52 BULLETIN OF THE 



But, there is a subject of great interest likely to be elucidated by our 

 investigation, — the contrast of the deep-sea faunae of the northern with 

 those of the southern hemisphere. Judging from what Australia has 

 already brought us, we may expect to find that the animal world of the 

 southern hemisphere has a more antique character, in the same way as 

 North America may be contrasted witli Europe, on the ground of the 

 occurrence in the United States of animals and plants now living here, 

 the types of which are only found fossil in Europe. 



A few more words, upon another subject. During the first three 

 decades of this century, the scientific world believed that the erratic 

 boulders, which form so prominent a feature of the surface geology of 

 Europe, had been transported by currents arising from the rupture of 

 the barriers of great lakes among the Alps, or started from the north 

 by earthquake waves. 



Shepherds first started the idea that within the valleys of Switzer- 

 land these huge boulders had been carried forward by glaciers, and 

 Swiss geologists, Venetz and Charpentier foremost among them, very 

 soon proved that this had been the case. This view, however, remained 

 confined to the vicinity of the Alps in its application, until I suggested 

 that the phenomenon might have a cosmic importance, which was 

 proved when I discovered, in 1810, unmistakable traces of glaciers in 

 Scotland, England, and Ireland, in regions which could have had no 

 connection whatever with the elevation of the Alps. Since that time 

 the glacial period has been considered by geologists as a fixed fact, 

 whatever may have been the discrepancies among them as to the ex- 

 tent of these continental masses of ice, their origin, and their mode of 

 action. 



There is, however, one kind of evidence wanting to remove every 

 possible doubt that the greater extension of glaciers in former ages was 

 connected with cosmic changes in the physical condition of our globe. 

 All the phenomena related to the glacial period must be found in the 

 southern hemisphere with the same characteristic features as in the 

 north, with this essential difference, that everything must be reversed; 

 that is, the trend of the glacial abrasion must be from the south north- 

 ward ; the lee side of abraded rocks must be on the north side of hills 

 and mountain ranges, and the boulders must have been derived from 

 rocky exposures lying to the south of their present position. Whether 

 this is so or not has not yet been ascertained by direct observation. I 



