GEOLOGICAL OBSERVATIONS 



the berg, this portion of it being formed purely of 

 compressed snow. 



From this fact we were led to speculate as to whether 

 the whole of the berg might not be formed of hard snow, 

 its submerged portion saturated, but only superficially, 

 with sea water. That this was actually the case was proved 

 later by Captain F. P. Evans. He saw in these bergs 

 an excellent shelter for his ship from the blizzards, and 

 moored the Nimrod to one of the larger bergs. While 

 here he took soundings around the most typical of these 

 tabular bergs, and found that whereas its cliff face rose 

 to a height of 80 ft. above sea-level, the berg was aground 

 in only thirteen fathoms of water; that is, the berg was 

 submerged to a depth of 78 ft., so that practically half 

 of it was out of the water and half immersed. This direct 

 observation is obviously of great importance as bearing 

 on the mode of origin and structure of the so-called ice- 

 bergs of the Antarctic. There can, we think, now be little 

 doubt that a great proportion, in some cases the whole, 

 of the material of typical Amtarctic bergs is formed of 

 consolidated snow rather than ice. These observations 

 may now be considered in their bearing on the origin of 

 the Great Ice Barrier. Captain Scott has shown that 

 the Great Ice Barrier for the greater part of its length, 

 probably for 400 miles at least along its edge, is afloat. 

 Wherever we got near to the cKfF face of the Barrier, 

 and we were at times very close to it, we were unable to 

 see anything of the nature of true glacier ice, even in 

 cases where the cliff rose to a height of over 150 ft. above 

 sea-level. On the other hand, there was every appearance 

 of the Barrier being formed of numbers of superimposed 

 layers of snow. On the line of argument previously given 

 it is not improbable that a thickness of 900 ft. of snow, 

 or thereabouts, may accumulate on a large proportion of 

 the Barrier near its terminal cliff, so that obviously, a 



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