46 GLACIOLOGY 



As Mr. Griffith Taylor, Senior Geologist to the late Captain R. F. Scott's 

 Expedition, has made recently a special study of the Antarctic cirques, we omit 

 more than passing reference to them in this Memoir. Icebergs will be described 

 under sea ice, in which we include all fragments of floating ice, as well as fast ice. 



We may now pass on to consider the glaciers of the Antarctic Horst in detail, 

 commencing with the northernmost group examined by us, the Drygalski-Reeves 

 Piedmont.* 



Reference to the map (Plate IX.) shows that each of these three glaciers is of 

 the "outlet glacier" type, that is, they ai'e ice canals draining vast inland ice-fields, 

 and resemble the glaciers of the west coast of Greenland. The ice in excess of 

 that which is held by frictional resistance moves under gravity and other causes 

 through the channels of the Reeves, the Larsen, and Drygalski and other glaciers 

 into Ross Sea. These glaciers preserve their individuality only where they cross 

 the great horst. To its west they are united in the vast inland snow-fields and 

 underlying ice-fields, while on the coast to the east the Larsen Glacier is united 

 in the form of an " ice-apron," or piedmont afloat, to the Drygalski Tongue, which 

 passes inland into the David Glacier. The united Drygalski and Larsen ice-aprons 

 almost coalesce on the north side of the Larsen Piedmont with that of the 

 Reeves Glacier. Formerly during the period of maximum glaciation all three 

 must have not only been united together, but were also joined along the coast 

 to the Davis Glacier, the Cheetham Ice Tongue, the Harbord Ice Tongue, the 

 Mawson Glacier with the Cotton Glacier, the Nordenskjold Tongue, the Fry 

 Glacier, the Penck Glacier, the Mackay Glacier, and the Ferrar Glacier. As the 

 last mentioned glacier was formerly united to the ice of the great Ice Barrier 

 — it was probably so united in Sir James C. Ross' time in 1840-42 — we may 

 conclude that that gigantic piedmont afloat was formerly continuous to at least 

 as far north as Evans Coves, if not to the north side of Terra Nova Bay near 

 Cape Washington. 



All trace of the great continuous piedmont ceases just before Cape Washington 

 is reached. The high steep-to character of the coast at Cape Washington, with 

 absence of the usual coast platform, is shown in Figs. 1 and 2 of the Physiographic 

 Chapter. Thei'e can be little doubt that, during the maximum glaciation, the whole 

 coast and south-west part of Ross Sea, from Cape Bird on the south to Cape 

 Washington on the north, was filled with ice. This would give the Ross Barrier 

 an extension of about 220 miles northwards of its present northerly limit, so 

 that during the maximum glaciation the Ross Barrier had a total length of perhaps 

 700 miles. 



In some sense then, in dealing with the Reeves, Larsen, and David Glaciers, 

 we are dealing with the now shrunken former tributaries of the Ross Barrier. By 



* 



The following desciiptious of the glaciers of this region are based on the observations of the 

 Magnetic Pole Party — Professor David, Mawson, and Mackay. 



