croup \'krup\ Acute laryngeal inflammation and spasms in young chil¬ dren, with harsh cough, hoarseness, and difficulty breathing. Causes include infection, allergy, and physical irritation of the larynx. Viral croup, the most common, usually occurs before age 3. It can usually be treated at home with a cool mist vaporizer. Bacterial croup (epiglottitis) gener¬ ally strikes between ages 3 and 7. Swelling of the epiglottis rapidly causes severe breathing and swallowing difficulty, requiring antibiotics and inser¬ tion of a breathing tube.
Crow North American Plains Indian people of southern Montana, U.S. The Crow, whose language belongs to the Siouan language stock, were histori¬ cally affiliated with the Hidatsa. Historically, they occupied the area around the Yellowstone River in northern Wyoming and southern Montana. Much of Crow life revolved around the buffalo and the horse. The Crow were prominent as middleman traders, trading horses, bows, and other items to local village Indians in return for guns and metal goods that they carried to the Shoshone in Idaho. The basic element in Crow religious life was the supernatural vision, induced by fasting and isolation. The Crow continually suffered losses from wars with the Blackfoot and Sioux and sided with the whites in the Indian wars of the 1860s and ’70s. In 1868 they accepted a reservation carved from former tribal lands in southern Montana. Some 9,100 individuals claimed sole Crow descent in the 2000 U.S. census.
crow Any of more than 20 species of black perching birds (see passe¬ rine) of the genus Corvus (family Corvidae) that are smaller than most ravens and have a thinner bill. They are named for the sound of their call.
Common crows are found in North America and Eurasia. They eat grain, berries, insects, carrion, and the eggs of other birds. Crows may damage grain crops, but they also eat many economically harmful insects. At times tens of thousands roost together, but most species do not nest in colonies. Crows are considered the most intelligent of all birds (tool use is documented), and pet crows can be taught to imitate speech.
Crowe Vkro\, Sir Eyre (Alexander Barby Wichart) (b. July 30, 1864, Leipzig, Ger.—d. April 28, 1925, Swanage, Dorset, Eng.) British diplomat. In the years before World War I he strongly urged an anti- German policy, arguing in a 1907 memorandum that Germany aimed at the domination of Europe, that concessions would only increase its appe¬ tite for power, and that the entente with France must not be abandoned. On July 25, 1914, he urged a show of force by the British navy to fore¬ stall war, and when war began a few days later he induced the govern¬ ment to seize German vessels in British ports. He served as permanent undersecretary of state for foreign affairs (1920-25).
crowfoot See buttercup
crown gall Disease of plants caused by the bacterium Agrobacterium tumefaciens. Thousands of plant species are susceptible, including espe¬
cially rose, grape, pome and stone fruits (e.g., apples, peaches), shade and nut trees, many shrubs and vines, and perennial garden plants. Symptoms include roundish, rough-surfaced galls, several inches or more in diam¬ eter. At first cream-coloured or greenish, they later turn brown or black. As the disease progresses, affected plants lose vigour and may eventually die.
crown jewels Ornaments used at the coronation of a monarch and the formal ensigns of monarchy worn or carried on state occasions, as well as collections of personal jewelry consolidated by European sovereigns as valuable assets of their royal houses and the offices they filled. Most familiar are those of Britain, which include St. Edward’s Crown, the Royal Sceptre (with the Star of Africa diamond), the Sceptre of Equity and Mercy, and the Sword of Offering, as well as the coronation ring, anointing spoon, ampulla (flask), and coronation bracelets. Many collec¬ tions of royal jewelry have been assembled, confiscated, and dispersed over the centuries.
crown-of-thorns starfish Reddish and heavy-spined starfish ( Acan- thaster planci) that has 12-19 arms and is often 18 in. (45 cm) across. It feeds on the polyps of coral. Begin¬ ning c. 1963, its population on Aus¬ tralia’s Great Barrier Reef exploded.
Destruction of coral reefs and islands was feared, and intensive efforts were made to kill it off. Since then other outbreaks have been recorded throughout the southern Pacific. The cause of the outbreaks is unknown, but several factors have been pro¬ posed, such as the decimation of the starfish’s chief predator, the Pacific triton (a marine snail), by shell col¬ lectors. Other factors, including the runoff of nutrient-rich soil into reef waters as a result of shorefront devel¬ opment, have also been implicated. Population fluctuations could also be a feature of the starfish’s natural ecology, and human influence may alter these cycles.
crown vetch Vigorous trailing legume ( Coronilla varia), native to the Mediterranean but widely grown in temperate areas as a ground cover. It has femlike leaves and clusters of white to pink flowers. The sturdy roots are useful in binding the soil of steep slopes and roadside embankments. As a legume, crown vetch draws nitrogen from the air, trapping it in the roots, and thus improves soil fertility. It dies back to the crown each fall in cold areas, resuming growth in spring. Cutting the plant back in the fall or early spring encourages quick growth.
crucible Vkrii-so-balN Pot of clay or other refractory material, used from ancient times as a container for melting metals or other materials. Mod¬ em crucibles may be small laboratory utensils for conducting high- temperature chemical reactions and analyses, or large industrial vessels for melting and calcining metal, ore, or glass, and may be made of clay, graphite, porcelain, or a relatively infusible metal.
crucible process Technique for producing cast or tool steel. It was invented in Britain c. 1740 by Benjamin Huntsman, who heated small pieces of carbon steel in a closed fireclay crucible placed in a coke fire. This was the first process used in Europe in which the temperature (2,900°F, or 1,600°C) was high enough to melt the steel, producing a homogeneous metal of uniform composition. After 1870 the Siemens regenerative gas furnace replaced the coke-fired furnace. Capable of pro¬ ducing even higher temperatures, the Siemens furnace had a number of combustion holes, each holding several crucibles, and heated as many as 100 crucibles at a time. All high-quality tool steel and high-speed steel was long made by the crucible process. In the 20th century the electric furnace has replaced it in countries with inexpensive electric power. See also WOOTZ.
crucifixion Method of capital punishment among the Persians, Seleucids, Jews, Carthaginians, and Romans from about the 6th century bc to the 4th century ad. The condemned man was usually whipped and forced to drag the crossbeam to where the upright was standing. His hands were tied or nailed to the crossbeam, which was attached to the upright 9-12 ft (2.5- 3.5 m) above the ground, and his feet bound or nailed to the upright. Death was by heart failure or asphyxiation. Political or religious agitators and those without civil rights were crucified. Its overwhelming association
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crude oil ► Cruz I 489
today is with Jesus. Crucifixion was abolished by Constantine I in ad 337 after his conversion to Christianity. See also stigmata.
crude oil See petroleum
Cruikshank, George (b. Sept. 27, 1792, London, Eng.—d. Feb. 1, 1878, London) English painter, illus¬ trator, and caricaturist. His series of political caricatures for The Scourge (1811-16) established him as the leading political cartoonist of his generation, and he continued to sati¬ rize the policies of the Tories and Whigs in political cartoons until c.
In the 1820s and ’30s he pro¬ duced book illustrations, notably for Charles Dickens’s Sketches by “Boz”