THE HEART OF THE ANTARCTIC 



in the form of englacial or subglacial streams. These 

 in some cases cut deep open valleys with more or less 

 precipitous sides; in other cases they tunnel channels for 

 themselves under the covering of hard snow and ice, and 

 the roofs of these tunnels collapsing through want of 

 support produce rugged ravines, very difficult to cross 

 with sledges. 



This Drygalski Ice Barrier, on its northern side, con- 

 tained in places a considerable amount of moraine material. 

 It was evident that at the time when the glaciation of 

 this region was at its maximum it must have been con- 

 tinuous with the Mount Nansen glacier. These two 

 glaciers, when united, doubtless formed a huge piedmont- 

 afloat. 



(3) Barrier Snow- and Ice-fields. — The structure 

 of the Nordenskjold and Drygalski Barriers throws con- 

 siderable light on one of the most difficult problems of the 

 Antarctic — the origin of the Great Ice Barrier. To 

 ascertain the amount of annual snowfall on this Great 

 Barrier is of very great importance, but we found this a 

 hard problem, chiefly on account of the difficulty of dis- 

 tinguishing between true newly fallen snow and old snow 

 which has been drifted along by blizzards. We tried, 

 during our observations in Antarctica, to eliminate the 

 drift snow from the true snowfall, and our general con- 

 clusion now is, that at Cape Royds the annual snowfall is 

 equal to about in. of rain. On the journey of the 

 southern depot party under Joyce, when laying a 

 depot for the relief of the returning Southern Party in 

 January 1909, the fortunate discovery was made of Cap- 

 tain Scott's old Depot A. The sharp eyes of Day 

 discerned, at a distance of several miles, the top of the 

 depot bamboo pole with just a wisp of the old black flag 

 still attached to it. Knowing the importance, from a 

 scientific point of view of estimating the extent and direc- 



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