In walked the uninvited 13th guest, the mischievous Loki. Once there, Loki arranged for Hoder, the blind god of darkness, to shoot Balder the Beautiful, the god of joy and gladness, with a mistletoe-tipped arrow.

"Balder died and the whole Earth got dark. The whole Earth mourned. It was a bad, unlucky day," said Dossey. From that moment on, the number 13 has been considered ominous and foreboding.

There is also a biblical reference to the unlucky number 13. Judas, the apostle who betrayed Jesus, was the 13th guest to the Last Supper.

Meanwhile, in ancient Rome, witches reportedly gathered in groups of 12. The 13th was believed to be the devil.

Thomas Fernsler, an associate policy scientist in the Mathematics and Science Education Resource Center at the University of Delaware in Newark, said the number 13 suffers because of its position after 12.

According to Fernsler, numerologists consider 12 a "complete" number. There are 12 months in a year, 12 signs of the zodiac, 12 gods of Olympus, 12 labors of Hercules, 12 tribes of Israel, and 12 apostles of Jesus.

In exceeding 12 by 1, Fernsler said 13's association with bad luck "has to do with just being a little beyond completeness. The number becomes restless or squirmy."

Judas, the apostle w­ho betrayed Jesus, was the 13th person to arrive at The Last Supper
This fear of 13 is strong in today's world. According to Dossey, more than 80 percent of high-rises lack a 13th floor. Many airports skip the 13th gate. Hospitals and hotels regularly have no room number 13.

On streets in Florence, Italy, the house between number 12 and 14 is addressed as 12 and a half. In France socialites known as the quatorziens (fourteeners) once made themselves available as 14th guests to keep a dinner party from an unlucky fate.

As for Friday, it is well known among Christians as the day Jesus was crucified. Some biblical scholars believe Eve tempted Adam with the forbidden fruit on Friday. Perhaps most significant is a belief that Abel was slain by Cain on Friday the 13th.

Related: 13 Reasons People Think the Number 13 is Unlucky.

Friday links

Apocalypse alert: supermoon, solar eclipse and Friday the 13th. Paraskavedekatriaphobia: Why is Friday the 13th Considered Unlucky?

July 14 is Bastille Day. Here's Jonah Goldberg's classic article on the subject: The French are Revolting.

A Brief History of Trial by Combat.

Supercut: 100 Greatest One-Liners Before The Kill.

Mozart’s Much Less Family Friendly Works (Some NSFW language - apparently his sense of humor had a scatological component).


ICYMI, Thursday's links are here, and include the 19th century fight over Sunday mail delivery, the art and science of creating ice in the desert 2,000 years ago, sporting pastimes from the Georgian era, and some male contraceptive advice (just wear a polyester sling, and let the heat and electrostatics do all the work), with bonus Monty Python.

Thursday, July 12, 2018

Thursday links

The massive 19th century fight over Sunday mail delivery.

The U.S. Air Force Learned to Code and Saved the Pentagon Millions.

Male contraceptive advice: just wear a polyester sling, and let the heat and the electrostatics do all the work, with bonus Monty Python.

Skittles and Nine Holes, or Bumble Puppy: sporting pastimes in the Georgian era.

The Cutting-Edge Science That Can Turn Everyday Objects, Like a Bag of Chips, Into a Listening Device.

How People Created Ice in the Desert 2,000 Years Ago: the ancient art of "night-sky cooling."

ICYMI, Monday's links are here, and include Nikola Tesla's birthday, the U. S. Navy's 1920's ice cream barge, how alcohol and caffeine helped create civilization, and eye-searing fashion ads from the 1970's.

Tuesday, July 10, 2018

Male contraceptive advice: just wear a polyester sling, and let the heat and the electrostatics do all the work

Hey, it's science! 

So, is birth control just a women’s issue? Men are equally involved in producing a baby, and there are a few male-centric birth control options (i.e., condoms) available. But there’s definitely room for new male contraceptives–especially ones that aren’t permanent and don’t require last-minute application. And that’s where the polyester comes in. 

