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PKOF. T. M'EENNY HUGHES ON THE 



and there in the Wheeler valley. There is nothing in the sections 

 below the Mount or at Brynelwy at all resembling it. It is not 

 like the drift of Wigfair Isaf or the variable deposits of Wigfair 

 Uchaf, except in each case the obvious top few feet of rainwash. 

 It is like the mixed mud and sand and gravel which we find every- 

 where overlying the St. Asaph Drift, crumbling down the hill- 

 sides and conforming to the slope of the ground. There is no 

 sorting of the material, as we should expect if currents ran along 

 the rock-face or waves dashed against it ; but there is, here and 

 there, an obscure and gentle false-bedding from the cliff as of 

 rainwash creeping down the slope. 



All over the slope above Ffynnon Beuno the superficial deposits 

 are creeping down the hill -sides, hanging on every ledge and 

 catching on every obstacle. Any old fence proves how rapidly this 

 process is going on ; one such fence ran across the bottom of the 

 field in which the northern end of the cave comes out, passing up 

 to the edge of the precipice, about 16 feet from where the drift fell 

 into the cave. 



There we see (fig. 5, from a photograph by Mr. A. D. Walker) 

 that the " head," or travelling talus, has been banked up on the 

 upper side of the hedge, so that there is a fall of some 8 feet from 

 the field on the upper side of the fence to the natural level below it, 

 which also has been lowered by the general working of the soil 

 down the slope. In the sketch the stack of sods lies on the top of 

 this old fence ; the tree grows out of the side of it. This super- 

 ficial talus is the upper part of what has been dug through at 

 the upper mouth of the cave, beyond the two persons standing by 

 the rails, yet it has not been distinguished as different from that 

 which has by some been taken as part of the main mass of the 

 drift ; and rightly so, I think. It is all a remanie material. 



If, after an inspection of the ground, any doubt remained as to 

 the recent age of some, at any rate, of the material which covered the 

 northern mouth of the cave, and which has been by some all 

 equally referred to glacial drift, a more careful inspection of the 

 glaciated stones out of the mass should dispel it. There were 

 plenty of glaciated stones, such as may be found everywhere along 

 the flank of the hill ; but some of these, in addition to the more or 

 less well-preserved glacial strise, carried the deep, rough, irregular 

 grooves of agricultural implements. The tilled soil and the rain- 

 wash rapidly accumulate on ledges and against fences on the steep 

 slopes of the Clwydian range. Similar terraces may be seen close 

 by in the second and third field above the road east of Brynbella. 



The absence of shells in any of these deposits, so far as negative 

 evidence is of any value, may be explained on the supposition that the 

 beds have been much modified, if not transported some distance down 

 hill, by subaerial action. Fragments of shells are found not uncom- 

 monly in the St. Asaph Drift, along the rivers Clwyd and Elwy, 

 but not in the deposits about the Ffynnon Beuno caves. Moreover, 

 the surface of the limestone fragments was decomposed in the 

 drift outside the cave, leaving the less soluble bands sticking out 



