Page:Physical Geography of the Sea and its Meteorology.djvu/44

18 workshops of nature, such mighty tasks, such important offices, such manifold and multitudinous powers have been assigned.

50. The three great oceans.—This volume of water, that out-weighs the atmosphere (§1) about 400 times, is divided into three great oceans, the Atlantic, the Pacific, and the Arctic; for in the rapid survey which in this chapter we are taking of the field before us, the Indian and Pacific oceans may be regarded as one.

51. The Atlantic.—The Atlantic Ocean, with its arms, is supposed to extend from the Arctic to the Antarctic—perhaps from pole to pole; but, measuring from the icy barrier of the north to that of the south, it is about 9000 miles in length, with a mean breadth of 2700 miles. It covers an area of about 25,000,000 square miles. It lies between the Old World and the New: passing beyond the "stormy capes," there is no longer any barrier, but only an imaginary line to separate its waters from that great southern waste in which the tides are cradled.

52. Its tides.—The young tidal wave, rising in the circumpolar seas of the south, rolls thence into the Atlantic, and in 12 hours after passing the parallel of Cape Horn, it is found pouring its flood into the Bay of Fundy.

53. Its depths.—The Atlantic is a deep ocean, and the middle its deepest part, therefore the more favourable (§ 13) to the propagation of this wave.

54. Contrasted with the Pacific.—The Atlantic Ocean contrasts very strikingly with the Pacific. The greatest length of one lies east and west; of the other, north and south. The currents of the Pacific are broad and sluggish, those of the Atlantic swift and contracted. The Mozambique current, as it is called, has been found by navigators in the South Pacific to be upwards of 1600 miles wide—nearly as broad as the Gulf Stream is long. The principal currents in the Atlantic run to and fro between the equator and the Northern Ocean. In the Pacific they run between the equator and the southern seas. In the Atlantic the tides are high, in the Pacific they are low. The Pacific feeds the clouds with vapours, and the clouds feed the Atlantic with rain for its rivers. If the volume of rain which is discharged into the Pacific and on its slopes be represented by 1, that discharged upon the hydrographical basin of the Atlantic into the Atlantic would be represented by 5. The Atlantic is crossed daily by steamers, the Pacific rarely. The Atlantic washes the shores of the most powerful, intelligent, and Christian nations;