L] GEOLOGICAL OBSERVATIONS 345 



land and which have no obvious single source may be described 

 as 'piedmonts.' 



(a) Three types may be distinguished, and the first may be 

 termed a piedmont on land. The slope of snow west of the 

 stranded moraines in McMurdo Bay should probably be included 

 here, but as there is evidence that it is a relic of a once greater 

 glaciation, it has been included with the more permanent develop- 

 ments of ' shore-ice.' Along the foot of the Prince Albert Range 

 there appear to be many such snow-slopes, and together they 

 produce a continuous series of piedmonts which coalesce almost 

 imperceptibly with the great ice-streams flowing between the 

 hills. 



(b) The second type of piedmont is well represented on the 

 sides of Coulman Island. The flat top of this island sheds its 

 superfluous snow over the bare rock-cliffs, and produces along 

 the base of the cliffs great snow-talus fans. These fans, which 

 are sometimes separate, sometimes continuous, end as a cliff of 

 ice in the sea. The outline of this cliff is an undulating line, and 

 the height usually varies between fifty and 100 feet. This type 

 may be called a ' piedmont aground,' because the ice is resting on 

 the sea-bottom, and the bergs seem to be calved just at that point 

 where the ice becomes water-borne. 



(c) Piedmonts afloat are by far the most important and are 

 represented by three very prominent examples — namely, the sheet 

 of ice in Lady Newnes Bay, the sheet near Cape Gauss, and the 

 great Ross Ice Sheet. All three have, as characteristics, a surface 

 of great extent which may or may not be slightly undulating, a 

 seaward edge forming a cliff between fifty and 200 feet high, and 

 a depth of water at that edge which is without a doubt sufficient to 

 float the ice. (As far as possible I have avoided using the word 

 ' barrier,' as it does not imply area, and in preference employ the 

 term ' sheet ' in restricted sense, as it does imply a plane super- 

 ficies.) In this summary it is not necessary to marshal the 

 evidence in favour of the view that these ice-sheets are afloat, and 

 we will therefore conclude with the suggestion that the term 

 ' piedmont afloat ' is descriptive of this class of ice formation. 

 No foreign matter was observed in the great ice-cliffs of these 

 piedmonts, and no rock debris was met with on its surface either 

 by Mr. Royds and Mr. Bernacchi on their journey south-eastwards, 

 or by Captain Scott and his party on the great journey southwards. 

 Soundings made in an area which was covered by ice only sixty- 



