السبت، 26 مارس 2016

Bear Bone Discovered in 1903 is Evidence of Stone-Age Humans in Ireland

brown bear, stone age, ireland
Credit: iStockphoto.com



Since the 1970s, the earliest known evidence of human settlement in Ireland has been the hunter-gatherer settlement of Mount Sandel, located on the River Bann in County Derry, which dated back to the Mesolithic period, around 8,000 B.C. Now, scientists say a bear’s knee bone found more than a century ago in a cave on Ireland’s western coast is evidence that humans were active on the island even earlier. Recent radiocarbon dating and expert analysis indicate that seven cut marks on the knee bone were man-made during the Paleolithic period, or Stone Age—some 12,500 years ago.
In 1903, a team of archaeologists found thousands of bones in Alice and Gwendoline Cave in County Clare, on Ireland’s western coast. In their report of the excavation, the scientists noted that they had found seven cuts from a long blade on one of the bones: the patella, or knee bone, of an adult brown bear. They didn’t know much more than that, as radiocarbon dating technology wouldn’t be developed until decades later.
Flash forward to 2010, when Marion Dowd, an archaeologist at the Institute of Technology Sligo, and Ruth Carden, a research associate at the National Museum of Ireland, uncovered the bone in the museum’s collections, where it had been stored in a cardboard box since the 1920s. Carden and Dowd, a specialist in cave archaeology, thought the specimen could be important, and they applied for funding to send it for radiocarbon dating. In addition to the dating performed at Queen’s University Belfast, the two scientists sent a sample to the University of Oxford to double-check the result.
Dowd and Carden had expected a prehistoric date, but were shocked when both sets of testing came back with the same result: The bone dated all the way back to the Paleolithic period, or Stone Age. According to their findings, published in a recent issue of the journal Quaternary Science Reviews, the seven cuts were man-made and inflicted by a sharp tool on fresh bone—meaning they were made at the same time the bear was killed, around 10,500 B.C.
stone age, ireland
Credit: IT Sligo
“Archaeologists have been searching for the Irish Paleolithic since the 19th century,” Dowd told Phys.org. Over those 150 years, they occasionally found tools dating to the Stone Age, but dismissed them as objects that originated in Britain and were transported by ice sheets or other geological processes, rather than evidence of human habitation in Ireland itself. Now, Dowd said, “the first piece of the jigsaw has been revealed.”
Dowd says the cuts on the bone were likely made by someone inexperienced, who tried to cut through the bear’s tough knee joint (probably to extract the tendons) and had to make repeated attempts, leaving marks on the bone’s surface. As a possible implement, she suggested something like a long flint blade.
Dowd and Carden plan to further examine remains found in the same cave back in 1903 to see if they can find more specimens to illuminate this newly discovered chapter in Ireland’s human history. There are plenty to choose from, as the National Museum has some 2 million more specimens in its collections. According to Nigel Monaghan, keeper of the museum’s natural history division: “Radiocarbon dating is something never imagined by the people who excavated these bones in caves over a century ago, and these collections may have much more to reveal about Ireland’s ancient past.”
In addition to brown bears, the hunter-gatherers of Stone-Age Ireland would have encountered such animals as reindeer, wolves, hare, red deer and giant deer.
In addition to rewriting the history of humans in Ireland, the new find suggests intriguing implications for zoology as well. Scientists had not considered the possibility that humans might have played a role in some of the animal extinctions that occurred in Ireland during the Paleolithic period; now they will have to rethink things. As Carden put it, “This paper should generate a lot of discussion within the zoological research world and it’s time to start thinking outside the box…or even dismantling it entirely!”

