part 1] ANNIVERSARY ADDRESS OF THE PRESIDENT. Ixxxi 



bare land amid mountains of ice. The recent investigation of 

 North-East Greenland has revealed some remarkable instances of 

 this kind ; others are known in Grinnel Land, Ellesmere Land, and 

 the neighbouring archipelago l ; Spitsbergen affords abundant illus- 

 trations ; and even in Antarctica some low-lying ice-free tracts have 

 been observed. The possibility of this great inequality of condition 

 in contiguous tracts of similar altitude and structure is a strong 

 distinction between glacial action and the effects of atmospheric 

 weathering, or of submergence beneath water, both of which bring 

 about comparative equality of circumstance throughout the tract 

 at any particular level. Of prime consequence on the plains, this 

 ' localization of effect ' has undoubtedly left its mark also on the 

 hill-regions, where some tracts have evidently been thoroughly 

 scoured by the glaciation, while others, close by, have been hardly 

 touched. The tracing-out of these varying effects in detail on the 

 high ground still affords an interesting and comparatively un- 

 worked field for the interpretive glacialist. 



Post-Glacial Features. 



Though so much of our country is shaped, as we have seen, by 

 the drifts, we must take into account that the finishing touches to 

 the features have been wrought by the agencies in operation during 

 post-Glacial and recent times. In the new-made land, as for 

 example, Holderness and West Lancashire, the drainage-system is 

 entirely post-Grlacial; as it is also in most of the thickly drift-covered 

 country of the Eastern counties, the Cheshire and Flintshire low- 

 land, and Wirral; and these areas afford an opportunity for gauging 

 roughly the time that has elapsed since the glaciation by the 

 amount of erosive work performed in it. Indeed, there is some 

 hope that intensive study of this erosion, and of the small drift- 

 basins infilled with freshwater deposits, may eventuaby yield 

 numerical data for the time- interval, analogous to those which have 

 been obtained in Sweden from the researches of our esteemed 

 Wollaston Medallist, Prof. G. J. De Greer, whose work we have 

 honoured to-day. It is very notable, however, in these areas how 

 much the present aspect of the drift depends upon the drainage- 

 slope ; in tracts of sluggish or clogged drainage the glacial 



1 For a useful and well-illustrated review of the conditions in Arctic lands, 

 with copious references to literature, see W. H. Hobbs, ' Characteristics of 

 the Inland Ice of the Arctic Regions ' Proc. Amer. Phil. Soc. vol. xlix (1910) 

 pp. 57-129 & pis. xxvi-xxx. 



VOL. LXXVI. f 



