466 ME. E. D. OLDHAM ON THE [Aug. 1 &94i 



on Woodbury Hill, I found some striated fragments, but neither so 

 abundant or distinct as at Abberley. On the Clent Hills there are 

 no quarries, arid the fragments lying on the surface are too weathered 

 to show the finer striae, if they ever possessed any, while it is im- 

 possible to say when or how the coarser ones were produced. 

 Abberley Quarry is consequently the only one where satisfactory 

 observations can be made, and the following remarks must be 

 understood to refer to it and to that portion where the quarry -face 

 exposes the unweathered rock in situ. Striated fragments can be 

 found in other places, but some of the points to which impor- 

 tance must be attached cannot be observed. 



Fragments showing a certain amount of striation are not un- 

 common, though by no means universal ; the striated fragments did 

 not seem to me more abundant than might be expected in glacial 

 debris, less so, in fact, than in some deposits whose glacial origin is 

 indubitable. The formation, however, consists of fragments of rock 

 of all sizes lying in contact with each other, and as the dip of the 

 beds and the slight deformation of some of the fragments show that 

 they have undergone some disturbance, it might be urged that these 

 striations were produced subsequent to accumulation. There are 

 consequently two separate questions to be considered, namely, 

 whether the striae were produced before or after the embedding of 

 the fragments on which they were seen ; and whether, if they were 

 formed previous to deposition, they were more probably formed by 

 glaciers or by some other agency. 



There are some markings to be found which must have been 

 formed by the pressure of adjacent pebbles, such as pittings, not 

 unlike those of the pebbles of the Bunter conglomerate and the 

 Nagclnuh. There are also scratches due to earth-movements sub- 

 sequent to deposition ; but, excluding these, one may also find a fair 

 number of fragments exhibiting a number of parallel scratches, not 

 infrequently crossed obliquely by others, and many of the individual 

 scratches can be distinctly traced for a couple of inches and more. 

 These seem too long to be accounted for by any movements that can 

 have taken place in the body of the rock, for it must be remembered 

 that to produce a number of close-set striae running across the face 

 of a pebble requires an amount of total movement exceeding many 

 times the length of the individual striae. I repeatedly searched to 

 see if there were any trace in the body of the rock of shearing- 

 surfaces corresponding to the striated surfaces on the individual 

 fragments, but failed to find them. Further, there did not seem to 

 be any regularity in the direction of the striae ; certainly, where a 

 broad surface of a flat fragment was striated it was generally found 

 more or less parallel with the bedding, but this is what would 

 naturally occur in a stream-deposit. On other fragments the striated 

 surfaces lay at every angle with the bedding, and the directions of 

 the striae in every azimuth. Moreover, it often happened that only 

 the projections, such as one of the worn-off angles, were striated, 

 while the rest of the stone was unmarked, a feature which is easily 

 explicable if the striation had been anterior to deposition, but would 

 hardly be expected if it had been produced subsequently. For these 



