316 CLIMATIC CONDITIONS OF THE GLACIAL EPOCH. 



after Sir Edward Parry Whether ' Parry Mountains ' again take an 



easterly trending, and form the base to which this extraordinary mass of ice 

 is attached, must be left for future navigators to determine. If there be 

 land to the southward, it must be very remote, or of much less elevation 

 than any other part of the coast Ave have seen, or it would have apjjeared 

 above the barrier."* 



This ice cliff or barrier was followed by Captain Ross as far as 198° 

 W. longitude, and found to preserve very much the same character during 

 the whole of that distance. On the lithographic view of this great ice 

 sheet given in Ross's work it is described as " Part of the South Polar 

 Barrier, to 180 feet above the sea-level, 1,000 feet thick and 450 miles 

 in lenajth." 



A similar vertical wall of ice was seen by D'Urville, off the coast of Adelie 

 Land. He thus describes it ; " Its appearance was astonisliing. We per- 

 ceived a cliff having a uniform elevation of from 100 to 150 feet, forming 



a long line extending off to the west Thus for more than twelve 



hours we had followed this wall of ice, and found its sides everywhere per- 

 fectly vertical and its summit horizontal. Not the smallest irregularity, not 

 the most inconsiderable elevation, broke its uniformity, for the twenty leagues 

 of distance which Ave folloAved it during the day, although we passed it occa- 

 sionally at a distance of only two or three miles, so that we could make out 

 with ease its smallest irregularities. Some large pieces of ice were lying 

 along the side of this frozen coast; but, on the whole, there was open sea in 

 the offing [au large]."! 



There can be no doubt that these ice barriers described by Ross and 

 D'Urville are extremely interesting, since they have far more the aspect of 

 a "Polar ice-cap" than anything observed in the Arctic seas. At all events 

 they have been frequently described as such by writers on the Glacial epoch, 

 and freely used to explain and illustrate the condition of things during the 

 " Great Ice-Age." It will be desirable, therefore, to introduce at this point 

 a few words as to the nature and probable origin of these extraordinary ice 

 masses. 



First, however, the peculiar climatic conditions of the Antarctic Polar 



* I. c, Vol.1, pp. 217-219. 



+ Voyage au Pole Sud et dans I'Oceauie sur lea Corvettes I'Astrolabe et la Zelee, execute par Ordre du Roi 

 pendant les Annees 1837, 1838, 1839, 1840, sous le comniandemeiit de M. J. Dumont D'Undlle, Capitaine de 

 Vaisseau. Histoire du Voyage, Tome A'lII. pp. 175, 176. 



