How Tattooing Really Works

BHL Book Feature: The Birds of Singapore Island

Our book feature this week is The Birds of Singapore Island (1927), co-authored by John Alexander Strachey Bucknill and Frederick Nutter Chase with SciArt by Gerald Aylmer Levett-Yeats, and published by the Raffles Museum. This work is the first book on the birds of Singapore!

Our featured illustration is a Greater Racket-tailed Drongo (Dicrurus paradiseus platurus). This book is written in an informal, non-scientific style to appeal to tourists and bird enthusiasts, and the description of the Greater Racket-tailed Drongo is a good example of this writing style.

All this week, we will be sharing several of the 31 plates from The Birds of Singapore Island, which was digitized for BHL by National Library Board, Singapore. You can view all of the plates from this work in our Flickr album, and check out our blog post, which was written by Ong Eng Chuan, Senior Librarian of the National Library Board, Singapore. 

Molecule of the Day - DDT

Dichlorodiphenyltrichloroethane (C14H9Cl5), more commonly known as DDT, is a colourless, tasteless solid under room conditions. It was used as an insecticide during the 1940s-1970s, and gained notoriety after Rachel Carson’s 1962 book, Silent Spring, which highlighted the health and environmental effects of DDT.

DDT acts by binding to voltage-gated sodium ion channels of neurons (as seen on the left of the diagram below), causing these channels to be permanently open instead of opening only upon the arrival of an action potential. Consequently, there is a continuous influx of Na+ ions into the neuron, which triggers a series of rapid action potentials and hence neuronal impulses. This leads to rapid muscle contractions, spasms, and death.

While this effect does not occur in humans and other non-insects, it is still moderately toxic, and as been shown to be an endocrine disruptor. Therefore, chronic exposure to it can lead to tumour formation, developmental problems, and birth defects. DDT is also considered to be a possible carcinogen.

Due to the hydrophobicity of DDT, it tends to accumulate in the lipids of living organisms rather than in the environment. This results in biomagnification, in which its concentration increases upon going up the food chain, as each organism of a rung of the chain consumes multiple prey. Consequently, the usage of DDT affected the populations of many birds of prey, such as the bald eagle.

In 1962, Rachel Carson published the book Silent Spring, which highlighted the negative effects of the usage of DDT and other pesticides on the environment and biodiversity. This book was revolutionary; it sparked a heated debate on pesticides and contributed to the 1972 US ban on DDT. The world followed suit; most countries around the world now prohibit the use of DDT, except for limited disease vector control purposes, such as for malaria.

DDT is synthesised by the condensation of a molecule of chloral and 2 molecules of chlorobenzene via an electrophilic substitution reaction, producing water as a by-product.

Could you explain this tfw no ZF joke? I really dont get it... :D

Get ready for a long explanation! For everyone’s reference, the joke (supplied by @awesomepus​) was:

Q: What did the mathematician say when he encountered the paradoxes of naive set theory?A: tfw no ZF

You probably already know the ‘tfw no gf’ (that feel when no girlfriend) meme, which dates to 2010. I’m assuming you’re asking about the ZF part.

Mathematically, ZF is a reference to Zermelo-Fraenkel set theory, which is a set of axioms commonly accepted by mathematicians as the foundation of modern mathematics. As you probably know if you’ve taken geometry, axioms are super important: they are basic assumptions we make about the world we’re working in, and they have serious implications for what we can and can’t do in that world. 

For example, if you don’t assume the Parallel Postulate (that consecutive interior angle measures between two parallel lines and a transversal sum to 180°, or twice the size of a right angle), you can’t prove the Triangle Angle Sum Theorem (that the sum of the angle measures in any triangle is also 180°). It’s not that the Triangle Angle Sum Theorem theorem is not true without the Parallel Postulate — simply that it is unprovable, or put differently, neither true nor false, without that Postulate. Asking whether the Triangle Angle Sum Theorem is true without the Parallel Postulate is really a meaningless question, mathematically. But we understand that, in Euclidean geometry (not in curved geometries), both the postulate and the theorem are “true” in the sense that we have good reason to believe them (e.g., measuring lots of angles in physical parallel lines and triangles). Clearly, the axioms we choose are important.

Now, in the late 19th and early 20th century, mathematicians and logicians were interested in understanding the underpinnings of the basic structures we use in math — sets, or “collections,” being one of them, and arithmetic being another. In short, they were trying to come up with an axiomatic set theory. Cantor and Frege were doing a lot of this work, and made good progress using everyday language. They said that a set is any definable collection of elements, where “definable” means to provide a comprehension (a term you’re familiar with if you program in Python), or rule by which the set is constructed.

