340 POLAR PROBLEMS 



all takes place on the under side of the thicker drifts; equally is it 

 true that temperature changes must be practically damped out 

 throughout even the short Antarctic summer at the bottom of any 

 deep crevasse. Certainly there can be no oscillation of the tempera- 

 ture about the freezing point of water such as is postulated to account 

 for bergschrund action in milder climates. No expedition has yet 

 had means or leisure to inquire into these things carefully enough. 

 All energies have been directed towards the more generalized peri- 

 patetic investigations of the pioneer. Here, however, is work and to 

 spare for the trained glaciologists of the more leisured parties of the 

 future. 



Sea Ice: The Antarctic Pack-Ice Belt 



If we turn our attention to sea ice, we find at once that the Antarc- 

 tic pack has attracted far less attention than its rival in the north. 

 The broad features of the meteorology of the southern hemisphere, 

 with its more symmetrical disposition of land and sea, have combined 

 with the earlier and greater development of civilization in the north 

 to make this true. The ice driven north from the shores of the Ant- 

 arctic Continent by southeasterly gales is closely packed between 

 those winds and the northwesterlies of the middle latitudes. There 

 it hangs sullenly as a barrier to southern navigation, but normally 

 well south of the main traffic routes between the ports of southern 

 civilizations. Only occasionally, driven by deep-water currents, do 

 the mighty southern icebergs force their way irresistibly through the 

 sea ice perhaps to strand and form a nine days' wonder — sometimes 

 a source of unexpected income — on southward-reaching temperate 

 shores. Normally the Antarctic pack is out of sight of the seafarer 

 in these days of steam, and out of sight is usually out of mind. Not 

 until the twentieth century have the fresh incursions of the whalers 

 into ice-laden seas in search of finback whales reminded the northern 

 peoples of the existence of the southern sea-ice belt. Nevertheless, 

 its study is of interest, and in this respect much has already been 

 achieved. We know, for instance, of its westerly drift, of certain 

 weak places in the belt which are easily penetrated, and of others 

 where danger is likely to be encountered even in normal years. From 

 the observation of past expeditions it has become clear that access 

 to the thousands of miles of coast yet unexplored is most likely to 

 be achieved along the western shores of northward-reaching land 

 promontories or ice tongues. Conversely, the danger of approaching 

 the coast on the eastward side of such prominences has been upheld 

 in theory and demonstrated in practice more than once. The fact 

 remains that large stretches of the coast line have remained inac- 

 cessible to man even when armed with the combined resources of 

 steam and sail. 



