British archaeologist and Egyptologist who made valuable contributions to the techniques and methods of field excavation and invented a sequence dating method that made possible the reconstruction of history from ...
desert area containing plant and animal fossils and archaeological sites in eastern Arizona, U.S., 19 miles (30 km) east of Holbrook. Established as a national monument in 1906 and as ...
fossil formed by the invasion of minerals into cavities between and within cells of natural wood, usually by silica (silicon dioxide, SiO2) or calcite (calcium carbonate, CaCO3). The petrified forests ...
the basis of Roman Catholic doctrine on papal primacy, resting partly on Christ's bestowing the "keys of the Kingdom" on Peter (the first pope, according to Roman Catholic tradition) and ...
Brazilian company that was founded in 1953 as a government-owned monopoly to prospect, extract, and refine domestic petroleum and to transport that oil and its derivatives. Petrobras is an operating ...
in the strictest sense, any of a large group of chemicals (as distinct from fuels) derived from petroleum and natural gas and used for a variety of commercial purposes. The ...
city, Leningrad oblast (province), northwestern Russia. It lies on the southern shore of the Gulf of Finland, 18 miles (29 km) southwest of the city of St. Petersburg. Peter I ...
major Belgian petroleum conglomerate, engaged in the exploration for and production of crude oil, oil refining, and petrochemical production. Its headquarters are in Brussels.
archaeological site featuring some 25,000 prehistoric and historic petroglyphs (rock carvings), central New Mexico, U.S. It is situated on the west side of Albuquerque, near the Rio Grande. In addition ...
state-owned Venezuelan company created through the nationalization of the petroleum industry on Jan. 1, 1976. It earns the largest share of Venezuela's foreign exchange. Its headquarters are in Caracas.
state-owned Mexican company, a producer, refiner, and distributor of oil, natural gas, and petroleum derivatives. Pemex is the largest Latin American oil company. Its headquarters are in Mexico City.
complex mixture of hydrocarbons that occur in the Earth in liquid, gaseous, or solid forms. The term is often restricted to the liquid form, commonly called crude oil, but as ...
the branch of engineering that involves the development and exploitation of crude oil and natural gas fields as well as the technical analysis and forecasting of their future performance. Its ...
field of engineering that involves the optimized development and exploitation of crude oil and natural gas fields, as well as the technical analysis and forecasting of these fields' future performance. ...
translucent, yellowish to amber or white, unctuous substance having almost no odour or taste, derived from petroleum and used principally in medicine and pharmacy as a protective dressing and as ...
subsurface reservoir of petroleum. The oil is always accompanied by water and often by natural gas; all are confined in porous rock, usually such sedimentary rocks as sands, sandstones, arkoses, ...
any wax obtained from petroleum, including paraffin wax, microcrystalline wax, and petroleum jelly (qq.v.). By comparison, animal and vegetable waxes are generally higher in cost, of varying chemical constitution, and ...
city, southwestern Pernambuco estado ("state"), northeastern Brazil. It lies on the left (north) bank of the Sao Francisco River, just across from Juazeiro, in Bahia state, with ...
scientific study of rocks that deals with their composition, texture, and structure; their occurrence and distribution; and their origin in relation to physicochemical conditions and geologic processes. It is concerned ...
pair of skyscraper office buildings in Kuala Lumpur, Malaysia, that are among the world's tallest buildings. The Twin Towers, built to house the headquarters of Petronas, the national petroleum company ...
city, northern Kazakhstan. It lies along the Esil (Ishim) River in the centre of the Esil Steppe. Petropavlovsk was founded as a Russian fort in 1752 and soon became an ...
port and administrative centre of Kamchatka oblast (region), far eastern Russia. It lies along the landlocked Avachinskaya Gulf, on the Pacific coast of the Kamchatka Peninsula. The ...
city, Hunedoara judet (county), west-central Romania, situated on a tributary of the Jiu River. Founded in the 17th century, it is the principal city and cultural centre for the upper ...
Soviet Armenian chess master who won the world championship from Mikhail Botvinnik in 1963, defended it successfully against Boris Spassky in 1966, and was defeated by Spassky in 1969. Petrosyan's ...
city and capital of Karelia, northwestern Russia, situated on the western shore of Lake Onega, south of the Shuya River outflow. The city was founded in 1703 by Peter I ...
city, central Rio de Janeiro estado (state), southeastern Brazil. It is situated in a valley at 2,667 feet (813 metres) above sea level, in the Orgaos Mountains, ...
Italian merchant and politician who succeeded in gaining supreme power over Siena. Although an absolute and tyrannical ruler, he did a great deal to augment the artistic splendour of his ...
French churchman, philosopher, and critical thinker, called Doctor facundus ("eloquent teacher"), who was important as a forerunner to William of Ockham.
