blister beetle Any of approximately 2,000 species of beetles (family Meloidae) that secrete an irritating substance, cantharidin, which is used medically as a topical skin irritant to remove warts. In the past, canthari¬ din was often used to induce blisters, a common remedy for many ail¬ ments, and the dried remains of Spanish fly ( Lytta vesicatoria ) were a major ingredient in so-called love potions. Adult blister beetles, which are often brightly coloured, range between 0.1 and 0.8 in. (3-20 mm) in length. Blister beetles are both helpful and harmful to humans; the lar¬ vae eat grasshopper eggs, but the adults destroy crops.
blister rust Any of several diseases of pines, caused by rust fungi (see fungus) of the genus Cronartium. Blister rust affects sapwood (see wood) and inner bark and produces external blisters from which additional spores of the fungus are released and resin oozes, forming characteristic hard¬ ened masses on the trunk. It affects pines of all ages and sizes, retarding growth and weakening stems as it spreads along the trunk, sometimes killing the tree; young trees are killed more quickly than older ones. Mea¬ sures taken to fight blister rust include growing resistant varieties, destroy¬ ing nearby alternative host plants, observing strict sanitation measures, and spraying with fungicides.
blitzkrieg Vblits-,kreg\ (German: “lightning war”) Military tactic used by Germany in World War II, designed to create psychological shock and resultant disorganization in enemy forces through the use of surprise, speed, and superiority in materiel or firepower. The Germans tested the blitzkrieg during the Spanish Civil War in 1938 and against Poland in 1939, and used it in the successful invasions of Belgium, the Netherlands, and France in 1940. The German blitzkrieg coordinated land and air attacks— using tanks, dive-bombers, and motorized artillery—to paralyze the enemy principally by disabling its communications and coordination capacities.
Blitzstein Vblit-.stlnV Marc (b. March 2, 1905, Philadelphia, Pa., U.S.—d. Jan. 22, 1964, Fort-de-France, Martinique) U.S. composer. He studied at the Curtis Institute, then with the conductor Nadia Boulanger in Paris and the composer Arnold Schoenberg in Berlin. His best-known works were for the theatre: The Cradle Will Rock (1937), the circum¬ stances of whose production by Orson Welles and John Houseman became legendary; the opera Regina (1949); and his English adaptation of Bertolt Brecht and Kurt Weill’s The Threepenny Opera (1952), which became a Broadway hit. He was working on a Metropolitan Opera commission for an opera about the Sacco-Vanzetti case when he was murdered.
Blobel, Gunter (b. May 21, 1936, Waltersdorf, Silesia, Ger.) U.S. cel¬ lular and molecular biologist. He earned his M.D. from Eberhard-Karl University and his Ph.D. from the University of Wisconsin. Working in collaboration with other research groups, Blobel showed that each pro¬ tein carries a signal sequence that directs it to the proper location inside the cell. He also concluded that proteins enter organelles through a pore¬ like channel that opens in the organelle’s outer membrane when the cor¬ rect protein arrives at the organelle. For his work, Blobel was awarded a Nobel Prize in 1999. His research shed light on such hereditary diseases as cystic fibrosis and provided the basis for bioengineered drugs, includ¬ ing INSULIN.
Bloc National Vblok-nas-yo-'naU Right-wing coalition that controlled the French government from 1919 to 1924. On a wave of nationalist sen¬ timent at the end of World War I, the Bloc gained about 75% of the seats in the French Chamber of Deputies in the 1919 elections. The government tried to ensure French security against Germany through a strict enforce¬ ment of the Treaty of Versailles. Its leaders, including Raymond Poincare,
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234 I Bloch ► bloodhound
supported the Ruhr occupation (1923) to force Germany to pay reparations. It gradually lost public support, and it was defeated in the 1924 elections.
