Page:The New International Encyclopædia 1st ed. v. 14.djvu/854

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OCEAN CUBKENTS. 726 OCEANIC DEPOSITS. of the African ami the Central American coasts; those on the polar side becoming merged in the general easterly drift of higher latitudes. The immense mass of water carried b.v the equatorial drifts in the great oceans causes an ac- cumulation upon the eastern continental shores and a consequent disturbance of equilibrium, which is in each case partially adjusted by a sirtum current, or current due to gravity alone, which in every case follows the shore line and is directed away from the equator. In the Xorth Atlantic Ocean this current is known as the Gulf Stream ; in the South Atlantic as the Bra- zilian Current; in the North Pacific as the Kuro Sivo; in the South Pacific as the Australian Current ; in the Indian Ucean as the Mozambique Current. These are more constant in direction and force than the ordinary drift currents, but likewise are subject to stoppage or even to re- versal. Upon attaining middle latitudes the combined ctfect of the deflective force of the earth's diurnal rotation and of the prevailing westerly winds serves to turn them off shore, and their identity is henceforth lost in the gen- eral easterly drift of the temperate zone. The easterly drift of extra-tropical latitudes exhibits none of the persistency of the westerly drift of the tropical, the currents reported being a])par- eiitly quite as variable as the winds themselves. In the case of the Xorth Atlantic Ocean, the easterly drift divides to the northwestwanl of the Azores, one portion carrying to the southward along the Peninsular ami African shores.' and finally reuniting with the nortli ecjuatorial cur- rent, the whole system forming a vast gentle eddy in close agreement with the prevailing winds ; the remaining ))ortion carries eastward and northward tcjward the shores of Great Britain, Scandinavia, and Iceland. Analog;^ would sug- gest a like division in the case of each of the other oceans, with the possible exception of the North Pacific. The information as to these oceans thus far acciuiuilated is. however, not suf- ficient to establish the hypothesis. Vertical Circti.atio.n. The theory of a ver- tical oceanic circulation rests almost entirely npon the .study of the thermal conditions existing in the Atlantic. The main facts in support of the theory may be siunmarized as follows: (1) The bottom water of every ocean in free com- munication with the pole has a temperature b>it little dift'erent from that in polar latitudes: (2) this is true even in the equatorial regions, where the entire mass of the ocean, in case an influx of cold water did not exist, would by virtue of the insolation attain in the course of time a temperature not lower than 1° F. ; (.31 the bot- tom tfmperatures in the case of those oceans to which the cold polar water has free access are somewhat lower than the bottom temperatures where this communication is restricted: (4) the thickness of this bottom stratum of cold water (tiOO fathoms) is too great to admit of the ex- planation that it is the return flow of the warm water carried poleward by the drift surface cur- rents; (5) there is a continual ascent of glacial water under the line, shown by the moderation of the surface temperatures alonsr the equator. and also by the fact that polar temperatures are here attained at less depth than in s<pmewhat higher latitudes; (fi) on the basis of this hypo- thesis the presence of the cold band along the eastern coast of North America can be explained as the ascent toward the surface of the polar water, diverted from its original ecjuatorial course by the eflect of the earth's rotation, and forced up the Atlantic slojie. BiBUOGRAi'iiY. Croll, Uii the Plu/sical Cause of Ocean C'urrenis (London, 1874) ; Ferrell, The ilotion of Fluids and Solids on the P2arth's .'sur- face," in United States Siynal Serricc Profes- sional Papcrst, Xo. 8 (Washington, 1882) ; Hofl- niann, Zur Mechanik der Meeraistromungeii (Berlin, 1884); Engelhardt, Vnterstichungeti iiher die Struniunfien der Ostnee (Altona, ISOO) ; Page, "Ocean Currents." in Xntional fleoijraphic Mugiizinc (Washington, 1902). See Atl. - Tic Ocean; Pacific Oceax; Ixdian Ocean; Gulf Stream, etc. OCEAN GRO'V^E. A summer resort in Mon- mouth County. X. J.. 29 miles (51 by rail) south of New York City; on the Pennsylvania and the Central of New Jersey railroads (Map: New .Jersey, E 3). Situated directly on the Atlantic Ocean, south of Asbury Park, from which it is separated by Wesley I^ake. Ocean Grove is on the splendid beach for which water- ing places of the New Jersey coast are noted. It is characterized, moreover, by rigid moral and religious observances due to its management by a church organization. Tl;c town, inclosed mostly by natural boundaries, is controlled by a camp meeting association of the Methodist Episcopal Cliurch, founded in 18(59, whose regulations enforce a strict respect for the Sabbath, and prohibit theatrical performances and the sale of intoxicants and toliacco. There are three large public buildings: the Auditorium, post office, and school. In the Auditorium, which seats 10.000 persons, religious meetings are frequently held. Th€ Neptime Township high school was erected at a cost of .^Ti.OOO. The water-works and elec- tric light plant arc ownied and operate<l by the association. The number of summer visitors is estimated at over 2.5.000. though the permanent pojuilatinn is only about 2775. OCEANICA, osh^-Sn'I-ka. or OCEANIA. An ill-defined term used by some geographers to designate all the islands situated in the Pacific Ocean. Others include under that name also the East Indian Archipelago. The best usage seems to confine the name to the small islands lying between Australasia on the west and the Amer- ican continent on the east. These islands fall ethnologically. and to a certain extent geo- gra]ihically. into three nniin divisions: Melanesia (q.v.), in the southwest, nearest to the Austra- lian continent: Micronesia (q.v.), in the north- w<-st ; and Polynesia (q.v.), the largest in extent, including all the islands east of the former two. Consult: Gill. The South Pacific and .Vcic Guinea Past and Present (Sydney. 1892) : Baessler, -YcHp Siidsee-Iiilder (Berlin. 1900) : Schanz, Aus- iralien und die Siid.wc an drr Jahrhundertwende. Koloninlstndi, ,1 ( Herlin. 1901). OCEANIC DEPOSITS. The materials form- ing the floor of the ocean may be classed as terrig- enous deposits, which have been derived from the waste of the adjacent land, and as ])elagic or abysmal aceunnihitions, which are found in the open ocean iH'yond the inlUience of the land. The terrigenous deposits, comprising gravel, sand, and clay, are limited in their distribtition to the continental shores, seldom occurring at a dis- tance of more than 200 miles from the land. As