patio process or Mexican process Method of isolating silver from its ORE, apparently dating from pre-Columbian times. The ore was crushed and ground by mule power in arrastras, reducing it to a fine mud. This was then spread over a courtyard or patio, sprinkled with mercury, salt, and copper sulfate, and mixed by driving mules over it. Chemical reac¬ tions caused the silver to dissolve in the mercury. When the amalgam¬ ation was complete, the material was agitated with water in large tubs and the mud run off. The amalgam at the bottom was collected and heated to drive off the mercury. Used for much of the world’s silver production for 350 years, the process was replaced by the cyanide process early in the 20th century.
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1458 I Patna ► Paul III
Patna Vpot-noV City (pop., 2001 prelim.: 1,376,950), capital of Bihar state, northeastern India, on the Ganges River. It was founded in the 5th century bc as Pataliputra and was the capital of Magadha until the 1st century bc. It was ruled later by the Mauryan empire. A centre of learning, it became the Gupta dynasty’s capital in the 4th century ad but declined and was deserted by the 7th century. Revived as Patna in 1541 by an Afghan ruler, it became prosperous under the Mughal dynasty and passed to the British in 1765. Extensive archaeological excavations have been made in its vicinity.
Paton, Alan (Stewart) (b. Jan. 11, 1903, Pietermaritzburg, Natal, S.Af.—d. April 12, 1988, near Dur¬ ban) South African writer and politi¬ cal activist. While principal of a reformatory housing black youths,
Paton introduced controversial pro¬ gressive reforms and wrote his best- known work, the novel Cry, the Beloved Country (1948), focusing international attention on the issue of apartheid. To offer a nonracial alter¬ native to apartheid, he helped found the Liberal Party of South Africa in 1953 and led the organization until it was banned in 1968. His other works include the novel Too Late the Phalarope (1953) and the biogra¬ phies Hofmeyr (1964) and Apartheid and the Archbishop (1973).
patria potestas Vpa-tre-o- po-'tes-.tasV Latin "power of the father" In Roman family law, the power that the male head of a family {paterfamilias ) exercised over his descendants in the male line and over adopted children. Originally this power was absolute and included the power of life and death; a paterfa¬ milias could acknowledge, banish, kill, or disown a child. He could free his male descendants from this obligation or turn over his daughter and all her inheritance to the power of her husband. By the end of the repub¬ lic (from about the 1st century bc), a father could inflict only light pun¬ ishment and his sons could keep what they earned.
patriarch Title applied to Old Testament leaders such as Methuselah, Abraham, Isaac, and Jacob. It was once given also to some Roman Catho¬ lic bishops who wielded great authority. It is still used in Eastern Ortho¬ doxy, which now has nine patriarchates: Constantinople, Alexandria, Antioch, Jerusalem, Moscow, Georgia, Serbia, Romania, and Bulgaria.
patrician In ancient Rome, any member of a group of citizen families who, in contrast to the plebeians, formed a privileged nobility. They attempted to hold on to magistracies, priesthoods, and legal and religious knowledge, and the great civil struggle of the Roman republic was the effort of the plebeians to achieve equality and break the patrician monopoly. Gradually the patricians lost their monopoly—except in a few areas, such as selected priesthoods and the office of interrex—and in the late repub¬ lic (1st century bc) the distinction lost political importance. After 27 bc, patrician rank was necessary for ascent to the imperial throne. After Con¬ stantine’s reign (ad 337), the term became an honorary title with no par¬ ticular power.
Patrick, Saint (fl. 5th century; feast day March 17) Patron saint of Ire¬ land. Born in Britain of a Romanized family, he was captured at age 16 by Irish raiders and carried into slavery in Ireland. He spent six years as a herdsman before escaping from his master and being reunited with his family in Britain. Called in a dream to bring Christianity to the Irish, he returned to Ireland and journeyed far and wide, baptizing chiefs and kings and converting whole clans. One popular legend says that he explained the notion of the Holy Trinity using the shamrock, now the national flower of Ireland. He is also said to have rid Ireland of snakes.
patristic literature Body of literature that comprises those works (excluding the New Testament) written by Christians before the 8th cen¬ tury. It refers to the works of the Church Fathers. Most patristic literature is in Greek or Latin, but much survives in Syriac and other Middle East¬ ern languages. The works of the Apostolic Fathers contain the earliest patristic literature. By the mid-2nd century, Christians wrote to justify their faith to the Roman government and to refute Gnosticism. In the 4th
and 5th centuries, Augustine of Hippo and others laid the foundation for much of medieval and modern Christian thought. Significant patristic authors include Justin Martyr, Origen, Tertullian, Eusebius of Caesarea, Athanasius, Basil the Great, St. Gregory of Nyssa, Gregory of Nazianzus, John Chrysostom, Ambrose, Ephraem Syrus (3067-373), St. Jerome, The¬ odore of Mopsuestia, St. Cyril of Alexandria (c. 375^144), St. Maximus the Confessor (c. 580-662), and Pope Gregory I.
patron saint Saint to whose protection and intercession a person, soci¬ ety, church, place, profession, or activity is dedicated. The choice is usu¬ ally made on the basis of some real or presumed relationship (e.g., St. Patrick is the patron saint of Ireland because he is credited with introduc¬ ing Christianity there).
patronage system See spoils system
pattern recognition In computer science, the imposition of identity on input data, such as speech, images, or a stream of text, by the recog¬ nition and delineation of patterns it contains and their relationships. Stages in pattern recognition may involve measurement of the object to identify distinguishing attributes, extraction of features for the defining attributes, and comparison with known patterns to determine a match or mismatch. Pattern recognition has extensive application in astronomy, medicine, robotics, and remote sensing by satellites. See also speech recognition.
pattern making In materials processing, the first step in casting and molding processes, the making of an accurate model of the part, some¬ what oversize to allow for shrinkage of the cast material as it cools. Foundry workers then make a mold from the pattern, introduce the liquid into the mold, and remove the hardened part from the mold. The pro¬ cessing of materials in liquid form is commonly known as casting when it involves metals, glass, and ceramics; it is called molding when it involves plastics and some other nonmetallic materials. Patternmaking is a highly skilled trade learned by apprenticeship.
Patterson, Floyd (b. Jan. 4,1935, Waco, N.C., U.S.) U.S. boxer. Patter¬ son grew up in Brooklyn, N.Y. As a middleweight amateur fighter, he won the N.Y. Golden Gloves championship in 1951 and ’52 and won an Olym¬ pic gold medal in 1952. As a professional, he moved up to heavyweight and in 1956 succeeded Rocky Marciano as world heavyweight champion by knocking out Archie Moore. He lost the title to Ingemar Johansson in 1959, regained it in 1960 (becoming the first to hold the heavyweight champi¬ onship twice), and lost it again in 1962 to Sonny Liston.
Patton, George S(mith) (b. Nov. 11, 1885, San Gabriel, Calif., U.S.—d. Dec. 21, 1945, Heidelberg, Ger.) U.S. army officer. He gradu¬ ated from West Point and fought in World War I with the newly formed tank corps. He was later promoted to major general and given command of the 2nd Armored Division (1940). In World War II he led military operations in Morocco (1942) and Sicily (1943) and then commanded the 3rd Army in its sweep across northern France (1944) into Germany (1945). His strategy of bold and highly mobile operations in tank warfare, coupled with his strict, highly disciplined leadership, earned him his troops’ respect and the nickname “Old Blood-and-Guts.” Criticized for striking a hospitalized soldier he suspected of malingering, he later pub¬ licly apologized. He died in a car crash in Germany. See also Battle of the Bulge.