322 Geological Society : — Mr. Hopkins on the 



author lines of flexure. The central portion of the district is first 

 described. The following lines of elevation are found in it. 



1. Hastings Line. — This line runs to the north-east of Hastings 

 towards Battle. It has been mentioned by Dr. Fitton and other geo- 

 logists. The author had not had time to examine it himself. 



2. Brightling Line. — This is strongly anticlinal, and runs along 

 the high ridge of Brightling Down as far as Heathfield Park, where 

 its distinct features are lost. The author has not ascertained whether 

 it is a continuation of the Hastings line. 



3. Wadhurst Line. — This line runs by Wadhurst and Hawks- 

 hurst, to the south-west of which place it is lost. It also ranges 

 westerly along the ridge between Wadhurst and Mark Cross. 



4. Crowborough Line. — Crowborough Beacon stands on what must 

 be regarded as the great central ridge of the district. The anticlinal 

 line runs near the Beacon and is continued westerly to the north 

 of Balcombe. No traces of it however are distinguishable beyond 

 Horsham. 



5. Cuckfield Line. — This line extends parallel to that last described, 

 and immediately to the north of Cuckfield. It is not to be traced far to 

 the west of that place. To the east it is continued across the Brighton 

 railway, where it was very distinctly exhibited in the new cuttings. 



6. Frant Line. — At Lamberhurst this line is distinctly marked. 

 It proceeds westward along Frant Hill, where its evidence, however, 

 is not very distinct. It appears to be lost entirely not far to the west 

 of Frant. 



7. Bidborough and Brenchley Line. — Bidborough Hill is formed by 

 a strong flexure of the beds by which the Hastings sand is brought 

 up from beneath the Weald clay. Brenchley Hill is formed in the 

 same manner, but presents a more distinct anticlinal arrangement. 

 These hills are separated by a wide transverse valley of denudation, 

 but there can be little doubt, it is conceived, that they belong to the 

 same line of elevation. The dislocation is also continued westward, 

 but with less distinctness, across the Medway. 



All these lines preserve a remarkable parallelism with each other 

 and with the curved central axis of the district. 



The author also describes several transverse valleys of the central 

 portion of the district, and states the evidence on which he believes 

 them to have originated in transverse dislocations. 



8. Greenhurst Line. — This line has been described by Mr. Martin, 

 by whom it was first detected. It is distinctly marked from a 

 point south-west of Pulborough, whence it runs not far from and 

 parallel to the chalk escarpment, till it strikes into the chalk at 

 Piecomb. Its continuation westward is not very distinct, but east- 

 ward it is strongly defined at Lewes. Several remarkable transverse 

 valleys across the greensand ridge are also found in the south- 

 western part of the district, and present evidence of having originated 

 in transverse dislocations. Their directions are as nearly as possible 

 perpendicular to that of the Greenhurst line. 



9. Line from Farnham to Seven Oaks. — This line runs parallel to 

 the chalk escarpment of the North Downs and near to it. It is a 



