24 Depth of the Ocean. 



Oceans. With regard to the general distribution of depth in 

 the Southern Ocean, its bottom appears to rise gradually from 

 nearly 3000 fathoms at the fortieth parallel (with the exception 

 of the intervening plateaux) to little over 1500 fathoms at the 

 Antarctic circle. There are also indications of an area of 

 depression, of an average depth of 2000 fathoms, making the 

 circuit of the globe between the parallels of 50 and 6o° lat. S. 

 The whole surface of the Southern Ocean is strewn with masses 

 of floating ice, some of them forming islands many miles in 

 extent, and rising from 100 to 300 feet above the level of the 

 sea — an imposing spectacle, but fraught with much danger to the 

 navigator in these regions. It is this central ocean which 

 supplies the masses of cold water that fill up nearly two- 

 thirds of the total depth of the Atlantic, Pacific, and Indian 

 Oceans. 



The Basin of the Antarctic Sea. — We are indebted to Sir 

 James Ross for the only soundings procured within the Antarctic 

 circle. They are situated in the wide inlet, discovered by that 

 illustrious navigator in the year 1840, which extends along the 

 meridian of New Zealand, and terminates at the foot of Mount 

 Erebus and Mount Terror. These soundings, which are all 

 under 500 fathoms, viewed in combination with the above- 

 mentioned gradual rise of the bottom of the Southern Ocean 

 towards the Antarctic Circle, justify the assumption that the seas 

 included within the latter do not exceed 1500 fathoms in depth, 

 their average depth probably falling below this estimate. The 

 extensive formation of ice in this region, as well as the numerous 

 indications of land reported by the daring sailors who have 

 penetrated so far south, suggest the hypothesis of the existence, 

 if not of an Antarctic continent, at all events of a considerable 

 extent of land, rising in the mountain ranges and volcanoes of 

 Victoria Land to 10,000 and 15,000 feet above the level of 

 the sea. 



