May 30th 1431: Joan of Arc burned at the stake

On this day in 1431, in Rouen, France the 19-year-old Joan of Arc was burned at the stake. The peasant girl, who claimed that God had chosen her and gave her divine guidance, led France’s army to several victories during the Hundred Years’ War. This long-running war aimed to liberate France from English control and establish the French crown prince Charles of Valois as King, making Joan of Arc a national heroine in France. She famously defied many of the gender norms of her day, refusing to marry, and dressing as a man in order to cross enemy territory to reach Charles’s palace. Joan had no military experience, but successfully led French forces to victory in several battles, including in the city of Orléans However, Joan of Arc was captured by the English and put on trial for witchcraft and heresy, of which she was convicted. As was customary at the time, she was burned at the stake for her crimes. She was posthumously declared innocent and made a Catholic saint; this day is often celebrated to commemorate the remarkable story of Joan of Arc.


We’re not sure exactly where she was born, or when she was born, but we know that Mary Harris was from somewhere in Cork County, Ireland, and immigrated to North America with her family as a child to escape the Irish famine. In her early twenties, she moved to Chicago, where she worked as a dressmaker, and then to Memphis, Tennessee, where she met and married George Jones, a skilled iron molder and staunch unionist. The couple had four children.  Then tragedy struck: a yellow fever epidemic in 1867 took the lives of Mary’s husband and all four children. Mary Harris Jones returned to Chicago where she continued to sew, becoming a dressmaker for the wealthy. “I would look out of the plate glass windows and see the poor, shivering wretches, jobless and hungry, walking alongside the frozen lake front,” she said. “The tropical contrast of their condition with that of the tropical comfort of the people for whom I sewed was painful to me. My employers seemed neither to notice nor to care.” Then came the Great Chicago Fire of 1871. Mary once again lost everything.

After the fire, Mary began to travel across the country. The nation was undergoing dramatic change, and industrialization was changing the nature of work. She worked with the Knights of Labor, often giving speeches to inspire the workers during strikes. She organized assistance for workers’ strikes, and prepared for workers’ marches. In June 1897, after Mary addressed the railway union convention, she began to be referred to as “Mother” by the men of the union. The name stuck. That summer, when the 9,000-member Mine Workers called a nationwide strike of bituminous (soft coal) miners and tens of thousands of miners laid down their tools, Mary arrived in Pittsburgh to assist them. She became “Mother Jones” to millions of working men and women across the country for her efforts on behalf of the miners. Mother Jones was so effective the union would send her into mines, to help miners to join unions. In addition to miners, Mother Jones also was very concerned about child workers. To attract attention to the cause of abolishing child labor, in 1903, she led a children’s march of 100 children from the textile mills of Philadelphia to New York City “to show the New York millionaires our grievances.” She led the children all the way to President Theodore Roosevelt’s Long Island home.

A political progressive, she was a founder of the Social Democratic Party in 1898. Mother Jones also helped establish the Industrial Workers of the World in 1905. For all of her social reform and labor activities, she was considered by the authorities to be one of the most dangerous women in America. In 1912, Mother Jones was even charged with a capital offense by a military tribunal in West Virginia and held under house arrest for weeks until popular outrage and national attention forced the governor to release her. In her eighties, Mother Jones settled down near Washington, D.C., in 1921 but continued to travel across the country. She died, possibly aged 100, in 1930.  Her final request was to be buried in the Miners Cemetery in Mt. Olive, Illinois, where you can visit her grave today.


Tingambato, Michoacan.

A Late Classic to Epiclassic site dating from 400 AD to 950 AD. It is unique in being one of the few sites in Michoacan that contains a ballcourt and talud tablero architecture suggesting connections with Central Mexico. It is also unique in that it contains two tombs, both consisting of chambers with a sandstone roof. These tombs are unrelated to the earlier shaft tomb culture of Jalisco, Colima, and Nayarit.


