principles had I hoy never seen a glacier, yet they failed to 

 appreciate them because of the adverse suggestion of the 

 inertness of glaciers of to day. At every turn they were 

 confronted with the effects of glacial decadence, hut they did 

 not perceive the dynamical significance of such decadence. 

 It had been seen by them quite early in the discussion that 

 the present glaciers of the temperate regions were insig- 

 nificant, and it seemed thus quite natural to go for pilgrim- 

 ages to the Alps, or to the Polar Regions, and there to 

 find the clue to past ice action by studying the Ice Caps 

 of such countries as Greenland and Spitzbergen. Then they 

 fell into the serious error of mistaking the present Polar 

 Ice Caps for Ice Floods, simply because such Ice Caps were 

 much larger than the Alpine glaciers to which they had 

 been accustomed. From the observations there made they 

 commenced to construct a scheme whereby both recent 

 glacial motion and corrosion might be explained, despite 

 the glaring evidence to the contrary of glacial inactivity 

 in the same regions. The error was perhaps natural, but 

 disastrous the more so as their own observations, had proved 

 that both the last Ice Flood and the present stage of 

 diminished glacial volume were due to cosmopolitan causes. 

 It was disastrous because the dynamical laws involved are 

 unchangeable and any attempt to deny them is unscientific. 

 The glaciers of the Polar regions are certainly large, but 

 they are mere pigmies compared to the recent Ice Caps as 

 revealed by the wealth of deglaciated valleys in the same 

 regions. It was thus unsafe to draw detailed conclusions 

 as to the past glacial motion by a mere study of the present 

 Ice Caps. One might as well expect to understand the 

 action of the recent glaciers hy a consideration of large ice 

 cubes in a laboratory. 



An analogy borrowed from ordinary stream action may 

 help us here, if the meaning is not already clear enough- 

 It is well known from the studies of Hutton, Playfair, 



