76 DESCRIPTION OF THE STRATA. 



what has been effected by the winds and rains at the one place, has 

 been accomplished by the waves at the other; for the strata running 

 into the sea, and forming Filey Bridge, present a surface so rugged 

 that it is difficult to walk on it; the soft and marly parts being washed 

 away, while the hardlfer parts, forming a kind of septa between them, 

 constitute a labyrinth of sharp knobs and ridges, in countless num- 

 bers and endless diversity. The hardness of this rock is increased by 

 its numerous petrifactions, the stone being usually indurated wher- 

 ever they are imbedded. This circumstance, however, is not peculiar 

 to the petrifactions of Filey Bridge; for the same effect is often pro- 

 duced by those of the chalk, the shale, and other rocks ; especially 

 when they contain a portion of iron, either in the form of oxide or 

 of pyrites. 



While we are speaking of the Filey Bridge rocks, it may be pro- 

 per to notice, that their dipping rapidly towards the south, while 

 they also descend into the sea towards the east, may be regarded as 

 corroborating the idea, that a great dislocation of the strata has oc- 

 curred at Filey bay, occasioning the disappearance of the oolite, and 

 perhaps of some other beds. The greatness of the dislocation may 

 be inferred, from the distance between the Filey rocks and the Speeton 

 shale, viewed in connection with the rapidity of the dip ; the interme- 

 diate space, now occupied with alluvium, being not only sufficient to 

 contain the thickest part of the oolite itself, but more than sufficient 

 to comprise the whole thickness of the oolite hills, at their greatest 

 elevation. 



Respecting the other beds in this series, it is unnecessary to say 

 much. They vary exceedingly in number and quality. To the south 

 and west of Malton, they appear to be extremely iew and thin, nay 

 in some places they may be said to be wanting altogether; the shale 

 that succeeds them being only a very little below the oolite. Thus 

 we find the shale close to the blue and grey limestone, at the quarry 



