THE ANTAECTIC QUESTION- — MACHAT. 463 



This depression would come near the Kemp and Enderby Lands; 

 but, near the front of the glacier, a rise of the bottom proves the ex- 

 istence of a continental plateau. To the southwest of Graham Land, 

 at the edge of the coast plateau, where the Belgica drifted, on the 

 contrary, the depths appear to be less. In latitude Tl° S. along 

 Alexander I Land, the depth is about 2,700 meters.'^ To multipl}^ 

 the soundings during the coming expeditions all along Antarctica 

 would add to our present vague knowledge in regard to the rela- 

 tionshiiD in structure between this land and the Andes. 



A further study of the sea currents with special reference to their 

 movements and their fauna is desired, for up to the present time 

 there have been only general observations or local data of temporary 

 value. The surface temperature stands at about zero nearly the 

 whole year. That of the bottom is remarkably low and increases as 

 the ice is approached. From — 0.3° in the Atlantic-Indian Valley 

 of the Scotia, it reached a minimum of — 0.6° in Gerlache Strait at 

 a depth of 3,690 meters; and the Nordenskjolcl expedition at a depth 

 of 1,450 meters in Bransfield Strait found a temperature of — 1.65°, 

 the lowest then recorded.^ Since then the Southern Cross publica- 

 tions record — 2.3° as the mean temperature of the sea water under 

 the Ross Barrier. These very cold bodies of water are peculiar to 

 very great depths. The observers on the Gauss found between the 

 cold strata at the surface and at the bottom the presence of a stratum 

 of water of nearly -\-l° , Salter than the surface and less dense than 

 the bottom, due probably to currents from the distant Temperate 

 Zone. Drake Strait, where Nordenskjold observed not less than 

 -|-1.9° at 1,400 meters, and the South Atlantic, where the Scotia met 

 temperatures of from +0.1° to -f-0.5°, would mark on the west 

 coast of Antarctica the northern limit of the polar bottom waters. 

 As for the salty condition, the Belgica expedition found it to slightly 

 diminish toward the south, due to the melting ice. Annual varia- 

 tions are slight, the maximum being during the winter, as would be 

 expected. 



MM. Arctowski of the Belgica and Matha of the Franqais made 

 repeated observations regarding the density of the sea water, which 

 are beyond the scope of this paper. Matha also studied the tides. 

 From a maximum height of 2 meters, they have shown at Port Char- 

 cot a daily flood tide to be compared to that of Indo-China (onlj^ 

 one flood tide each twenty-four hours, or two irregular ones). 



ANTARCTIC CLIMATE. 



Climatic conditions in the Antarctic regions have received the 

 special attention of explorers. Observations have been numerous, 



«De Gerlache: Op. cit., p. 162. 

 ^O. Nordenskjolcl: Op. cit, p. 191. 



