HiNCH. — The Eskers of Ireland. 



139 



acceptance means that the principles and methods adopted 

 in the investigation into glacial and late glacial deposits 

 during the past generation will have to be abandoned, and 

 a great deal of the work already accomplished by the 

 Geological Survey of Ireland and other workers must be 

 regarded as obsolete if this return to antique views is agreed 

 to. Ui;ider these circumstances the evidence of submergence 

 which Prof. Gregory proposes to rely upon will have to 

 bear the strictest investigation as to its accuracy and as to 

 its bearing on the immediate point under discussion. 



It may be said at once that no such submergence can be 

 imagined with our present knowledge of the surface deposits 

 of Ireland, and that much of the evidence brought forward 

 by Prof. Gregory has long been regarded by Irish geologists 

 as proof that the districts in which they are found had been 

 traversed by the ice sheets which deposited the marine 

 shells in their present position. Most of the evidence 

 produced by Prof. Gregory was collected before the true 

 nature of the glacial deposits was understood, and some of 

 it is merely inaccurate interpretation of the facts observed 

 in the field, such as the confusion of attributing the kitchen- 

 midden deposits of Tarmon Hill in the Mullet to a recent 

 marine submergence. It is to be regretted that Prof. 

 Gregory has not seen fit to examine any of the modern 

 work done in glacial geology in Ireland, or if he has examined 

 it, that he has ignored it so pointedly. 



It can be stated with confidence that there are five areas 

 in Ireland where marine shells and shell fragments have 

 been found in abundance or in sufficient numbers to remove 

 any doubt on the subject, in both the boulder clay and the 

 overlying sands and gravels— Clare Island, North Mayo, 

 Antrim and Down, the Counties of Louth, Meath, and 

 Dublin ; and Wexford, Waterford and Cork. As the shelly 

 drifts of Mayo, north-east Ulster, and south-east Leinster 

 have no direct bearing on the proposed postglacial sub- 

 mergence of the central plain we need not examine them at 

 great length ; they represent in each case the advance inland 

 of an ice sheet which has crossed an inlet or strait of the sea 

 either from the adjoining mainland or from another country, 

 and the shelly deposits laid down are in all cases definitely 

 limited in extent and do not point to submergence. 



A 2 



