OEIOLE 46 OBKNEY ISLANDS and the Caroni. About 120 miles from the Atlantic, into which it rolls its milk- white flood, its delta (8,500 square miles) begins. Of the numerous mouths which reach the ocean over 165 miles of coast line only seven are navigable. The waterway principally used by ocean- going vessels, which penetrate up to Ciu- dad Bolivar (Angostura), a distance of 245 miles, is the Boca de Navios, vary- ing in width from 3% to 23 miles. The total length of the river is some 1,550 miles, of which 900, up to the cataracts of Atures, are navigable, besides a far- ther stretch of 500 miles above the cata- racts of Maypures; area of drainage basin, 368,600 square miles. OBIOLE, Oriolus galbula, the type- species of the family Oriolidse. Its con- spicuous plumage, bright yellow con- trasted with black, chiefly on wings and tail, often brings about its death. The nest is suspended under the horizontal EUROPEAN ORIOLE fork of a bough; the eggs are of a shin- ing white, sometimes tinged with pink, and sparsely dotted with purple. It is well known in Europe. Its range in summer is as far E. as Irkutsk, in win- ter it is found in Natal and Damara- land. In India it is replaced by Oriolus kundoo. ORION, in mythology, a celebrated Greek giant and hero, and the reputed son of Hyrieus of Hyria, in Bceotia. So immense was his size, that when he wad- ed through the deepest seas he was still a head and shoulders above the water; and when he walked on dry land, his stature reached the clouds. After his death he was placed with his hound in heaven, where, to this day, the following constellation bears his name. In astronomy, one of the ancient con- stellations found by Ptolemy. The equi- noctial passes nearly through its center, and it is situated in the Southern Hemi- sphere with respect to the equator. Four of the seven stars constituting the constellation are situated in the middle of it, in a straight line. Two of these are of the first magnitude, namely Betel- guese or Beltegeux, in the right shoul- der, and Rigel in the left foot. In the middle of the square are three stars of the second magnitude, which form what is called the belt of Orion. The constel- lations which surround Orion are Eri- damus, Canis Major, Gemini, Auriga, and Taurus. Near the sword-scabbard is a remarkable nebula, and within the constellation are thousands of small stars, which are only visible by power- ful telescopes. OmSSA, a maritime province, of Hin- dustan; on the Bay of Bengal; consti- tuted by the British in 1912 out of the state of Bengal, area, 13,743 square miles, pop. about 5,210,000 and the native states of Bihur and Orissa, area, 28,648 miles. Pop. about 5,200,000. The sur- face along the shore is in general low and sandy, and in the interior wild and rugged. The inhabitants are composed chiefly of Oorias, the conquerors of the country, and of wild hill tribes. The largest river is the Mahanadi. The chief towns are Cattack, Puri or Jug- gernauth, and Balasore. ORIZABA, city of the Mexican state of Vera Cruz; 82 miles W. S. W. of Vera Cruz city, and 181 E. S. E. of Mex- ico; in a fertile garden country, 4,030 feet above the sea; contains an extensive cotton factory, paper and corn mills, and railway shops. The volcano of Orizaba, 25 miles N., is a noble pyramid rising to an elevation of 17,876 feet, or, accord- ing to Heilprin's measurements, 18,205 feet. Its last severe eruption was in 1566. Pop. about 40,000. ORKNEY ISLANDS, a growp of 90 Scotch islands, islets, and skerries, of which only 28 are inhabited, and which have an aggregate area of 376 square miles, the largest being Pomona or Main- land (207 square miles), Hoy (53), San- day (26), Westray, South Ronaldshay, Rousay, Stronsay, Eday, Shapinshay, Burray, Flotta, etc. They extend 50 miles N. E., and are separated from Caithness by the Pentland Firth, 6% miles wide at the narrowest. With the exception of Hoy, which has fine cliffs, and in the Ward Hill attains 1,564 feet, the scenery is generally tame, the sur- face low and treeless, with many fresh