الأربعاء، 23 مارس 2016

6 Things You Might Not Know About Einstein’s General Theory of Relativity

On March 19, 1916 Albert Einstein submitted his “Foundation of the General Theory of Relativity” for publication in the journal Annelen Der Physik. He had presented the final version of his theory to the Royal Prussian Academy of Sciences the previous November, and it would be published later that spring. The theory of general relativity is considered one of the most significant intellectual achievements in history, providing revolutionary insight into the fundamental nature of space and time. Scientists have been working to prove Einstein’s conclusions ever since; the final piece of the puzzle fell into place in February 2016, when scientists confirmed the detection of gravitational waves. In honor of this momentous anniversary, here are six illuminating facts you might not know about Einstein’s famous theory.
1. Einstein relied on friends and colleagues to help him develop his theory. 
Though the theory of general relativity is often presented as a work of solo genius, Einstein actually received considerable help from several lesser-known friends and colleagues in working on the math behind it. College friends Marcel Grossmann and Michele Basso (Einstein supposedly relied on Grossmann’s notes after skipping class) were especially important in the process. Einstein and Grossman, a math professor at Swiss Polytechnic, published an early version of the general relativity theory in 1913, while Besso—whom Einstein had credited in the acknowledgments of his 1905 paper on the special theory of relativity—worked extensively with Einstein to develop the general theory over the next two years. The work of the great mathematicians David Hilbert—more on him later—and Emmy Noether also contributed to the equations behind general relativity. By the time the final version was published in 1916, Einstein also benefited from the work of younger physicists like Gunnar Nordström and Adriaan Fokker, both of whom helped him elaborate his theory and shape it from the earlier version.

albert einstein
Einstein in 1905. (Credit: Topical Press Agency/Getty Images)
2. The early version of the theory contained a major error. 
The version published by Einstein and Grossmann in 1913, known as the Entwurf (“outline”) paper, contained a major math error in the form of a miscalculation in the amount a beam of light would bend due to gravity. The mistake might have been exposed in 1914, when German astronomer Erwin Finlay Freundlich traveled to Crimea to test Einstein’s theory during the solar eclipse that August. Freundlich’s plans were foiled, however, by the outbreak of World War I in Europe. By the time he introduced the final version of general relativity in November 1915, Einstein had changed the field equations, which determine how matter curves space-time.

3. Einstein’s now-legendary paper didn’t make him famous—at first. 
The unveiling of his masterwork at the Prussian Academy of Sciences—and later in the pages of Annelen Der Physik—certainly afforded Einstein a great deal of attention, but it wasn’t until 1919 that he became an international superstar. That year, British physicist Arthur Eddington performed the first experimental test of the general relativity theory during the total solar eclipse that occurred on May 29. In an experiment conceived by Sir Frank Watson Dyson, Astronomer Royal of Britain, Eddington and other astronomers measured the positions of stars during the eclipse and compared them with their “true” positions. They found that the gravity of the sun did change the path of the starlight according to Einstein’s predictions. When Eddington announced his findings in November 1919, Einstein made the front pages of newspapers around the world.

4. Another scientist (and former friend) accused Einstein of plagiarism. 
In 1915, the leading German mathematician David Hilbert invited Einstein to give a series of lectures at the University of Gottingen. The two men talked over general relativity (Einstein was still having serious doubts about how to get his theory and equations to work) and Hilbert began developing his own theory, which he completed at least five days BEFORE Einstein made his presentation in November 1915. What began as an exchange of ideas between friends and fellow scientists turned acrimonious, as each man accused the other of plagiarism. Einstein, of course, got the credit, and later historical research found that he deserved it: Analysis of Hilbert’s proofs showed he lacked a crucial ingredient known as covariance in the version of the theory completed that fall. Hilbert actually didn’t publish his article until March 31, 1916, weeks after Einstein’s theory was already public. By that time, historians say, his theory was covariant.

albert einstein
Credit: Roger Viollet/Getty Images
5. At the time of Einstein’s death in 1955, scientists still had almost no evidence of general relativity in action. 
Though the solar eclipse test of 1919 showed that the sun’s gravity appeared to bend light in the way Einstein had predicted, it wasn’t until the 1960s that scientists would begin to discover the extreme objects, like black holes and neutron stars, that influenced the shape of space-time according to the principles of general relativity. Until very recently, they were still searching for evidence of gravitational waves, those ripples in the fabric of space-time caused (according to Einstein) by the acceleration of massive objects. In February 2016, the long wait came to an end, as scientists at the Laser Interferometer Gravitational Wave Observatory (LIGO) announced they had detected gravitational waves caused by the collision of two massive black holes.

6. You can thank Einstein for GPS. 
Though Einstein’s theory mostly functions among the black holes and cosmic collisions of the heavens, or an ultra-small scale (think string theory), it also plays a role in our everyday lives. GPS technology is one outstanding example of this. General relativity shows that the rate at which time flows depends on how close one is to a massive body. This concept is essential to GPS, which takes into account the fact that time is flowing at a different rate for satellites orbiting the Earth than it is for us on the ground. As a result, time on a GPS satellite clock advances faster than a clock on the ground by about 38 microseconds a day. This might not seem like a big difference, but if left unchecked it would cause navigational errors within minutes. GPS compensates for the time difference, electronically adjusting rates of the satellite clocks and building mathematical functions within the computer to solve for the user’s exact location—all thanks to Einstein and relativity.

