hand, terminal part of the forelimb in primates. The human hand consists of the wrist, palm, four fingers, and thumb. In humans and other primates, the thumb is opposable, i.e., it can be moved into a position opposite to the other four digits. Opposable thumbs make possible precise movements such as grasping small objects. In vertebrates other than humans, the primary function of the hand is locomotion; the human hand, due to the evolutionary development of bipedalism, is freed for manipulative tasks. There are 27 bones in the human hand. The wrist, which joins the hand to the forearm, contains eight cubelike bones arranged in two rows of four bones each. The metacarpus, or palm, is composed of five long metacarpal bones. Fourteen phalangeal bones constitute the four fingers and thumb (three in each finger, two in the thumb). Ligaments interconnect the bones of the hand. The bones of the digits are anchored to muscles in the hand and to muscles in the arms and shoulders, through connections to tendons, permitting a wide range of movements. Among humans, the undersides of the fingers and palms have distinctive ridges, which improve grip and can be used as identification marks.

Hand, Wayland Debs, 1907-86, folklorist, b. Auckland, New Zealand. Hand wrote Popular Beliefs and Superstitions from North Carolina (1964), which is ranked among the finest published studies of superstition. It is remarkable for its logical arrangement of material, accurate comparative information, and completeness of informant attributions. Hand also wrote two volumes of essays on folklore and literature, Humaniora (1960) and Folklore International (1967), as well as Eyes on Texas: Fifty Years of Folklore in the Southwest (1967).

Hand, Learned, 1872-1961, American jurist, b. Albany, N.Y. He received his law degree from Harvard in 1896. He was a judge of the U.S. District Court for New York's Southern District (1909-24) and of the federal Second Circuit Court of Appeals (1924-51). Often called the "tenth justice of the Supreme Court," and regarded as one of the finest jurists in American history, Hand delivered more than 2,000 opinions, and was noted especially as a defender of free speech. He is the author of The Spirit of Liberty, a collection of papers and addresses (1952), and of The Bill of Rights, a series of lectures (1958).

Black Hand, symbol and name for a criminal and terroristic secret society, and especially associated with the Mafia and the Camorra. The Black Hand flourished in Sicily in the late 19th cent., and in the United States it was especially active in New York City at the beginning of the 20th cent. It is estimated that at one time 90% of New York City's Italian population was blackmailed by letters threatening death and marked with a black hand. Famous incidents associated with the Black Hand include the murder (1890) in New Orleans of chief of police Daniel Hennessy and the shooting (1909), in Palermo, Italy, of Lt. Joseph Petrosino of the New York City police.

Art of entertaining by giving the illusion of performing impossible feats. The conjurer is an actor who combines psychology, manual dexterity, and mechanical aids to effect the desired illusion. The form was established by the medieval era, when traveling conjurers performed at fairs and in the homes of the nobility. In the 19th–20th centuries, conjuring was performed on stage by magicians such as Jean-Eugène Robert-Houdin, Harry Houdini, and Harry Blackstone. In the late 20th century magicians such as Doug Henning and David Copperfield performed colourful spectacles on television, while the postmodern team Penn and Teller offered a quieter brand of magic that emphasized irony and illusion.

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Small explosive, chemical, or gas bomb used at short range. Invented in the 15th century, it became so important that 17th-century European armies had specially trained grenade throwers, or grenadiers. After circa 1750 grenades were largely abandoned because the increasing range and accuracy of firearms had lessened opportunities for close combat. They returned to widespread use in the 20th century, when their effectiveness in World War I trench warfare made them a standard part of the combat infantryman's equipment, which they have remained. Most common is the explosive grenade, with a core of TNT or another high explosive encased in an iron jacket and a fuse that detonates it either on impact or after a brief (usually four-second) delay. Chemical and gas grenades generally burn rather than explode.

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End part of the arm, consisting of the wrist joint, palm, thumb, and fingers. The hand has great mobility and flexibility to carry out precise movements. Bipedal locomotion in humans frees the hands for grasping and manipulation. The opposable thumb allows them to pick up small items and grip objects from both sides. Dexterity in the hands and increased brain size are believed to have evolved together in humans.

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(born Jan. 27, 1872, Albany, N.Y., U.S.—died Aug. 18, 1961, New York, N.Y.) U.S. jurist. He attended Harvard University, where he studied philosophy (under William James, Josiah Royce, and George Santayana) and law; thereafter he practiced law in Albany and New York City. In 1909 he was appointed a federal district judge, and in 1924 he was elevated to the U.S. Circuit Court of Appeals, becoming chief judge in 1939. He sat in many cases after his official retirement in 1951. His 52-year tenure on the federal bench (from 1909 to his death in 1961) represents a record. Several of his decisions, especially in the antitrust suit known as the Alcoa case (1945) and in a 1950 case involving charges of communist conspiracy, are considered landmarks. Although he never reached the Supreme Court of the United States, his reputation surpasses that of all but a few who have sat there.

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Secret Serbian society formed in 1911 primarily by army officers, which used terrorist methods to promote the liberation of Serbs outside Serbia from Habsburg or Ottoman rule. It conducted propaganda campaigns, organized armed bands in Macedonia, and established revolutionary cells throughout Bosnia. Within Serbia it dominated the army and wielded tremendous influence over the government. It gained its greatest notoriety with the assassination of Archduke Francis Ferdinand in 1914. After a trial in 1917, three leaders were executed and more than 200 were imprisoned. The name also referred to several extortion rackets run by immigrant Sicilian and Italian gangsters in the Italian communities of many large U.S. cities circa 1890–1920. Local merchants and wealthy individuals would receive threatening notes printed with black hands, daggers, or other menacing symbols that demanded money on pain of death or destruction of property. It declined with the beginning of Prohibition and large-scale bootlegging.

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