Page:Popular Science Monthly Volume 60.djvu/224

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from Dougherty Island and Peter Island in the southern Pacific. Meteorological evidence supports the idea that the Antarctic is still a continent geographically, and that the center of the land is not coincident with the south pole, but is in the eastern part of the area.

The available evidence appears to be decidedly in favor of Sir John Murray's theory, though the question cannot be definitely settled until the range of the land has been mapped. This task may be facilitated by the guidance as to the probable trend and position of the coasts, that is given by the principles of geomorphology.

If the current theory of the structural unity of the Pacific ocean be correct, then that ocean must be bounded on the south by a coast of the 'Pacific type.' With one exception in Central America the whole of the known coasts of the Pacific belong to what Suess has called the 'Pacific type.' The main character of this form of coast is that the trend is determined by mountain ranges running parallel to the shore. In the South Pacific this type is well exemplified by New Zealand on one side and by the Andes of South America on the other. In southern Patagonia the Andes are turned from their meridional course and run eastward across Terra del Fuego. The tectonic line of the Andes is then apparently bent suddenly southward and reappears in Graham Land. It is probably continued round the southern Pacific, meeting the known end of the New Zealand line near Mounts Erebus and Terror.

The theory of the structural unity of the Pacific is sufficiently established to render it probable that Cook was close to land when he turned back from his furthest south in the South Pacific (71°S. 123°E.), that the 'ice-barriers' of Ross and Bellingshausen are both the fronts of glaciers flowing from highlands to the south; that there is a land connection of the Pacific coast type running from Ross's ice barriers northeastward to Graham Land; and that Victoria Land is connected to Wilkes Land by a broad bight.

There are no such data for predictions as to the distribution of land and water in the German and Scotch areas of work. For Wilkes Land and the lands that may extend thence westward towards Graham Land are no doubt plateau countries bounded to the north by coasts of the 'Atlantic type'; and the trend of such coasts is not determined by simple continuous tectonic lines. That Wilkes Land and Geikie Land repeat the structure of southern Australia is rendered probable by the geological collections of all the expeditions from Wilkes to the 'Southern Cross.' The westward extension of this land line has probably the same structure, and it is accordingly impossible to predict how far the Weddell cuts into the Antarctic lands.

The principles of geomorphology not only suggest the external shape of 'Antarctica' but also its internal relief. It is probable that it