6ie REPORT— 1894. 



•J From the Edge Hill escarpment a fork of the Horton vale runs alongside 

 Adsum Plantation, and makes what is knowJi as Adsum Hollow. The terraces 

 sweep in regular curves along the high banks of the stream, and where it joins the 

 main vale to the North of Horley the steps are so prominent as to give the name 

 of Steps Meadow to the ground. Grtdenton Hill, on the Burton Darrett range, is 

 very regularly and beautifully terraced on three sides. 



. The author does not attempt description of the chalk hills or the lynchets of 

 Dorsetshire. The sandy marls of the Dorsetshire Inferior Oolite have a composi- 

 tion approaching that of the micaceous marls of the Midlands, and reasons like 

 those brought forward will no doubt prove their similar mode of formation. 



, The Probable Range of the Coal-Measures under the Newer Rocks of 

 Oxfordshire and the Adjoining Counties. By Professor Boyd 

 Dawkins, F.R.S. 



The principle laid down by Godwin-Austen and Prestwich that the master 

 or tectonic folds in the pre-Carboniferous and Carboniferous rocks are lines of 

 weakness along which the newer rocks have been folded in later times, has been 

 recently applied by Bertrand to the district of northern France. In the present 

 communication the author proposes to see how far it can be used in the search 

 after the buried coal-fields of the counties of O.xford, Buckingham, Berks, and 

 Wilts. 



From the relation existing between the tectonic anticlines and synclines in the 

 districts of South Wales, Gloucester, and the West of England, where they can 

 be studied at the surface in the Palteozoic rocks, most important conclusions may 

 be drawn as to the coal-fields buried under the newer rocks in southern England, 

 They are as follows : — 



1. The Mid-Devon syncline, traceable eastwards until it cuts the sea-line near 

 Bognor. 



2. The North Devon anticline, which runs eastwards through the Vale of 

 Wardour, past Salisbury, and along the anticline of the Weald from Petersheld 

 to Dungeness. 



3. The Mid-Somerset syncline, which sweeps eastwards through the Vale of 

 Bridgewater and Glastonbury, through the chalk downs between Heytesbury and 

 Hindon, to Haslemere. From this point it is continued to the east through 

 Tunbridge Wells and Tenterden to the sea to the south of Hythe. 



These three folds have no bearing on the range of the coal-fields in the drainage 

 area of the Thames. The fourth, or Pembroke-Mendip anticline, and tlie tifih, 

 or South Welsh syncline, are the two great tectonic folds which remain for 

 consideration. 



The Pembroke-Mendip anticlinal range, highly faulted and folded, is traceable 

 westwards into South Ireland, and eastwards, through Pembroke and the peninsula 

 of Gower, to the south of Cardifl', through Weston-super-Mare and the Mendip 

 Hills. Throughout this area it forms the southern margin of the coal-fields. 

 Near Frome it plunges beneath the Oolites. It is, however, clearly marked by 

 the Upper Greensand anticline of the Vale of Pewsey, and by the Upper Green- 

 sand inliers of Ham and Kiugsclere. Thence it passes along the line to the 

 high downs past Basingstoke and Faruham to Peasemarsh, south of Guildford, 

 where it is seen in an inlier of Weald clay. It is carried still further to the east 

 by similar inliers south of Westerham, and at Wateringbury and Maidstone. 

 From Maidstone it sweeps to the south-east, through Otham and Ashford, 

 arriving at the coast close to Hythe. In the eastern portion of its course it has, 

 in my opinion, been the chief factor causing the south-eastern trend of the North 

 Downs in the district of Maidstone. It forms also the southern boundary of the 

 South-eastern coal-field discovered in the boring at Dover, and of the coal-fields of 

 northern France and Belgium. 



The South Welsh syncline, only two miles wide at St. Bride's Bay, in the 

 anthracite district of Pembroke, widens out into the coal-field of South Wales, 



