404 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 6, 



sequently the sandstones at Tunbridge Wells would be the equiva- 

 lents in greater development of those at Quarry Hill. The organic 

 remains, although not numerous, tend to confirm this view, as the 

 Unio Gaulteri and Unio antiquus are the characteristic fossils in 

 the upper beds at both localities. 



The sections described above traverse one of the principal longi- 

 tudinal lines of disturbance of the Weald, the effects of which have 

 been clearly pointed out by Mr. Hopkins in his interesting paper* 

 " On the Structure of the Wealden District." He describes it as 

 extending through Bidborough and Brenchley Hills, showing at 

 both these places distinct evidence of an anticlinal ridge varying in 

 importance. 



At the point where the railway intersects the plane of disturbance, 

 the anticlinal ridge has been removed by denudation, causing the 

 remaining strata to present phaenomena of rather complex character. 

 The dotted line in the section shows the probable position of the an- 

 ticlinal line, one of the lateral effects of which is exhibited in the 

 fault at the Quarry Hill section. On the south side of the ridge 

 there is also evidence of a probable lateral fracture in the vicinity 

 of the Powder Mills valley, as evinced by the change of level of the 

 lower clays (E) to which we have before referred, and by other facts 

 observable in some of the adjacent quarries on the slope of the hill 

 on the north side of the Powder Mill valley, in one of which is a 

 succession of numerous small faults rising southward. This in 

 general is an indication of the proximity of some larger fault or 

 faults in the same direction. In the same plane as these changes, 

 and with the same parallelism to the Bidborough anticlinal, are the 

 disturbances described by Mr. Hopkins at Nashes, a point a few 

 miles westward of the above locality. 



We have therefore the effects of a movement of relative elevation 

 venting itself in an anticlinal ridge flanked by parallel fractures of 

 depression, thus : 



Fig. 5. 



a system of structure not perfectly satisfactory to our minds ; but 

 after a careful study and examination of the question, we are induced 

 to offer it as a possible solution to the stratigraphical difficulties of 

 the problem, and as being, as well as we could ascertain, in accord- 

 ance with the observed phaenomena. 



* Geol. Trans, vol. vii. p. 12. 