The Birth of the Tuskegee Airmen



On March 19, 1941, the U.S. War Department established the 99th Pursuit Squadron, which, along with a few other squadrons formed later, became better known as the Tuskegee Airmen. Consisting of America’s first black military pilots, these units confronted racism at home in addition to the enemy abroad. Yet despite the extra obstacles, they would go on to compile an exemplary record in the Mediterranean and European theaters of World War II and pave the way for desegregation of the military. Find out how this legendary unit came into being.
Tuskegee Airmen
Tuskegee Airmen receiving their commissions at the Tuskegee Army Flying School in Alabama in1942. (Credit: Afro American Newspapers/Gado/Getty Images)
On March 19, 1941, the U.S. War Department established the 99th Pursuit Squadron, which, along with a few other squadrons formed later, became better known as the Tuskegee Airmen. Consisting of America’s first black military pilots, these units confronted racism at home in addition to the enemy abroad. Yet despite the extra obstacles, they would go on to compile an exemplary record in the Mediterranean and European theaters of World War II and pave the way for desegregation of the military. Find out how this legendary unit came into being.
Though African Americans had fought in every major U.S. conflict dating back to the Revolutionary War, they were traditionally confined to menial jobs and kept separated from whites. As late as 1925, an Army War College report called them “a sub-species of the human family” that performed poorly as soldiers due to their cowardly, subservient, superstitious, amoral and mentally inferior nature. Black advocacy groups and newspapers attempted to counter such pseudoscience. But as World War II approached, the military remained staunchly opposed both to integration and to putting blacks in positions of authority. In 1940, for example, U.S. Army Chief of Staff George C. Marshall, who would later win the Nobel Peace Prize for his work on the Marshall Plan, remarked that now was “not the time for critical experiments, which would inevitably have a highly destructive effect on morale.” The navy and war secretaries agreed, with the latter writing that “leadership is not embedded in the Negro race yet” and that mixing white and black troops would be “trouble.”
Tuskegee Airmen prepare for a flight from Tuskegee Army Airfield, 1943. (Credit: Afro American Newspapers/Gado/Getty Images)
Tuskegee Airmen prepare for a flight from Tuskegee Army Airfield, 1943. (Credit: Afro American Newspapers/Gado/Getty Images)
Not surprisingly, given the political climate, blacks were barred from flying in the U.S. Army Air Corps (the predecessor to the Air Force). In fact, they rarely entered any cockpits at all. Census records show that only a few dozen licensed black pilots lived in the entire United States prior to World War II. That number finally began to rise when several historically black colleges were included in the Civilian Pilot Training Program, which Congress created in 1939 to ensure that pilots would be available should war break out. Even then, the Air Corps remained opposed to admitting black recruits. But in 1940, Republican presidential nominee Wendell Willkie promised to desegregate the military, prompting his opponent, Democratic President Franklin D. Roosevelt, to authorize the enlistment of African American aviators, among other modest civil rights concessions aimed at keeping the black vote. On January 16, 1941, it was then announced that an all-black fighter pilot unit would be trained at the Tuskegee Institute in Alabama, a historically black college founded by Booker T. Washington.