But along came Bertrand Russell. He pointed out a big problem in Cantor and Frege’s work, which is now called Russell’s paradox. Essentially, he made the following argument:

Y’all are saying any definable collection is a set. Well, how about this set: R, the set of all sets not contained within themselves. This is, according to you, a valid set, because I gave that comprehension. Now, R is not contained within itself, naturally: if it is contained within itself, then it being an element is a violation of my construction of R in the first place. But R must be contained within itself: if it’s not an element of itself, then it is a set that does not contain itself, and therefore it is an element of itself. So we have that R ∈ R and also R ∉ R. This is a contradiction! Obviously, your theory is seriously messed up.

This paradox is inherently a part of Cantor and Frege’s set theory — it shows that their system was inconsistent (with itself). As Qiaochu Yuan explains over at Quora, the problem is exactly what Russell pointed out: unrestricted comprehension — the idea that you can get away with defining any set you like simply by giving a comprehension. Zermelo and Fraenkel then came along and offered up a system of axioms that formalizes Cantor and Frege’s work logically, and restricts comprehension. This is called Zermelo-Fraenkel set theory (or ZF), and it is consistent (with itself). Cantor and Frege’s work was then retroactively called naive set theory, because it was, of course, pretty childish:

There are two more things worth knowing about axiomatic systems in mathematics. First, some people combine Zermelo-Fraenkel set theory with the Axiom of Choice¹, resulting in a set theory called ZFC. This is widely used as a standard by mathematicians today. Second, Gödel proved in 1931 that no system of axioms for arithmetic can be both consistent and complete — in every consistent axiomatization, there are “true” statements that are unprovable. Or put another way: in every consistent axiomatic system, there are statements which you can neither prove nor disprove.For example, in ZF, the Axiom of Choice is unprovable — you can’t prove it from the axioms in ZF. And in both ZF and ZFC, the continuum hypothesis² is unprovable.³ Gödel’s result is called the incompleteness theorem, and it’s a little depressing, because it means you can’t have any good logical basis for all of mathematics (but don’t tell anyone that, or we might all be out of a job). Luckily, ZF or ZFC has been good enough for virtually all of the mathematics we as a species have done so far!

The joke is that, when confronted with Russell’s paradox in naive set theory, the mathematician despairs, and wishes he could use Zermelo-Fraenkel set theory instead — ‘that feel when no ZF.’

I thought the joke was incredibly funny, specifically because of the reference to ‘tfw no gf’ and the implication that mathematicians romanticize ZF (which we totally do). I’ve definitely borrowed the joke to impress friends and faculty in the math department…a sort of fringe benefit of having a math blog.

– CJH

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Kilroy Was Here!

He’s engraved in stone in the National World War II Memorial in Washington, DC – back in a small alcove where very few people have seen it. For the WWII generation, this will bring back memories. For younger folks, it’s a bit of trivia that is an intrinsic part of American history and legend.

Anyone born between 1913 to about 1950, is very familiar with Kilroy. No one knew why he was so well known….but everybody seemed to get into it. It was the fad of its time!

          At the National World War II Memorial in Washington, DC

So who was Kilroy?

In 1946 the American Transit Association, through its radio program, “Speak to America,” sponsored a nationwide contest to find the real Kilroy….now a larger-than-life legend of just-ended World War II….offering a prize of a real trolley car to the person who could prove himself to be the genuine article.

Almost 40 men stepped forward to make that claim, but only James Kilroy from Halifax, Massachusetts, had credible and verifiable evidence of his identity.

“Kilroy” was a 46-year old shipyard worker during World War II (1941-1945) who worked as a quality assurance checker at the Fore River Shipyard in Quincy, Massachusetts (a major shipbuilder for the United States Navy for a century until the 1980s).  

His job was to go around and check on the number of rivets completed. (Rivets held ships together before the advent of modern welding techniques.) Riveters were on piece work wages….so they got paid by the rivet. He would count a block of rivets and put a check mark in semi-waxed lumber chalk (similar to crayon), so the rivets wouldn’t be counted more than once.

                                     A warship hull with rivets

When Kilroy went off duty, the riveters would surreptitiously erase the mark. Later, an off-shift inspector would come through and count the rivets a second time, resulting in double pay for the riveters!

