282 Tmjlor — Drift of Lancashire and Norfolk. 



(with which he is so well acquainted) and those in the Eastern 

 Counties.^ I do not known whether Mr. Hull has ever visited 

 Norfolk, or whether he has been guided by Mr. Wood's description 

 alone. I have had the privilege of studying the deposits in both 

 districts, and can testify to the surprising parallelism which obtains 

 between them. The differences are even such as we should have ex- 

 pected, a priori, to result from local causes, and, instead of detracting 

 from the general resemblance, rather corroborate the opinion that the 

 deposits in both districts were formed under analogous circumstances. 



Mr. Searles Wood's outliae of Norfolk Drift is correct. We have 

 the three great divisions of Lower, Middle, and Upper Drift — the 

 last but one consisting of mingled sand and gravel. These are the 

 broad features which distinguish the Drift deposits of the North. 

 The principal distinction between the two is that those of the North 

 are considerably thicker than those in the East. True, the Lower 

 Boulder-clay along the coast attains a great thickness, but it is some- 

 what singular that it should so rarely be found inland, and then 

 only in bands of a few feet thick. Whether this has resulted from 

 the thinning out or denudation of this deposit in a south-westerly 

 direction or not, I cannot say. The coast Boulder-clay has been 

 formed principally by the wreck and denudation of the Lias,^ inso- 

 much that it obtains its blue colour from that circumstance, and liter- 

 ally teems with the re-deposited shells of the Lias, such as Gryplicea 

 and Ammonites. Its great thickness along the coast, and its thinning 

 inland, would argue that it formerly extended in the North-east, over 

 what is now the Grerman Ocean. The boulders are of Scandinavian 

 rocks in almost every instance. It is more argillaceous, and con- 

 sequently resembles its relative in Lancashire much more than the 

 Upper Boulder-clay does. In Lancashire it is largely developed, 

 and is extensively used for making bricks. Its almost entire absence 

 inland in Norfolk, therefore, prohibits any such application. 



As regards the Middle Drift in Norfolk, it resembles that in the 

 North more than either of the other two members. Like its northern 

 representative, it is found in alternate layers of gravel and fine or 

 coarse sand, is often false bedded, and the pebbles are much water- 

 worn. These are singularly enough composed of granite, quartz, and 

 trap, as the same bed in Lancashire, and I have even detected 

 portions of the silicious grit known there as the " Gannister rock." 

 The shells found in the Middle Drift of Norfolk complete the re- 

 semblance. At Stoke and Saxlingham (within ten miles of Norwich) 

 I have found Turritella communis — a shell which I myself found in a 

 similar position in the Middle Drift sands at Eeddish and Hyde, in 

 Lancashire ; as well as in the sands at Crewe, in Cheshire. Other 

 shells, many of them fragmentary, were also of similar species in 

 both localities. 



The Upper Drift or Boulder-clay of Norfolk differs from that of 

 Lancashire more than any of the other divisions. The boulders of 

 primary rocks are not near so abundant as they are in the North. In 

 fact they are generally Oolitic, or flint nodules little worn down. 

 I See Geol. Mag. Vol. IV., April, 1867, p. 183. » And Kimmeridge Clay .?— Edit. 



