346 THE VOYAGE OF THE 'DISCOVERY' [Arpx. 



five years ago, proved the sea-floor to be mainly rock-floor with 

 occasional pebbles and diatoms, which show that the soles of 

 these floating sheets do carry rock matter. 



The Glaciers 



All Heim's types of glaciers may be recognised in South 

 Victoria Land. 



(a) The ice-streams, or the Greenland type of glacier, which 

 have their source in the inland ice, end in the sea ; these are 

 present in great number in the Prince Albert Mountains, as well 

 as in the succession of ranges forming the coast between latitudes 

 79° and 83 S. They also appear to be developed in the Admiralty 

 Range, and there are two examples — the Ferrar Glacier and the 

 Koettlitz Glacier — which lie north and south respectively of the 

 Royal Society Range. 



{b) The Norwegian type of glacier consists of streams of ice 

 flowing down well-refined valleys from a large firn field. This 

 is exemplified by the Blue Glacier, which arises in the Royal 

 Society Range and ends in McMurdo Sound in a cliff* some 

 seventy or eighty feet high. 



(r) Valley glaciers, or those of Alpine type occur in great pro- 

 fusion in the Royal Society Range. Some of those flow into the 

 Ferrar Glacier and blend with it, while others, such as the three 

 flowing southwards into the North Fork, end some distance above 

 the ice in the main valley. 



{d) Cliff-glaciers are best represented on the left bank of the 

 East Fork of the Ferrar Glacier, but others may be seen along the 

 coast of South Victoria Land, notably on Cape Washington. The 

 cliff-glaciers among the Royal Society Mountains often arise in 

 corries and are often only an intermediate stage between a ' corrie " 

 and a ' valley ' glacier. 



(e) The corrie-glaciers that are found at the foot of the Inland 

 Forts are perhaps the most notable. Four occur here, and they 

 fill up the cirques between the Forts. At present they flow south- 

 wards and are building up crescentic moraines around their 

 terminal faces ; whereas, at some former time, they drained 

 northwards through cols into another valley system. 



(/) Ice-slabs occur among the foothills of the Royal Society 

 Range, and consist of masses of ice about fifty feet thick, and four 

 to six square miles in area. They appear to have been nourished 



