OCEAN, the largest of the five great oceans (see OCEAN), lies between Amer ica on the e., and Asia, Malaisia, and Australasia on the west.. The name " Pacific," given to it by Magellan, the first European navigator who traversed its wide expanse, is doubtless very appropriate to certain portions of this ocean; but as a whole, its special claims to the epithet are at the least doubtful, though the name has by long usage become too well established to be easily supplanted by any other.
The greatest length of the Pacific ocean from the Arctic (at Behring's strait) to the Antarctic circles is 9,200 m., and its greatest breadth, along the parallel of lat. 5° n., about 10,300 in. ; while its area may be roughly estimated at 80,000,000 English sq.m., or about two-fifths of the whole surface of the earth. Its form is rhomboidal, with one corner incomplete (at the s.), and its surface is studded with numberless islands, either scattered or in groups; these, however, are chiefly confined to the western side. Along the whole eastern side there is a belt of sea of varying width, which, with a very few exceptions, is wholly free from islands.. The deepest sounding yet found (in n. let. 11' 24% e. long. 143° 16') in the Pacific ocean is 20,830 ft., or above 5 m.---nearly equal to the height of the highest mountain on the globe. .
The coasts of the Pacific ocean present a general resemblance to those of the Atlantic, and the similarity in the outline of the western coasts of each is even striking, espe cially n, of the equator; but the shores of the former, unlike those of the latter, are sinuous, and, excepting the D.C. coast of Asia, little indented with inlets. The shore on the American side is bold and rocky, while that of Asia varies much in character.
Though the Pacific ocean is by far the largest of the five great oceans, being about equal to the other four in extent, the proportion of land drained into it is comparatively insioiiricant. Its basin includes only the narrow strip of the American continent to the of the Andes and Rocky mountains; Melanesia (with the exception of almost the whole of Australia), which contains few rivers. and none of them of large size; the Indo. Chinese states, China proper, with the c. part of Mongolia, and Manchuria in the Asiatic continent.
ll'ind.s.—The trade-winds of the Pacific have certain peculiarities, which have only lately been discovered. In general, they are not found to preserve their peculiar char acteristics except within certain limits, thus, the s.e. trades are found to blow steadily only between 92° and 140° of w. long.; while the n.e. trades are similarly fluctuating, except between long. 115° w. and 214° w. Beyond these limits, their action is in whole or in part neutralized by the monsoons and other periodical winds peculiar to the tropi cal regions of the Pacific. In Polynesia, especially near the New Hebrides group, hurri canes are of frequent occurrence from November to April, but they exhibit few of the terrible characteristics which distinguish the hurricanes of the West Indies and Indian ocean. North and s. of the tropical zone the winds exhibit little periodicity, being found to blow from all parts of the compass at any given season of the year, though a general westerly direction is most frequent among them. On the coast and at cape Born, w. winds prevail during the greater part of the year, while in the sea of Okhotsk they are of rare occurrence. The frightful typhoon (q.v.) is the terror of mariners in
the Chinese seas, and may occur at all seasons of the year. There are many other winds and storms, such as white squalls, cyclones, " tempestades," etc., which are con fined to particular localities, and will be found noticed under other heads, and also under STORMS.
Currents.—The currents of the Pacific ocean, though less marked in character and effects than those of the Atlantic, are yet of sufficient importance to require a brief notice. The Southern Pacific current takes its of Van Diemen's Land, and flows eastward at the rate of half a mile per hour, dividing into two branches about long. 98° w., the northern branch, or current of Mentor, turning northward, and gradually losing itself in the counter equatorial current; the southern branch continuing its eastward course until it is subdivided by the opposition of cape Horn into two branches, one of which, the cold current qf Peru, or Humboldt's current, advances northward along the w. coast of South America, becoming finally absorbed in the equatorial current; the other washing the coast of Brazil, and becoming an Atlantic current. The Pacifi'c ocean, like the Atlantic, also possesses its equatorial current, separated into a northern and southern current by the equatorial counter-current. It sweeps across the whole ocean from e. to west. Two subdivisions of the southern current, called respectively the "cur rent of Rossel" and the "warm current of Australia," flow, the one through the Polyne sian archipelago to New Guinea, and the other along the e. coast of Australia. The northern equatorial current, after reaching the coast of Asia, turns n.e., washing the shores of China and Japan, under the name of the black or Japan current; it then sends off a branch along the coast of Kaintchatka, and advances eastward till it becomes lost on the n.w. coast of North America. There are other minor currents, the most remarkable of which is Pleurien, which describes a kind of irregular circle with a radius of about 240 miles. It is situated in lat 25° to 40' n., and long. to 155° west. All • these currents have their corresponding counter-currents.
There are two "sargassos" or weedy seas of considerable extent in the Pacific ocean. one lying e.s.e. of New Zealand; the other, and by far the larger, about 15° w. of San Francisco in California. There is also a large region lying nearly half-way between cape Horn and New Zealand, which seems to correspond to the dese its on land, as mariners report it almost wholly destitute of any signs of life either in sea or air.
ffistory.—The existence of this ocean first became known to Europeans through Colum bus, who had received accounts of it from some of the nativ,:s of America, though it was first seen by Balboa, Sept. 29, 1513, and first traversed by Magellan 8 years after wards; but its size. limits, and the number and position of its islands, etc., were little known till long afterwards. Capt. Cook deserves the first place among the investiga tors of the Pacific ocean; and after him conic Anson, the two Bougainvilles, La Perouse, Carteret, Vancouver, Kruzenstern, Kotzebue. etc. But the most thoroughly scientific examination of its physical condition is that accomplished by the Challenger expedition of 1873-76.