334 SCIENCE PROGRESS 



down, for a terminal moraine has been observed at 10,000 ft. and 

 erratics have been traced down to 9,800 ft. 1 Similar evidence is 

 afforded by Mount Ruwenzori 2 and Mount Kilimandjaro. 3 



Thus, to whatever region we turn, our inquiries elicit the 

 same facts. Alike in Northern Europe and Southern Australia, 

 in the Peruvian Andes or the isolated cones of Central Africa, 

 the evidence points to a considerable lowering of temperature in 

 comparatively recent times, corresponding with the last glacial 

 epoch. Thus the great Ice age clearly deserves its name ; it 

 affected the whole of our planet, and can scarcely have failed to 

 influence in a high degree the history of its inhabitants. 



Of late years investigations bearing, if possible, even more 

 immediately on our subject, have been directed to the succession 

 of events, or the inner history, of the glacial epoch. 



In the British Isles the mountains are so inconsiderable, and 

 the volume of the ice was so great, that secondary effects are lost 

 in the general result, and detailed research is conducted under 

 exceptional difficulties. In the Eastern Alps, on the other hand, 

 both the relief of the ground and the magnitude of the glaciers 

 are such as seem to promise a ready response to fluctuations 

 of temperature, and this under conditions favourable to a 

 permanent record of their effects. Nature seems, indeed, to 

 provide in them a delicate registering thermometer. It was 

 in this way, at least, that they appealed to the sagacity of 

 Prof. Penck, 4 one of the most distinguished investigators of 

 glacial phenomena at the present day ; and it was on the 

 Eastern Alps, therefore, that he first concentrated his attention. 

 Let us follow him into this region. A photograph given in his 

 great work (loc. cit., opp. p. 90) represents one side of the valley 

 of the Steyr. On close examination it will be seen to display a 

 number of parallel terraces, almost horizontal, and running with 

 great regularity in the same direction as the valley. The lowest 

 of these terraces (zv) forms a broad field through which runs the 

 poplar-bordered road from Steyr to Sierning. It descends by a 

 steep slope, about 50 ft. in height, to the river. Nearly 70 ft. 



1 J. W. Gregory, "The Glacial Geology of Mount Kenia," Quart. Journ. Geol. 

 Soc, 1894, vol. 1. p. 521. 



1 J. W. Gregory, "The Geology of Mount Ruwenzori, 1895," Quart. Journ. 

 Geol. Soc. 1895, vol. li. p. 676. 



3 H. Meyer, Ostafricanische Gletscherfahrten. 



4 A. Penck and E. Bruckner, Die Alpen im Eiszeitalter, 8vo, Leipzig, 1901 — 

 1908, issued in parts, not yet complete. 



