Tres Marías, Las, archipelago, in the Pacific Ocean, c.60 mi (100 km) W of Nayarit state, Mexico. Of the four islands, two—María Madre, which is the largest (c.56 sq mi/145 sq km) and is also a federal penal colony, and María Magdalena—produce maguey, salt, and lumber.

Moréas, Jean, 1856-1910, French poet, b. Athens. His name was originally Iannis Papadiamantopoulos. He went to Paris in 1872. He wrote two volumes of symbolist verse, Les Syrtes (1884) and Le Pèlerin passionné (1891). With the publication of Enone au clair visage (1894) and Eriphyle (1894), Moréas returned to classical style, and in Les Stances (1899-1901) and his play Iphigénie (1903) he clearly reacted against the new movements in poetry.

Jochumsson, Matthías, 1835-1920, Icelandic playwright, poet, and translator. Although Jochumsson was the founder of the modern drama in Iceland, with poetic plays such as Útilegumennirnir [the outlaws] (1864), he is best known as a lyric poet. After graduating from theological school he traveled abroad, returning to Iceland to work as a translator of Shakespeare, Byron, and Ibsen. His autobiography, Sögukaflar af sjálfum mér [stories from my life], was published in 1922. Jochumsson also composed hymns, including the Icelandic national hymn.

Gálvez, Matías de, 1717-84, Spanish colonial administrator, captain general of Guatemala (1779), viceroy of New Spain (1783-84); brother of José de Gálvez. He was succeeded as viceroy by his son, Bernardo de Gálvez.

Chávez Frías, Hugo Rafael, 1954-, Venezuelan political leader, president of Venezuela (1999-). Educated at the Military Academy of Venezuela (grad. 1975), for two decades he was a career army officer, rising to the rank of lieutenant colonel. In 1992, Chávez took part in an unsuccessful coup attempt against President Carlos Andrés Pérez and was imprisoned until 1994. A charismatic populist, he became the leader of the leftist Patriotic Pole alliance. Promising a peaceful social revolution, Chávez was elected president in a 1998 landslide. In office he ended the privatization of Venezuela's state holdings, put himself in control of economic matters, and cut oil production to raise oil prices. A constituent assembly mainly made up of his supporters wrote a new constitution that granted the president increased powers and a longer possible term of office and weakened the legislature and judiciary. Chávez's popularity with the country's poor increased as he took measures against rampant corruption, criticized the traditional oligarchy, and made more funds available for social programs. He also attacked his critics in business and the media and expanded the role of the military; closer ties were established with Middle Eastern oil-producing nations and Cuba.

In 2000, Chávez won office under the new constitution. Despite his populist rhetoric, many expressed fears that he was exhibiting the distinctively dictatorial signs of the classic Latin American military strongman, the caudillo. Although he retains strong support among the lower classes, opposition to his rule increased, and strikes and demonstrations sparked by his attempts to assert control over the state oil company led to a short-lived coup in Apr., 2002, and a prolonged strike by oil workers late in 2002. An attempt by the opposition to recall him through a referendum (Aug., 2004) resulted in a solid vote for Chávez. Reelected in a landslide in 2006, he moved to nationalize all private energy and power companies in Venezuela and the country's largest telecommunications firm. Internationally Chávez has called for Latin American nations to forge closer ties and achieve greater regional integration, and to be less dependent on the United States, but his outspokenness and support for potential political allies in other countries has led a number of Latin American nations to accuse him of meddling in their internal affairs.

Carías Andino, Tiburcio, 1876-1969, president of Honduras (1933-49). A strong-handed dictator, his term was twice extended by congress. Some improvements were made in communication and education. After Carías announced his retirement in 1948, presidential elections were held. Juan Manuel Gálvez, the government candidate, won easily.

Calles, Plutarco Elías, 1877-1945, Mexican statesman, president (1924-28). In 1913 he left schoolteaching to fight with Álvaro Obregón and Venustiano Carranza against Victoriano Huerta. In 1920 he joined Obregón and Adolfo de la Huerta in the rebellion against Carranza. After Obregón's term as president, Calles, who had been a cabinet member, became the presidential nominee. Adolfo de la Huerta, claiming election fraud, revolted (Dec., 1923), but Obregón and Calles established their supremacy by force (1924); Calles became president.

