140 SEA AND LAND 



inlkicnce of the vast amount of ice froni the Antarctic Sea 

 which floats near to its shores. Though not of great impor- 

 tance in terrestrial conditions, icebergs must be reckoned as 

 a factor with which the meteorologists of the future will have 

 to deal. In forecasting the weather conditions not only of 

 the seas where they occur, l)ut also of the neighboring lands, 

 it will be necessary to take account of the migrations of these 

 wanderers froni the polar region, and to estimate their effects 

 upon the heat and moisture of those districts. 



To the student of the geological processes which are now 

 going on upon the earth, icebergs, and ice-lloes as well, will 

 afford most interesting subjects of inquiry. Not only do they 

 affect the temperatures of the sea and land, and thus indirectly 

 influence the conditions of the life they bear, but they exert 

 certain curious direct effects upon the distribution of organic 

 species and in the carriage of sediments. We will first note 

 the action of these floating ice-fields in carrying animals from 

 one region to another. It is the habit of the animals of high 

 latitudes, particularly the polar bears, to seek the margin of 

 the sea for the food they may obtain from its waters. The 

 bears indeed win in winter their entire subsistence from this 

 source of supph' ; even in summer they obtain little else than 

 what the ocean affords them. Prow^ling along the shore and 

 swimming far in its waters, with occasional rests on. the float- 

 ing ice-islands, it frequently happens that they are borne away 

 to sea on these rafts. In most cases these creatures starve to 

 death or are drowned wht?n their supports melt away ; but it 

 sometimes happens that the wandering ice conveys them to 

 some other land, (irounding in the shallow water next the 

 shore, the animals, if not too much exhausted, may win the 

 shore and proceed to multipl\- in their new-found home. 



