SOUTH LANCASHIKE, CHESHIRE, AND THE WELSH BOEDER. 377 



the direction has been determined by that of the valleys in which 

 they occur, while those which run straight down the slope on the 

 Ormes Head are probably due to the local action of gravitation. 

 Omitting these doubtful cases, it will be seen that along the east 

 border of Wales there is a very marked parallelism among the striae 

 in a general east-north-east direction. Out of the whole number 

 observed in this part of the district, five only occur in that quarter 

 of the compass in which the Liverpool striae are so thickly grouped, 

 those, namely, of Talargoch, Gwaenysgor, Penmaeu, Hope Mountain, 

 and Hawarden ; and all these occur on the outskirts of the Welsh 

 drift-area. The remainder, as I shall presently show, agree in di- 

 rection with the drift-transportal of the area in which they are situ- 

 ated. The horizontal striae of the Great Ormes Head, though ap- 

 proximately parallel to these, belong more probably to the Anglesey 

 system of glaciation, and were produced by ice from the north. 

 Those of Llandulas are more doubtful : from their contiguity and 

 parallelism they were probably produced by the same agent ; but 

 situated, as they are, close to the boundary, and agreeing in direction 

 more or less with both the Mintshire and the Anglesey systems, it is 

 difficult to assign them to either with any degree of certainty. 



This change in the direction of the striae which takes place on 

 crossing the Welsh border is accompanied, as before stated, by a 

 corresponding change in the nature of the drift, the general arrange- 

 ment of the beds remaining the same, but the materials showing 

 clearly a transportation from the west and south-west. The boundary 

 of the Cheshire and Lancashire type of drift with its northern 

 derivatives is shown on the accompanying map (p. 370). It runs 

 from the Menai Straits by Llandulas to the Yale of Clwyd, nearly 

 coinciding with the coast, but bending southwards so as to include 

 rhe low ground bordering the coasts at the Ormes Head, Colwyn 

 Bay, and Llandulas, and the northern part of the Yale of Clwyd. 

 Rounding Cwm Mountain, the northernmost point of the Moel 

 Eammau range of Silurian rocks, the boundary then bends sharply 

 up the narrow valley occupied by the Dyserth stream, so as to in- 

 clude a portion of the high ground formed by the Carboniferous 

 Limestone. Northwards it once more follows the hill-foot by Talar- 

 goch and Prestatyn, to Grouant, whence bending southwards it runs 

 through Flintshire, rising in places to some of the high ground 

 formed by the Carboniferous-Limestone escarpment. West of 

 Chester also, the rise from the plain to the hills being gradual, the 

 boundary runs up to a comparatively high level, so as to pass 

 within a mile of Hope Mountain. Thence it doubles back to Eossett, 

 and so once more southward. 



Along portions of this line the northern drift is banked up 

 against a steep inland cliff as at the Ormes Head, Llandulas, 

 Talargoch, and Prestatyn, this cliff being, in all probability, a pre- 

 glacial coast-line. In such situations the northern drift is found 

 to overlie the drift of local origin, presenting in its comparatively 

 stoneless homogeneous condition a strong contrast to the intensely 

 stony local deposits. In other places, as at Bossett, the northern 



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