Manchester Memoirs, Vol. Ixii. (1918), No. 9. 13 



this country in post-Glacial times is far from being of a satisfactory 

 nature. 



As already pointed out by Bather, facetted pebbles in them- 

 selves cannot be regarded as evidence of steppes, or of a dry climate. 

 The conditions at the close of glaciation in any country must have 

 been favourable to the production of such pebbles. The land was 

 bare and exposed to winds ; its surface was strewn with boulders 

 and pebbles, and associated with them was an abundance of sand. 

 Coupled with the fact that the pebbles had been previously fractured 

 by frost and thaw, as has been shown to be the case in the examples 

 dealt with in this paper, the above conclusion seems to provide the 

 necessary explanation for the presence of facetted and wind-worn 

 pebbles in association with Drift deposits. 



Summary 



In this paper facetted and wind-worn pebbles are described from 

 three localities near Manchester, and from three others in the Wirral 

 peninsula ; in one case below the Lower Forest-bed of Cheshire. 



The mode of occurrence shows the pebbles to be post-Glacial 

 and pre-Neolithic in age. They have been acted on by sand-blast 

 at some time after the deposition of the Glacial beds on which they 

 lay, and in this respect they agree with similar pebbles found in 

 North Germany and in North America. 



A large number of the pebbles have been split or fractured 

 before being acted upon by blowing sand, and it is suggested that 

 the splitting is due to frost-action. 



It is suggested that an intimate connection exists between the 

 period of wind-erosion and the laying down of the Shirdley Hill 

 Sand by aeolian action in early post-Glacial times. This sand usually 

 rests on the Boulder-clay and is sometimes separated from it by a 

 gravel-bed. The latter and the several deposits of facetted pebbles * 

 appear to occupy a somewhat analogous position with regard to the 

 Drift to that of the basement bed, or " Steinsohle," of the Loess 

 of the North German Plain, where facetted pebbles are of frequent 

 occurrence. 



The presence of the pebbles below the Lower Forest-bed of 

 Cheshire is of importance as it pushes the period of wind-erosion well 

 back in post-Glacial times, as the forest is prior to the estuarine 

 deposits of the 25-foot submergence, and the latter are regarded as 

 very early Neolithic. 



It is concluded that the facetted pebbles do not furnish con- 

 clusive evidence of a dry climate or steppe conditions obtaining in 

 this country in post-Glacial times. 



