the same result for the more recent periods, namely, a position of the North Pole at the beginning of the Tertiary in the neighbourhood of the Aleutian Islands, and from then a wandering towards Greenland, where it is to be found in the Quaternary. For these periods great relative discordances do not appear. But it is quite otherwise for the periods preceding the Cretaceous. Not only do the views of well-known authorities differ very widely, but as a consequence of the disregard of continental displacements the reconstructions lead to hopeless contradictions, indeed contradictions of such a kind that they form an absolute obstacle to any conceivable position of the pole at all.
The Permo-Carboniferous glacial deposits of the southern hemisphere form the most serious of those obstacles. These traces of ice-action are found on all the southern continents, sometimes with such surprising clearness that the direction of movement of the ice-masses can be read from the scratches on the polished surfaces of the rocks. These traces were first and best studied in South Africa, but they were then also discovered in Brazil, Argentina, in the Falkland Islands, in Togoland, in the Congo area, again in India, and in West, Central and East Australia.[1] If we merely place the South Pole in the conceivably best position (50° S. 45° E.) in the midst of these traces of ice, the remotest traces of land-ice in Brazil, India and Eastern Australia would possess a geographical latitude of not quite 10°, that is, a complete hemisphere of the earth was buried beneath the ice, and had therefore also the polar climate necessary for that purpose. The other hemisphere, however, the Carboniferous and Permian deposits of which are in most areas very well known, does not show sure traces of glaciation, but on the
- ↑ Compare the map in Dacqué, Grundlagen und Methoden der Paläogeographie. Jena, 1915.
