OPUNTIA 33 ORANG OUTANG edge of the principles of the profession, which may have been gained either in a recogrnized school, or by employment un- der a practitioner of the profession, and a certain amount of high school work. Some colleges, notably Columbia, Cali- fornia, and Ohio State University, as well as the Rochester Athenium and Me- chanics Institute, give training for this work, and schools teaching this subject alone have been established in Boston, New York, and Philadelphia. Test cards of graduated letters, cases of assorted lenses, and specially designed instruments, usually reflectors or refrac- tors of light, are used in making the tests, the instruments having the widest use being the skiascope, the ophthalmom- eter, the ophthalmoscope, and the phoro- meter. Various test lenses are placed before the eye which is being tested, until the lens which best corrects a certain de- termined defect is secured. OPUNTIA, in botany, Indian fig; the typical genus of the family Opuntidx. The stem consists of flat joints broader above than below, at length becoming cylindrical and continuous. All the spe- cies were originally American. O. vul- garis is indigenous in tropical America, Bermuda, etc., whence it has been intro- duced into Southern Europe; its fruit imparts a red tinge to the urine of those who eat it. 0. tuna furnishes a rich car- mine pigment, used in Naples as a water- color. O. dillenii is tised in the Deccan as a hedge plant about cantonments. Cochineal insects brought to India flour- ished on it, and it yields a coarse fiber used in paper making. ORACLE, in anthropology, oracles are of high antiquity. They existed among the Egyptians (Herod, v: 89, viii: 82) , and the poetry of the Greeks and the Romans is full of allusion to them. The Hebrews might lawfully, by the high priest, consult the Urira and Thummim (Num. xxvii: 21), but they also illicitly sought responses from teraphim (Judges xvii: 5), and from the gods of surround- ing nations (II Kings i: 2, 3, 6, 16). The responses were supposed to be given by a supernatural afflatus, either through a person, as at Delphi and Cumse, _ or through some object, as in the rustling of the sacred grove at Dodona. But in every case there is present the idea of a power more than human taking posses- sion of a person or thing, and making that person or thing the vehicle of the response. ORAN, a seaport of Algeria, stands on the Gulf of Oran, 261 miles W. by S. of Algiers, and 130 miles S. of Cartagena in Spain. It stretches up the foot of a hill, is defended by detached forts, has a thoroughly French appearance, having been mainly built since 1790, when the old Spanish town was destroyed by an earthquake, and possesses a Roman Cath- olic cathedral (1839), a grand mosque, a large military hospital, a college, a seminary, and two citadels or castles. The harbor is protected on the N. and E. by moles constructed in 1887 at a cost of $1,400,000; alfa, iron ore, and cereals are the chief of the exports. Oran was built by the Moors. During the second half of the 15th century it was a highly prosperous commercial town, and was celebrated for its cloth and arms and fine public buildings. But it was taken by the Spaniards in 1509 and made a penal settlement. It was captured by the Turks in 1708, but retaken by the Span- iards in 1732. In 1790 it was destroyed by an earthquake, and shortly after was altogether abandoned by the Spaniards, the Turks occupying it again in 1792. The French took possession of the town in 1831. Pop. about 125,000. ORANG OUTANG, in zoology, Simia satyrus, the Mias of the Dyaks; also known as the "wild man of the woods." It is a dull, slothful animal, but possessed ORANG OUTANG of great strength. These animals are now confined to the swampy forests of Sumatra and Borneo. Their height has been variously stated, but we have not the least reliable e'idence of the exist- ence of orangs in Borneo more than four feet two inclies high. The legs are very short, the arms are disproportionately long, reaching to the ankle when the ani-