No, not this kind of sling, dummy.
Apparently, simply wearing a polyester sling (I suppose you could get one that isn't polyester, and line it yourself) around the scrotum can produce sperm-free semen (azoospermia), presumably from the heat (what’s sweatier than polyester?) and the electrostatics. The sling must be worn for months before it’s effective, and it takes another couple of months, after removal, to reverse the effects.

This makes sense, if you give it any thought (which I never have) because your balls hang low for more than one reason, and one of those reasons is temperature regulation. In order for sperm to mature successfully, they need to be kept a few degrees lower than normal body temperature, so keeping them below the body is a good way to keep things cool. 

Related stuff: 

Swinging high and low: Why do the testes hang at different levels? A theory on surface area and thermoregulation. 

and this:

Scrotal Asymmetry In Man And Ancient Sculpture which discusses the fact (?) that the left side generally seems to hang lower. 

Previous studies in dogs wearing polyester underpants showed that the dogs had reduced sperm count under those conditions:
"A recent study has shown that dogs, while wearing polyester underpants, had a diminished sperm count which was reversible when the pants were removed. In contrast, dogs wearing cotton pants showed insignificant semen changes.”
Here's the abstract from the paper on humans mentioned back at the beginning of this post (I don't, unfortunately, have a link to the dog paper), which, by the way, also fits into the "tax dollars at work" category, since it's from the NIH:


"Every 2 weeks, a physician at the Faculty of Medicine at Cairo University in Egypt examined 14 32-47 year old male volunteers wearing a polyester scrotal sling day and night for 12 months to determine if polyester fabrics can act as a contraceptive in men. 

They changed the sling only when it became dirty. None of the men dropped out of the study. The sling did not cause any complications or reactions. Their partners took an oral contraceptive until 3 sperm samples proved the men to be azoospermic. The men became azoospermic from 120-160 days (mean 139.6 days) after 1st putting on the sling. They remained azoospermic throughout the study. None of the partners became pregnant during the study. All 5 couples who wanted a pregnancy after the study period did indeed conceive. 4 had normal live births and 1 a miscarriage. The volume of their testicles fell greatly from 22.2-18.6 sd ml during the 12 months (p.05), but returned to pretest levels 75-135 days after removal. Further the mean rectal-testicular temperature difference was lower 3 months after wearing the sling than it was before they wore it (1.3-3 degrees Celsius; p.001). 3 months after they stopped wearing the sling, the mean rectal-testicular temperature difference reverted to normal. 

The polyester in the sling generated greater electrostatic potentials during the day than at night (326-395 volt/sq. cm. vs. 142-188 volt/sq. cm.; p.01). This was a result of the friction between the scrotum and the polyester sling. Germ cells of the seminiferous tubules still exhibited degenerative changes 6 months after removal of the sling. Within 140-170 days after removal, sperm concentration levels returned to pretest levels (40 million/ml). Apparently the electrostatic field effect and the disordered thermoregulatory effect of the polyester sling produced azoospermia. In conclusion, the sling is a safe, acceptable, inexpensive, and reversible method of contraception in men.”

Borat's mankini might work

 for this purpose
Somewhere in reading about this stuff I ran across this (read the whole thing), on the dangers of blogging (if you're male, that is):
When bloggers write, with laptops, seated,
Bits of them get overheated—
Sitting in their rooms, retreated
To their hidden cloisters.
If I should hear “Well done! Well done!”
I hope they mean my writing’s fun
And not some cruel and heartless pun
About my mountain oysters.
That reminded me of the Family Guy episode "Hell Comes to Quahog" (I couldn't find it on youtube), which is the episode in which Superstore comes to town. It's just after Peter gets a job at Superstore :
Peter: Boy Meg, I am so looking forward to this job. 
Brian: Peter, I can't believe you're working for Superstore USA. How could you sell out like that? 
Peter: Because Brian, they have industrial sized air conditioning. And I'm tired of sitting in ball soup.
And, of course, it's impossible to touch on this subject without including Monty Python's classic Every Sperm is Sacred skit from The Meaning Of Life:

Monday, July 9, 2018

Monday links

July 9th is Nikola Tesla's birthday: bio, Tesla coil music, Tesla vs Edison rap battle, history, videos and links.

