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time to allude to the Palaeontology of the rocks in" the Deighbourhood of 

 Bmlih, further than to observe that the fossils of the lowest stratified 

 deposits of the district u.form us that the oldest strata here belong to the 

 age of the Upper Llandeilo beds, of which the well known Trilobites Oyygia 

 Buchn and Amphun tyrannus are characteristic fossils. 



There is one point to which, however, in conclusion, I should like to ask 

 the attention of loc.U geologists. The drifts and gravel deposits of this neigh- 

 bourhood are particularly worthy of attention. There are in the fi.st place 

 high upon the summit of the hilly platform, manne drifts, which were no 

 doubt deposited when the whole of this country, like the greater part of 

 Europe, was submerged beneath the waters of the glacial seas. There are 

 also ancient river drifts, which are the result of an ancient Wye which flowed 

 at a level far higher than the existing river, and which, fed by winter ice and 

 snow, which filled every vale and covered every hill, swept down under each 

 summer's sun as a torrential and rock-bearing stream. There are atmospheric 

 drifts, by which I mean those local deposits which are the result not only of 

 the exiting atmospheric influences of rain, and frosts, and snows, but the 

 deposits of the later part of the glacial epoch, which affected this country ages 

 ; after the emergence of the land from beneath the gh.cial seas, and when its 

 physical contour was much the same as at the present moment. The cbmatial 

 adaptations were, however, far colder. Glaciers swept down from the higher 

 hUIs through the hill vuUeys, and winter snows and ice filled each vale and 

 hoUow. The result of this history was the movement of large masses of rocks 

 and drifts down the hiU slopes, and the transportation of those masses for 

 long distances along the hill faces and along the vales of the district to which 

 they belong. 



One characteristic, however, marks such travelled masses. They are 

 alway. local, that is to say they never cross a valley or are transported over 

 a h,ll platform. Thpy are generally angular masses, or only rubbed on one side 

 These drifts are the results not of marine agency, or of glaciers, as is gene- 

 rally understood of glacier transportation of rocks, but of perennial snow and 

 ice which once sheeted over the greater part of England all the autumn and 

 winter months, but has now, happily, disappeared under a more genial climate 

 and warmer temperature. 



Much has been said and written lately about the evidence of the action 

 of the sea among these beautiful hills of Wales. Believe me, as an old student 

 of these phenomena, when I say that there is no greater mistake than to 

 attribute the principal drift phenomena you see in this country to the action 

 of the sea. The drifts of this district are, with /ery few exceptions, old river 

 and atmospheric drifts. 



