Richthofen \'rikt- I ho-f9n\, Manfred, baron von known as the Red Baron (b. May 2, 1892, Bres¬ lau, Ger.—d. April 21, 1918, Vaux- sur-Somme, France) German World War I ace. Born to a famous and wealthy family, he began his military career in 1912 as a cavalry officer. In 1915 he transferred to the air force and in 1916 took command of a fighter group that came to be known as “Richthofen’s Flying Circus” for its decorated scarlet planes. He had been acclaimed Germany’s greatest aviation ace, credited with shooting down 80 enemy airplanes, before he himself was shot down at age 25.
Ricimer Vri-so-moA orig. Flavius Ricimer (d. Aug. 18, 472) Roman general. The son of a Visigothic prin¬ cess and a Germanic chieftain, he rose high in the Roman army, but he was barred from the imperial throne as a barbarian and instead became a kingmaker in the empire. He defeated the Vandals in Sicily and deposed the emperor Avitus for Majorian (457), who elevated him to consul. In 461 Ricimer deposed and executed Majo¬ rian and appointed Libius Severus as Western emperor. The Eastern emperor later made Anthemius ruler in the West, but Ricimer elevated Oly- brius (472) and killed Anthemius.
Rickenbacker, Eddie orig. Edward Rickenbacher (b. Oct. 8, 1890, Columbus, Ohio, U.S.—d. July 23, 1973, Zurich, Switz.) U.S. World War I ace and industrialist. He developed an early interest in auto¬ mobiles, and by the time the U.S. entered the war in 1917 he was one of the country’s top racing drivers. He began army service as a driver and soon became a fighter pilot. For shooting down 26 enemy airplanes in World War I, he was awarded the Medal of Honor. He later founded and directed his own automobile company, and from 1932 he was an execu¬ tive with several airlines. As president of Eastern Air Lines from 1938 to 1959, he oversaw its growth into a major corporation.
rickets or vitamin D deficiency Disease of infancy and childhood characterized by defective bone growth due to lack of vitamin D. Calcium phosphate is not properly deposited in the bones, which become soft, curved, and stunted. Early symptoms include restlessness, profuse sweat¬ ing, lack of limb and abdominal-muscle tone, soft skull bones, and devel¬ opmental delays. Muscles may cramp and twitch. Without early treatment, effects may include bowlegs, knock-knees, and beadiness where the ribs meet the breastbone. A narrow chest and pelvis can later increase sus¬ ceptibility to lung diseases and impede childbirth. Treatment is with high- dose vitamin D supplementation, sunlight, and a balanced diet. Adding vitamin D to milk has reduced rickets in high-latitude areas where the skin cannot produce enough.
Ricketts, Howard T(aylor) (b. Feb. 9, 1871, Findlay, Ohio, U.S.—d. May 3, 1910, Mexico City, Mex.) U.S. pathologist. He received his medi¬ cal degree from Northwestern University. He discovered the bacterium
Manfred, Freiherr (baron) von Richthofen.
PICTORIAL PARADE
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rickettsia ► Riesener I 1621
(named rickettsia) that causes Rocky Mountain spotted fever and epidemic typhus. He demonstrated in 1906 that the former could be transmitted by the bite of a certain tick and identified a bacterium in the blood of infected animals, in the ticks, and in their eggs. He found that epidemic typhus in Mexico was transmitted by a louse and found a related bacterium in the victim’s blood and in the lice. He transmitted the disease to monkeys, which developed immunity. He died of typhus later that year.
rickettsia \ri-'ket-se-3\ Any of the rod-shaped bacteria that make up the family Rickettsiaceae (named for Howard Ricketts). They are rod-shaped or variably spherical, and most are gram-negative (see gram stain). Natu¬ ral parasites of certain arthropods, they can cause serious diseases in humans and other animals, to which they are usually transmitted by a bite from an arthropod carrier. Because certain species can survive consider¬ able drying, rickettsias can also be transmitted when arthropod feces are inhaled or enter the skin through abrasion. Typhus, trench fever, and Rocky Mountain spotted fever are rickettsial infections. The most effective treat¬ ment includes timely and prolonged administration of broad-spectrum antibiotics.
Rickey, Branch (Wesley) (b. Dec. 20, 1881, Stockdale, Ohio, U.S.—d. Dec. 9, 1965, Columbia, Mo.) U.S. baseball executive. Rickey began playing professional baseball while a student at Ohio Wesleyan University. In 1917 he began a long association with the St. Louis Car¬ dinals (president, 1917-19; field manager, 1919-25; general manager, 1925^12). In 1919 he devised the farm system of training ballplayers. He later became president and general manager of the Brooklyn Dodgers (1943-50). Defying strong resistance, in 1945 he broke a long-standing race barrier by hiring the first black player in major league baseball. Jackie Robinson played for the Dodgers’ farm teams for two years before he was brought up to play as an infielder for Brooklyn in 1947. Rickey was later associated with the Pittsburgh Pirates (1950-59).
Rickover, Hyman G(eorge) (b. Jan. 27, 1900, Makov, Russia—d. July 8, 1986, Arlington, Va., U.S.) U.S. naval nuclear engineer. His fam¬ ily immigrated to the U.S. in 1906, and he grew up in Chicago. After graduating from the U.S. Naval Academy, he served on submarines and other ships, then headed the electrical section of the Navy’s Bureau of Ships in World War II. From 1947 he led the Navy’s nuclear-propulsion program; his team developed the first atomic-powered submarine, the USS Nautilus, launched in 1954. He headed research on reactor develop¬ ment for the Atomic Energy Commission and helped develop the coun¬ try’s first full-scale, civilian-use nuclear power plant, at Shippingport, Pa. (1956-57). Promoted to admiral in 1973, he was noted for his outspoken views and his singleminded advocacy of nuclear power.
Rida, Muhammad Rashid See Muhammad Rashid Rida
riddle Deliberately enigmatic or ambiguous question requiring a thoughtful and often witty answer. The riddle is a form of guessing game that has been a part of the folklore of most cultures from ancient times. Western scholars generally recognize two main kinds of riddle: the descriptive riddle, usually describing an animal, person, plant, or object in an intentionally enigmatic manner (thus an egg is “a little white house without door or window”); and the shrewd or witty question. A classical Greek example of the latter type is “What is the strongest of all things?”— “Love: iron is strong, but the blacksmith is stronger, and love can sub¬ due the blacksmith.”
Ride, Sally (Kristen) (b. May 26, 1951, Encino, Calif., U.S.) U.S. astronaut. She received a Ph.D. in physics from Stanford University in 1977 and joined NASA the same year. In 1983 she participated in the sev¬ enth space-shuttle mission, aboard the Challenger, as flight engineer, becoming the first American woman and the third woman internationally (after the Russians Valentina Tereshkova [1963], and Svetlana Savitskaya [1982]) to fly into outer space. She went on to become director of the Cali¬ fornia Space Institute at UC-San Diego in 1989. From 1999 Ride worked on Internet-based projects related to space and pursued her longtime inter¬ est in encouraging young women to study science and mathematics.
Ridgway, Matthew B(unker) (b. March 3, 1895, Fort Monroe, Va., U.S.—d. July 26, 1993, Fox Chapel, near Pittsburgh, Pa.) U.S. army officer. He graduated from West Point and served in staff positions until World War II. In 1942 he commanded an airborne division in the inva¬ sion of Sicily (1943), the first airborne assault in U.S. military history. He led his paratroopers in the Normandy Campaign and commanded airborne operations across Europe. In the Korean War he led the U.S. 8th Army,