Celsus \'sel-s9s\, Aulus Cornelius (fl. 1st century ad) Roman medi¬ cal writer. His famous treatise De medicina, a major source of knowledge of early medicine, shows that it was remarkably advanced, urging clean¬ liness and use of antiseptics, describing facial skin grafting, and stating the four cardinal signs of inflammation. The book’s three parts discuss diseases requiring diet, drug, or surgical therapy.
Celt Vkelt, 'selt\ Any member of an early Indo-European people who spread over much of Europe from the 2nd millennium to the 1st century bc. They were absorbed into the Roman Empire as Britons, Gauls, Boii, Galatians, and Celtiberians. Early archaeological evidence (c. 700 bc) comes from the Hallstatt site in Austria. People of this Iron Age culture controlled trade routes along the Rhone, Seine, Rhine, and Danube riv¬ ers. As they moved west, Hallstatt warriors introduced the use of iron, which helped them dominate other Celtic tribes. By the mid 5th century bc, the La Tene culture emerged along the Rhine and moved into eastern Europe and the British Isles. Celts sacked Rome c. 390 and raided the whole peninsula, then settled south of the Alps (Cisalpine Gaul) and men¬ aced Rome until they were defeated in 225 bc. In the Balkans, they sacked Delphi in 279 but were defeated by the Aetolians. They crossed to Ana¬
tolia and looted until they were subdued by Attalus I about 230 bc. Rome controlled Cisalpine Gaul by 192 and in 124 took territory beyond the Alps. In Transalpine Gaul, from the Rhine and the Alps west, the Celts were pressed by Germanic tribes from the west and Romans from the south. By 58 Julius Caesar had begun campaigns to annex all of Gaul. Celtic settlement of Britain and Ireland is deduced from archaeological and linguistic evidence. The Celtic social system comprised a warrior aristocracy and freemen farmers; Druids, with magico-religious duties, ranked higher than warriors. They had a mixed farming economy. Their oral literary composition was highly developed, as was their art; they manufactured gold and silver jewelry, swords and scabbards, and shields inlaid with enamel.
Celtiberia \,sel-t9- , bir-e-9\ Mountainous district, ancient Spain. Located in northeastern Spain between the Ebro and Tagus rivers, it had long been inhabited before it was occupied in the 3d century bc by tribes of mixed Iberian and Celtic stock. The Celtiberians first submitted to Rome in the early 2nd century bc but were not completely dominated until 133 bc. Exca¬ vated horse bits, daggers, and shield fittings attest to their warlike nature.
Celtic \'kel-tik\ languages Branch of the Indo-European language fam¬ ily spoken across a broad area of western and central Europe by the Celts in pre-Roman and Roman times, now confined to small coastal areas of northwestern Europe. Celtic can be divided into a continental group of languages (all extinct) and an insular group. Attestation of Insular Celtic begins around the time Continental Celtic fades from the scene as Celtic tongues gave way to Latin and other languages on the European conti¬ nent. The Insular Celtic languages are conventionally divided into Goidelic (Irish, Manx, and Scottish Gaelic) and Brythonic (Welsh, Cornish, and Breton). Traditional Cornish was supplanted by English at the end of the 18th century. Manx, spoken on the Isle of Man, expired in the 20th century with the death of the last reputed native speaker in 1974. Both Manx and Cornish have been revived by enthusiasts, though neither can be considered community languages.
Celtic religion Beliefs and practices of the ancient Celts of Gaul and the British Isles. Celtic worship centred on the interplay of the divine ele¬ ment with the natural world. Springs, rivers, and hills were thought to be inhabited by guardian spirits, usually female. Some gods were widely worshiped; lesser deities were associated with particular tribes or places. The most honoured god was Lugus, who was skilled in all the arts. Cer- nunnos was lord of the animals; the goddess of mares and fertility was called Epona (Gaul), Macha (Ireland), or Rhiannon (Britain). Goddesses often came in groups of three. The priests of Celtic religion were the Dru¬ ids; they maintained an oral tradition and left no writings. Seasonal fes¬ tivals included Samhain (November 1), which marked summer’s end and served as a feast of the dead, and Beltane (May 1). Oak trees, holly, and mistletoe were considered sacred. The Celts believed in life after death as well as transmigration of souls. See also Bran; Brigit.
cement Agent that binds concrete and mortar. Cements are finely ground powders that, when mixed with water, set to a hard mass. The cement of 2,000 years ago was a mixture of ash and lime. Volcanic ash mined near the city of Puteoli (now Pozzuoli), near Naples, was particularly rich in essential aluminosilicate minerals, giving rise to the pozzolana cement of the Roman era. See also Portland cement.
cementation In geology, the hardening and welding of clastic sedi¬ ments (those formed from preexisting rock fragments) by the precipitation of mineral matter in the pore spaces. It is the last stage in the formation of sedimentary rock. Many minerals may act as cements; the most common is silica (generally quartz), but calcite and other carbonates also occur, as do iron oxides, barite, anhydrite, zeolites, and clay minerals.
Cenis \s9-'ne\, Mount French Mont Cenis V.mc^-so-'neV Italian Moncenisio Vmon-cha-'ne-zyoX Massif and pass, Alps. Located in southeastern France west of Turin, Italy, the pass was an invasion route from earliest times and is traversed by a road 24 mi (38 km) long, built by Napoleon in 1803-10. The road climbs to Mount Cenis Pass (eleva¬ tion 6,834 ft [2,083 m]) and passes between two peaks more than 8,200 ft (2,500 m) high. The Mount Cenis railway tunnel, 8.5 mi (14 km) long, was the first great tunnel through the Alps (opened 1871). The road tun¬ nel, about 8 mi (13 km) long, opened in 1980.
Cennini \chan-'ne-ne\, Cennino (d'Andrea) (b. c. 1370, near Florence—d. c. 1440, Florence) Italian painter and writer active in Flo¬ rence. A few surviving paintings are attributed to him, but he is best known
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as the author of II libro dell’arte (1437; The Craftsman’s Handbook), the most important sourcebook on artistic practice in the late Middle Ages. His detailed descriptions of tempera and fresco painting reflect the tech¬ nical procedures of the great Florentine painting tradition. He believed that painting held a high place among occupations because it combined theory or imagination with the skill of the hand.
cenotaph Vse-no-.tafA (Greek: “empty tomb”) Monument, sometimes in the form of a tomb, to a person buried elsewhere. Ancient Greek writ¬ ings tell of many cenotaphs, none of which survives. Existing cenotaphs of this type are found in churches (e.g., in Santa Croce, Florence, where there are memorials to Dante, Niccolo Machiavelli, and Galileo). The term is now applied to national war memorials.
Cenozoic \,se-n3-'zo-ik\ Era Third of the major eras of Earth history, and the interval of time during which the continents assumed their mod¬ ern configurations and geographic positions. It was also the time when the Earth’s flora and fauna evolved toward those of the present. The Cen¬ ozoic, from the Greek for “recent life,” began c. 65 million years ago and is divided into two periods, the Tertiary (65-1.8 million years ago) and the Quaternary (1.8 million years ago to the present).
censor In ancient eastern Asia, a government official whose primary duty was to scrutinize the conduct of officials and rulers. During the Qin (221-206 bc) and Han (206 bc-ad 220) dynasties, the censor’s function was to criticize the emperor’s acts, but in later periods the censorate was expanded and became an instrument for imperial control of the bureau¬ cracy. Censors checked important documents, supervised construction projects, reviewed judicial proceedings, kept watch over state property, and looked for cases of subversion and corruption.