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" massive" series. The first 400 feet contains fossils, the remainder 

 does not. The limestone is very variable in its character — iu some 

 places very compact, in others very oolitic. It is in this " massive" 

 series the well known great fault occurs. The contortions must 

 have been noticed by everybody who has passed aloTig the 

 road. The total displacement is estimated at 800 feet — i.e., beds 

 which were before separated by other beds to the thickness of 800 

 feet are now side by side. All trace of this at the surface of the 

 ground has been of course obliterated by subsequent denudation. 

 There is much difference of opinion among geologists as to the 

 extent of this fault ; some hold it runs to Radstock and to Blaize 

 Castle. In Nightingale Valley the coal with true coal plants is 

 seen in some places thrown up, and on the right hand side of the 

 river there is for a distance of about 200 yards " broken ground" 

 containing portions of several strata confusedly mixed together. 

 Continuing along the road it is noticed that the dip of the beds 

 from here is changed to S.E. The limestone beds which occur at the 

 upper part of the " massive" series here in consequence of the fault, 

 come in again ; the unfossiliferous portion is also repeated. Then 

 below this again comes in a series of fossiliferous Shales, about 500 

 feet thick. A cutting through these first by Cook's Folly has a 

 strangely Liassic appearance — the limestone here contains much 

 alumina. Further along the road, which (be it recollected) in 

 consequence of the dip, implies lower down in stratigraphical 

 sequence, comes in the Old Red Conglomerate and the Old Red Sand- 

 stone. There is a thin band which has been the subject of much 

 discussion as to whether it is the representative of the marine 

 portion of the so-called Devonian series. But only a few minutes' 

 halt was made here, for the words " lunch" and " appetite" were 

 heard as frequently as geological terms, and some of the party 

 were already pushing on more rapidly to Avonmouth. The New 

 Red lying unconformably on the Old Red, which is well seen in the 

 railway cutting, was the only other point of interest noticed. 



In walking on to Avonmouth many of the phenomena which had 

 been noticed were discussed, among others the appearance of a. large 

 hollow at the " Black Rock" quarry, where the roof had given in. 

 It was said there was a difficulty in accounting for this displace- 



