February i8, 1909J 



NA TURE 



461 



treme views on some glacial questions, and holds that 

 the progressive advance of civilisation to the temperate 

 regions from the tropical and subtropical zones is one 

 manifestation of the spread of a milder climate across 

 the earth. Of the suggested theories of glaciation he 

 regards CroU's as the most seductive, but admits that 

 it has fallen with all the rest ; nevertheless, he still 

 argues with Croll's wild estimate that the ice at the 

 South Pole is six miles thick, as if that notion were 

 worth serious consideration. Arrhenius's view that 

 glaciation is due to variations in the atmosphere 

 Arctowslvi rejects as being far from a satisfactory 

 explanation of the facts. His own idea is that the 

 climatic change was due to a variation in the heat 

 supply from the sun. 



The memoir begins with a description of the glacial 

 phenomena of the neighbourhood of the Magellan 

 Stiaits, supplementing the valuable observations in this 

 area by Dr. Otto Nordenskjold. The second part of 

 the memoir is a valuable contribution to the tectonic 

 and glacial geology of Gerlache Strait. He describes 

 that strait as a tectonic valley, but he is doubtful (p. 

 34) whether it was formed as a syncline or a rift 



Fig. 2. -View of Royal Sound, Kerguekn. 



valley. In dealing with the Antarctic lands, he notes 

 the various forms of the name Antarctica, and suggests 

 that the western section should be called " Westantar," 

 as " Antar " includes all that is common in the various 

 forms of the name Antarctica. 



In his account of the tabular icebergs, M. Arctowski 

 is emphatic as to their identity with the fioebergs of 

 the Arctic, and he quotes with approval Greeley's ex- 

 cellent statement of the formation of fioebergs. He 

 discusses the question of glacial erosion, and says 

 that his observations show that erosion by glaciers is 

 a mere " minime " ; but he remarks that ice has 

 powers of deeper erosion than rivers, as it can erode 

 below sea-level, whereas a river cannot excavate deeper 

 than the level of its mouth. His report concludes with 

 an interesting discussion on the extent of the refriger- 

 ation of climate indicated, according to the theory he 

 accepts, by the former extension of glaciers. 



.'\ further instalment of the reports of the German 

 Antarctic Expedition includes three instructive memoirs 

 on Kerguelen. Dr. Werth records his additions to 

 the geography of the island during a year's residence, 

 in 1 90 1 and 1902, at a station erected on the Gauss 



NO. 2051, VOL. 79] 



Peninsula in south-eastern Kerguelen to obtain ob- 

 servations for comparison with those simultaneously 

 made by the Gauss. Emil Philippi, the geologist ol 

 the expedition, records the results of his excursions 

 ashore during the stay of the Gauss at Kerguelen, and 

 Dr. Reinisch describes in detail the rock specimens 

 collected there. 



.Since the discovery of the archipelago by Kerguelen 

 in 1772, and the establishment of its insular nature by 

 Cook in 1775, it has been visited by many expeditions, 

 including the Erebus and Terror, the Challenger, the 

 Gazelle and the ]'aldivia, and by private naturalists, 

 such as Hall, the .Australian ornithologist. It has 

 also been the resort of seal and whale fishers. Never- 

 theless, and in spite of the important contributions of 

 the expedition' under Drygalslvi, Kerguelen is still im- 

 perfectly known. Dr. \Verth made numerous excur- 

 sions from the station, but the main interior and its 

 glaciers and mountains, were inaccessible to him, and 

 the southern and western coasts he describes as still 

 practically unknown. Dr. Werth's range of work v/as 

 restricted by the difficulties of transport. His party 

 had at first to carrv all their equipment on their backs, 

 and were therefore limited to e.xcur- 

 sions of about five days' duration. 

 Later on he used dogs, and as each 

 dog carried a pack of ^ twenty 

 pounds, it could take its own 

 rations for ten days, and some 

 supplies for the explorers. In the 

 later part of the stay on the 

 island exploration was unfortu- 

 nately prevented by illness. 



The chief island of the Kergue- 

 len Archipelago is only 130 square 

 g-eographical miles, and it is 

 divided into three divisions. The 

 western coast lands are still little 

 known, and may contain some 

 centres of recent volcanic activity. 

 The central highlands, running 

 from north-west to south-east 

 across the island, include two 

 high ice-covered plateaus, and 

 culminate at their southern end 

 in Mount Ross, a volcano with a 

 well-preserved crater and 1990 

 metres high. The third section 

 includes the country on the east- 

 ern parts of the island ; it is 

 deeply indented by the sea, and 

 is mainly lowland, but it includes one inde- 

 pendent mountain complex and some wide plateaus. 

 The solid geology of Kerguelen is disappointing. It 

 consists of nothing but a vast dissected sheet of basalts, 

 with their associated tuffs, and various glacial and 

 alluvial deposits. There are older trachytic and phono- 

 litic lavas, of which the German expedition obtained 

 traces in beds of sanidine sand. There are no known 

 pre-volcanic sedimentary rocks, and whether Kerguelen 

 is a continental or an oceanic island is left undecided. 

 The physical geography of the island is, therefore, its 

 chief interest. For a land in the latitude of only 

 48°-5o°, it has the remarkably low snow-line of 1850 

 feet, and its central highlands are covered by an ice 

 sheet which Dr. Werth has named after Richthofen. 

 There is abundant evidence that the glaciers were more 

 extensive, at a date that Dr. Werth calls " diluvial," 

 which may be more recent than the chief glacier 

 e.xtension in north temperate regions. The glaciers cer- 

 tainly formerly reached the present sea-level, and 

 appear to have continued some distance over what 

 is now the sea floor. It is, therefore, disappointing 

 that there is no certain evidence as to the post-Glacial 



