'226 Messrs. Bucrland's and Conybeare's Observations on the 



scenes are exhibited amonj^ the Mendip hills, than in the narrow dingles 

 extending from Mells to Vallis-house, and along the three streams which flow 

 northwards into the Mells river from the villages of Nunney, East Cranmore 

 and Leigh. The dip presented in these sections shows uniformly that the 

 hmestone-strata mantle round the eastern extremity of the axis of old red sand- 

 stone, being inchned usually at an angle of about 45°, but occasionally being 

 nearly vertical. 



Towards the heads of the valleys just described, and at the distance of about 

 6 miles from where the inclined strata first appear, at the village of Little Elm, 

 the Mendip range begins to assume the character of a chain of hills. Here 

 also, in Railford Bottom, the first or easternmost nucleus of old red sandstone 

 commences. This nucleus, running east and west, at first constitutes a narrow 

 ridge of very inconsiderable elevation ; but it increases both in breadth and 

 height on passingthe village of Downhead [PL XXXILfig. 1 .and fig. LA], and 

 within 3 miles west of this point forms the bold and conspicuous ridge, the east- 

 ern extremity of which is called Beacon-hill. The western extremity is re- 

 markable for the strong entrenchment of Masberry Castle*, a lofty eminence 

 999 feet above the sea, commanding an extensive view of the surrounding coun- 

 try, and one of the stations on the Ordnance survey. [PI. XXXIL fig. L B.] 

 This ridge, like most of the other heights of the Mendip chain, is covered with 

 ancient sepulchral barrows. To the west of Masberry Castle the ground sud- 

 denly falls, and the old red sandstone becomes hidden under a mantle of moun- 

 tain limestone. The length of this nucleus of old red sandstone from east to 

 west, between Little Elm and Masberry Castle, is about 8 miles, and its ave- 

 rage breadth from north to south about 1^ mile. The dip of its strata, which 

 cannot often be ascertained, is usually at an angle of 45", and is in every di- 

 rection from the axis of the ridge. 



The nucleus of sandstone is skirted by conformable strata of mountain lime- 

 stone, reposing on its flanks, but separated from immediate contact with it by 

 an intervening bed of lower limestone-shale. These exterior zones however are 

 partially concealed by the overlying deposits. Thus at Little Elm the oolite 

 reposes immediately on the lower limestone-shale. From this point to East 

 Cranmore the limestone becomes visible in a south-westerly direction through 

 a tract 3 miles long and 1^ mile broad, bounded on the south-east by the 

 course of the Cranmore brook. In the interval between the right bank of this 

 brook and the brook of Nunney, 2 miles distant to the eastward, the low table- 

 land of oohte, already spoken of, conceals the limestone. This same mass of 



* In the ditch of the castle, at almost the highest point of the mountain, is a well of water, which 

 is upheld by .some of the argillaceous beds of the old red sandstone. 



