19 18. HiNCH. — The Irish Sea Glacier. 55 



ice-sheet passed from north-west to south-cast over the 

 higher land of the island, laying down the boulder-clay and 

 gravels, which have yielded typical northern erratics and 

 many important arctic shells and remains of other animals. 

 The Geological Survey Memoir on the Geology of the Isle of 

 Man, which was written by Lamplugh and published in 

 1903, has had great influence on research in glacial geology 

 in the Irish Sea area, challenging as it did, the accepted 

 theory of an interglacial submergence, and stimulating 

 extended work in the field on the subject. 



Turning from the Isle of Man to the eastern coast of 

 Ireland, deposits of the Irish Sea Glacier have been found 

 by the writer at various points south of Dundalk. At 

 Glaspistol, south of Clogher Head, in Louth, there occurs 

 in the floor of the present beach a patch of boulder-clay 

 containing northern erratics and shells. South of the Boyne, 

 at Benhead, where the cliffs are formed of boulder-clay, 

 similar erratics and shells have been found by the writer 

 and inland north of Gormanstown, gravels with erratics 

 and shells, w^ere discovered by W. B. Bruce, to whom the 

 writer is indebted for the report. During the Natural 

 History Survey of Lambay, Prof. Seymour, who acted as 

 geological director, found that the Irish Sea Glacier had 

 overridden the island, laying down boulder-clay containing 

 northern erratics, and in the boulder-clay at Saltpan Bay, 

 on the northern shore of the island, a number of shell- 

 fragments were found by the writer.^ On the mainland 

 at Skerries shell-fragments and erratics are reported from 

 the sands and gravels near the railway station, while at 

 Corballis, on the southern shore of Portrane promontory, 

 shell-fragments have been obtained by the writer from the 

 boulder-clay. 



The district in the middle of which the city of Dublin 

 stands was the first area surveyed by the Geological Survey 

 for the new Drift maps, and from many localities in this 

 area arctic shells and northern erratics have been obtained." 



1 H. J. Seymour, " Geology [of Lambay]," Irish Naturalist, vol. xvi., 



PP- 3-13 (1907). 



^ Geological Survey Memoir, Geology of Dublin, 1903. 



A 2 



