508 Notices of Memoirs. 



I 



II. — On Ceetain Phenomena in the Drift near Norwich/ 

 By John E. Taylok, Esq. 



T has been well observed that in Norfolk we possess the best 

 graduated series of later deposits from the Pliocene age upwards, 

 to be found in Great Britain. With the exception of the " Purple 

 Clay," found by Messrs. Wood and Eome in Lincolnshire, and 

 believed by them to be of later date than the upper Boulder-clay of 

 Norfolk, we have all the Pleistocene series complete. Notwith- 

 standing this, there are few " debateable lands " more open to dif- 

 ference of opinion than those of Norfolk. Every now and then, the 

 geologist who believes he has made out a complete case, and imagines 

 he can rest on his oars, is suddenly disturbed by some out-of-the- 

 way and apparently trivial discovery which upsets all his previous 

 calculations, and forces him to his Sisyphus task again. I believe, 

 however, that ultimately all these discrepancies will be found more 

 fully to bear out the glacial hypothesis. 



I have the honour to bring before the notice of this Section 

 several phenomena which apparently disturb the succession of the 

 drift-beds, but which in my opinion only confirm the theory of their 

 origin. About three years ago, my friend Mr. Harmer, of Norwich, 

 contributed a paper which was read before the Geological Society of 

 London, on a "third, or Valley Boulder-clay." This deposit was 

 found at Thorpe, near Norwich, and Mr. Harmer, who I believe has 

 since altered his hypothesis, gave to it its name of " Valley Boulder- 

 Clay," from finding it on the shoulder of the high grounds bounding 

 the valley of the Yare towards the east. Subsequently I conducted 

 Mr. Harmer to a similar deposit at Swainsthorpe, about five miles 

 from Norwich, where the Boulder-clay is seen resting on the re- 

 constructed Chalk, to the absence of the intervening series, which, 

 however, are found to the north and south of this patch, at the dis- 

 tance of less than a quarter of a mile. All these beds occur on a 

 plateau, away from any river valley. Again, at Harford Bridges, 

 two miles from Norwich, a similar bed of Boulder-clay is seen 

 lying at a lower level than the middle drift sands which occur about 

 a quarter of a mile off. Last year, in company with Professor 

 Liveing and the Eev. Osmond Fisher, I visited this bed, in order to 

 point out the seeming anomaly, when Mr. Fisher suggested what I 

 believe to be the true explanation in every case where the upper 

 Boulder-clay lies out of its true position — that it had been thrown 

 down in a deep furrow or groove formed by the stranding of an ice- 

 berg. Some of the localities where the phenomena I am about to 

 mention occur, may have been in a continuous line of such iceberg 

 action, and the intervening area may have been denuded into its 

 present form, so as to cut off the connection. 



In the cutting of a deep railway guUey, close by the well-known 



Crag-pit of Thorpe, near Norwich, there was laid open, about a 



couple of years ago, a section showing a north-easterly groove 



scooped out of the sand and pebble-beds, and having the Upper 



^ Eead before the British Association (Section C), Exeter, August, 1869. 



