DRIFTS OF FLAMBOROCQK UEAD. 413 



Tliosc pebbles are generally of small size, say between that of a 

 walnut and a clenched fist; but a few larger examples were found, 

 the largest being a boulder of basalt 12 by ,5 by 3 inches, and another, 

 subangular, of porphyritic felstone 7 by 4 by 3 inches. Most of tlie 

 pebbles were well rounded, but a few were subangular. One striking 

 difference is apparent between these pebbles and the erratics of the 

 overlying drifts ; for while in the drifts of this locality fully 80 per 

 cent, of the stones have been derived from the Carboniferous rocks, 

 Mountain Limestone being particularly abundant, no Mountain Lime- 

 stone nor other recognizable Carboniferous rock was found among 

 the pebbles of the old beach. IVom this it would appear that at 

 any rate no glaciers from the Pennine chain, by which the Carboni- 

 ferous debris of the drift seems chietly to have come, reached the east 

 coast at this time. 



Though there can bo little doubt of the ice-borne character of 

 these pebbles, it is an open question whether they have been carried 

 to this beach by floating ice or have been derived at second hand 

 from an older glacial deposit. If the latter view be correct the 

 Cliff-beds ma}' well be considered inter-Glacial ; but I think that 

 the evidence tends to show that it is not correct. 



If the supposed earlier Glacial deposits capped the old cliff, traces 

 of them could scarcely fail to appear in the landwash, in which, 

 however, there are no erratics ; while the difficulties which arise in 

 supposing that such beds were submerged off the coast beyond the 

 Chalk platform are very great. If there had been in Yorkshire an 

 inter-Glacial period of so long duration as to allow the sea to cut 

 back a line of hard chalk cliffs with a broad tidal platform at 

 their base, its effect in other areas must have been equally marked. 

 Yet I am aware of no evidence for such an interval among the 

 drift-deposits of the east of England. Traces of a line of buried 

 cliffs, evidently the continuation of that of the Sewerby section, have 

 been found along the inner edge of the ^yolds, not only along the 

 Holderness margin *, but also in Lincolnshire t, the more southerly 

 localities being within thirty or forty miles of the Norfolk coast, 

 lint in every case the drift is found to be banked against and over 

 these cliffs, and no evidence is forthcoming for the existence of a 

 Boulder-clay prior to the erosion of this old coast-line. 



It is, I think, generally agreed that the Norfolk sections contain 

 in the Forest-bed series and the overlying marine and freshwater 

 horizons the fullest record extant in England of the period immedi- 

 ately antecedent to the Great Ice Age, and also of the earlier stages 

 of the glaciation in the Cromer Till. But where in these sections 

 shall we find above the Cromer Till a horizon to correspond with this 

 of the Buried Cliff? Certainly not in the so-called Middle Glacial 

 (which I believe to be closely analogous to the Intermediate ISeries 

 of Yorkshire), whose accumulation must have taken place under 

 conditions altogether different ; and at any higher level there is 

 nothing in the slightest degree comparable. 



* Geol. Survey Mem. ' Holderness,' p. 65. 



t Geol. Survey Mem. ' East Lincohisiure/ p. 78 ; and A. J. Jukes- Browne, 

 Quart. Jouru. Geol. Soc. vol. xU. (1885) p. 110. 