The War Department officially established the 99th Pursuit Squadron (later renamed the 99th Fighter Squadron) on March 19, 1941, and it activated the unit three days later. Before the first cadets even arrived, the program got a publicity boost when First Lady Eleanor Roosevelt was taken up in a plane by C. Alfred “Chief” Anderson, a black aviation pioneer who served as the Tuskegee Institute’s chief flight instructor. Nonetheless, many top military officials, including the war secretary, reportedly expected the Tuskegee experiment to fail. Local whites also expressed opposition, at one point nearly initiating a race riot following a tense confrontation with an armed black military policeman. Meanwhile, about 100 whites signed a petition lamenting that the Tuskegee Army Air Field—which was built at great expense purely so that preexisting army air fields wouldn’t have to integrate—might cut off the “only outlet of expansion for white citizens of Tuskegee.”
Tuskegee airmen attending a briefing in Italy in 1945. First row (l-r): Hiram E. Man, unidentified airman, Newman C. Golden, Bertram W. Wilson Jr., Samuel W. Watts Jr., Second row (l-R): Armour G. McDemoe, Howard C. Gamble, Harry T. Steward, Jr, Earle R. Lane, Wickliffe, Wyrain T. Shell, Harold M. Morris, John E. Edwards, John H. Porter, James H. Fischer, Wyrain T. Shell. Third row (l-r): William E. "Porky" Rice, Tony Weaver, Charles L. White, George Arnold Lynch, Samuel L. Washington, Calvin J. Spann, Frank N. Wright. (Credit: Buyenlarge/Getty Images)
Tuskegee airmen attending a briefing in Italy in 1945. First row (l-r): Hiram E. Man, unidentified airman, Newman C. Golden, Bertram W. Wilson Jr., Samuel W. Watts Jr., Second row (l-R): Armour G. McDemoe, Howard C. Gamble, Harry T. Steward, Jr, Earle R. Lane, Wickliffe, Wyrain T. Shell, Harold M. Morris, John E. Edwards, John H. Porter, James H. Fischer, Wyrain T. Shell. Third row (l-r): William E. “Porky” Rice, Tony Weaver, Charles L. White, George Arnold Lynch, Samuel L. Washington, Calvin J. Spann, Frank N. Wright. (Credit: Buyenlarge/Getty Images)
Living primarily in primitive tents, the inaugural class of Tuskegee pilots studied such subjects as radio code, navigation and meteorology, while also taking to the air for more hands-on learning. Of the 13 original cadets, five made it graduation in March 1942, including Benjamin O. Davis Jr., who would eventually become the unit’s commander. More graduations quickly followed, and the program was expanded to comprise not only the 99th Fighter Squadron, but also the 100th, 301st and 302nd fighter squadrons, which together made up the 332nd Fighter Group. (Also considered Tuskegee Airmen are the black bomber pilots of the 477th Bombardment Group, as well as all support personnel.) Overall, 992 pilots completed the Tuskegee training program, nearly half of whom were then shipped overseas, where they gained fame for their unparalleled success at escorting bombers on long-range raids deep into Nazi-controlled territory. Flying some 1,600 missions and destroying over 260 enemy aircraft, the Tuskegee Airmen helped lay the foundation for President Harry S. Truman’s decision to desegregate the armed forces in 1948.

