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militate against the idea of their formation resulting from the 

 action of springs and slips. There is not, however, any difficulty 

 in explaining the seeming anomaly. Although the combes are 

 now dry, such was not always their condition. The Fullers 

 Earth, which now occupies an irregular position behind the 

 escarpment of the Cotteswold range, — its distance backwards 

 from the escarpment varying from a quarter of a mile at BirdHp 

 to three miles at Minchinhampton, two miles at Painswick, 

 fifty yards at the Brick -pits near Stanley Wood, and to about 

 a hundred yards at Frocester Hill, — was once continuous over 

 the whole district comprised in the area between its northern 

 and southern hmits; the water was then everywhere thrown 

 off in springs from its surface; it ran down the slopes, and 

 assisted in deepening the valleys, and excavating the combes. 

 As the Fullers Earth, however, was gradually denuded, the 

 springs proportionately diminished, until at last they disappeared 

 entirely. In consequence, the rainfall, instead of being thrown 

 off as before, now sinks into the Inferior Oolite, and where the 

 valleys are sufficiently deep, is thrown out in new springs at the 

 junction of the Sands with the Upper Lias ; but from their more 

 recent origin, these springs have not as yet formed deep channels. 

 In some valleys the cessation of the flow of the springs over the 

 escarpments of the Inferior Oolite is quite recent. An instance 

 of the kind occurs on the south-west side of Swift's Hill, near 

 Stroud, where the springs, which flow from the Fullers Earth, 

 and which apparently down to within a comparatively recent 

 date ran over the escarpment of the Inferior Oolite, have, from 

 the causes I have mentioned, ceased to do so, and the water now 

 passes into the beds of the Inferior Oolite, is thrown out at the 

 base of the Sands by the Upper Lias, and forms a new spring 

 near the bottom of the hill. At the head of the combe a 

 water-trough, which the spring once supplied, is still to be 

 seen in its original position. Other instances are by no means 

 rare in the hne of the western edge of the Fullers Earth. 



Dry valleys are sometimes formed by surface drainage alone, 

 and the undulations upon the table land of the Cotteswolds 

 may be referred to this cause ; but where the slopes are formed 



