Blackbeard orig. Edward Teach (b. Bristol?, Eng.—d. Nov. 22, 1718, Ocracoke Island, North Carolina) English pirate. He was probably a privateer in the West Indies until 1716. With his 40-gun warship, he preyed on shipping off the Virginia and Carolina coasts, sharing his prizes with the governor of the North Carolina colony in return for protection. He was eventually killed by a British naval force, and his head, with its great black beard, was affixed to the end of his bowsprit. According to legend, he left a great buried treasure; it has never been found and prob¬ ably never existed.
blackberry Usually prickly, fruit-bearing bush of the genus Rubus, in the rose family, native chiefly to northern temperate regions. The blackberry is abundant in eastern North America and on the Pacific coast; in Europe it is common in thickets and hedges. Its usually bien¬ nial, prickly, and erect, semierect, or trailing stems bear leaves with usu¬ ally three or five oval, coarsely toothed, stalked leaflets; white, pink, or red flowers in terminal clusters; and black or red-purple aggregate fruits. The several trailing species are commonly called dewberries.
Blackberries are a fairly good source of iron and vitamin C.
blackbird In the New World, any of several species of songbirds in the family Icteridae, collectively called icterids; also, an Old World thrush (Turdus merula, family Turdidae). The best known icterid is the red¬ winged blackbird ( Agelaius phoeniceus ), which ranges from Canada to the West Indies and Central America. It is 8 in. (20 cm) long, and the male’s black plumage is set off by red shoulder patches. The Old World blackbird, 10 in. (25 cm) long, is common in woods and gardens throughout temperate Eurasia as well as in Australia and New Zealand. See also grackle.
Blackberry (Rubus).
DEREK FELL
© 2006 Encyclopaedia Britannica, Inc.
blackbody ► Blackwell I 229
blackbody Theoretical surface that absorbs all radiant energy that falls on it, and radiates electromagnetic energy at all frequencies, from radio waves to gamma RAYS, with an intensity distribution dependent on its tem¬ perature. Because all visible light falling on such a surface is absorbed without reflection, the surface will appear black as long as its tempera¬ ture is such that its emission peak is not in the visible portion of the spec¬ trum. See also absorption.
blackcap Common warbler (Sylvia atricapilla, family Sylviidae) from Europe and North Africa to central Asia. It is about 6 in. (14 cm) long and has brownish upper parts, gray underparts and face, and a black (male) or reddish brown (female) crown. Common in woodland bor¬ ders and rough hedges, it has a rich song.
Blackett \'blak-ot\ (of Chelsea),
Patrick M(aynard) S(tuart),
Baron (b. Nov. 18, 1897, London,
Eng.—d. July 13, 1974, London)
British physicist. He graduated from the University of Cambridge in 1921 and spent 10 years at the Cavendish Laboratory, where he developed the Wilson cloud chamber into an instru¬ ment for the study of cosmic radia¬ tion. He was awarded a 1948 Nobel Prize for his discoveries and was made a life peer in 1969.
blackfly Any member of the insect family Simuliidae, comprising 300 species of small, humpbacked dipter- ans found worldwide. Usually black or dark gray, the blackfly has short mouthparts adapted for sucking blood. The females bite and are sometimes abundant enough to kill chickens and even cattle. Some spe¬ cies carry worms capable of causing human disease, including river blind¬ ness. In subarctic regions blackflies may be so numerous that human habitation is impossible.
Blackfoot or Blackfeet Group of ALGONQUiAN-speaking Indian peoples in Alberta, Can., and Montana, U.S., comprising the Piegan (Pikuni or Blackfeet), the North Piegan Pikuni, the Blood (Kainai), and the Blackfoot proper (Siksika). Together they are referred to as Siksika, or Blackfoot, a name thought to have derived from the discoloration of moccasins with ashes. They were among the first Algonquians to move westward from timberland to open grass¬ land and, later, among the first to acquire horses and firearms. They were known as the strongest and most aggressive military power on the north¬ western plains. At the height of their power, in the first half of the 19th century, they held a vast territory extending from northern Saskatchewan to southwestern Montana. Each group was subdivided into hunting bands led by one or more chiefs. These bands wintered separately but came together in summer to celebrate the sun dance. For three decades begin¬ ning in 1806, the Blackfoot prevented white men from settling in their territory. They signed their first treaty with the U.S. in 1855, after which they were forced into farming and cattle raising. Some 10,000 Blackfoot live in Canada, and more than 27,000 claimed sole Blackfoot descent in the 2000 U.S. census, although only 15,000 U.S. Blackfoot are enrolled members. See photograph opposite.
blackjack or twenty-one Card game whose object is to be dealt cards having a higher count than those of the dealer, up to but not exceed¬ ing 21. The dealer may use a single deck of 52 cards or two or more decks from a holder called a shoe. Aces count as 1 or 11, and face cards as 10. Depending on the rules used, bets may be placed before the deal, after each player has been dealt one card facedown, or after each player has received two cards facedown and the dealer has exposed one of his cards.
blackmail See extortion
Blackmun, Harry (b. Nov. 12, 1908, Nashville, Ill., U.S.—d. March 4, 1999, Arlington, Va.) U.S. jurist. He received his law degree from Har¬ vard (1932) and taught law at the St. Paul College of Law (1935-41) while advancing to general partner in a Minnesota law firm. After serving as resident counsel to the Mayo Clinic (1950-59), he was appointed to the Eighth U.S. Circuit Court of Appeals. In 1970 Pres. Richard Nixon named him to the Supreme Court of the United States, where he served until 1994. Perceived as a conservative when he began his Supreme Court service, Blackmun became increasingly liberal over the years. He wrote the major¬ ity decision in Roe v. Wade (1973).
blackpoll warbler Species (Dendroica striata) of wood warbler. Like all wood warblers, it is a small, active bird that feeds on insects and has a short thin bill. A common species, it is less striking than many other wood warblers, which are known for their brightly coloured plumage.
Blackshirts Italian Camicie Nere Armed squads of Italian Fascists under Benito Mussolini who wore black shirts as part of their uniform. The squads, first organized in 1919, targeted socialists, communists, republi¬ cans, and others. Hundreds of people were killed as the squads grew in number. In 1922 Blackshirts from all over Italy participated in the March on Rome (see Rome, March on). In 1923 the private Blackshirts were offi¬ cially transformed into a national militia. With Mussolini’s fall in 1943, the Blackshirts fell into disgrace.
Blackstone, Sir William (b. July 10, 1723, London, Eng.—d. Feb. 14, 1780, Wallingford, Oxfordshire) British jurist. Orphaned at age 12, he was educated at public school and later at Pembroke College, Oxford, at the expense of his uncle, a London surgeon. He was elected a fellow of All Souls College in 1744, and in 1746 he became a barrister. Having taken a doctorate in civil law in 1750, he abandoned his legal practice in 1753 to concentrate on teaching and legal work around Oxford. He gave the first university lectures on English common law, publishing a synopsis for students in 1756. He was elected to the first chair in common law, the Vinerian professorship at Oxford, in 1758. His classic Commentaries on the Laws of England (1765—69) is the best-known description of the doc¬ trines of English law; it became the basis of university legal education in England and North America. He also served as a member of Parliament (1761-70), as solicitor general to the queen (from 1763), and as judge of the Court of Common Pleas (1770-80).