X02 



T. MELLARD EEADE ON THE 



14. The Drift-deposits of CoLwrN Bat. By T. Mellard Reade, 

 Esq., C.E., P.G.S. (Eead January 14, 1885.) 



In a former paper* I gave a short sketch, of the drift disclosed in 

 the baliast-pit at Colwyn-Bay station ;' and as in Pebruary of 1884. 

 I had an opportunity of extending my observations over a larger 

 area, I now propose to give an account of them. 



From Colwyn Head to Ehos Point is a distance of about three 

 miles; and all along the shore, except where obscured by the Colwyn- 

 Bay parade or grassed over by the railway company, are to be seen 

 in cliffs excellent sections of the drift. 



This drift, extending backward to the foot of the hills which 

 sweep in a curve from headland to headland, rests nearly wholly on 

 the Silurian rocks, representatives of the Wenlock Shale. 



Colwyn Head or Penmaen Cliffs, and Bhos Point, are denuded 

 remnants of the Carboniferous Limestone, and near to each of these 

 headlands the drift is seen to rest directly on the limestone, there 

 being no exposure of the underlying Silurians anywhere to be seen 

 in Colwyn Bay. 



Pig. 1. — Section just beyond the Cottage west of the Colwyn-Bay Hotel. 



1. Grey Till, packed fiill of stones, partly Silurian Slate and Grits, and Carbo- 



niferous Limestone. 



2. Cream-coloured Till. 3. Sand. 4. Brown Boulder-clay. 5. Soil. 



The surface of the drift is remarkably level, excepting where it 

 gradually creeps up the hills. Most of the houses in Colwyn Bay 

 are built upon it. It is crescent-shaped on plan, thinning out to- 



* Drift of N.W. of England and N. Wales, part ii. Quart. Journ. Geol. So8. 

 vol. xxxix. p. 111. 



