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developed. Owing to the downthrow to the S. E., the bhie shales of 

 the Lower Lias (the Lima and Bmklandi beds) are brought down 

 and impinge with an upward curl against the clays of the Bhoetic 

 series on the S.E. Their line of junction is seen by the usual 

 appearance of water percolating down through the fault, and by the 

 difference in the shade of colour of the clays in dry weather, the 

 Mcetic clays exhibiting a lighter blue shade than those of the Lower 

 Lias. On the opposite bank to the S., and immediately opposite the 

 -foult, there are some features worthy of notice, and the following 

 section is exposed in ascending order : 5 or 6 feet of Lower Lias blue 

 clays, -with two bands of laminated limestone ; resting immediately 

 on the top band succeed 18 inches of gravel and sand, the gravel 

 composed principally of oolite, with here and there a piece of rolled 

 chalk, sub-angular flints, pebbles of limestone and red siliceous grit ; 

 to this succeed 5 feet 4 inches of fine silt and loam streaked yellow 

 and brown ; and above all 6 feet of remanie from Lower Lias beds. 

 Farther up the cutting to the N., on the same side where the beds 

 on a level with the rails are the rubbly beds of the White Lias, 

 the remanie is composed of White Lias, and the beds of silt and 

 gi-avel (the latter resting on a band of White Lias), are much 

 reduced in thickness. As to the origin of this fault ; probably the 

 same agency which was in operation to the S., at Twerton, enabling 

 the Coal measures to be worked through the Lower Lias, and 

 causing the great disturbance of the beds in the neighbourhood of 

 the Mendip Hills, did not affect these beds at Newbridge Hill, as 

 ' Mr. Moore arrives at the conclusion that those disturbances arose 

 before the deposition of the secondary rocks, and, consequently, 

 before the formation of these Bhoetic beds. We must, therefore, look 

 for the origin of this comparatively small disturbance in those 

 numerous sinkings and upheavals of the land which are constantly 

 going on in a more or less extensive scale, and are traceable 

 throughout our neighbouring hills. 



The peculiar interest attaching to this section consists in the great 

 development of the White Lias, intervening between the gray 

 Bhoetic clays at the base and the reddish-brown beds of the Lower 

 Lias above, the line of demarcation being distinctly seen, even from 

 the train, by any one passing through the cutting. Another 



D 



