50 GLACIOLOGY 



This sketch shows in the foreground on the left Cape Irizar, which at the point 

 where the sketch was made is 600 feet above sea-level. The granite surface of this 

 cape is strewn with erratics of intensely glaciated small pebbles of diabase, gabbros, 

 hornblende-lamprophyres, sphene-granites and pink felsites, &c. The rock sur- 

 face not only exhibits numerous roches mountonnees, but is powerfully grooved in 

 a general W.N.W. and E.S.E. direction. This is a point of special interest, as a 

 glance at the map will show at once that this is the trend of the David Glacier, 

 the principal feeder of the Drygalski Ice Barrier. It is obvious that this intense 

 glaciation of the summit of Irizar is due to an ancestor of the above glacier, at a 

 time when it was confluent with the Davis Glacier. There must have been a con- 

 siderable thickness of ice over the top of Cape Irizar to have produced this intense 

 glaciation. At this time the David Glacier before reaching the coast must have 

 been at least 20 miles in width instead of from 6 to 7 miles as at present. The 

 contour of the hills grouped around Mount Neumayer is clearly indicative that they 

 have been heavily glaciated close up to, if not right over, their summits. If this 

 inference is correct — and there seems little reason to doubt it — the David Glacier at 

 its jjresent outlet near Cape Philipjsi * was formerly at least 2000 feet higher than 

 at present. 



On the north side of Geikie Inlet, and on the north side of the Drygalski 

 Glacier, is a magnificent glacier-cut cliff, approximately 8 to 10 miles in length and 

 some 1000 feet or so in height. It ends eastwards in Cape Philippi. At the back 

 of this magnificent wall is the Mount Neumayer, Bellinghausen, and Priestley 

 Massif To the right, on the far side of the Drygalski Ice Barrier, rises the massif 

 of Larsen and Gerlache, with the Larsen Glacier between. Dimly seen through the 

 clouds on the day the sketch was made, behind Larsen is Mount Nansen, 70 miles 

 distant, and still farther to the right is probably Mount Melbourne, 90 miles distant. 

 It will be noticed that the surface of the Drygalski Ice Barrier is bristling with 

 hummocks, ridges, and occasional seracs. 



On approaching the glacier from the south side we found that the sea ice by 

 degrees developed a more and more undulating surface. We heard the roar of a 

 crack opening in the ice near by, and as it was at the time a calm day, this cracking 

 was probably due to the pressure of the ice of the active Drygalski Barrier.f There 

 were here two sets of sastrugi, one directed N. and S., the true blizzard sastrugi, 

 the other directed about E. 35° S. and W. 35° N., produced by wind coming from 

 that direction fi'om off the plateau. The latter sastrugi are made by the land 

 breezes or plateau wind, the great " consequent " air stream which blows from off' 

 the cold plateau at night on to the relatively warmer surface of Ross Sea. This 



* Named after the distinguished geologist, the late Dr. Philippi, the associate of Drygalski 

 on the Gauss- Antarctic Expedition. 



t Some of these cracks, newly opened in the sea ice by the forward pressure of the Drygalski 

 Glacier Ice, were about 10 feet in width. 



