2 MR. R. D. DARBISHIRE ON GREAT-ORME^S-HEAD 



present day, it is perhaps not wonderful if it is particularly 

 in this field that, by the side of the more eminent scientific 

 students, many less-qualified observers should offer their 

 contributions to the better knowledge of our own country 

 or of special districts of it. 



If I venture to occupy the attention of the Society with 

 the following notes, it is because circumstances and local 

 convenience have enabled me for some years past to make 

 frequent visits to the Great Orme's Head, and because I 

 think that a certain familiarity with, and a definite study 

 of, modern sea-beaches and sea-beds, their forms and in- 

 habitants, and the preservation and disintegration of their 

 peculiar remains enables me to off'er some special illustra- 

 tions of its peculiar recent history. 



It will be convenient to preface what I have to say by 

 a short summary of observations already recorded. Pro- 

 fessor Ramsay (Quart. Journ. Geol. Soc. viii., 1852, and 

 again in ^ Old Glaciers of Switzerland and N. Wales,^ 1 860) , 

 after discussing the superficial appearances of Caernarvon- 

 shire and Anglesey, states, as a well-ascertained fact, that 

 previously to the Tertiary Glacial epoch the grander contours 

 of hill and valley were nearly the same as now. Much of 

 the land was then slowly depressed beneath the sea ; and 

 icebergs drifting from the north, and pack-ice on the shores, 

 ground along the coasts and sea- bottoms, smoothing and 

 striating the surfaces over which they passed in contact, 

 and, in the course of ages, depositing clay, gravel, and 

 boulders over wide areas that had once been land. The 

 grooves and striations on ice- smoothed rocks still bear wit- 

 ness to the general southward course of the ocean-currents 

 of those icy seas. The true glacial drift Mr. Ramsay traces 

 to a height of about 2300 feet on some of the Caernarvon- 

 shire mountains. The land then slowly rose at least this 

 height above the sea-level ; and during this long period, 

 while the sea was rearranging and rewearing the deposits 



