358 DISCOVERY REPORTS 



In shape and dimensions the individuals of this great congregation showed con- 

 siderable variation. Although all vi^ere of barrier origin and the larger of them retained 

 their typical barrier form, a great many, perhaps the majority, were relatively small and 

 irregularly angular, and were evidently the result of the breaking down of larger slabs of 

 barrier ice such as appear in the background of Plate XIII, fig. 2. There were others that 

 to all appearances had been stranded for a long time, upon which the sea had wrought 

 to such purpose that they had become polished and rounded and had lost all semblance 

 of their original tabular form. In size and height none was remarkable. In length they 

 ranged from about 300 feet or less to i^ miles, the smaller predominating, and while the 

 average height above water of the large regular slabs was perhaps 80 or 100 feet, that of 

 most of the smaller and more irregular pieces was very much less. The highest measured 

 was 285 feet, but this was an exceptional one that had broken down and become ab- 

 normally buoyant. 



No exceptionally unusual forms were noted, though D'Urville, who also encountered 

 enormous numbers of icebergs at the South Orkneys in January and February 1838, 

 records some that were "vraiment merveilleux par leur forme et leur etendue". He 

 describes in particular one that resembled "un immense clocher de 76 metres de 

 hauteur" and another "une vaste citadelle arrondie", which on closer inspection, was 

 seen to have its interior hollowed out like an amphitheatre recalling that of the Colosseum 

 at Rome.^ Apart from those that were worn and polished by the sea there was only one 

 berg that particularly claimed our attention, a tabular one with a large circular hole clean 

 through it some distance above the water-line. No doubt there were others of equally 

 arresting form, but irregular bergs of every shape and size were so numerous during 

 our visit that we were inclined to pay less attention to them than we might otherwise 

 have done. 



Within a mile or two of the southern shores the majority appeared to be aground. 

 From the John Peaks at the southern end of Powell Island we marked how the smaller 

 had stranded themselves close inshore, the larger farther out to sea. In the great con- 

 course that was stranded about the southern entrance to Washington Strait (Plate XIII, 

 fig. 2) a well-marked increase in size to seaward may be noted. Although the majority 

 of the inshore bergs were thus aground, a few that were apparently of considerable 

 draught were nevertheless observed to be afloat where to all appearances the water 

 was too shallow to accommodate them without their coming in contact with the 

 bottom. On January 12, the ' Discovery II ' being at anchor in Ellefsen Harbour, several 

 bergs from 80 to 150 feet in height were observed to be moving slowly northward 

 through Lewthwaite Strait at a point where it is only from 50 to 70 fathoms in depth. 

 A similar phenomenon was observed off the south coast of Coronation Island, where 

 large bergs 150 feet in height were definitely seen to be afloat in from 70-80 fathoms. 

 In view of this evidence it would appear that the bergs in question were of an ab- 

 normally shallow draught, and that certain Antarctic bergs of barrier origin must float 

 with no more and sometimes even less than three-quarters of their bulk submerged. 



1 D'Urville, D., 1842, loc. cit., pp. 65-6. 



