20 AN ABERRANT DRIFT 



in the proceedings of the Geological Societies of 

 England and the Continent. 



Notwithstanding that the bulk of the superficial 

 drifts covering the country can be thus accounted for, 

 there is nevertheless a residue which cannot, in my 

 opinion, be referred to any of the causes assigned for 

 the formation of these deposits. Such likewise was 

 the conclusion which Sir Eoderick Murchison 1 was 

 led to form, though he failed to eliminate some of the 

 established Drifts, and ascribed them all generally to 

 a wave of translation. Professor James Geikie has 

 also noticed one form of this Drift, but adopts in 

 explanation of its origin a suggestion of Darwin's 

 that it is to be attributed to the cold and snow of the 

 Glacial period. Though we thus difTer in our interpre- 

 tation of its origin, the essential fact remains of the 

 recognition of an aberrant form of drift. 



I have named this residue the " Kubble-Drift," as it 

 is unstratified and complex and without the order and 

 unity which distinguishes the fluviatile and marine 

 drifts. The debris is as a rule angular and sharp, nor 

 is any portion of it glaciated or transported from 

 beyond the immediate vicinity of the place of their 

 occurrence, as is the case with beds of glacial origin. 



$ 4. THE KUBBLE-DRIFT : ITS VARIOUS PHASES. 



This Drift not only varies according to the nature 

 of the ground, but also in accordance with the inci- 



1 Quart. Journ. Geol. Soc., vol. vii. p. 349. 



2 Prehistoric Ewrope, p. 140. 