May 29th 1953: Hillary and Norgay reach Everest summit

On this day in 1953, Edmund Hillary and Sherpa Tenzing Norgay become the first people to reach the summit of the world’s highest mountain: Mount Everest. Many previous attempts to scale the peak had failed, but New Zealander Hillary and Nepalese Norgay reached the top (29,028 feet) at 11.30am local time on May 29th 1953. Norgay later revealed that Hillary had been the first to step onto the summit. The pair spent only 15 minutes taking pictures at the summit before they began their descent. Norgay left chocolates in the snow as an offering and Hillary left a cross that he had been given by John Hunt (leader of the expedition). News of their success reached London on the morning of Queen Elizabeth II’s coronation on June 2nd, and upon arrival in Kathmandu Hillary and Hunt discovered they had been knighted.

The History of Trigonometry

From LiveScience.com:

Trigonometry follows a similar path as algebra: it was developed in the ancient Middle East and through trade and immigration moved to Greece, India, medieval Arabia and finally Europe (where consequently, colonialism made it the version most people are taught today). The timeline of trigonometric discovery is complicated by the fact that India and Arabia continued to excel in the study for centuries after the passing of knowledge across cultural borders. For example, Madhava’s 1400 discovery of the infinite series of sine was unknown to Europe up through Isaac Newton’s independent discovery in 1670. Due to these complications, we’ll focus exclusively on the discovery and passage of sine, cosine, and tangent.

Beginning in the Middle East, seventh-century B.C. scholars of Neo-Babylonia determined a technique for computing the rise times of fixed stars on the zodiac. It takes approximately 10 days for a different fixed star to rise just before dawn, and there are three fixed stars in each of the 12 zodiacal signs; 10 × 12 × 3 = 360. The number 360 is close enough to the 365.24 days in a year but far more convenient to work with. Nearly identical divisions are found in the texts of other ancient civilizations, such as Egypt and the Indus Valley. According to Uta Merzbach in “A History of Mathematics” (Wiley, 2011), the adaptation of this Babylonian technique by Greek scholar Hypsicles of Alexandria around 150 B.C. was likely the inspiration for Hipparchus of Nicea (190 to 120 B.C.) to begin the trend of cutting the circle into 360 degrees. Using geometry, Hipparchus determined trigonometric values (for a function no longer used) for increments of 7.5 degrees (a 48th of a circle). Ptolemy of Alexandria (A.D. 90 to 168), in his A.D. 148 “Almagest”, furthered the work of Hipparchus by determining trigonometric values for increments of 0.5 degrees (a 720th of a circle) from 0 to 180 degrees.

The oldest record of the sine function comes from fifth-century India in the work of Aryabhata (476 to 550). Verse 1.12 of the “Aryabhatiya” (499), instead of representing angles in degrees, contains a list of sequential differences of sines of twenty-fourths of a right angle (increments of 3.75 degrees). This was the launching point for much of trigonometry for centuries to come.

The next group of great scholars to inherit trigonometry were from the Golden Age of Islam. Al-Ma'mun (813 to 833), the seventh caliph of the Abbasid Caliphate and creator of the House of Wisdom in Baghdad, sponsored the translation of Ptolemy’s “Almagest” and Aryabhata’s “Aryabhatiya” into Arabic. Soon after, Al-Khwārizmī (780 to 850) produced accurate sine and cosine tables in “Zīj al-Sindhind” (820). It is through this work that that knowledge of trigonometry first came to Europe. According to Gerald Toomer in the “Dictionary of Scientific Biography 7,” while the original Arabic version has been lost, it was edited around 1000 by al-Majriti of Al-Andalus (modern Spain), who likely added tables of tangents before Adelard of Bath (in South England) translated it into Latin in 1126.

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For people looking for History of Mathematics resources!

link submitted by grnephrite


In 1957, Laika, a stray dog from Moscow, became the first animal launched into orbit, paving the way for human space flight, which cost her her life. No provisions were made for her return, and she died after a few hours due to overheating. The Soviet government originally kept that secret and claimed she was euthanised due to oxygen depletion.

Finally, on 11 April, 2008, a monument to Laika, showing her on top of a rocket, was built near the military research facility in Moscow.


