406 H. W. Monckton — Marine and Siibaerial Erosion, 



in the railway cutting just west of Enthorpe Station, near Market 

 Weighton. The overlying chalk was softer with flint nodules, and 

 here and there a tabular layer. 



A small quarry at the turning of the lane to Goodmanham Lodge 

 Farm showed three layers of tabular flint. Holaster planus was 

 common in the Chalk. The position of this quarry is just beyond 

 a cutting (now grassed over) in the railway west of Kipling Cotes 

 Station, where Mr. Allen, collector for the Geological Survey, found 

 Micrasters now referred to as Micraster prcecursor. The horizon of 

 the quarry is a little lower than the cutting. 



The Chalk in Yorkshire containing layers of flint has been noticed 

 by Professor Blake, who, unable to agree with the divisions of 

 Barrois, formulated a classification based on the characters of the 

 flints.^ He gives a thickness of 50 feet to " Chalk with tabular flint," 

 and calls it the barren zone. This "Chalk with tabular flint" is 

 undoubtedly the continuation of that of Lincolnshire, and we may 

 take it as being roughly the equivalent of the nodular Chalk of the 

 south-east of Eng^land and of the Chalk Rock of the Midland counties. 



VII. — On some Examples of Makine and Subaerial Erosion. 

 By Horace "Woollaston Monckton, F.L.S., F.G.S. 



ON the excursion of the Geologists Association to Gower last 

 Easter our Director, Mr. E. H. Tiddeman, showed us a series 

 of examples of the celebrated raised beach, and a good deal of dis- 

 cussion arose as to its relation to the other recent deposits of the 

 district. Into those questions I do not propose to enter on this 

 occasion, but will accept, what all admitted, viz., that the beach 

 is an old sea beach, that the platform upon which it rests is the 

 work of the waves, and that it has been raised to its present position 

 by earth-movement. 



The platform is formed of solid rock. Carboniferous limestone, 

 which for the most part dips at a very high angle, so that the old 

 beach rests upon the upturned edges of the strata. We were shown 

 one particularly interesting example between Caswell Bay and 

 Brandy Cove ; there the rock platform is some 20 feet above the 

 present beach. 



Its top is fairly level, but a transverse section would probably 

 show a dip seawards. The old beach has become consolidated into 

 a calcareous breccia, and rests on the platform, which has been some- 

 what eroded in places, so tbat in one place the beach projects beyond 

 it. Close by, Mr. Tiddeman drew our attention to a rounded knob 

 of rock rising a few feet above the platform, which had no doubt 

 stood out above the shore and projected through the old beach. The 

 irregularities of the platform under the beach are no doubt largely 

 due to the fact that it is limestone and subject to decay underground. 

 In one locality on the coast to the left of the estuary near Penard 

 Castle our Director showed us a place where the platform is overlain 

 by, and consequently protected by, a considerable thickness of beach 



1 " On the Chalk of Yorkshire" : Proc. Geol. Assoc, 1878, vol. v, p. 232. 



