An allergy is an abnormally high sensitivity to an otherwise harmless foreign substance, or allergen, that leads to an exaggerated response of the natural immune defense mechanism. Allergens can be airborne substances, infectious agents, foods, contactants, or physical agents; and reactions can range from the relatively benign runny nose to severe inflammation, anaphylactic shock, and […]
Many cultures consider dragonflies sinister creatures, and a number of the common, vernacular names for the flying insects, such as "devil's needle" and "ear cutter," link them with evil or injury. In truth, dragonflies generally do not attack humans and are valued for their predatory control of harmful insect populations. Dragonflies lay eggs in or […]
As jets began flying higher and faster, the US Air Force became increasingly worried about the safety of its flight crew. Project Excelsior was initiated in 1958 to design a multi-stage parachute system that would allow a safe, controlled descent after a high-altitude ejection. In 1959 and 1960, Captain Joseph Kittinger made a series of […]
Briand was a French statesman who served as premier of France 11 times and held 26 ministerial posts between 1906 and 1932. After World War I, he emerged as a leading advocate of international peace. As foreign minister from 1925 to 1932, he was the chief architect of the Locarno Pact and the Kellogg-Briand Pact. […]
"The Divine One," Sarah Vaughan was an American jazz contralto with a vast range who worked as a soloist for much of her career. As a child, Vaughan studied piano and organ and began singing in her church choir. As a teenager, she won the famous amateur contest at Harlem's Apollo Theater and was featured […]
Perhaps the most popular and beloved of 20th-century American poets, Frost wrote of the character, people, and landscape of New England. Rooted in the New England landscape, yet deeply symbolic, his work is concerned with human tragedies and fears, the complexities of life, and the ultimate acceptance of one's burdens. Frost was awarded the Pulitzer […]
The city now known as Istanbul was founded as the Greek colony of Byzantium in the 8th century BCE. Eventually passing to Alexander the Great, it became a free city under the Romans in the 1st century CE. Emperor Constantine I made the city the seat of the Eastern Roman Empire in 330, later naming […]
The Tenerife Disaster was a passenger plane accident that resulted in the highest number of fatalities of any single accident in aviation history, excluding ground fatalities. It occurred when two Boeing 747s, a KLM flight in the midst of takeoff and a PanAm flight taxing in the opposite direction, collided at Los Rodeos Airport on […]
Established in 1972, Heaven's Gate was a cult that advocated self-renunciation, to the point of castration, as preparation for the "transition" to a new life on a spaceship, which adherents believed was trailing behind the comet Hale-Bopp. As the comet made its closest approach to Earth, 39 members of the group committed suicide. Authorities found […]