THE ANTARCTIC REGIONS. 329 



deflected northward after taking a westerly course along the edge 

 of the southern barrier of Ross ? 



Of the arguments that have been advanced in favor of consid- 

 ering Antarctica as a vast continent buried deep beneath its cov- 

 ering of snow and ice, the most plausible are those which re- 

 late to the construction and form of the oceanic bottom within 

 the region of the southern ice and the character of the ice itself. 

 More explicitly stated, they are : (1) The shallowing of the sea 

 toward the so-called antarctic tract an approach to the borders 

 of a continent and the occurrence of what are stated to be sub- 

 continental or terrigenous deposits, conditions that are well em- 

 phasized by Murray; and (2) the heavy massing of ice, which 

 could seemingly not be other than of glacial origin. Ross found 

 the depth of water opposite the barrier which stopped his farthest 

 passage southward reduced to two hundred and fifty and one hun- 

 dred and fifty fathoms, so that manifestly there was here a true 

 shallow ; somewhat similar results were obtained at a few other 

 points along the barrier front. But it can be pertinently asked. 

 In what special way would the approaches to an archipelago dif- 

 fer from those of a continent ? With this special evidence of 

 shallowing before him, Ross still believed in the probability of 

 non-continental conditions, and he was in a measure justified in 

 his belief by the fact that at many other points not far from 

 the front of the barrier the lead indicated depths of from four 

 thousand to six thousand feet, and even more. 



The massiveness of the ice is in a condition which, so far as 

 it is known to us, belongs exclusively to glacial formation ; i. e., 

 none but land ice is known to assume this form. The evidence 

 which it offers, therefore, favors the notion of the existence of 

 large terrestrial areas or gathering basins. Yet it is by no means 

 impossible, or even improbable, that with the low summer tem- 

 peratures which prevail in the antarctic tracts and the continu- 

 ousness of fogs and clouds, the surface of the sea might of itself, 

 through ages of precipitation and of comparatively little melt- 

 ing, build itself up in mountains of ice, hundreds or even thou- 

 sands of feet in thickness. This view has, indeed, been held by 

 some physicists, and no facts that are accessible to us are really 

 incompatible with it. The uniformity of the table surface of the 

 ice, which appears to be uninterrupted in places for hundreds of 

 miles, combined with the fact that it only occasionally shows an 

 undulating or rising surface back of it to mark out a land relief, 

 is in itself a suspicious circumstance. This is very different 

 from what we find in Greenland, the largest area of positive gla- 

 ciation with which we are acquainted, and which certainly car- 

 ries with it the constructional type of a continent. Whether 

 seen from the east, south, west, or northwest, the relief line is 



VOL. L. 26 