New Research Sheds Light On Swedish King’s Decapitation

The skull and crown of Erik IX. (Credit: Mikael Wallerstedt)
The skull and crown of Erik IX. (Credit: Mikael Wallerstedt)
A written medieval legend holds that Swedish King Erik IX, the patron saint of Stockholm whose likeness still adorns the city’s coat of arms, was beheaded in 1160 after being ambushed outside a church. Legends from that era are notoriously inaccurate. But this one—the main source of information about Erik’s life and death—received a credibility boost last week, when researchers announced that a modern analysis of the king’s suspected bones largely supports what appears in its pages.
Very little is known about King Erik IX of Sweden, who is also referred to as Erik Jedvardsson, Erik the Saint and Erik the Lawgiver. No surviving documents from his lifetime even mention him, and his earliest appearance in the extant literature merely reports that his remains rest in a shrine in Uppsala, Sweden, and that his daughter married Norwegian King Sverre Sigurdsson. In fact, the only detailed biographical account is a legend, written around the 1290s for the express purpose of establishing him as a saint. According to this legend, Erik ruled justly over the course of his decade-long reign, codified the laws of his kingdom, relentlessly promoted the Catholic Church at a time when many Swedes still worshipped the Norse gods and launched a religious crusade against Finland.
Like many Swedish kings in the post-Viking age, Erik met his end violently. The legend asserts that supporters of a Danish claimant to the throne surrounded an Uppsala church as Erik observed mass there on a May morning in 1160. Insisting on finishing the service, he then supposedly rode out to meet his opponents in battle, only to be thrown from his horse, repeatedly stabbed, mocked and finally beheaded. Miracles occurred afterward, the legend states, such as a fountain that popped up right where his decapitated head fell to the ground. For the next century, his descendents ruled Sweden on and off, including his son, who took power after murdering a rival in 1167. Erik’s suspected remains, meanwhile, along with a copper crown and a pair of medieval textiles, were placed in a reliquary at Uppsala Cathedral, about 40 miles north of present-day Stockholm.
Mural painting from Uppsala Cathedral depicting Erik IX. (Credit: Anders Damberg)
Mural painting from Uppsala Cathedral depicting Erik IX. (Credit: Anders Damberg)
King Erik’s reliquary has been opened numerous times since then, including once in the 1570s so that it could be melted down to help finance a war and again in 1946 so that researchers could analyze the skeleton inside. After participating in a TV documentary about All Saint’s Day in the mid-1990s, Sabine Sten, a professor of osteoarchaeology at Uppsala University’s Gotland campus, realized that more of Erik’s secrets could be unlocked with the help of modern forensic and archaeological techniques. Applying to the county administrative board and the Swedish Church, she received permission to run two days’ worth of tests in April 2014 (after which Uppsala Cathedral displayed Erik’s crown to the public for the first time).
Last week, Sten and her research team announced their results, which were published in the Swedish journal Fornvännen. As it turns out, they found virtually nothing to contradict Erik’s legend. Radiocarbon dating, for example, placed the bones to the 12th century, exactly when Erik is believed to have lived. An osteological analysis showed that the bones belonged to a 35- to 40-year-old man, Erik’s supposed age at the time of his death. A stable isotope analysis uncovered a diet rich in freshwater fish, which the devout Erik likely ate during the medieval church’s many fast days. And an assortment of hospital tests, including CT scans, confirmed that a neck vertebra had been severed consistent with decapitation, that multiple stab wounds marred the legs (which chainmail armor wouldn’t have protected), and that there were one or two healed skull wounds possibly suffered during the crusade against Finland.
n bone believed to belong to Erik IX. (Credit: Anna Kjellström)
Shin bone believed to belong to Erik IX. (Credit: Anna Kjellström)
The tests moreover found the man to be 5 feet 7 inches tall, about average height for the time, to be well nourished and powerfully built, to have no discernible medical conditions and to have significantly thicker bones than the typical 21st-century male of his age. “Medieval people were always moving and working and straining the skeleton,” Sten said in a Skype interview from Sweden. “Today, we are sitting here at the computer.” She pointed out that of the 3,600 medieval skeletons she’s examined, only 12 had a fracture caused by osteoporosis, whereas nowadays osteoporosis causes a fracture in about half of all Swedish women older than 50.
A second study, to be published later, will analyze DNA that Sten and her team extracted from three of the reliquary’s 24 bones. In so doing, they’ll be able to determine whether the three bones, including the severed vertebra, belong to the same individual and whether there are diseases present they can’t otherwise see. They may even be able to determine eye and hair color. Eventually, the researchers hope to compare the DNA with other royal DNA and to definitively confirm once and for all whether the reliquary’s bones belong to Erik, who, though considered a saint in Sweden, was never formally canonized by the pope in Rome. “It’s like doing a large jigsaw puzzle,” Sten said.
Some mysteries, however, are apt to remain. For one thing, the reliquary contains 23 bones that are seemingly King Erik’s. But it also has an extra shinbone that belongs to someone else. “We have no idea whose shinbone that is,” Sten said. It’s moreover unclear what happened to the rest of the skeleton; rib, finger, jaw, arm, foot and other bones have all gone missing, possibly having been brought to other churches as relics.

Who Was Yuan Shikai?



الثلاثاء، 22 مارس 2016

Why were American soldiers in WWI called doughboys?

Group portrait of soldiers during World War I. (Credit: PhotoQuest/Getty Images)
Group portrait of soldiers during World War I. (Credit: PhotoQuest/Getty Images)


