12 MR. K. D. DARBISHIRE ON GREAT-ORME^S-HEAD 



I have not been able to satisfy myself of the existence 

 of this bed elsewhere than at the side of the Gwydfyd 

 valley, not far from the Bath-house, undisturbed; but 

 the occurrence of travelled boulders and pebbles in sub- 

 aerial beds, to be described presently, records its former 

 existence at even higher levels than that just named. 

 Thus, a single boulder of greenstone was found amongst 

 angular fragments of limestone, talus, and superficial clay 

 above Gwydfyd farm, at 380 feet above the sea. 



The foregoing deposits are those of sea-bottom, — the 

 boulder-clay telling unmistakeably, in its great rounded or 

 angular stones, of the beach-gravel carried along by the 

 travelling ice of the drift ocean, or the debris of the glaciers 

 of the rising land, lodged in the depths of a more or less 

 profound sea. The beds have probably successively suf- 

 fered great vertical denudation during the process of eleva- 

 tion, and they are still subject to considerable horizontal 

 waste from the west. The beach is covered with great 

 boulders of greenstone, granite, slate, and other rocks, 

 polished and sometimes scratched. The same boulder-clay 

 appears in the shore cliff at the west end of Little Orme^s 

 Head, If I may offer a conjecture as to the period of the 

 deposit of the upper or boulder-clay beds, I would say that it 

 took place towards the close of the Glacial epoch, and was 

 due to the redistribution of the more ancient northern drift, 

 the remains of which it now covers, under the influence 

 of the elevation and of the descent of glaciers from Snow- 

 donia (in whose recesses the Astarte has been found on 

 beaches), very long after the vicissitudes of the earlier period 

 had removed much of the superincumbent rock (ah-eady 

 shaped by rain and frost before its first submergence) and 

 had left a rocky sea-bottom filled up with Glacial clays and 

 at the time rising and, though still under water, shaped 

 much as we now see it. 



I will presently give reasons for thinking that the actual 