Historically accurate(?) Disney Princes

I based them off of google images so accuracy is questionable

After the success of the princesses I figured I’d do the Princes!

More to come!

Vietnam Language of War

AIRBURSTexplosion of a munition in the air

AIR CAV air cavalry, referring to helicopter-borne infantry

AIT Advanced Individual Training; the period following Basic Training, specialized training given each soldier based on his MOS (Military Occupational Specialty)

ALPHA-ALPHA automatic ambush, a combination of claymore mines configured to detonate simultaneously when triggered by a trip-wire/battery mechanism

ARC LIGHT OPERATIONS code name for the devastating aerial raids of B-52 Stratofortresses against enemy positions in Southeast Asia. The first B-52 Arc Light raid took place on June 18, 1965, on a suspected Vietcong base north of Saigon. In November 1965, B-52s directly supported American ground forces for the first time, and were used regularly for that purpose thereafter.

ARCOMS Army Commendation Medals

ARTICLE 15 summary disciplinary judgment of a soldier by his commander, could result in fines or confinement in the stockade

ARTY artillery

A.R.V.N. Army of the Republic of Vietnam (Army of South Vietnam)

BAC SI Vietnamese term for medical corpsman; doctor

BANANA CLIP banana shaped magazine, standard on the AK-47 assault rifle

BASE CAMP semi-permanent field headquarters and center for a given unit, usually within that unit’s tactical areas responsibility. A unit could operate in or away from its base camp. Base camps usually contained all or part of a given unit’s support elements.

BATTALION organizational institution in the Army and Marine Corps. Commanded by a lieutenant colonel, an infantry battalion usually has around 900 people, and an artillery battalion of about 500 people. During the Vietnam War, American battalions were usually much smaller than that.

BEEHIVE a direct-fire artillery round which incorporated steel darts (fleshettes), used as a primary base defense munition against ground attack

BIRD any aircraft, usually helicopters

BLUELEG infantryman, a.k.a. “grunt”

BOUNCING BETTY explosive that propels upward about four feet into the air and then detonates

BRIGADE basic military organizational institution. During the Vietnam War, a division was organized into three brigades, with each brigade commanded by a colonel. A division consists of approximately 20,000 people.

BRING SMOKE to direct intense artillery fire on an enemy position

CAV nickname for air cavalry

C & C command and control

CHARLIE, CHARLES, CHUCK Vietcong – short for the phonetic representation of “VC”: Victor Charlie"

CHERRY a new troop replacement

CHICKEN PLATE chest protector (body armor) worn by helicopter gunners

CHURCH KEY bottle opener

CLACKER firing device (“exploder”) for triggering claymore mines and other electrically initiated demolitions

CLAYMORE popular fan-shaped antipersonnel land mine; designed to produce a directionalized, fan-shaped pattern of fragments


COMPANY organizational institution commanded by a captain and consisting of two or more platoons; in Vietnam, varied widely in size according to mission

CRACKER BOX field ambulance

C's “C-rations”, “C-rats”, “Charlie rats”, or combat rations – canned meals used in military operations

DAP stylized, ritualized manner of shaking hands, started by African-American troops

DAPSONE small pill taken periodically by U.S. troops, ostensibly to prevent malaria but actually meant to prevent leprosy

D.M.Z. demilitarized zone

DONUT DOLLY a female American Red Cross volunteer

DOPE Marine term for the adjustments made to weapon sights; also, a term for marijuana and other illicit drugs

DOUBTFULS Vietnamese individuals who could not be categorized as either Vietcong or civil offenders; suspect personnel spotted from ground or aircraft

DUSTOFF nickname for a medical evacuation helicopter or mission

E & E escape and evasion

ECM electronic countermeasures, such as jamming, deception, and detection

ELEPHANT GRASS tall, sharp-edged grass found in the highlands of Vietnam

EM enlisted man

FIGHTING HOLE foxhole with sandbag protection and sometimes an elevated roof of sheet metal, reinforced with sand bags. Sized for one or two troops, fighting holes might be dispersed around a company or battery area for defensive use during a ground attack.