It’s unknown exactly how U.S. service members in World War I (1914-18) came to be dubbed doughboys—the term most typically was used to refer to troops deployed to Europe as part of the American Expeditionary Forces—but there are a variety of theories about the origins of the nickname. According to one explanation, the term dates back to the Mexican War of 1846-48, when American infantrymen made long treks over dusty terrain, giving them the appearance of being covered in flour, or dough. As a variation of this account goes, the men were coated in the dust of adobe soil and as a result were called “adobes,” which morphed into “dobies” and, eventually, “doughboys.” Among other theories, according to “War Slang” by Paul Dickson the American journalist and lexicographer H.L. Mencken claimed the nickname could be traced to Continental Army soldiers who kept the piping on their uniforms white through the application of clay. When the troops got rained on the clay on their uniforms turned into “doughy blobs,” supposedly leading to the doughboy moniker.
However doughboy came into being, it was just one of the nicknames given to those who fought in the Great War. For example, “poilu” (“hairy one”) was a term for a French soldier, as a number of them had beards or mustaches, while a popular slang term for a British soldier was “Tommy,” an abbreviation of Tommy Atkins, a generic name (along the lines of John Doe) used on government forms.
America’s last World War I doughboy, Frank Buckles, died in 2011 in West Virginia at age 110. Buckles enlisted in the Army at age 16 in August 1917, four months after the U.S. entered the conflict, and drove military vehicles in France. One of 4.7 million Americans who served in the war, Buckles was buried at Arlington National Cemetery.

What is a Quaker gun?

Quaker gun near Centreville, Virginia. (Credit: Public Domain)
Quaker gun near Centreville, Virginia. (Credit: Public Domain)


Used in warfare to fake out an enemy, a Quaker gun is a dummy piece of artillery, typically constructed of wood and sometimes painted black. The term comes from the fact that Quakers, members of a religious group formally known as the Society of Friends (or Religious Society of Friends), traditionally believe in pacifism and non-violence. Quakerism began in England in the mid-1600s as a new Christian sect that rejected grandiose religious ceremonies, didn’t have clergy and held that the presence of God existed in every person. In 1682, Englishman William Penn, one of the many early Quakers who faced persecution in his homeland, arrived in America and founded the colony of Pennsylvania as a place for religious freedom. It’s uncertain exactly when the term Quaker gun originated, but one such sham weapon was employed in the Revolutionary War battle at Rugeley’s Mill in South Carolina. (The Quakers’ anti-war stance stopped them from actively participating in the American Revolution.) During that engagement, on December 4, 1780, Continental forces under the command of Colonel William Washington attacked the fortified barn where some 100 Loyalists under Colonel Henry Rugeley were holed up. When the attack failed, Washington, lacking artillery, had his soldiers construct a phony cannon from a log—and then called for Rugeley and his men to surrender or else. The ploy worked and the Loyalists gave up.
During the U.S. Civil War, Quaker guns were used as a means to make fortifications seem from a distance as if they were stronger, as well as a way to make it look like troops were occupying a certain position when in reality they’d already retreated. In one example during Union General George McClellan’s 1862 Peninsula Campaign, the Confederates placed logs made to resemble cannons at their earthworks around Centerville, Virginia, and duped Union scouts into thinking these sites were heavily fortified. As a result, McClellan delayed his troops’ .advance and the rebels escaped the area.

الأربعاء، 24 فبراير 2016

What is a broken arrow?

U.S. Navy nuclear test, Bikini Atoll, Marshall Islands. (Credit: FPG/Getty Images)
U.S. Navy nuclear test, Bikini Atoll, Marshall Islands. (Credit: FPG/Getty Images)
The military uses the term “broken arrow” to describe any incident in which a nuclear weapon is lost, stolen or inadvertently detonated. That might seem like a rare phenomenon, but records show that the United States has experienced more than 30 such close calls since the beginning of the nuclear age. Risks were particularly high during the Cold War, when bombers armed with thermonuclear weapons patrolled the skies around the clock. With so many planes in the air, a few experienced mishaps that led to crashes and unplanned bomb drops. In 1957, a 42,000-pound hydrogen bomb accidentally fell through the bomb bay doors of a B-36 bomber as it flew over New Mexico. The bomb’s non-nuclear conventional explosives detonated upon impact, killing a grazing cow and leaving behind a crater 12 feet deep. Luckily, the nuclear payload did not blow. Another famous near-disaster came in 1961, when a B-52 bomber suffered a fuel leak and exploded over Goldsboro, North Carolina. The plane broke apart and released two Mark 39 hydrogen bombs. All that prevented one of them from detonating was a single low-voltage safety switch.
Similar fail-safe measures have ensured that no broken arrow has ever resulted in a nuclear blast, but there have been a few incidents in which a weapon was lost and never found. During the Vietnam War, a plane carrying a nuclear bomb slid off the aircraft carrier Ticonderoga and disappeared in the Pacific. In 1968, the submarine Scorpion mysteriously sank with all 99 hands—and two nuclear-tipped torpedoes—off the coast of the Azores. The Soviet Union experienced a similar disaster two years later, when the nuclear submarine K-8 went down in the Bay of Biscay. All told, the combined broken arrows of the United States and Russia have left several dozen nuclear warheads lost at sea.

