84 SECTIONAL ADDRESSES 



as eating it ; Sir Arthur cannot both adopt the Alpine succession and 

 abandon one member of the sequence because it does not accord. Satis- 

 factory correlation will doubtless be possible in course of time, but it 

 must needs await fresh investigation of the successions of the Rhine 

 Valley and Low Countries and of the river-deposits of France, which 

 may be regarded as connecting-links between the deposits of the Alpine 

 area and those of eastern and southern England. 



The mention of southern England reminds me that within the limits 

 of this address I have been unable to deal, even briefly, with the evidence 

 of changes of level of the land and sea, and the consequent erosion and 

 aggradation of the river-systems of Britain. In the area south of the 

 river Thames glacial deposits as such (that is, as distinguished from 

 deposits due to snow-sludge or movement of semi-frozen superficial 

 material) are absent. Correlation must be effected, therefore, with 

 river-terraces and raised beaches, and will depend on evidence of changes 

 of level, combined with that of included implements. Information 

 comes but slowly to hand, and the problems are exceptionally difficult. 

 Two facts emerge : (i) the widespread submergence and aggradation 

 of river-valleys in Acheulian times, and (2) the marked elevation and 

 river-erosion of Mousterian times. The movements in southern and 

 eastern England appear to have been differential, possibly of the isostatic 

 type, rather than eustatic uplifts like those in the Mediterranean area 

 described by Lamothe, Deperet, Gignoux and others. Nevertheless, 

 the work that has been accomplished, notably by Prof. L. 8. Palmer, 

 is promising of fruitful results. While leaving open the question of 

 correlating changes of level throughout Britain, I have therefore attached 

 his sequence to the table accompanying this address. 



Any attempt to measure the antiquity of Man in Britain in terms of 

 years is bound to be speculative and unscientific so far as the geological 

 evidence is concerned. No deposits similar to the van^e-clays of Sweden 

 have yet been found in Britain. From the varvx-clays of Sweden, as 

 is well known, G. de Geer and other workers have concluded that about 

 13,500 years have elapsed since the receding front of the ice occupied 

 a position in southern Scania. Using this as a basis, he dates the com- 

 mencement of the Gothi-glacial sub-epoch of the last glaciation (? Mag- 

 dalenian) as from 15,000 to 16,000 years ago. Possibly the earlier sub- 

 epoch (Dani-glacial) may also be dated, but any extrapolation of the 

 time-scale in years to glacial episodes before the latest (the maximum 

 of which was marked by the Baltic moraine) is, as de Geer and Sollas 

 have emphasised, to add to ' a hecatomb of erroneous dates.' 



In the foregoing review of our knowledge of British glacial deposits 

 and their relationship to human industries, I have been compelled to 

 summarise the work of a large number of investigators, many of whom 

 I have been unable to mention by name. For this omission I crave 

 pardon, and also for possibly misrepresenting their views in attempting to 

 secure brevity, particularly when qualification of a bald statement would 

 have been desirable. It may be that more agreement emerges from 

 the foregoing suggested classification than might at first have been ex- 

 pected, but it is certain that the facile correlations so often made, although 



