In Ocean Depths 



and unalterable climate. Where changes of cold 

 and heat do come about, they are very uncertain, 

 and usually they are due to other causes than 

 those which bring about the succession of seasons 

 upon Earth. 



Many remarkable facts have lately come to 

 light with respect to Ocean's temperatures. In 

 far northern and far southern regions, near the 

 two poles, the whole sea is very cold. One 

 might expect the converse of this in tropical 

 regions — a whole sea intensely warm. But this 

 we do not find. The shallower parts — those in- 

 cluded in the hundred-fathom limit — may be 

 nearly as warm below as above. When, how- 

 ever, deep-sea soundings are made, when the 

 registering thermometer is despatched on its 

 mission of inquiry miles below the surface, then 

 the report brought up is generally of great cold. 



In almost all deeper parts, the tale is told of 

 a frigid under-layer, — of water nearly and some- 

 times quite down to the freezing-point of fresh 

 water. This, not only in Polar Seas, not only 

 in Temperate Oceans, but in the hottest portions 

 of the Tropics. The Atlantic, near the equator, 

 is icy in its depths. 



A reckoning has been made that, if the floor 

 of the whole ocean, omitting shallower parts, 



47 