FIRECRACKERartillery round incorporating many small bomblets which are ejected over a target area and explode in “bouncing-betty” fashion – almost simultaneously; name comes from the fast popping sound (best heard at a distance)

FIREFIGHT exchange of small arms fire between opposing units

FRAG common term for any grenade

FRAGGING assassination of an officer by his own troops, usually by means of a grenade

FREEDOM BIRD any aircraft carrying soldiers back to the “world” (the U.S.A.)

FRIENDLIES U.S. troops, allies, or anyone not on the other side

FRIENDLY FIRE euphemism used during the war in Vietnam to describe air, artillery, or small-arms fire from American forces mistakenly directed at American positions

GREEN-EYE starlight scope; light amplifying telescope, used to see at night

GRUNT popular nickname for an infantryman in Vietnam; supposedly derived from the sound a soldier made from lifting up his rucksack

HANOI HILTON nickname American prisoners of war used to describe the Hoa Loa Prison in Hanoi

HOOTCH house, living quarters or a native hut

HUMP to slog around on foot


IRREGULARS armed individuals and groups not members of the regular armed forces, police, or other internal security forces

K.I.A. Killed In Action

KLICK, K short for kilometer (0.62 miles)

LAY CHILLY lie motionless

LEATHERNECK term for a Marine (Marines wore leather neckbands from 1798-1880 for protection of the neck during sword combat)

LIFER career soldier

LIGHT UP to fire on the enemy

LZ landing zone

MAD MINUTE concentrated fire of all weapons for a brief period of time at maximum rate

M.I.A .Missing In Action

NEWBIE any person with less time in Vietnam than the speaker




OUT-COUNTRY the Southeast Asian conflict outside South Vietnam (i.e., Laos and North Vietnam, sometimes Thailand, Cambodia, and China)

PLATOON approximately 45 men belonging to a company. Commanded by a lieutenant, a platoon is an organizational unit composed of two or more squads.

P.O.W. Prisoner of War

P.T.S.D. post-traumatic stress disorder

PUCKER FACTOR assessment of the “fear factor”, the difficulty or risk involved in an upcoming mission

RECON reconnaissance

RED LZ landing zone under hostile fire

ROCK ‘N’ ROLL to put an M16-A1 rifle on full automatic fire

R & R rest-and-recreation vacation taken during a one-year duty tour in Vietnam. Out-of-country R & R might be in Bangkok, Hawaii, Tokyo, Australia, Hong Kong, Manila, Penang, Taipei, Kuala Lampur, or Singapore. In-country R & R locations were at Vung Tau or China Beach.

R.V.N. Republic of Vietnam (South Vietnam)

SAPPERS North Vietnamese Army or Vietcong demolition commandos

SAR search and rescue

SEARCH AND CLEAR offensive military operations to sweep through areas to locate and attack the enemy

SEARCH AND DESTROY offensive operations designed to find and destroy enemy forces rather than establish permanent government control; also, called “Zippo missions”

SHAKE 'N’ BAKEofficer straight out of OCS (Officer Candidate School) without any combat experience

SHORT, SHORT-TIME, SHORT-TIMERindividual with little time remaining in Vietnam

SKATE goof off

SLEEPER an undercover agent or a mole

SORTIE one aircraft making one takeoff and landing to conduct the mission for which it was scheduled

STAND-DOWN period of rest and refitting in which all operational activity, except for security, is stopped

VC, CONG Vietcong

VIETCONG Communist forces fighting the South Vietnamese government

VIETMINH Viet Nam Doc Lap Dong Minh Hoi, the Vietnamese Independence League

WHITE MICE South Vietnamese police; the nickname came from their uniform white helmets and gloves

W.I.A. Wounded In Action

(THE) WORLD United States

ZIPPO flamethrower; also the brand name of a popular cigarette lighter

ZIPPO MISSION search and destroy mission

ZULU casualty report, also the phonetic pronunciation of the letter “Z”