How Alcohol and Caffeine Helped Create Civilization.

Making the World’s Largest Lemon Battery for a Lemon-Powered Car.

Fashion Ads From The 1970s. Be warned - you can't unsee these.

Science: U.S. women have a significantly larger mean breast volume than women born in other countries.

Why the U.S. Navy Once Had a Concrete Ice Cream Barge

ICYMI, most recent links are here, and are all Independence Day-related: Lincoln's 1858 speech on the eternal meaning of Independence Day plus speeches from Coolidge (1926) and Reagan (1986), the text of the Declaration of Independence, founding fathers stories, how the breaking news spread in 1776, the science of fireworks and of barbecue, and Independence Days from science fiction.

Sunday, July 8, 2018

July 9 is Nikola Tesla's birthday: bio, Tesla coil music, Tesla vs Edison rap battle, infographic from The Oatmeal

Want a quick explanation of everything Tesla? Check out this infographic at The Oatmeal.

Epic Rap Battles of History — Nikola Tesla vs Thomas Edison:


The video below is based on stories about Tesla's lost papers and documents, about how the government secreted them away somewhere: The Missing Secrets Of Nikola Tesla from The Phenomenon Archives (described as "A documentary series that takes an in-depth look at the topics found in recently de-classified government documents. It explores well-known issues with new information that has been sequestered from the public"):



Tesla Coils Play the Inspector Gadget Theme SongSweet Home Alabama (with an included explanation of how it works), and more Tesla coil music.



Wardenclyffe, Tesla's Long Island estate, was originally intended to be “a vector for trans-Atlantic wireless communications, broadcasting, and wireless power. The site consisted of an (incomplete) 18-story-high transmission tower that topped off a laboratory surrounded by 16 acres of land in Shoreham, Long Island in 1903. 

By 1917, Tesla had sold the site for $20,000 to pay bills at the Waldorf. That same year, the transmission tower was blown up by the buyers and sold for scrap. 

July 9 is the anniversary of the birth of Serbian-American electrical-engineering genius and futurist Nikola Tesla (1856-1943) (wiki), to a Serbian-Orthodox priest in Croatia. Tesla displayed remarkable intuition for mechanical and electrical phenomena while still a youth, and although he studied physics sporadically in Graz and Prague, he was largely self-taught in scientific and engineering subjects. 

In 1881. he began working at the Budapest Telephone Exchange as a technician, but within a year he transferred to an Edison subsidiary in France, designing electrical equipment. Two years later, he relocated to New York City, where he worked directly for Thomas Edison but resigned several years later in a dispute over pay. 

Subsequently, Tesla moved out on his own, eventually forming a company to commercialize his own inventions for the improvement of electric motors and generators operating largely on alternating current (vice Edison's direct current). Most importantly, he invented the concept of polyphase alternating-current power systems and the AC induction motor, which used a rotating magnetic field to propel the rotor. 

In 1888, Tesla licensed his patents to George Westinghouse, who used them to devise alternating-current alternatives to Edison's DC systems for generating and distributing electrical power, and eventually alternating current prevailed as the national standard.* 

In 1891, Tesla became an American citizen and established his own laboratory in New York City to work on a wide variety of electrical developments, including X-ray technology, radio, and high-voltage/high-frequency apparatus. Among the latter was the "Tesla coil," a device for developing extremely high voltages and creating spectacular displays of artificial lightning. 

In 1899, he moved his operations to Colorado Springs and concentrated on devising a system for the wireless transmission of electrical power through the atmosphere (but never realized it at a practical level). He also developed concepts for vertical takeoff/landing aircraft, remote controlled vehicles, and an early directed energy weapon. He ultimately received nearly 300 patents for his discoveries. 

Since Tesla had sold his most lucrative patents to Westinghouse and plowed what money he earned later into further experimentation, he died in relative poverty in 1943. Although vastly overshadowed by Edison in the popular imagination, it was Tesla who was primarily responsible for the concepts underlying the electrical power grids used world-wide today.

*The great advantage of alternating over direct current in power distribution is that the former can make use of transformers to step the voltage up and down, and high voltage is much more efficient for sending electrical power over long distances.