Bloch VblokA, Ernest (b. July 24, 1880, Geneva, Switz.—d. July 15, 1959, Portland, Ore., U.S.) Swiss-born U.S. composer. He conducted and lectured at the Geneva Conservatory before moving in 1916 to the U.S., where he served as director of the San Francisco Conservatory (1925-30) and taught at the University of California, Berkeley (1942-52). He worked in tonal, atonal, and serialist idioms (see also tonality; atonality; serialism); his works, many of them inspired by Jewish themes, include the opera Macbeth (1910), Schelomo for cello and orchestra (1916), the large choral works America (1926) and Avodath hakodesh (1933), and a violin concerto (1938).
Bloch Vblak\, Felix (b. Oct. 23,1905, Zurich, Switz.—d. Sept. 10, 1983, Zurich) Swiss-born U.S. physicist. He emigrated to the U.S. in 1933 and taught at Stanford University (1934-71). He worked on atomic energy at Los Alamos and on radar countermeasures at Harvard University during World War II. In 1954 he became the first director general of CERN. For developing the nuclear magnetic resonance method of measuring the mag¬ netic fields of atomic nuclei, he shared with Edward Purcell (1912—97) the 1952 Nobel Prize for Physics.
Bloch Vblok\, Marc (Leopold Benjamin) (b. July 6, 1886, Lyon, France—d. June 16, 1944, near Lyon) French historian. He served in the French infantry in World War I. From 1919 he taught medieval history at the University of Strasbourg, where he cofounded the important periodi¬ cal Annales d’histoire economique et sociale. He taught economic history at the Sorbonne from 1936. During World War II he joined the French Resistance and was captured and killed by the Germans. Among his major works are The Royal Touch (1924), French Rural History (1931), and Feudal Society (1939). As the founder of the Annales school of histori¬ ography, with its wide-ranging, interdisciplinary approach, Bloch exerted a huge influence on the study of history.
block and tackle Combination of pulleys with a rope or cable, com¬ monly used to augment pulling force. Two or more of the pulleys are attached to a fixed block, and the remaining pulleys are free to move as well as rotate. A block and tackle can be used to lift heavy weights or to exert large forces in any direction. Higher force ratios may be obtained by the use of more pulleys, but this advantage may be offset by increased friction.
Block Island Island, Rhode Island, U.S. It lies at the eastern entrance to Long Island Sound, 9 mi (15 km) southwest of Point Judith, R.I. It has an area of about 11 sq mi (29 sq km) and is coextensive with the town of New Shoreham (pop., 2000: 1,010). Called Manisses by its original Indian inhabitants. Block Island (named for the Dutch explorer Adriaen Block) received its first European settlers in 1661 and was admitted to the colony of Rhode Island in 1664. Once dependent on fishing and farming, it is now primarily a resort.
block mill Earliest mechanized factory for mass production. It was con¬ ceived by Samuel Bentham, with machinery designed by Marc Brunel and built by Henry Maudslay, and built at England’s Portsmouth naval dock¬ yard. By 1805 it was producing 130,000 pulley blocks per year. It remained in production for over 100 years. See also American System of MANUFACTURE.
blockade Act of war whereby one party blocks entry to or departure from an enemy area, often a coast. Blockades are regulated by interna¬ tional law and custom, which require advance warning to neutral states and impartial application. Penalties for breach of blockade are seizure of ship and cargo and their possible condemnation as lawful prizes. Neutral ships may not be destroyed for blockade running.
Bloemfontein Vblum-.fan-.tanN City (pop., 2005 est.: 379,000), judi¬ cial capital of the Republic of South Africa. It is also the capital of Free State province. Founded in 1846 as a fort, it became the seat of the British-administered Orange River Sovereignty (1848-54) and later that of Orange Free State, an independent Boer republic formed in 1854. The failure of the Bloemfontein Conference (1899) resulted in the outbreak of the South African War. In the 20th century the city became a geographi¬ cal transportation hub. Bloemfontein became part of the Mangaung Local Municipality in 2000. See also Pretoria; Cape Town.