One day Kilroy’s boss called him into his office. The foreman was upset about unusually high wages being “earned” by riveters, and asked him to investigate. It was then he realized what had been going on. 

The tight spaces he had to crawl in to check the rivets didn’t lend themselves to lugging around a paint can and brush, so Kilroy decided to stick with the waxy chalk. He continued to put his check mark on each job he inspected, but added ”KILROY WAS HERE!“ in king-sized letters next to the check….and eventually added the sketch of the guy with the long nose peering over the fence….and that became part of the Kilroy message.

   Kilroy’s original shipyard inspection “trademark” during World War II

Once he did that, the riveters stopped trying to wipe away his marks.

Ordinarily the rivets and chalk marks would have been covered up with paint. With World War II on in full swing, however, ships were leaving the Quincy Yard so fast that there wasn’t time to paint them. As a result, Kilroy’s inspection “trademark” was seen by thousands of servicemen who boarded the troopships the yard produced.

His message apparently rang a bell with the servicemen, because they picked it up and spread it all over the European and the Pacific war zones.

Before war’s end, “Kilroy” had been here, there, and everywhere on the long hauls to Berlin and Tokyo. 

To the troops outbound in those ships, however, he was a complete mystery; all they knew for sure was that someone named Kilroy had “been there first.” As a joke, U.S. servicemen began placing the graffiti wherever they landed, claiming it was already there when they arrived.

As the World War II wore on, the legend grew. Underwater demolition teams routinely sneaked ashore on Japanese-held islands in the Pacific to map the terrain for coming invasions by U.S. troops (and thus, presumably, were the first GI’s there). On one occasion, however, they reported seeing enemy troops painting over the Kilroy logo!

Kilroy became the U.S. super-GI who had always “already been” wherever GIs went. It became a challenge to place the logo in the most unlikely places imaginable. (It is said to now be atop Mt. Everest, the Statue of Liberty, the underside of the Arc de Triomphe in Paris, and even scrawled in the dust on the moon by the American astronauts who walked there between 1969 and 1972.

In 1945, as World War II was ending, an outhouse was built for the exclusive use of Allied leaders Harry Truman, Joseph Stalin, and Winston Churchill at the Potsdam Conference. It’s first occupant was Stalin, who emerged and asked his aide (in Russian), “Who is Kilroy?”

To help prove his authenticity in 1946, James Kilroy brought along officials from the shipyard and some of the riveters. He won the trolley car….which he attached to the Kilroy home and used to provide living quarters for six of the family’s nine children….thereby solving what had become an acute housing crisis for the Kilroys.

                     The new addition to the Kilroy family home.

                                        *          *          *          *

And the tradition continues into the 21st century…

In 2011 outside the now-late-Osama Bin Laden’s hideaway house in Abbottabad, Pakistan….shortly after the al-Qaida-terrorist was killed by U.S. Navy SEALs. 

>>Note: The Kilroy graffiti on the southwest wall of the Bin Laden compound pictured above was real (not digitally altered with Microsoft Paint, as postulated by some). The entire compound was leveled in 2012 for redevelopment by a Pakistani company as an amusement park….and to avoid it becoming a shrine to Bin Laden’s nefarious memory.

                                         *          *          *          *

A personal note….

My Dad’s trademark signature on cards, letters and notes to my sisters and I for the first 50 or so years of our lives (until we lost him to cancer) was to add the image of “Kilroy” at the end. We kids never ceased to get a thrill out of this….even as we evolved into adulthood. 

To this day, the “Kilroy” image brings back a vivid image of my awesome Dad into my head….and my heart!

Dad: This one’s for you!

Science Fact Friday: Tetrodotoxin, ft. a small gif because I’m avoiding my real obligations. Why does tetrodotoxin not affect its host? More studies need to be done but at least a few species possess mutated sodium ion channels. The tetrodotoxin can’t interact efficiently with the altered channels.

Another interesting tidbit: Animals with tetrodotoxin can lose their toxicity in captivity. It is suspected that the animals accumulate the toxic bacteria as a side-effect of their diet. After several years of captivity on a tetrodotoxin-bacteria-free diet, the bacterial colonies living in the animals die, residual toxin is cleared from the system, and the animal is safe to handle.

