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SCIENCE 



[N. S. VoL.XXXn. No. 818 



than those stretching east and west. He is 

 unable to explain satisfactorily why it is that 

 at some places, like the South Shetlands, there 

 are huge masses of ice, while at others, like 

 Snow Hill, there are stretches of ground 

 which are ice free. But this last condition 

 may, in some way, be due to the storms. He 

 is also quite unable to account for the various 

 phenomena connected with the ice cap of 

 East Antarctica, as we know nothing about it 

 beyond the few facts obtained by the British 

 expeditions in "Victoria Land, and that von 

 Drygalski observed the edge of the ice cap ad- 

 vancing very slowly in Kaiser-Wilhelm Land. 

 Dr. Nordenskjold considers the ice cap of 

 East Antarctica the greatest geographical 

 problem in the world, and that nothing will 

 be really known about it, until some expedi- 

 tion pushes in some distance from some place 

 on its sea front, such as Wilkes Land. The 

 Great Ice Barrier he looks on as remarkable 

 but not unique, as he himself discovered a 

 similar, if smaller, formation, which he calls 

 " shelf-ice," on the coast of King Oscar Land. 

 He was not able to ascertain whether this had 

 any motion. The mode of formation of this 

 shelf -ice is still uncertain. The ice conditions 

 in the south are decidedly different from those 

 in the north. The great mass of ice rests un- 

 doubtedly on land, and the ice caps are much 

 bigger. And this mass of ice Dr. ISTorden- 

 skjold thinks is due mainly to the semi-oceanic 

 climate, since Antarctica is surrounded by 

 water, and there is much precipitation. But 

 it is mainly due to the very cold summers : 

 at Snow Hill, for instance, more snow fell in 

 summer than in winter. Antarctic tempera- 

 tures, however, vary in diilerent places. The 

 climate was not always as cold as now, as 

 fossils have been found, probably of Tertiary 

 times, which belong to a subtropical climate. 

 They link West Antarctica to South America. 

 The penguins already lived in the south in 

 Tertiary times, and have gradually adapted 

 themselves to . the changed conditions. There 

 are no land animals whatever in Antarctica, 

 and one reason may be that, at one period, the 

 ice covered absolutely every bit of land, and 

 killed off any life there may have been. 



All the lands so far mentioned, barring 

 Iceland, Dr. Nordenskjold considers true 

 polar, with the ice as their chief characteristic. 

 Those described in the second half of his book 

 he looks on as semi-polar. These have some- 

 times polar characteristics, but sometimes 

 quite different characteristics. Snow and ice 

 play their part, but mainly in winter ; in sum- 

 mer they must be looked for almost wholly in 

 mountainous regions. 



Of southern South America, Dr. Norden- 

 skjold speaks largelyfrom his own explorations. 

 Along the western coast there is the mountain 

 range of the Andes, to the west of which 

 extends a string of islands, with deep navi- 

 gable channels behind them, and how these 

 were formed, Dr. Nordenskjold hesitates to 

 say, but he evidently disbelieves that they 

 were scooped out by ice. On the contrary, 

 the fiords and valleys running inland he 

 thinks were at least to some extent formed by 

 glaciers, and he judges that these lands were 

 at one period largely ice capped. Even to-day, 

 in some places, glaciers reach to the sea. On 

 the eastern coast, on the contrary, there is a 

 plateau formation, which gradually slopes 

 from the mountain to the sea. Much of this 

 plateau is covered with masses of broken stone 

 (gerbll). Dr. Nordenskjold thinks these may 

 be due to great glacial rivers, which kept 

 changing their courses, accompanied, as in 

 Iceland, with some volcanic action : still he 

 leaves the matter problematical. There are 

 many moraines also, which prove a former 

 great extension of the glaciers, but nothing 

 which shows that there was a true ice cap. 

 Dr. Nordenskjold, while in Patagonia, heard 

 of a find by some workmen of a skin in a 

 cave. He visited the place and dug out him- 

 self a piece of this skin, covered with long 

 reddish hair. It turned out to belong to a 

 Grypotherium, a giant sloth of, probably. 

 Pleistocene times, and this discovery led later 

 to others. There are two native tribes in 

 Patagonia : the Onas to the east, the Yaghans 

 to the west, and about these Dr. Nordenskjold 

 makes an important new suggestion. Usually 

 they are ranked as the lowest of races, because 

 they have not invented clothes. Dr. Nor- 



