Mr. R. C. Taylor on the Geology of East Norfolk. 285 



nearly upon the western boundary of the regular deposition of 

 crag : the few detached indications that are observed further 

 in the interior valleys, seem rather to denote its antediluvian 

 limits. Consistently with what is observed elsewhere, this de- 

 posit becomes thin and imperfect at its western edges, which 

 have evidently been operated upon by diluvial agency. The 

 high lands and the great accumulation of diluvium on each 

 side of the principal valley, render examination difficult : the 

 chalk itself rises above the level of the highest crag deposits ; 

 — the phaenomena attendant on the sinking of deep wells are 

 seldom observed or recorded ; and it is chiefly on descending 

 again into the other valleys of this district, that fresh proofs, 

 more or less positive and abundant, present themselves. 



Experienced well-sinkers, however, do affirm, that on forming 

 deep wells, in various places around Norwich, at a distance 

 from the river, they have occasionally encountered a stratum 

 of shells overlying the chalk. In one instance, at a farm upon 

 Mousehold, the depth perforated was 132 feet, of which the 

 first 88 consisted of diluvial gravel and sand ; then a bed, two 

 feet thick, of conglomerated crag shells, consisting of Mm^/ccs, 

 Cardice, Tellina:, and PaiellcE elongatce, immediately lying upon 

 the chalk. Here, therefore, was absolute proof of a conti- 

 nuous shelly bed, extending beneath nearly 90 feet of diluvium 

 to a considerable distance from its outcrop in the Norwich 

 valley. 



At Marsham, and in the adjacent vales, it is again disco- 

 verable, accompanied with many bones of animals, large ver- 

 tebrae, and horns of deer. 



Further north, at Aylsham, on sinking a well in 1824, at 

 the depth of 60 feet, a bed four teet thick of crag shells, was 

 met with. They consisted of the genera Murex, Turbo, Na- 

 iica, Mactra, Fe7ius, and Tellina. 



On reaching the coast at Cromer, they are again observed 

 at low water embedded in a sandy ferruginous stratum, resting 

 upon the chalk. Along the whole line of this coast, extending 

 from near Cley in Norfolk, to the Naze in Essex, in an extent 

 of one hundred miles, this formation has been minutely and 

 almost uninterruptedly traced, by myself. The result of this 

 investigation has been fully confirmed by able geologists, in 

 various portions of that district. (See Section II.) 



The remains of certain animals have been so often observed 

 accompanying the crag, that they may be considered as indi- 

 cative of its extent even when other proofs are not attainable. 

 Fragments of bones, teeth, skulls, and horns are repeatedly 

 met with by the fishermen, when dredging for oysters at sea. 



So 



