PHYSICAL AND CLIMATAL CONDITIONS. 81 



near to the ocean to receive and condense its burden of 

 watery vapour. Tliis is the cause of the present state of 

 Greenland, and similar conditions would account for that 

 great ( Jordilleran glacier which Dr. G. M. Dawson has 

 shown existed in Pleistocene times on the mountains of 

 British Columljia, and for the Laurentide glacier or local 

 glaciers which it is known existed on the Laurentian * 

 highlands of Canada and even on the extension of the 

 Appalachian mountains in eastern Canada.f On this 

 subject I may ([uote here the conclusions of the well- 

 known Itussian geograi)her, Von Woeickoff, J as summarized 

 in a partial translation puljlished in tlie " CanacHan 

 Naturalist " in 1882. I ought ])erhaps to a})ologize for 

 repeating here connnon and cNcn trite conclusions of 

 physical geography ; but my excuse must be the neglect 

 with wliich they have been treated by so many geologists, 

 and the extent to which theories altogether at variance 

 with them have l)een promulgated. 



I may say at the outset that I fully agree with the 

 views as to the motion of glaciers contained in the sub- 

 joined extract : 



" The fuller consideration of the physical properties of 

 glacier ice leads to essentially the same conclusions as 

 those to which Forbes was led forty-one years ago, by the 

 study of the larger phenomena of glacier motion, that is, 

 that the motion is that of a slightly viscous mass, partly 

 sliding upon its bed, partly shearing upon itself under the 



* Notes on Post-pliocene, 187*2. See also a paper by McGee in the 

 the Proc. American Association (Bosti/i-, 1880, p. 447), and Dana in 

 American Journal of Science, 1872. 



+ Chalmers' Glaciation of N. New Brunswick, etc., Trans. R.S.C. 

 1886. 



X Geological Society, Berlin, 1881. 



