Daniel Defoe, engraving by M. Van der Gucht, after a portrait by J. Tav¬ erner, first half of the 18th century.
COURTESY OF THE NATIONAL PORTRAIT GALLERY, LONDON
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1880 he modeled wax figures, which were cast in bronze after his death. He was the first of the Impressionists to achieve recognition.
degree, academic Title conferred by a college or university to indi¬ cate completion of a course of study or extent of academic achievement. In medieval Europe there were only two degrees: master (a scholar of arts and grammar) and doctor (a scholar of philosophy, theology, medicine, or law). The baccalaureate, or bachelor’s degree, was originally simply a stage toward mastership. In contemporary France the baccalaureat is con¬ ferred on the completion of secondary education, the licence on comple¬ tion of a three- to four-year program of university study, the maitrise on the passing of advanced examinations, and the doctoral on completion of several years of advanced academic studies. Other contemporary degrees include the Bachelor of Arts (B.A. or A.B.) or Bachelor of Science (B.S.) degree, typically awarded after a four-year program of college study; the Master of Arts (M.A.) or Master of Science (M.S.) degree, earned after a year or two of additional study; and the Doctor of Philosophy (Ph.D.), earned after several years of post-baccalaureate study and research. In the mid-20th century the Associate of Arts degree (A. A.) began to be awarded by U.S. junior colleges. Common professional degrees are the Doctor of Jurisprudence (J.D.) and the Doctor of Medicine (M.D.). Honorary degrees are granted without regard to academic achievement.
dehydration Method of food preservation in which moisture (prima¬ rily water) is removed. Dehydration inhibits the growth of microorgan¬ isms and often reduces the bulk of food. It is an ancient practice, used by prehistoric peoples in sun-drying seeds, by North American Indians in sun-drying meat strips, and by the Japanese in drying fish and rice. It was used to prepare troop rations in World War II, and in recent decades campers and relief agencies have discovered its advantages. Commercial dehydration equipment includes tunnel dryers, kilns, and vacuum dryers. A combination of dehydration and freezing is used in the process of freeze-drying, whereby solid food remains frozen while its liquid escapes as vapour. The dairy industry is one of the largest producers of dehydrated foods, including whole milk, skim milk, and eggs.
dehydration Loss of water, almost always along with salt, from the body, caused by restricted water intake or excessive water loss. Early symptoms of water deprivation are thirst, decreased saliva, and impaired swallowing. (When more electrolytes than water are lost, osmosis pulls water into cells, and there is no thirst.) Later, tissues shrink, including the skin and eyes. Mild fever rises as plasma volume and cardiac output decrease, and perspiration decreases or stops, greatly reducing heat loss. Urine output falls, and the kidneys cannot filter wastes from the blood. Irre¬ versible shock can occur at this point. The cause of dehydration is treated first; then water and electrolytes must be given in the correct proportions.
Deinarchus See Dinarchus
Deinonychus \dl-'na-ni-k9s\ Genus of clawed theropod dinosaurs that flourished in western North America during the Early Cretaceous period (144-99 million years ago). Deinonychus walked and ran on two legs, yet its killing devices, large sickle-like talons 5 in. (13 cm) long on the sec¬ ond toe of each foot, required it to stand on one foot while slashing at its prey with the other. Its long, outstretched tail was enclosed in bundles of bony rods that grew out of the tail vertebrae, making it very rigid. About 8-13 ft (2.4-4 m) long and weighing 100-150 lbs (45-68 kg), it had a large brain and was evidently a fast, agile predator.
Deir el-Bahri See Dayr al-Bahr}
Deira Yda-re\ Anglo-Saxon kingdom, Britain. Located in the eastern part of modem Yorkshire, it stretched from the River Humber to the River Tees. Its first recorded king, Aelle, reigned from ad 560. By the last quarter of the 7th century it had been united with its neighbour Bernicia to form the kingdom of Northumbria.
Deirdre Vdir-dre, 'dar-dra\ In medieval Irish literature, the heroine of The Fate of the Sons of Usnech, the great love story (written in the 8th or 9th century) of the Ulster cycle. A Druid foretold at Deirdre’s birth that many men would die on her account, and she was raised in seclusion. A woman of great beauty, she rejected the advances of King Conor (see Conchobar), married Noisi, one of the sons of Usnech, and fled with him to Scotland. Lured back to Ireland, Noisi and his brothers were murdered, and Deirdre killed herself to avoid marrying Conor. In the 20th century the story was dramatized by William Butler Yeats and John Millington Synge.
Deism Belief in God based on reason rather than revelation or the teach¬ ing of any specific religion. A form of natural religion, Deism originated in England in the early 17th century as a rejection of orthodox Christian¬ ity. Deists asserted that reason could find evidence of God in nature and that God had created the world and then left it to operate under the natu¬ ral laws he had devised. The philosopher Edward Herbert (1583-1648) developed this view in On Truth (1624). By the late 18th century Deism was the dominant religious attitude among Europe’s educated classes; it was accepted by many upper-class Americans of the same era, including the first three U.S. presidents.
Delacour \,del-3-'kur\, Jean Theodore (b. Sept. 26, 1890, Paris, Fr.—d. Nov. 5, 1985, Los Angeles, Calif., U.S.) French-born U.S. avi- culturist. After his boyhood collection of more than 1,300 live birds was destroyed during World War I, he made expeditions worldwide and assembled a huge new collection at the Chateau de Cleres in Normandy. He bred pheasants in captivity, discovered and named many new bird and mammal species, founded the magazine L’Oiseau (1920), and wrote the standard work The Birds of French Indochina (1931). When the Germans again destroyed his aviary, he emigrated to the U.S., but he later reestab¬ lished his aviary and zoo at Cleres.
Delacroix X.de-lo-'krwaV (Ferdinand-) Eugene (-Victor) (b. April 26, 1798, Charenton-Saint-Maurice, France—d. Aug. 13, 1863, Paris) French painter. As a young man he was strongly influenced by the Roman¬ ticism of the painter Theodore Gericault and the Polish-born composer and pianist Frederic Chopin. In 1822 he exhibited the painting Dante and Vir¬ gil in Hell, a landmark in the development of French 19th-century Roman¬ ticism. In his subsequent choice of subjects, Delacroix often showed an affinity with Lord Byron and other Romantic poets of his time. His work was characterized by an uninhibited expression of energy and movement, a fascination with violence, destruction, and the more tragic aspects of life, and a sensuous use of colour. After his success at the Paris Salon, he was commissioned to decorate government buildings; he became one of the most distinguished monumental mural painters in the history of French art. He explored the new medium of lithography and in 1827 executed 17 lithographs for an edition of Faust. In 1830 he painted Liberty Leading the People to commemorate the July Revolution that brought Louis- Philippe to the French throne. His use of colour influenced the development of Impressionism.