Chari,esworth — Glacial Geology oj North- West of Ireland. 265 



One of the most magnificent of these morainie features extends from Six 

 Mile Cross to Pomeroy, the latter village being built upon it. It is of 

 considerable width and is gashed by the river running down from Crooked 

 Bridge. Oarvill Lewis was over this ground, and with his usual perspicacity 

 recognized its niorainic character. He writes : — ^ 



" Huge drift hills, the largest I have ever seen, lie between Pomeroy 

 and Carrickmore, piled up some. 400 feet high. They are stratified and 

 unstratified drift. Fine exposures. Enormous accumulation. They are 

 part of a great moraine (?) 300 feet high, and are covered with large 

 boulders. It seems to be a terminal moraine. Several lakes are in the 

 moraine." 



In a foot-note is added : — 



" This is probably a moraine made at the melting of two glaciers, one 

 an Irish, and the other a Scotch one; one going north, the other south, 

 perhaps (1886)." 



Though correctly discerning their morainie origin, he was at fault in 

 ascribing them to the action of two ice-sheets; a correct interpretation could, 

 however, only be obtained from a careful examination of the adjacent reo-ions. 

 To the south of this billowy belt and along its foot extends a large valley — 

 the " Pomeroy overflow " — greatly exceeding iu depth 100 feet, and followed 

 for some miles by the line of the G.N.E.I. It is now occupied by a small 

 stream totally inadequate iu size to excavate the valley. "Where its sides are of 

 drift, the valley is extremely wide and deep, exposing the moraines in many 

 beautiful sections," becoming constricted, however, where it breaches the 

 " solid." As judged by its location and size, it is evidently the channel which 

 carried off not only the drainage from the hill-slopes to the west but also 

 the great flood-waters pouring off the melting ice-front standing on the line 

 of the moraine to the east. Its width and depth are commensurate with 

 the height and breadth of the morainie accumulation, both indicating by their 

 dimensions a prolonged halt on this line. Many other moraines in the 

 vicinity are gigantic and enclose lakes. Of one of these accumulations 

 Carvill Lewis wrote : — ' 



" Immense kames are about Lough Cam, the largest I have seen. 

 Lough 0am is enclosed in a series of ridges." 



1 Op. cit., p. 115. Portlook refera to this moraiue as "the masses of detritus near 

 Pomeroy." (Report, p. 639.) 



^ These are well seen from the Great Northern Bailway. At Pomeroy itself, the drift 

 is seen to consist of shites (L. Palaeozoic), large and small boulders of pyroxenicrock and 

 granite. No flints rewarded a careful search. This composition is clearly indicative of 

 ice ti-ansport from the west, 



'Ibid., p. 115. 



