336 POLAR PROBLEMS 



been of an entirely different order from the few feet or yards per 

 year which is today the rate of advance of the majority. Such a 

 survey is one of the important tasks of the expeditions of the future, 

 which should, incidentally, glean much further valuable information, 

 if only in general terms, about the constitution of the lands from which 

 the debris has been reft. Valuable petrological and paleontological 

 evidence has already been brought to light by the biologist's dredge, 

 notably the nest of iceberg-borne boulders brought up by the dredge 

 of the Scotia, which more than doubled our knowledge of the Archaeo- 

 cyathus limestones of Antarctica and proved their occurrence on 

 the opposite side of the continental divide from where they were 

 first collected by Shackleton's sledge team. Even the contents of 

 the stomachs of sea-living animals cannot be neglected from this 

 point of view, valuable hauls having been obtained from both seals 

 and penguins off portions of the coast line where no exposed rock 

 exists. 



At the same time the glaciologist should use every other possible 

 opportunity for obtaining evidence of the erosive powers of ice. 

 Many further measurements of the speed of different types of glaciers 

 are required, and evidence of signs of former stream erosion should 

 be looked for everywhere. If the great through valleys of the South 

 Victoria Land horst owe their inception and deepening entirely to the 

 abrasive and plucking work of ice, that fact alone should go far to 

 prove the potency of an ice stream as an eroding agent. 



Internal Ice Investigations and the Methods 

 To Be Pursued 



Knowledge of the interior of Antarctica, and therefore of its 

 continental ice, is very scanty indeed. Of all the expeditions that 

 have landed on its shores only five have penetrated more than a 

 couple of hundred miles inland, and all but one of these have been 

 based on the Ross Sea sector of the continent, whence sledge 

 parties have made hasty, almost furtive, journeys across the plateau 

 in midsummer in the attempt to reach their geographical objective, 

 the south, or south magnetic, pole. Nevertheless, we know that 

 practically the whole continent is covered with ice, the surface of 

 most of which lies at a great elevation. Most of the sledge parties 

 concerned have traveled across an ice divide which lies close to the 

 steep coastal range of South Victoria Land. We cannot feel sure 

 that this forms the main ice divide or that the slopes on the other 

 side are for this reason uniformly less steep than in the area traversed, 

 though the evidence as yet to hand suggests that such is the case. 

 The thickness of the continental ice is entirely unknown, though in 

 some places evidence exists that it is underlain for many miles beyond 