Calles's administration was noted for its revolutionary zeal, which often precipitated violence. At the outset agrarian reform was pursued vigorously but recklessly. Many rural schools were built, although teachers were still scarce and underpaid. Material improvements were given special attention; vast road-building and irrigation projects were undertaken. The struggle between church and state reached a new level of bitterness. In 1926 the enforcement of anticlerical legislation provoked violence; in 1926-29 the Cristeros, largely peasant rebels whose slogan was "Viva Cristo Rey" [long live Christ the King] took up arms in the states of Colima, Jalisco, and Michoacán. Military chieftains reciprocated by victimizing innocent Roman Catholics, and government officials used the strife to political advantage. At the same time legislation over land and petroleum rights brought about a serious dispute with the United States; relations between the two countries improved when Dwight W. Morrow was appointed (1927) ambassador, and the oil question was temporarily settled.

Calles created and directed a powerful national army and dissolved the private militia that threatened internal peace. He unified the government and molded the National Revolutionary party into the dominant force in Mexican politics. Calles rapidly lost his radicalism when he gained power and became a landowner and financier; he moved toward dictatorship. Already in control of the labor movement, he made himself the force behind the Callistas, a circle of financiers and industrialists who dominated the country's economy and politics. Thus he became undisputed Jefe Máximo, or political chieftain, of Mexico.

When Obregón was assassinated (1928) after his reelection to the presidency, Calles appointed Emilio Portes Gil. In 1930 he declared the agrarian reform program a failure. In the same year he engineered the election of Pascual Ortiz Rubio. Two years later he removed him to appoint Gen. Abelardo Luján Rodríguez. The mighty labor union, CROM (see Lombardo Toledano, Vicente), was smashed. The conflict with the church, temporarily subdued (1929) by Morrow, was resumed; priests were openly persecuted. Communist unions, previously used by Calles in his campaign against the CROM, were ruthlessly suppressed, and a Callista-backed fascist organization, the Gold Shirts, harassed minority groups. As the new champion of conservatism, Calles in 1935 openly opposed the policies of his former protégé, Lázaro Cárdenas, but was defeated in the contest; in 1936 he was exiled. He was allowed to return under an amnesty in 1941.

As Salamiya, town (1988 est. pop. 47,000), W central Syria. It is a transportation center situated in a fertile plain where cereals, vegetables, and cotton are grown. As Salamiya was conquered by the Arabs in the 7th cent. and built up under the early Abbasid caliphate. The Ismailis chose the town as their center c.860. It was later destroyed (903) by the Karmathians and then came under Fatimid control. Taken by the Ottoman Empire in the 16th cent., the town declined until it was resettled by Ismailis in the 19th cent. The name also appears as Selemiya.

As, symbol for the element arsenic.

Abu al-Abbas as-Saffah, d. 754, 1st Abbasid caliph (749-54). Raised to the caliphate by the armed might of Abu Muslim, he took the reign name as-Saffah [shedder of blood]. Most of the Umayyad family was exterminated, and the reign was one of massacre and force. He was succeeded by his brother al-Mansur.

Harmful effects of arsenic compounds (in pesticides, chemotherapy drugs, paints, etc.), most often from insecticide exposure. Susceptibility varies. Arsenic is believed to combine with certain enzymes, interfering with cellular metabolism. Symptoms of acute arsenic poisoning include nausea and abdominal pain followed by circulatory collapse. Acute exposure to the gas arsine causes destruction of red blood cells and kidney damage; chronic exposure causes weakness, skin disorders, anemia, and nervous-system disorders. Arsenic in urine and hair or nails is the key to diagnosis. Treatment involves washing out the stomach and promptly administering the antidote dimercaprol.

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Nonmetallic to semimetallic chemical element, chemical symbol As, atomic number 33. It exists uncombined in two stable (and several unstable) allotropes, one gray and one yellow, but is more often found in nature as the sulfide or oxide. The elemental form is used to form alloys of metals (especially lead), and certain semiconductors are made from crystals of gallium arsenide (GaAs). Arsenious oxide (arsenic trioxide or white arsenic, As₂O₃) is used in pesticides, as a pigment, and as a preservative of hides and wood; this is the poisonous “arsenic” (see arsenic poisoning) in detective stories. Arsenic pentoxide (As₂O₅) is also used in insecticides, herbicides, metal adhesives, and pigments.

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