What was the dancing plague of 1518?

Painting of dancing plague.
Painting of dancing plague.
In July 1518, residents of the city of Strasbourg (then part of the Holy Roman Empire) were struck by a sudden and seemingly uncontrollable urge to dance. The hysteria kicked off when a woman known as Frau Troffea stepped into the street and began to silently twist, twirl and shake. She kept up her solo dance-a-thon for nearly a week, and before long, some three-dozen other Strasbourgeois had joined in. By August, the dancing epidemic had claimed as many as 400 victims. With no other explanation for the phenomenon, local physicians blamed it on “hot blood” and suggested the afflicted simply gyrate the fever away. A stage was constructed and professional dancers were brought in. The town even hired a band to provide backing music, but it wasn’t long before the marathon started to take its toll. Many dancers collapsed from sheer exhaustion. Some even died from strokes and heart attacks. The strange episode didn’t end until September, when the dancers were whisked away to a mountaintop shrine to pray for absolution.
The Strasbourg dancing plague might sound like the stuff of legend, but it’s well documented in 16th century historical records. It’s also not the only known incident of its kind. Similar manias took place in Switzerland, Germany and Holland, though few were as large—or deadly—as the one triggered in 1518.
What could have led people to dance themselves to death? According to historian John Waller, the explanation most likely concerns St. Vitus, a Catholic saint who pious 16th century Europeans believed had the power to curse people with a dancing plague. When combined with the horrors of disease and famine, both of which were tearing through Strasbourg in 1518, the St. Vitus superstition may have triggered a stress-induced hysteria that took hold of much of the city. Other theories have suggested the dancers were members of a religious cult, or even that they accidentally ingested ergot, a toxic mold that grows on damp rye and produces spasms and hallucinations.

Who were the buffalo soldiers?

buffalo soldiers
Buffalo soldiers of the 25th Infantry at Ft. Keogh, Montana. (Credit: Buyenlarge/Getty Images)
Following the U.S. Civil War, regiments of African-American men known as buffalo soldiers served on the western frontier, battling Indians and protecting settlers. The buffalo soldiers included two regiments of all-black cavalry, the 9th and 10th cavalries, formed after Congress passed legislation in 1866 that allowed African Americans to enlist in the country’s regular peacetime military. The legislation also brought about the creation of four black infantry regiments, eventually consolidated into the 24th and 25th infantries, which often fought alongside the 9th and 10th cavalries. Many of the men in these regiments, commanded primarily by white officers, were among the approximately 180,000 African Americans who served in the Union Army during the Civil War.
For more than two decades in the late 19th century, the 9th and 10th cavalries engaged in military campaigns against hostile Native Americans on the Plains and across the Southwest. These buffalo soldiers also captured horse and cattle thieves, built roads and protected the U.S. mail, stagecoaches and wagon trains, all while contending with challenging terrain, inadequate supplies and discrimination. It’s unclear exactly how the buffalo soldiers got their nickname. Archivist Walter Hill of the National Archives has reported that, according to a member of the 10th Cavalry, in 1871 the Comanche bestowed the name of an animal they revered, the buffalo, on the men of the 10th Cavalry because they were impressed with their toughness in battle. (The moniker later came to be used for the 9th Cavalry as well.) Other sources theorize the name originated with the belief of some Native Americans that the soldiers’ dark, curly, black hair resembled that of a buffalo. Whatever the case, the soldiers viewed the nickname as one of respect, and the 10th Cavalry even used a figure of a buffalo in its coat of arms.
When the Indian wars ended in the 1890s, the buffalo soldiers went on to fight in Cuba in the 1898 Spanish-American War; participate in General John J. Pershing’s 1916-1917 hunt for Mexican revolutionary Pancho Villa; and even act as rangers in Yosemite and Sequoia national parks. In 1948, President Harry Truman issued an executive order eliminating racial segregation and discrimination in America’s armed forces; the last all-black units were disbanded during the first half of the 1950s. The nation’s oldest living buffalo soldier, Mark Matthews, died in at age 111 in Washington, D.C., in 2005.

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