E.— GEOGRAPHY. 79 



In any case, it looks probable that our knowledge of Antarctica con- 

 firms the growing belief that the Pacific basin is girdled by a ring of fold 

 mountains marking the course of a system of geosynclines. The remains 

 of the borderlands of this Pacific geosyncline may possibly be found in 

 small islands in that mysterious ice-bound region to the north of Edward 

 Land which no ship has been able to penetrate. 



In the face of these great problems in exploration, it seems trivial to 

 speak of the minor ones that await solution in the south. Reference, 

 however, may be made to the desirability of measuring an arc of meridian 

 in a high southern altitude. F. Debenham has pointed out how Victoria 

 Land lends itself to this task. 1 I have not time to dwell on the problems 

 of meteorological exploration and can only point out that much has yet 

 to be done in explaining the peculiar Antarctic blizzards which rank 

 among the fiercest winds on the face of the globe. G. C. Simpson has 

 given an explanation of these in the Ross Sea, but are the blizzards of 

 Wilkes and Coats Lands, which occur under different topographical 

 conditions, amenable to the same explanation, or has W. H. Hobbs 

 found the solution in his theory of strophic winds associated with glacial 

 anticyclones, a theory which he applies also to Greenland where he is at 

 present investigating it ? 



Recent observations in North-East Land, Spitsbergen, confirm the 

 association of this general air circulation with a dome of ice-covered land, 

 but, as Sir Napier Shaw, L. C. W. Bonacina and others have pointed out, 

 we require another term than anticyclone for this state of affairs since 

 the high pressure is only a shallow surface effect resulting from local 

 conditions, and not a true anticyclone developed as the outcome of general 

 atmospheric circulation independent of local topography. Even the 

 qualification of ' glacial ' does not remove a possible confusion of ideas. 

 The supply of cold air from polar regions towards lower latitudes appears 

 to be independent of pressure inasmuch as the winds are katabatic winds 

 flowing down the slope of high land. It is orographical relief and not 

 pressure which supplies the driving force of the cold air currents of the 

 polar front. 2 



A further important meteorological problem, with strong geographical 

 bearings, is the alimentation of the ice-sheet. We know that it is wasting 

 by the calving of icebergs, by surface ablation, and other processes, and 

 that it has shrunk considerably since its Pleistocene maximum, but we are 

 at a loss to explain satisfactorily how the precipitation in the heart of an 

 anticyclone can ever have been sufficient to allow such an ice-sheet to 

 grow. There is every reason to believe that during the great Ice Age 

 ice-sheets did not develop over the Arctic islands of Canada or over 

 most of Siberia. The temperatures were low, but moisture was in- 

 sufficient. And yet in the Southern Hemisphere the ice grew in the heart 

 of a vast high-pressure area. 



1 British Antarctic Expedition, 1910-13. Report on Maps and Survey, 1923. 



3 W. H. Hobbs, The Glacial Anticyclones (1926). A valuable symposium on Arctic 

 meteorology is the collection of papers read at the first meeting of the International 

 Society for the Exploration of Arctic regions by Airship, published in Petermann's 

 Mitteilungen, Erganzungsheft 191 (1927). A chart shows the route of the proposed 

 expedition and the location of observing stations. 



