2 THE OCEAN WORLD. 



3,500 fathoms. It is true that a great number of deep-sea soundings 

 fall short of that limit ; but, on the other hand, many others reach 

 7,000 or 8,000. Admitting that 3,000 fathoms represent the mean 

 depth of the ocean, Sir John Herschel finds that the volume of its 

 waters would exceed 3,279,000,000 cubic yards. 



This vaiit volume of water is divided by geographers into five 

 great oceans : the Arctic, the Atlantic, Indian, Pacific, and Antarctic 

 Oceans. 



The Arctic Ocean extends from the Pole to the Polar Circle ; it 

 is situated between Asia, Europe, and America. 



The Atlantic Ocean commences at the Polar Circle, and reaches 

 Cape Horn. It is situated between America, Europe, and Africa, in 

 length of about 9,000 miles, with a mean breadth of 2,700, covering 

 a surface of about 25,000,000 square miles, placed between the Old 

 World and the New. Beyond the Cape of Storms, as Cape Horn may 

 be truly called, it is only separated by an imaginary line from the vast 

 seas of the south, in which the waves, which are the principal source 

 of tides, have their birth. Here, according to Maury, the young tidal 

 wave, rising in the circumpolar seas of the south, and obedient to the 

 sun and moon, rolls on to the Atlantic, and in twelve hours after passing 

 the parallel of Cape Horn is found pouring its flood into the Bay of 

 Fundy, whence it is projected in great waves across the Atlantic and 

 round the globe, sweeping along its shores and penetrating its gulfs 

 and estuaries, rising and falling in the open sea two or three feet, but 

 along the shore having a range of ten or twelve feet ; sometimes, as 

 at Fundy on the American coast, at Brest on the French coast, and 

 Milford Haven and the mouth of the Severn in the Bristol Channel, 

 rising and falling thirty or forty feet, " impetuously rushing against 

 the shores, but gently stopping at a given line, and flowing back to 

 its place when the word goes forth, ' Thus far shalt thou go and no 

 farther.' That which no human power could repel returns at its 

 appointed time so regularly and surely, that the hour of its approach 

 and the measure of its mass may be predicted with unerring certainty 

 centuries beforehand." 



The Indian Ocean is bounded on the north by Asia, on the west 

 by Africa, on the east by the peninsula of Molucca, the Sunda Isles, 

 and Australia. 



The Pacific, or Great Ocean, stretches from north to south, trom 

 the Arctic to the Antarctic Circle ; being bounded on one side by 

 Asia, the island of Sunda, and Australia, on the other by the west 

 coast of America. This ocean contrasts in a striking manner with 

 the Atlantic : the one has its greatest length from north to south, the 



