70 DISCUSSIONS IN CLIMATOLOGY. 



united and combined by an extension of the ice- 

 sheet." 



"Various patches of Antarctic land," he continues, 

 " are now known with certainty, most of them between 

 the parallels of 65° and 70° S.; most of these are com- 

 paratively low, their height, including the thickness of 

 their ice-covering, rarely exceeding 2000 to 3000 feet. 

 The exceptions to this rule are Victoria Land and the 

 volcanic chain, stretching from Balleny Island to 

 latitude 78° S.; and a group of land between 55° and 

 95° west longitude, including Peter the Great Island, 

 Alexander Island, Graham Land, Adelaide Island, and 

 Louis Philippe Land. The remaining Antarctic land, 

 including Adelie Land, Clairie Land, Sabrina Land, 

 Kemp Land, and Enderby Land, nowhere rises to any 

 great height."* 



There is another class of facts which shows still more 

 conclusively the probably low flat nature of most of the 

 Antarctic regions. I refer to the character of the great 

 ice-barrier, and the bergs which break off from it. The 

 icebergs of the southern ocean are almost all of the 

 tabular form, and their surface is perfectly level, and 

 parallel with the surface of the sea. The icebergs are 

 all stratified; the stratifications running parallel with 

 the surface of the berg. The stratified beds, as we may 

 call them, are separated from each other by a well- 

 marked blue band. These blue lines or bands, as Sir 

 Wyville Thomson remarks, are the sections of sheets 

 of clear ice; while the white intervening spaces between 

 them are the sections of layers of ice where the parti- 

 cles are not in such close contact and probably contain 

 some air. The blue bands, as Sir Wyville suggests, 

 probably represent portions of the snow surface which 



* "Lecture on Antarctic Regions" (Collins, Glasgow, 1877); 

 " Nature," vol. xv. 