Throughout the Watergate scandal, Richard Nixon and his supporters accused the press of being biased against his administration. In response to the criticism, Time, which had done significant investigative work on Watergate, took a moment for self-reflection with a July 8, 1974, cover story examining the press’ role in the event. Weighing the notion that the press had become too involved for its own good, the magazine still concluded that further investigation was necessary: 

“If the press were to stop digging, analyzing and attempting to keep the record straight, the investigative momentum could easily falter once more. The press can help assure that the constitutional process continues to function. After all that has happened, the country is entitled to a definitive verdict.”

Nevertheless, accusations persisted that Time and other publications were merely pursuing a liberal agenda. In February 1976 Reed Irvine and his conservative organization Accuracy in Media bought a full-page ad in the Washington Post to print a story alleging that Democratic National Committee officials knew about plans to break into the Watergate offices beforehand. The ad implied that the DNC was something other than an innocent victim and that the press had refused to make this assertion for partisan reasons. In this memo from Time’s Washington Bureau correspondent Hays Gorey to his editors, Gorey outlines the investigation done into the potential story and defends the consensus among his colleagues that it did not merit publication. He writes:

“I’m sure Reed Irvine can wow audiences by telling this story and claiming it is news being covered up. But where are his facts? Hundreds of Watergate stories went unwritten and unpublished because there were no facts to support them. This is one.“

Time July 8, 1974 cover reprint. Time Inc. Records. Editor-in-Chief: Hedley Donovan Files: Subject Files: 1959-1979: Time: Bias. New-York Historical Society.

Hays Gorey to Hedley Donovan, Henry Grunwald, and D. Duncan. February 27, 1976. Time Inc. Records. Editor-in-Chief: Hedley Donovan Files: Subject Files: 1959-1979: [Time: Bias: Kennedy and Nixon]. New-York Historical Society.

Processing of the Time Inc. Archive is made possible through the generous support of the Henry Luce Foundation

The Pirate Queen of the South China Sea

The Red Flag Fleet under Ching Shih’s rule went undefeated, despite attempts by Qing dynasty officials, the Portuguese navy, and the East India Company to vanquish it. After three years of notoriety on the high seas, Ching Shih finally retired in 1810 by accepting an offer of amnesty from the Chinese government. Ching Shih died in 1844, at the ripe old age of 69.At the dawn of the 1800s, a former prostitute from a floating brothel in the city of Canton was wed to Cheng I, a fearsome pirate who operated in the South China Sea in the Qing dynasty. Though the name under which we now know her, Ching Shih, simply means “Cheng’s widow,” the legacy she left behind far exceeded that of her husband’s. Following his death, she succeeded him and commanded over 1,800 pirate ships, and an estimated 80,000 men.

Her husband, Ching I, was the formidable commander of the Red Flag Fleet of pirate ships. He married a 26-year-old Ching Shih in 1801. She quickly took to the pirate life and when Ching I died six years later, Ching Shih wasn’t going to let Ching I’s adopted son, Cheung Po Tsai take over.  Cheung Po Tsai, however, was more than just Ching Shih’s adopted son –-  the young man had also been Ching I’s lover.

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The @unirdg-collections Squint

The University of Reading holds the archive of original artwork for the much-loved Ladybird children’s book. This painting on board was used to illustrate Exploring Space, a Ladybird ‘Achievements’ Book first published in 1964. The artwork was created by Brian Knight.

If you look closely at the painting, you can see the faint trace of Knight’s initial design for the lunar landing module - just visible under the later amendment.

Published before the first Moon landing in 1969, the fantasy spacecraft was sleek and utopian. It typifies the extent to which The Space Race captured our mid-century imaginations and permeated visual culture. The later correction, based on the Eagle Lunar Module, was printed in subsequent revisions to the book. It was an acknowledgment of a successful mission and testament to Ladybird’s emphasis on accuracy for its young readers.

All artwork is © Ladybird Books Ltd.

Your pocket Constitution

The amazing Khizr Khan was onto something with his pocket U.S. Constitution - and our Labs team went ahead and made an app for that. Understanding the U.S. Constitution is an app that allows you to view the articles and amendments of the Constitution, and then links you to scholarship relating to each specific section. It’s free for iOS and Android. Keep fighting the good fight against “alternative facts.” 

More here: http://labs.jstor.org/constitution/

Julie D’Aubigny was a 17th-century bisexual French opera singer and fencing master who killed or wounded at least ten men in life-or-death duels, performed nightly shows on the biggest and most highly-respected opera stage in the world, and once took the Holy Orders just so that she could sneak into a convent and shag a nun.

(via Feminism)