americium V.am-o-'ri-she-omN Synthetic radioactive chemical element, chemical symbol Am, atomic number 95. The fourth transuranium element discovered, it was first produced in 1944 from plutonium-239 in a nuclear reactor. The isotope americium-241 has been prepared in kilogram quan¬ tities and is used in a variety of measuring applications that utilize its gamma radiation. Its most familiar use is in household smoke detectors.
Amerindian See American Indian
Ames, Fisher (b. April 9, 1758, Dedham, Mass.—d. July 4, 1808, Dedham, Mass., U.S.) U.S. essayist and Federalist politician. He gradu¬ ated from Harvard College in 1774 and taught school for five years before turning to the law; he was admitted to the bar in 1781. Supporting the creation of a strong central government, Ames argued for ratification of the new U.S. Constitution at the Massachusetts constitutional convention. He became known for his uncompromising advocacy of the rights of property and his protective attitude toward commercial interests, which he defended in trenchant writing and commanding speech. In 1788 he defeated Samuel Adams for a seat in the first session of the U.S. House of Representatives; he was reelected three times. His eloquent support of the treaty negotiated by John Jay to preserve peace with England (1794) con¬ vinced the House to pass an enabling appropriation.
Ames, Winthrop (b. Nov. 25, 1870, North Easton, Mass., U.S.—d. Nov. 3, 1937, Boston, Mass.) U.S. theatrical producer and manager. Born into a wealthy New England family, he traveled to Europe in 1904 to study the management of 60 opera and theatre companies. After comanaging a Boston theatre, he became managing director of New York City’s New Theatre (1908-11). He founded the Little Theatre and the Booth Theatre, where he produced and directed such successful plays as The Philanderer (1913), Beggar on Horseback (1924), and a series of Gilbert and Sulli¬ van revivals (1926-29). His Snow White (1913) was the first play pro¬ duced in the U.S. especially for children.
amesha spenta \a-'mesh-9-'spen-t9\ In Zoroastrianism, any of the six divine beings (three male, three female) created by Ahura Mazda to help govern creation. They are worshiped separately, and each has a special month, festival, and flower. The most important are Asha Vahishta (“Truth”), who presides over the sacred fire and holds out the path of jus¬ tice and spiritual knowledge, and Vohu Manah (“Good Mind”), who wel¬ comes the blessed into paradise. Khshathra Vairya (“Desirable Dominion”) presides over metal, Spenta Armaiti (“Beneficent Devotion”) over earth, and Haurvatat (“Wholeness”) and Ameretat (“Immortality”) over water and plants. In later Zoroastrianism, each is opposed by a spe¬ cific archfiend.
amethyst Transparent, coarse-grained variety of quartz that is valued as a semiprecious gem for its violet colour. It contains a little more iron oxide (Fe 2 0 3 ) than any other variety of quartz, and its colour probably arises from this iron content. Heating removes the colour or changes it to the yellow of citrine; most commercial citrine is made in this manner. Notable deposits are found in Brazil, Uruguay, Ontario, and North Caro¬ lina. The birthstone for February, amethyst is usually faceted with step cuts or emerald cuts but also has been used since ancient times for carved intaglios. See photograph on opposite page.
AMEX See American Stock Exchange
Amhara Vam-'ha-raX People of the Ethiopian central highlands. The Amhara number some 18 million and compose almost three-tenths of
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Amharic ► Amis I 61
Ethiopia’s population. Their language is Amharic, a Semitic language of the Afro-Asiatic family, and their religion is Ethiopian Orthodox. The Amhara, who have dominated the history of their country, descend from ancient Semitic conquerors who mingled with indigenous Cushitic peoples. They are agriculturalists and place great value on land owner¬ ship.
Amharic \am-'ha-rik\ language Semitic language of Ethiopia. Amharic is spoken by more than 18 million people as a first language and is used as a ungua franca throughout much of central highland Ethiopia. Its status as a de facto national language is largely due to the long domi¬ nance of the Ethiopian monarchy by Amhara sovereigns. Amharic is writ¬ ten in a modified form of the partly syllabic, partly alphabetic script used to write Ge'ez, the classical language of Christian Ethiopian civilization (see Ethiopic languages). Though manuscripts in Amharic are known from the 14th century, the language has only recently been used as a general medium for literature, journalism, and education.
Amherst, Jeffery Amherst, 1st Baron (b. Jan. 29, 1717, Sev- enoaks, Kent, Eng.—d. Aug. 3, 1797, Sevenoaks) British army com¬ mander. In the French and Indian War, he took the French fort at Louisbourg, Cape Breton Island, in 1758 and was promoted to chief of command in America. In 1760 he directed the campaign that captured Quebec and Montreal, and in 1761 he quelled the Indian uprising under Pontiac. Having secured Canada for Britain, he remained there as governor-general until 1763. Returning to England, he served as com¬ mander in chief of the British army (1772-95), but his tenure was marred by failure in the war with the American colonies and by serious abuses in the army. He was created a baron in 1776 and a field marshal in 1796. Several U.S. towns and Amherst College are named for him.
Amherst Vam-orstV College Private liberal arts college in Amherst, Massachusetts, U.S., chartered in 1825. Noah Webster was one of its founders. Consistently ranked as one of the finest colleges in the U.S., it offers a wide range of courses in the humanities, social sciences, and natural sciences. Originally a men’s college, it became coeducational in 1975. It participates in an exchange program with nearby Hampshire, Mount Holyoke, and Smith colleges and the University of Massachusetts.
amicus curiae Vo-'me-kos-'kyiir-e-I, o-'ml-kos-'kyur-e-eV (Latin: “friend of the court”) One who assists a court by furnishing information or advice regarding questions of law or fact. A person (or other entity, such as a state government) who is not a party to a particular lawsuit but nevertheless has a strong interest in it may be allowed, by leave of the court, to file an amicus curiae brief, a statement of particular views on the subject matter of the lawsuit. Such briefs are often filed in cases involv¬ ing public-interest matters (e.g., entitlement programs, consumer protec¬ tion, civil rights).
Amida See Amitabha
amide \'a-,mld\ Any member of either of two classes of nitrogen- containing organic compounds related to ammonia and amines and contain¬ ing a carbonyl group (—C=0; see functional group). The first class, covalent amides are formed by replacing the hydroxyl group (—OH) of an acid with an amino group (—NR 2 , in which R may represent a hydro¬ gen atom or an organic combining group, such as methyl). Amides formed from carboxylic acids, called carboxamides, are solids except for the sim¬ plest, formamide, a liquid. They do not conduct electricity, have high boiling points, and (when liquid) are good solvents. There are no practical natural sources of simple covalent amides, but the peptides and proteins in living systems are long chains (poly¬ mers) with peptide bonds (see cova¬ lent bond), which are amide linkages. Urea is an amide with two amino groups. Commercially important covalent amides include several used as solvents; others are the sulfa drugs and nylon. The second class, ionic (salt-like) amides (see ionic bond), are made by treating a covalent amide, an amine, or ammonia with a reactive metal (e.g., sodium) and are strongly alkaline.