Vietnamese scholar whose literary works served as a bridge between his civilization and that of the West. He helped popularize the romanized script of the Vietnamese language, Quoc-ngu.
Italian historian of religions and educator, a founder and president (1950-59) of the International Association for the Study of History of Religions. His original comparative method is shown in many ...
in modern usage, an underskirt worn by women. The petycote (probably derived from the Old French petite cote, "little coat") appeared in literature in the 15th century in reference to ...
American professional basketball player, first to score 20,000 points in the National Basketball Association (NBA). A clumsy player in high school, Pettit turned himself into a graceful 6-ft 9-in (2.06 ...
American settlement worker, remembered for her extensive work among the mountain people of Kentucky to improve health and living conditions and educational opportunities.
American stock-car racer who was the most successful driver in the history of the National Association for Stock Car Auto Racing (NASCAR). Petty won 200 NASCAR races in his career ...
English political economist and statistician whose main contribution to political economy, Treatise of Taxes and Contributions (1662), examined the role of the state in the economy and touched on the ...
American singer and songwriter whose roots-oriented guitar rock arose from the new-wave movement of the late 1970s and resulted in a string of hit singles and albums.
flowering plant whose showy, trumpet-shaped flowers make it immensely popular for summer beds and window boxes. It is a genus of the nightshade family (Solanaceae), originating in South America, and ...
town ("parish"), Chichester district, administrative county of West Sussex, historic county of Sussex, England. The parish adjoins the great park of Petworth House (now owned by the National Trust). The ...
Austrian mathematician and astronomer instrumental in the European revival of the technical understanding of the astronomical ideas of Ptolemy (fl. c. AD 140) and the early use of sines in ...
copy of a Roman map, made in 1265 by a monk of Colmar (Alsace) on 12 sheets of parchment. Eleven of the sheets are now in the Nationalbibliothek in Vienna. ...
locality, Wealden district, administrative county of East Sussex, historic county of Sussex, England. Once an English Channel port, it now lies a mile inland along a narrow waterway; from the ...
originally a raised and enclosed place in a church designed for an ecclesiastical dignitary or officer; the meaning was later extended to include special seating in the body of the ...
American industrialist brothers who expanded the Sun Oil Company (which their father had founded) by introducing new refining, marketing, and distribution techniques.
any of eight species of birds of the genus Contopus (family Tyrannidae); it is named for its call, which is monotonously repeated from an open perch. In North America a ...
any of the nodules of lymphatic cells that aggregate to form bundles or patches and occur usually only in the lowest portion (ileum) of the small intestine; they are named ...
Venezuelan soldier and politician, a leader in the country's independence movement and its first president. In the crucial early years of Venezuelan independence, he led the country as a dictator.
German controversialist-a Christianized Jew-and opponent of Jewish literature, whose dispute with the Humanist and Hebraist Johannes Reuchlin (q.v.) was a European cause celebre in the early 16th century.
city, Baden-Wurttemberg Land (state), southwestern Germany. It lies on the northern edge of the Black Forest (Schwarzwald), where the Nagold and Wurm rivers join the Enz, northwest ...
Swiss military leader, spokesman for Roman Catholic interests in the cantons, and probably the most important Swiss political figure in the latter half of the 16th century.
quantitative measure of the acidity or basicity of aqueous or other liquid solutions. The term, widely used in chemistry, biology, and agronomy, translates the values of the concentration of the ...
genus of about 200 species of white to blue or purple-flowering annual herbs, native to North America and Andean South America and including several species of garden flowers. It belongs ...
genus of trilobites (an extinct group of aquatic arthropods) found as fossils in Silurian and Devonian rocks (between 345,000,000 and 430,000,000 years old) in Europe and North America. Phacops is ...
Roman fabulist, the first writer to Latinize whole books of fables, producing free versions in iambic metre of Greek prose fables then circulating under the name of Aesop.
one of the 30 soil groups in the classification system of the Food and Agriculture Organization (FAO). Phaeozems are characterized by a humus-rich surface layer covered in the natural state ...
ancient city on the western end of the southern plain of Crete, about 3.5 miles (5.6 km) from the sea. The site was occupied from the 4th millennium BC, and ...
(Greek: "Shining," or "Radiant"), in Greek mythology, the son of Helios, the sun god, and a woman or nymph variously identified as Clymene, Prote, or Rhode. Taunted with illegitimacy, Phaethon ...
open, four-wheeled, doorless carriage, popular in the 18th and 19th centuries. It contained one or two seats, usually had a folding, or falling, top, and was owner-driven (i.e., it had ...
Tibetan family that in the 14th century liberated Tibet from Mongol control. The Phag-mo-gru had begun to extend its power over the surrounding countryside in the 13th century at a ...
process by which certain living cells called phagocytes ingest or engulf other cells or particles. The phagocyte may be a free-living one-celled organism, such as an amoeba, or one of ...
